Question: Does increasing the rear sprocket size to be the same size (or nearly the same size of the tire) cause the go kart to loose speed, especially as the tire gets bigger?
The question is a peculiar one especially for those that are making their own go kart and are wondering what ratio would work best on the go kart. 

The question is this again, broken down into pieces:

The rear sprocket is the same size as the tire.  If the tire gets bigger (and the rear sprocket correspondingly grows with the tire), what happens to the performance of the go kart?

Actually, nothing.  The speed does not change, and the acceleration does not change.

I thought the answer I gave was preposterous myself, until I did the math.  The following chart shows the corresponding Drive Wheel/Sprocket Sizes versus the overall top speed and acceleration (based on a 5 horsepower engine and a 300 pound gokart):

As the wheel diameter changes (the sprocket diameter changing proportionally with it) the top speed (MPH) and the acceleration (FT/S^2) does not change; they remain constant.

It is hard to grasp that as the sprocket and wheel grow together in size, that the overall performance would not suffer, but it does not.

So what does that mean for the go kart drive line enthusiast?  The rule of thumb stands, keep your rear sprocket as large as possible (as close the wheel diameter as possible) and you will have a decent go kart performer. 

As you notice, the ratios in the list all change starting from 6:1; 8:1, 9:1, 14:1 17:1.  So the ratio does not tell the whole story, but is a start.

So how does this knowledge practically apply to a go kart?

If you for example are building a wood go kart, and the rule of thumb is being applied to have the rear sprocket (or pulley) as large us the rear tire, then  what if you upgrade to a larger tire, from your small 7 inchers that you currently have?  The rule of thumb still applies; you will have to make a larger pulley (or sprocket) to make the gokart perform like it did before.
Just in case you are thinking that you do not need to increase the sprocket diameter, because you increased the tire diameter, then you are going to run into stalling smoking clutches, and burning belts.
For more information about drive lines and computer program to help trouble shoot your drive line problems, go to the http://gokartguru.com/go_kart_building_203.php.  In this course you will learn how to calculate and make your own drive line system that will allow your go kart to climb hills without smoking the clutch.
Don’t be caught making a go kart and then have the drive line be the major headache.  And you don’t have to spend a lot of money on drive systems, such as a fancy clutch, just to get what you want.
Again, the go kart drive line course has a computer program that helps maximize your drive line for optimum acceleration and hill climbing performance.  Stop scratching your head, and get the answers explained and at your finger tips.

Tags: Calculation Aids, Go kart Drive Systems, Latest Posts // Add Comment »

The wood go kart steering is based off a bogie mechanism where the front wheels are mounted to one axle and the main axle on the front pivots at a center point. The bogie concept is based on basically a wagon geometry however it is very efficient as far as vehicle dynamics are concerned, because it has a true arc path.

In order for the bogie system to maintain stability it must be constrained in the z-axis. What I mean by the z-axis is that the up and down motions of the axle system are not allowed to move. The side to side motions the x-y motions are allowed however the up and down motions are not allowed.

The reason for the constraint of the axle system is to keep it from suddenly jumping up in the air and causing an imbalance situation.

The main constraint with a bogie system is trying to get it to connect to the steering mechanism, such as a steering wheel. The basic way to make a bogie system move is through a cable system, where the steering wheel is turned and the cables are pulled in and retracted on one side and extended on the other side.

The rule of thumb is that when the steering system is set up, the ropes are wrapping when the steering wheel is turned to the left. The left bogie is pulling in in other words and so the steering drum is rotating counterclockwise and is pulling the rope in from the left side. The right side is correspondingly extending the same amount of rope that the left side is.

The relationship between the steering pulley diameter and the amount of steering wheel rotation is shown in the following graph. When you have a 2 inch diameter drum it takes approximately one full turn to get the full angling of the steering bogie system. This angling is approximately 26° to 30°. To get a 180° wrap or turn on the steering wheel the steering drum needs to be around 4 inches in diameter.
 
The downside to making the drum larger is that the forces double. So that at a 2 inch diameter drum the amount of force required to move one side of the steering wheel is 12 pounds. When the steering drum is increased to 4 inches the amount of force required to move the steering wheel is approximately 20 pounds or more.

If a larger steering drum is desired to restrict the steering wheel movement then friction reducing materials are required to make the bogie system not bind up.

