leaf spring design inspired by hot rods

[firemanjim]

You know, you COULD replace the leaf for a single coil-over shock,adjusting it so it has enough pre-load to keep the arms resting on the "stops" (arrestors) at "idle"......

 

[itsid]

yes of course, that'd be the "2k sportscar" approach, but for hot-rod'ish karts I'd stick to a leaf spring

'sid

 

[J_Walker]

Hmmm, I've always wondered what spring type would be good for gokart suspension. I have tons of fork springs [different motorcycles] that will never be used in motorcycle forks again [mostly because their stock and I've upgraded.] I've always pondered If I could re-use them in a gokart. Only issues I've ever come across is, over loading the springs, rebuilding some type of forks to house the springs, and of course spring height.

sid, oh master googler, do you have any information on springs?

 

[Scout]

I see what's going on now. The spindle will have to be fixed to the a arm which will cause the caster or camber to constantly change. If the rear end stays fixed i think it will be the only thing to keep the kart level in the turns. I don't know where you'll find a short spring. You'll need a special a arm to make it work I think, and no shackles since the spring won't be fixed in the center. I think it would be an interesting experiment to try it.

 

[Half-breeder]

I just started reading this(not FULLY read, just skimmed the idea and possible issues).

How bout adding a coilover to the 'formula'?

 

[danssoslow]

Yo dawg! We heard you like springs..

 

[Doc Sprocket]

I just started reading this(not FULLY read, just skimmed the idea and possible issues).

How bout adding a coilover to the 'formula'?

Adding a coilover would probably make the overall spring rate way stiff. A simple shock absorber, maybe. But ultimately, I see two larger issues. One, that as the suspension "compresses" (rearend squatting), I'm inclined to think the top of the arch will rise, thus extending the shock rather than compressing it. Two- the point here is IRS- and when only one side compresses, regardless of which way the arch of the leaf moves, the effect of the shock would be halved, according to the leverage principles.

Now- while this floating transverse leaf could work, as the leaf will act as an anti-sway bar, thus resisting movement with spring resistance, I'm not keen on the fact that it is allowed zero downtravel. IMHO, this isn't really suspension per se. It'd be half-suspended at best. Bumps and other surface imperfections are 3-dimensional. What goes up, must come down and vise-versa. While it's great that a "bump" would cause a momentary compression and rebound, a dip or hole won't.

Let's not lose sight of the purpose of suspension- a smooth, cushy ride may be the result, but it isn't the purpose. The purpose is to maintain tire contact with the surface regardless of surface imperfections, and this does indeed include dips and holes. If a rear tire (for example) cannot droop, one of two things will occur depending on weight distribution, speed, etc. Either the tire WILL drop into the dip causing the opposing front tire to rise in the air, or the tire will simply lose contact with the ground below it.

A reasonably quick correction lies in setting up the rearend so that static loaded ride height (including weight of driver, gas, etc) causes the rearend to sag just a bit, off the stops. Messing around with leverage points oughta do it.

It's all academic of course, and largely depends how important true suspension is to the builder.

 

[Scout]

Here is the main thing I see wrong with this design and the reasn I say you will need a special a arm, is that on hot rods yes they do have a single leaf spring in front like that, but they are solid mounted in the middle. If you choose to "float" the spring, you will need to move the spring attachment points to a "tower" right above the pivot of the a arm and effectively turn it into a bell crank. What you have now will just make the spring go up and down with no to little spring action. If you make the tower adjustable in some way you can adjust the spring rate.

 

[machinist@large]

A lot of this debate could be solved if every one read thru the wiki link that mckutzy posted on the previous page of this thread; it has a lot of in depth info including the how's and why's of the Corvette engineering team from when they first started developing their suspension.

A picture is worth a thousand words, and the wiki link has a nice handful. Just a thought.....

Pat

 

[shoppingcartking]

I have updated my design im going the transverse lear spring hot rod route, with a lot of custom flare. I will post new drawings tonight

 

[Scout]

A lot of this debate could be solved if every one read thru the wiki link that mckutzy posted on the previous page of this thread; it has a lot of in depth info including the how's and why's of the Corvette engineering team from when they first started developing their suspension.

A picture is worth a thousand words, and the wiki link has a nice handful. Just a thought.....

Pat

The difference is the Corvette spring is mounted solid to the chassis, and his appears to be only mounted to the a-arms.

 

[machinist@large]

The difference is the Corvette spring is mounted solid to the chassis, and his appears to be only mounted to the a-arms.

True, but some of the others have suggested center mounting it, and the wiki shows many of the pitfalls that could bite you if you aren't careful.

 

[mckutzy]

We'll there is the corvette route or one could copy an exsisting hot rod front end. I have seen some layouts so plainly simple you could scale the picture to your likeing, based on your wheel and what width you want.
No more wheel reinventing. Keep it simple.

I say this as I have thought out my new build(when the time comes) it will be a rear transverse leaf spring suspension bike. My idea will incorperate the basics from above cars.

 

[Orange Krate]

I wanna see someone do a gasser style, straight axle front end on a go-kart...completely pointless on a go-kart but I still wanna see it done

 

[shoppingcartking]

Here are the new plans, already got a lot of the peices to make it just need to make the actual axle and mounts, sourced a leaf from tractor supply and removed one leaf to loosen it up. Having the mount between frame and leaf custom made at a local machine shop.

 

[Scout]

I wanna see someone do a gasser style, straight axle front end on a go-kart...completely pointless on a go-kart but I still wanna see it done

I might take that one on... but not yet. I have a few other projects first.

 

[zachy90]

I would flip it upside down

 

[Bando]

I don't know if this pics will help, but here are.

 

[zachy90]

First pic looks good

 

[Scout]

What did that come off of?