off road go kart

Im going to be building a off road go kart.and was wondering it i had to have caster ,camber if its only going to go like 20 25 mph

Depends - if it doesnt steer right, then might need to make it adjustable - most go karts only have tie rod adjustability , the racing ones have full adjustability, for different track conditions.

So caster and camber wont be that big of a deal on a off road go kart all its going to do is mudding.what about akreman or how ever you spell it

caster and camber are pretty critical if you want to turn well. Ackerman is pretty important also. 25 mph on a lawn mower is pretty fast.

Caster helps the wheel straighten themselves back out after a turn, and determines stability at speed. Without some caster built in the front tires would want to dart left and right, and you would be constantly fighting the steering.
This would be exagerated by larger oversized tires
Camber helps in the turns as the outside tire leans in as it goes around a curve, without it the tires tend to push in corners.

Ackermann in the steering assembly allows the inside tire to turn more sharply than the outside tire, It allows the tires to follow proper arcs through a curve, once again, drastically improving turns

Well i am stuck then i dont know how to do camber caster and ackerman

I have some pics of my freinds basic go kart - looks like it has a lil negative camber built into the spindles:



Heres a web page explaining caster, camber and toe in to help you out:

http://www.ozebiz.com.au/racetech/theory/align.html

I know racing tractors with direct steering have to position the top of the front axle 10 degrees rear ward - to help the steering wheel 'return to center' easier .

Tractor spindles are misleading because the bushings where the spindles mount are at an angle- then the spindle bends to hold the tire/rim nearly straight - that can be the manufacturers way to beat the ackerman effect.

This is what Ackerman has been described as ( on a racing tractor site) : Ackerman effect is caused by the relationship between the position of the kingpins and the position of the outer tie-rod ends (the inward angle of the steering arms) and by the use of two separate inner tie-rod end mounting positions. Ackerman effect causes the inside front wheel to turn substantially more than the outside front wheel. Mowers employ far more Ackerman effect than almost any other type of vehicle except karts and it is used for somewhat different purposes than on a car.
A car uses Ackerman to minimize the effects of tire scrub when the vehicle is turning a corner. A mower (mostly) uses Ackerman effect (in conjunction with caster angle and scrub radius), to make the inside front wheel move downwards as much as possible how!! (By making it turn more), in order to raise the inside rear wheel at turn-in. Some mowers have adjustable Ackerman, involving the use of different length tie-rods, and mounting them in different holes on the steering arms and/or steering column.

Hope it helps y out some.

If i buy spindles online is the camber and caster and ackrman already on those?

If youre just mudding it shouldnt be that much of an issue. Racing is a different story.

greener179 wrote:

If i buy spindles online is the camber and caster and ackrman already on those?

The caster and camber sre set in the front axle. ackermann is set by the angle between the axle and the tie rod arm/ (or whatever you want to call it.). A good manufacturer will be able to tell the angle on your spindle.

Do some research on rake and trail for motorcycles. it will help for the caster angles. No caster means a darting wheel that fights you all the time. Too much caster and it will be stone stable at speed, but hard to turn. it's all in the balance.

camber is essential for cornering. Stock tractor have some built in for a reason. Faster tractors need more. Race tractors have tons of it.

If you want to turn instead of push. camber is required. especially if you lock the arse end.
Consider camber as the effect that happens with a dirt bike ro bicycle front tire when you lean into a turn. The more you lean the faster you can get through the turn

Even if the main use is muddin. Sooner or later, everyone always takes a speed run. Adding wide tires to the front end increases the effects of poor geometry, and can cause severe instability. Also, larger tires mean more rotating mass, which means more mass that needs to be turned for steering.

So what degrees of camber and caster should i use it will have 20 inch tires up front

We run ours with negative 10 degrees caster, no camber. We run up to 40mph and ours steer straight, are stable, and turn well. Not saying this is what you should run, just saying what works for us.

As I'v mentioned in other threads, we are VERY rough on our tractors and tend to go outside of the realms of normal sanity, so take it with a block of salt