In order to make the bogie system not bind the bogie can be lubricated with grease on the bottom rails of the frame. This will allow the bogies to slide back and forth with greased surface. If for whatever reason the grease is not working out as well as it could, the bottom frame rails can be coated with either a plastic material such as a polyethylene strip, or a stainless steel plate, or a copper sheet, or a galvanized piece of steel sheeting. It is important not to have any fasteners in the sliding surface areas otherwise the fasteners will catch and bind up the steering mechanism, more specifically the bogie mechanism will get bound up.

The bogie system itself needs to be coated with plastic or a steel material as well to reduce the friction between the two surfaces.  Grease should still be used regardless of whether or not you use steel or plastic so that the surfaces will slide easily.

Use of steel cables is appropriate, however, roller surfaces will be required to make the cables not bind up or cut through the wood frame work. Ropes can be used however a very strong expensive nylon style rope is recommended so that the rubbing action does not deteriorate the rope quickly.

It is recommended that the ropes be replaced every year.

Additionally the rope should be greased on every rubbing surface to make sure that the friction is reduced.

A rule of thumb about friction is that if any of these mechanisms are making noise such as squeaking noises then the surfaces should be greased so that the noises go away. Additionally the amount of force should be noticeably reduced when the surfaces are greased.

Tightening The Ropes

Tightening the ropes is accomplished by tensioning one side with a wrench. What essentially occurs is that the retention bolt becomes a mini tensioner device. The rope will be wrapped as the bolt is twisted. The compressive action of the bolt against the tube-washers will cause the rope to become blocked or bound in a tight position.

To tighten the ropes the steering mechanism is turned full to one side. Then the other side is tightened with the ratchet bolt mechanism until the slop in the mechanism is gone.

The actual diagrams for the rope layouts and the steering assembly are provided in the Wood Go Kart Building Series; and is explained in further details in the Wood Go Kart Video.

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One thing I like about projects is that they are mini building programs. Ever onward, ever upward, step by step, plug along until you finally see the fantastic results.

Go Karts as you know are those types of projects, but as you well know too, once the go kart is done, then what? Well of course another go kart, or tweaks on the existing go kart. But today I am going to seek to expand your horizons into other areas.

One thing that go karts do is teach you mostly physics, mechanics and some minor electrical. I remember growing up and my Dad was saying that electronics was the next wave. In fact I had my choice, I could have gone into Mechanical Engineering or Electrical Engineering, or even become a Doctor…but I chose what I was comfortable with: Mechanical Engineering.

I chose Mechanical Engineering because it was something I could touch and feel. To be quite honest I never was introduced well to the field of Electrical Engineering, other than by those who said “It is really hard, very math based.”

Needless to say, by the time I was half way through college I could see I could probably do Electrical Engineering, but I probably would not be as happy there, so I stuck with the mechanical world.
But this article is about opening up new horizons. DIY Home School Projects are an excellent format for exposure to many high tech fields. The downside to conventional education is the 8 hour day restriction. Additionally, the restriction on free thinking or stepping outside the box is generally discouraged. With many public schools shrinking their budgets in the tech areas and deferring their tech courses to colleges, the actual ability to get your hands dirty and do some tech stuff will not come until it is time to get a full time paying job.

And that is the Catch Twenty Two (or bite in the rear you did not expect) the business owners are looking for experience, especially in these tech jobs.

So let’s be real where to you get tech experience? Where do you get your hands dirty?

In Projects.

Projects are the backbone to any career choice. Or more specifically can show people what you can do with your own two hands, or your two brain halves.

The go kart project when done right gives you an edge in a world of mechanical design. Also fundamental to go karts is engine repair and upgrade. (We don’t go much into that on this site, but I am planning on releasing a book on engine diagnostics. Whether it will exhaustive remains to be seen. )

The project I am proposing involves multiple disciplines, mechanical, computer, and electrical. The nice thing about the times we live in is that pioneers, ones that I went to school with, developed software and wrote programs that are extremely useful to a mechanical engineer. Additionally, the electrical engineers for the most part service the mechanical world providing electrical plug-in solutions to a complicated mechanical problem.

For example an electrical engineer may provide a cam actuation package that involves servo motors and other electronic goodies versus a complicate cam profile that is fixed. You may not understand that last comment, “fixed cam profile.” But the best a mechanical world can muster is a one stab approximated solution, whereas the electrical world applied to the mechanical world opens the world of variables to the engineer.

With a push of the button a cam profile on a starving engine can be changed with a network of electrical sensors and computer mapping programs, or even better yet get real time data and give the best solution to the combustion problem at that moment.

