Hey all.

I am working on an independant rear suspension setup for a minirail.. I was under the impression that I would need to use some sort of "slipshaft" in the rear drive axles to keep them from binding during suspension travel, but recently found some pics of similar buggies that used a solid shaft. Will this work well as long as I get my u-joints in perfect line with the a-arm mounts? I first thought that as the suspension traveled the driveshaft at each wheel would need to get longer or shorter, but I guess I am wrong.

Thanks

Heres a pic to show what Im talking about

 

Anybody have any help with this???

 

Even with "perfect" alignment, you will need some kind of slip joint in the driveline. Just component flex can wreak havoc on bearings if everything is set up rigid. Sometimes just having a keyed shaft that is not set screwed in place is enough to handle misalignment. It works for low speed/ low power setups. That picture you had looks like the upper u-joint can slide about an eigth of an inch on the inner axle.

For any kind of horsepower over about 25, I'd sugggest an actual splined slipshaft or some kind of CV joint setup that takes care of axle plunge, like old VW's or modern front wheel drive vehicles.

Hope that helps...

 

so you think the setup in the picture isnt completly "rigid"? I cant tell, but I didnt think just using the keyway instead of a slip- splined setup would work at all.
As far as the idea it might work for low power applications, that company that makes the design in the pic above uses bike and snowmobile engines in some. I added a pic of another setup, its CV, but uses a solid shaft as well. I'd really like to figure this out, I cant find a way to use a slip shaft setup cheaply and easily done. If I can just use 1" keyed driveshafts, simple u-joints/yokes and stub shafts made from quad axles (turned for bearings, use the exsisting splines and wheel hub) I could make them rather easily and without hunting used parts or spending alot.





another pic

 

IRS is not the way to go on a minirail. Our rail had irs and it caused many rolloevers. it now has a swing axle set-up which is far superior.

 

Well, The one I have now currently uses a swingarm. But I done alot of riding with it, and think with IRS I could really improve weight transfer/ balance and cut down my turning radius. I realize it will cause body roll and could make high speed manuvers more tipsy. I am looking to get my rear tires up under the engine as far as I can, and IRS is the only way to go to do that.

Heres a pic.

The thing is SOOO stable now its almost unreal. Losing some of that to gain a better weight balance is worth it to me.

 

bump, anybody else????

 

On a dual cv joint the inner tripod joint allows the axle to move in and out. There are rollers on a trunion mounted to the axleshaft that allow it to move in the outter cv housing.

 

yeh....why dont you use c.v's?????? we use them in REAL buggies and they seem to, and do work fine, and have done since the invention of the buggy by bruce meyers of the dune buggy. you could get them out of a small european car for cheap i.e a peuget or citroen(old ones, of course). just go to the wrecker's. if you experience ANY binding of the ball-bearings, cage, race(star) or anything take them out, throw them in the bin and go to the wrecker and get some more. but the second time, get some aftermarket cages. you will have to connect them to stub-axles of some sort for it to work, but it seems like the best option fo now. if the stubs dont fit, then they are SHl*T. throw them in the bin and go to the nearest machine-shop. get them to whip them up and voila!
all in all for the best-of-the-best it will cost a between $150-$500. ther you go.
also ask the guys at the edge products here in australia.
go to www.edge.com.au they should help.

 

You could use a corvette type rear suspension. it uses the drive shaft as the upper A-arm. Heres a pic of a quad wit IRS.


http://www.qrcv.com.au/irs.htm