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FWD Reverse trike. Anti roll?
TallGuySmallBike - 25/2/14 at 07:35 PM

Should i be putting and anti roll bar on??

Its a Front wheel drive Reverse trike.

Thanks


brum_gustavo - 25/2/14 at 10:53 PM

Since itīs a reverse trike, the rear suspension will have no effect on roll control, so it should be tuned just for tire grip and comfort. The front, on the other hand, will control chassis roll. Putting an anti-roll bar will increase load transfer, making the car understeer, specially because of the FWD, which is not very good. I would recommend stiff springs and no antiroll. But if you want softer springs fr comfort then an antiroll bar is a must. If the car understeers, you can increase rear tire load by increasing pressure (smaller contact patch) or using a narrower model or one with a harder compound for less grip.
During the construction of by Locost I started drafting a reverse trike, it makes it easier to use a FWD donor (RWD donors are getting scarce), and with one wheel in the back you can have a FWD car that oversteers, IMHO.
Cheers

GUstavo


v8kid - 26/2/14 at 11:28 AM

I take a different point of view

All the roll is resisted by the front. There is no roll resistance at the rear - period - so a roll bar will not affect understeer or oversteer whatsoever. The determining factor for understeer will be the front/rear contact patches i.e. the tire sizes you use assuming all other things equal - which they are not.


However an antiroll bar at the front will prevent the suspension from working. If the suspension is poo this will be a good thing maintaining original camber settings and reducing understeer however if the suspension is ace it will increase understeer as the suspension will be less compliant over bumps.

I suspect you may get another half dozen differing views.

Oops! I should have said roll bars do not affect total load transfer in the slightest only the front/rear distribution which does not allpy in this case

Cheers!

[Edited on 26-2-14 by v8kid]


brum_gustavo - 26/2/14 at 12:30 PM

True, the front controls roll. This means that in a turn the outer front tire gets the biggest load, which may be increased by a rollbar, or stiffer springs at the front. True, contact patches are determinant, but lateral load transfer still applies (the rear axle may be considered fixed and with zero track width), and and antiroll would still have an effect on front-rear balance, though not as in a four-wheeled car.
Cheers!


smart51 - 26/2/14 at 07:58 PM

All the roll control is done by the front wheels. You either have to have very stiff front suspension or a front ARB. Mine had the ARB from a cinquecento. I replaced it with a home made one that was nearly 3 times stiffer. Driving it, I could have gone further. I'd suggest you look into fitting one.