What does that mean to the mechanical world? More Power! More speed for less weight. Moooore!

Okay just what is this project? The project involves like I said is multidiscipline but is yet in the young person’s grasp.

Okay what is it?

Well I can tell you what it isn’t…

It isn’t boring, it isn’t going to sit in the corner and never be used. It isn’t a go kart, but it could make go kart parts, perhaps….

Alright I almost let the cat out of the bag right there…

It is a Do It Yourself 3d-printer. There are about three different manufacturers of ready to build 3-d printers. They can be either ready built or they can be assembled by yourself.

A 3-D printer is a printer that instead of just printing a sheet of paper with a .0001 inch of material (such as ink on the paper) prints over and over again and starts building off of the paper and makes a stack of ink. Typically a 3d printer uses a nozzle or syringe to dispense material down and then build upon that material to make a 3d object such as a human skull or a carburetor intake for a go kart, or better yet supercharger component for the racing enthusiast.

Another way to look at 3-d printer is that they are the inverse of CNC machines. Instead of starting with a chunk of material and wittling it into a shape like a CNC machine, the 3d printer builds up material and makes the shape at the first.

These projects are not for the timid, or those that give up easily. These printers are projects that tax the mechanical genius to be efficient, the computer geek to use his skills and the electrical guru to come up with something better.

I have been watching this DIY 3d Printer field for a while now. What has spurned this urgency for this field is that though CNC machining is powerful, I believe 3d Printing has more power to it.

From a set up stand point there really is none, other than turning the printing on. With a CNC mill you have to be very careful and have everything homed in and placed carefully. Additionally the CNC mill is noisy and messy, the 3d printer is much, much quieter and there is less dust and waste.

So our project is going to be Project 3d Printer and we will see where it leads us.

You may be wondering why the change in focus? This is a go kart site. Unless you think I have lost focus fret not….remember what you can do to go karts? Supercharge them? Fuel inject them…the 3d printer can get us closer to that goal in less time that a CNC machine, because we can make mistakes without fretting. Do a redo overnight….

The next article will be comparing the different types of 3-d Printers and the directions that a DIY 3-D printer enthusiast can go with relatively low cost….

Tags: Latest Posts, Miscellaneous // 1 Comment »

I have been racking my brain on how to develop a rear coaster brake system for a pedal go kart for a while now and it dawned on me the other day that I was making it too complicated.

It does however require two bicycle rear ends to complete the task but in reality it is quite simple.

The way it works is that the coaster brake rear end from one bicycle is made to drive a solid drive axel.

Coaster Brake Assembly with spokes removed

The wheel  hub will need to be de-spoked.   A sprocket will then need to be welded onto the wheel hub.  This sprocket then will drive the rear axle.

The lower rear section of the bicycle should be retained and mounted into the framework  the go kart.   It is important to maintain a workable drive ratio, and typically 1 to 1 drive will work best for the weight involved on the cart.

Ideally the most robust drive uses the bike frame work (cut back of course) because it has metal frame work.  If you cannot afford to use the bike frame work, then metal plates are the next best option.  The metal plates are fixed into the frame work using sheet metal screws or lag screws.

Free Wheel System Put Into Pedal Go Kart System. The rear (grey system) sprocket is fixed to the main drive shaft.

When using a bike coaster system, a basic understanding is needed.  The way it works is that the hub drives the wheel and the inside of the hub acts as brake.  So in action (as many of us grew up with) the pedals cause the bike hub to turn in one direction, coast in the other and then brake when the pedals are reversed.

The important note in all this is that there is a brake arm that hangs off the opposite end of the drive hub.  This brake arm needs to be fixed to the frame work; otherwise the brake will not work.  What will occur if the brake arm is not fixed is that the brake arm will tend to rotate when the brake is applied.  So fixing it is important.

As you have been guessing, at least two bike systems are needed to make this drive system work.  The reason I say that, is because the drive ratio of 1 to 1 is needed, and in order to attain this a large sprocket in the rear is needed.  This large sprocket will be removed from a pedal system off of another similar bike.  Then this sprocket will be attached to the smaller drive sprocket on the coaster brake system.  Because of the forces associated with the pedal go kart (mainly how heavy it is)  a ratio of 1 to 1 or even higher is needed. 

Tags: Go Kart Building, Latest Posts // 2 Comments »

You may have run into this or you may run into this where you are riding your go kart on a bumpy, gravely driveway and suddenly the go kart stops running properly. It just up and quits.

“Why would the go kart suddenly quit?” Is the question in your mind and “What would cause the go kart engine to stop running, since obviously nothing touched it?”

 What you will run into is that when you are riding a go kart on a rough surface the engine will be bounced up and down and in this “ bouncing up and down” the carburetor is jostled up and down. The carburetor inside has a bowl, and inside the bowl is a float that floats literally on gasoline. When the go kart is bounced up and down the float can be bounced up or down and typically will jammed in the needle valve in its seat.  It literally jams the needle valve into its seat and the only way to get it released is to jostle it again.

 The jostling effect usually comes when you start up the engine in choke it because that’s all that will that will cause the engine to run. It will run almost indefinitely and that’s a symptom that you jammed needle valve. Typically we will frantically start adjusting needle jets trying to get things to work better, just so we can limp home. We will discover however that it is probably the float inside the carburetor causing all the grief.

 If this continues to be a problem you have an alternative plan, and that is to buy a new diaphragm carburetor, or find a new carburetor that has no float in it. You see the float is designed to regulate the gas requirements for the engine. A “floated” carburetor is designed to run on a level surface not a surface that is a hill or surface that is constantly being bumped. The diaphragm carburetor however is used on things that are bounced around a lot and change angle positions a lot. For instance they are found in weed wackers and chainsaws. The best way to find a diaphragm carburetor is to go to a local small engine repair store and purchase yourself a diaphragm carburetor that will meet the CFM requirements for your engine. Also you can shop on eBay and find some second-hand used diaphragm carburetors. You need to make sure that you get the right size carburetor otherwise you will be starving your engine for its gas requirement.

And finally the engines that are most susceptible to this particular ailment are engines I have bowl-float combinations. Some of the manufacturers have come up with rubber tipped needle valves which help solve this problem, however you will discover that even going up hills can be an issue so in case you’re wondering why your go kart is quitting after you’ve been running it over bumps and or going up hills, it is because of this float needle jamming issue.

Tags: Engine Diagnostics, Latest Posts // 8 Comments »

This is a typical proposed simple drive line for a vertical engine. This article will discuss why this system will not work. Put simply the ratio is way wrong and the belt will smoke.

Question: Can a simple pulley and twisted belt drive system work on a go kart for a drive system?

Answer: No, the belt will slip, and there will be tracking problems.
The answer seems simple enough, the belts slipping and belt tracking, but there is more than meets the eye here.

First off, if we run through the calculations, presented in our Go Kart Building 203 course you will discover that the following drive system will smoke the clutch.
Example: Typical Go Kart Drive Requirements
- 1.75 inch Drive Pulley
- 5 hp Engine
- 7.5 Inch Drive Pulley
- 12 Inch Wheel
- 325 lb go kart

This chart is from the Go Kart Building 203 Course. The chart is showing the profile of a 5 hp 300 lb go kart drive line system. To the far left the clutch will smoke and the go kart will go backwards. The engine may even stall or quit. The vertical line shown is where the clutch will start to grab and the go kart will go forwards, probably with a little help though. The farther to the right the better the accelleration and less clutch or belt problems.

The following chart shows that the go kart drive line characteristics. First it is showing that the ratio of 9:1 will make the belt smoke and the engine to stall. The go kart will not move very well without a push at any ratio below 9:1. Secondly, the ratio must be above at least 10 or even 11:1 to get a decent running go kart that is not constantly smoking belts.
What you will discover is that you will not be able to get a pulley large enough to satisfy the over all ratio. You will need to get a pulley that is larger than the rear wheel. In fact, just to get to the smoking point of the belt, you will need to have a pulley that is 15.75 inches in diameter.
So you will be forced to deal with drive reduction alternatives at the outset, just to get the go kart to drive.
So as you can see, I call it a “goofy twisted belt drive” because it is not realistic, it will smoke the belts, and not allow the go kart to go anywhere anyway. It may be simple, but is does not take into account the fact that the engine and belt combination will not work together.

In case you are thinking I am saying that twisted belt drives are not plausible, I am not, I am just saying that this particular drive line is not going to work.

In the Go Kart Building 202 course we go into details on how to use a vertical engine, while not using this “goofy twisted belt drive layout” but using a system that works very well, and is quite durable.
As a side note: there are two other major issues with the layout simple layout proposed, first when using a small pulley and a large pulley in a twisted belt drive layout is tracking. The belt has a hard time finding the small belt, especially when the engine drive is slacked, the belt tends to hop the smaller pulley. And vice versa, when the engine is romped on, the belt tend to jump the larger pulley on the slack side, as the belt is suddenly stretched and slacked. The slack section tends to hop out of the larger pulley.

And finally, the smaller pullies generate a lot of heat energy when high horsepower is used. The small pulley cannot dissipate the heat readily and tends to burn the belt, or even melt the belt. It is not uncommon on our wood go karts for example to burn through a belt in a summer. Belt drives work best if the belt is just transferring power smoothly and not being required to be a clutch, or have sudden on and off engagements.
An example of belts being used for extended periods of time are lawnmower deck belts. As long as the belt is just transferring load, and not being required to slip and then engage, the system will work pretty well.

Again, in our Go Kart Building 202 course we have a rock solid drive line that will not break down easily and requires minimum maintenance. That means, nothing is overheating or breaking down in the system.

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The Go Kart Drive Line Program

(This is an exerpt from the Go Kart Building 203 Book on the Drive Line Program)

After having gone through all these calculations you may be anxious to get some answers quicker.  The go kart program will help with that.  Though it is not as exhaustive as the graphs and formulas it will get you answers at the click of a mouse.

The go kart program is broken down into the following areas:

Inputs section for the program. The Frame Weight, Person Weight, Engine Hp, Max Engine RPM, Rated Rpm and Clutch Engagement RPM

- Go Kart Specifications
- Go Kart Engine
- Go Kart Clutch
- Go Kart Drive Line
- Go Kart Calculation
- Go Kart Results
- Go Kart Recommendation

 The go kart specifications section is gathering information about the weight of the go kart and the weight of the person. 

The go kart engine section is gather information about the engine horsepower,  the horsepower rating rpm, maximum rpm and the clutch engagement rpm.  The default setting for the hp is a 5hp@3600 rpms.  The torque engagement rpm is 2200 rpm, which has been validated by in house testing.

The Drive Line Section

Go Kart Drive Line System Info, starting with chain pitch, clutch sprocket diameter, Jack Shaft 1 Sprocket, Jackshaft 2 Sprocket, Final Drive Sprocket and Tire Diameter

The drive line section is designed to take into account a jack shaft system.  The program is by default set up so the Jack Shaft system is ignored, or it is neutral in the calculation by making the input and output sprockets the same size.

The drive section is composed first of the chain pitch (this affects the diameters of the sprockets), second the clutch drive sprocket, then the J1 (or Jackshaft 1 sprocket) , the J2 (or Jackshaft 2 sprocket  which is typically a very small sprocket) and finally the Tire Diameter.

Calculations Section: Starting with Total Weight, Ratio, Chain Tension of Jackshaft 1 and Jackshaft 2, Max MPH, Clutch Torque, Clutch Status, Hill Climbing Status, Accelleration Up Hill, Accelleration Flat and whether the tires spun or gripped.

The Calculations Section

The calculations section shows the essential data needed to determine if the drive system is going to work or not.

First the total weight is important for go kart performance; the program totals that up for you.  Second the OVERALL ratio is calculated, along with the chain tensions on both the jackshaft systems.  These are labeled Tension1 and Tension 2.  This data is needed to determine if the chain is going to snap or not  (unfortunately the program does not tell you if you chain is overstressed or not…yet)

Third the program also

calculates the maximum MPH of the gokart based on maximum engine rpms. Fourth it calculates the clutch status and clutch torque.  The Hill climbing status is important for go karters who are seeking to go off road. 
At the bottom of the page the program gives recommendations.  Because the hill angle was set at 10 degrees the program is recommending changes to get the go kart to climb the hill.  The overall ratio is key to this recommendation.

As you can see this program run was not successful for climbing hills.  The go kart in fact would go backwards down the hill, which is just the opposite of what we are trying to achieve. 

Upgrading The Drive System To Handle Hills: How It’s Done

In order to get the go kart to climb the hill, the overall ratio needs to be updated. 

To get  that to happen, the large sprocket on the jackshaft needs to be made larger.  So the value of 30 teeth was put into the program and as you can see the overall ratio was upgraded and the program settled down told you that you the go kart can climb hills now!

Jack Shaft Inputs. Jack Shaft 1 is the larger driven sprocket, Jackshaft 2 is the driven smaller sprocket

Recalculated to climb hills

 
Flat Landers Go Kart Calculations

Not all of us want to climb hills, so the program has the option of changing the hill angle value to 0 (zero) degrees.

(The program by default is set up for climbing hills at 10 degrees)

 When the angle is changed to Zero, the program will calculate the performance of the go kart assuming no hill. 

The recommendation section will give a drive system that is designed around the optimum accelleration of ¼ g or 8 ft/s2 .

Hill Angle Option can be changed to zero degrees for Flat Surface Calcs

Flat Surface Calculation

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Well it was a short year. Things happened way too fast, and projects went way to slow and uncompleted.

It is going on two years now and the dual seater go kart is not complete. Which is frustrating, but necessary seeing we are videoing the whole process. Our ambitious goal was to make a two seater go kart out of an old lawn mower, using all the components from the lawn mower.

Additionally, we are using the e-books that the Go Kart Guru has on the web site. We actually have gotten pretty far. We are putting the seat on the go kart, making it so the seat can be easily removed and placed. Now that the go kart is sitting in the garage, we removed the seats so that winter varmints are not infesting the seat, and cats ruining it.

Come this spring we should be getting the first test drive in.  That will be exciting.

As far as new products are concerned we are coming out with a printed version of all the books in one big monster volume.  It is about 400 pages of material.  That will be released at the end of the month.

Additionally, we are coming out with a new book that is full of charts that show how to set up a drive system for a go kart ranging from 5 to 18 hp and 200 to 500 lbs in weight. There are two ways to set up your go kart, one for driving on level surfaces, and two for climbing hills.

There was an overwhelming amount of people who were emailing and asking why their clutch was smoking and how to set their go kart up so it could climb hills and not smoke the clutch. I used these charts frequently in email responses to help out.  I figured it is high time I just put together a book that will address all the drive systems questions.

The 201 Drive systems book is more than sufficient to get the rive system set up properly but it lacks in some areas, especially when a clutch will smoke. So this new drives systems book shows when the clutch will smoke for a whole wide variety of weights and horsepower set ups.

Later this month we will be releasing this book. I am considering putting together movies that will accompany the book to help explain how to use the charts better.

Last year the goal was to put together a curriculum for shop classes. We are really close to having this shop class package put together. It is pretty involved, includes videos and tests. So we are about really close to getting that released as well.

Keep asking questions they help fuel more helpful ideas on our end.

I hate putting together a newsletter without any helpful advise so here are some tips:

8  Tips to Help In Your Go Kart Project

Tip #1  Frame Design: When making your frame use 1×1 tubing with at least 1/8th wall for maximum strength.
Tip #2  Brake System: A live axel system is actually simpler than a one wheel drive system. As a result disc brake system is the most readily available and cost effective. Remember to leave the disc so that it can float, other wize it will bind and wear out your brake system.
Tip #3  Throttle System: When setting up your throttle be sure to have a positive return in the pedal, but most especially at the carb linkage. This is more a safety issue, so that when the pedal is released (or the cable breaks from the pedal) the throttle is in idle or in the slowest speed.
Tip #4  Drive System Layout: The simplest and most cost effective drive system is the centrifugal clutch system. A rule of thumb is to have the rear sprocket be at least 85% of the diameter of the rear wheel.
Tip #5  Steering System: The common mistake in drive systems is to have the linkages around the foot pedals. In other words, when the gas pedal is full pushed down it hits the steering linkages cause a bind up on the steering. This is a dangerous condition. Additionally, the steering is usually not set up to account for the 50/50 weight distribution, so the go kart tends to go straight. Typically the steering and wheels are behind the foot pedals for proper weight distribution.
Tip #6  Tires: Low cost tires that are found at retails stores on push dollies or cheap wagons can be used, however, they do not have the proper rubber construction to withstand driving conditions and will wear out very quickly. Beware of cheap rims they can rip loose of the hubs and fail prematurely.
Tip #7   Safety: Always wear safety equipment such as gloves and a helmut. Smaller drivers should wear chest protection, such as a ribtech unit, so that when a collision occurs they do not hurt their chests or have internal organ damage. Flipping a go kart is the most traumatic and most preventable. Good driving habits and lower speeds are encouraged for younger drivers. Dis-allow go kart drivers who will not observe safety and be sure to educate all drivers about safety.
Tip #8  Where to Drive: Driving karts on the street is against the law. You will be arrested and get a ticket. Also, there are serious insurance issues if an accident does occur. Sadly the news has some occurance where somebody has entered the roadway and gotten killed while riding their go kart. Go Karts are only legal on your property. A large open area is recommended: trees, cars and pedestrians are major hazards to go kart driving.

Tags: Latest Posts // 1 Comment »

The weekends  they come and they go.  You ask a guy on Monday morning what he did this weekend and he will say it was way too short.  Usually that means is that they had limited family time to themselves.  They did not have any time to do any thing thing really meaningful.  They were  just going through the motions, not building any memories per se but more going through the motions of life.  It just went too fast.

It doesn’t have to be that way.   Life doesn’t have to be a hurried, harried mess where it is paycheck to paycheck all the time.   Many of us are pressed for the paycheck to paycheck and don’t even have any idea about how to have fun without spending lots of money. Sometimes we’ll run off to an amusement park over the weekend and lay down $200 to  $300 and then it will be over.  And after the weekend has been done we will ask ourselves “was it worth it?”

Why not do something that can build memories for many weekends to come, versus a weekend that was just spent, or zipped by?

What we are proposing is the go kart project.  The go kart project is something that can be done over series of at least seven weekends.  Which is basically a summer or it can be done in the Winter and in the go kart project what you do is gradually assemble  or manufacturing yourself a go kart out of basic materials.  

What we are offering the ability to make a  wood go kart out of basic wood materials that you will find at the hardware store, and basic wheels, and components, that  again you will find at a hardware store, or you can find online.

You can easily build Go Kart for under fifty dollars .  We built our go kart out of all sorts of junk in the garage for under $20. We actually brought that to you video and that actually took us a weekend to get gravity part working out and then another  weekend to get the engine part working.

What we have is a Wood Go Kart Building Bundle Video  which includes a video and a book.  In this bundle we include some important books that we produce on our Go Kart Guru website that deal with drivetrains and vertical engine drives.

One of the biggest headaches that people have is that they have an old lawnmower sitting around and have no idea how to make it work or use the components to make a go kart work. With the Wood Go Kart Building Bundle Video we supply the video that shows you step instructions on how to make the go kart itself  using horizontal engine.   It  is a basic belt drive go kart and does not use fancy components so it keeps the costs down.

You maybe wondering to yourself “Is this thing safe, or is it just a piece of junk we’ve thrown together?” 

Well that is a good question I’ve often seen go karts that people put together, on the internet for example, and they work, but they are not really something I would be proud of.  Something that I would say “My son and I we work on this go kart and we put it together.”  Its not really something that you would be proud of, something that will last years instead of weeks, and something that has brakes that are worth something versus a stick that you just rub on the ground and you just hope that it stops when he get down to the end of the driveway. 

On this go kart we have seven different safety features all which are designed around the wood go kart and its ease of building

The wood go kart project is something that you can use normal tools with, a regular saw for example.  We used a jigsaw.  You may have to invest in a  $39 jigsaw to cut out some circles. But other than that is uses basic wood screws, two by fours, plywood, and regular bolts, heavy nylon rope (or cabling depending on your choice).  You can have a working gravity go kart in at least one weekend.

Just imagine being able to have a go kart running, a go kart put together, a go kart that you and your son  (a son or daughter actually) worked together on over the weekend and imagine all the building memories that you could have.  One of my fondest memories was working with my dad really that is all that matters.   It didn’t matter if we were working bee-hives, lawnmower or even just clean the garage, I was with my dad and was fantastic. 

Many kids are like I was, my Dad was gone a lot.  Most kids they don’t have a dad figure other than a gym teacher, or school mentor.  They don’t really have a dad figure because the dads are not around very much.

The weekends unfortunately are about the only time that you can get together that you can get together with your son for an extended period of time.  What better way than to get a bonding experience going than to build something.

The wood go kart can be assembled in one weekend or a series of weekends depending on how fast you go, but I have got to tell you, when a kid gets involved, he get a little impatient and wants it up and running pretty soon. The nice thing about that wood go kart though is a kid can get out a hamer and saw, even a drywall screw gun.  And be able to zip things together for you real quick.

It’s a great time to show kids how to use tools,  learn about safety in using tools, and learn about safety in swinging hammers.  They can  gain that experience so that they can be become effective carpenters so that when time comes when they’re in high school or off  their own that they have a skill under their belt.  The wood go kart is a beginning of that that.  It is a place where a kid can start and learn a couple of things at the same time.

They can learn mechanics, they can learn electronics, they can learn woodworking, they can learn electrical wire routing, they can learn basic physics, and they can learn basic mathematics when they have have to add up all of the components for the wood go kart bill material. There’s a whole host of skills that can be introduced and learned by kids during this wood go kart building process.

What we are offerings today is the Wood Go Kart Building Bundle Video.  What this consists of is a full printed version of the Wood Go Kart Books I and II, plus two go kart drive books.  The standard drives book, which shows you how to put together a drive that will enable you go kart to climb hills, secondly the vertical engine drive book which shows you how to use a vertical engine without flipping the engine on its side, but using it the way it is.  Additionally there is a full video which shows you step by step how to put the go kart together from scratch.  And in this case it is a father and his sons putting a go kart together in the basement of their home during the winter months.

So take make some memories….start a go kart project today.

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The ambitious go karter had this grand vision of a go kart that would do all sorts of things. It would hold four kids, have a vertical engine, be made out of wood, used lawnmower wheels, and go 10 miles an hour. It started to turned into a mini behemoth as more and more boards were being tacked onto this go kart platform.

In the final hours of the go kart experience the go kart was test driven using a tractor. A lawnmower tractor that is, that pulled on the go kart down the driveway. All three kids piled into this go kart and proceeded down the driveway at a very slow rate as the tractor slowly pulled them along. Then things started to happen. Go kart wheels started to fall apart and break up. The rubber on the rims of the wheels literally peeled off and fell off. All four wheels were down to the metal rims and the rubber had fallen off of the rims on the go kart.

What happened here?

What happened here is that the go kart was over weight by at least 200 pounds, and the idea that being able to use a puny little lawnmower engine to get the go kart to even move was not plausible at all. The wheels themselves demonstrated that the go kart weighed too much.

What were sare seeing here is a typical non-planned go kart, one where the idea the picture of a go kart is in one’s mind but the actual practice or practical application of it is out of one’s grasp.

I ran into that a lot when I was a kid. And this is where somebody who can instruct or a good book like the books that we provide in the Go Kart Guru series can help a lot with that.

For example having a go kart be overweight can easily be remedied by doing a drive system diagnostic. Using the go kart guru program that is provided on the Go Kart Guru website you can tell whether or not the engines going to be able to pull the go kart or not. Secondly in the go kart building series, where we show you how to put together a frame, weight is a very large consideration for strength of the frame and size of a components such as wheels, drive gears bearings, steering systems and so forth.

This go kart that was in the story, was a wood go kart, however, it lacked good design considerations. The assumption was made that the go kart could be just built up from the platform was put together and no consequences would result. The result was obviously way too much weight. As a side note, using lawnmower wheels that come off of lawnmowers typically will not work on a go kart because they don’t have:

1.) Bearings that are designed to travel much faster than 1 mile an hour and
2.) The rims themselves are not designed to carry a lot of load.
3.) The wheels themselves and not designed to take a sideload such as cornering.  The wheel will break or twist.

A rim that is needed for a go kart needs to be something that comes off a riding tractor or a go kart wheel that is actually designed for go karting. 

And finally, beware of bearings that are pressed together, they don’t last very long because they are not designed to take sideload. See the article on pressed together bearings for a better grasp on this subject.

When you’re designing a go kart you need to keep in mind obviously the weight and the horsepower. One of the major misconceptions by go kart builders is that they think they can just slap on a really big motor and use actually a really large clutch, but they can use a smaller drive here and not suffer the consequences of smoking clutch.

A smoking clutch is a problem related to clutch engagement and the RPMs of the engine. On larger engines for example you may get a clutch that is rated at 24 horsepower, however it is designed to engage at 2000 RPMs and may slip at that RPM because engagements is supposed to occur.

In order to get the clutch to grab more the spring rate on the clutch needs to be lessened otherwise the clutch will just slip at that 2000 RPMs.  You need to exceed the 2000 RPMs probably up to like 4000 rpms  in order to get it to grab well and then continue on. Typically what you will have is a go kart that has a governor that will not allow the engine to go beyond 3600 RPMs and therefore may cause the clutch to smoke

As a rule of thumb the go kart should not weigh more than 150 to 200 pounds, and the engine size does not need to be much larger than eight horsepower. You will get decent performance out of the go kart at most inclines up to about 10° (which is  a typical hill) and you will get really good straight-line performance as well. The ratio of the engine to the rear wheels should be around 10 to 1.

And as a final note the rule of thumb for rear drive sprockets is that they be close to the diameter of the rear wheel.

For more information about go kart drives systems, go kart steering systems, go kart braking systems, go kart frame design and much more, visit the go kart guru bundle, where you will get 9 ebooks, plus go kart plans for free.

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