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i have three option on doing this to a single arm mini. could use some suggestions
option1- move the arm mount out to the lower frame rail. this gives me 2.75" on each side. a reputible builder told me this will cause it to dart. why??
option2- 2" wheel spacers. will this cause alot of bump steer???
option3- convert to dual a-arm using stock take offs from a drr or apex...
thx for the help
Moving the frame mounts or modifying the frame for the dual arms, makes the quad illegal for the production classes.
As far as it darting well I would have to look into that to give a good answer.
In theory as long as the toe,camber,caster,S.A.I are the same as stock,and the quad is "square"I cant see that being an issue. You may have to mod the steering post for bump steer though
Why not just buy or make wider arms?
Im not a mini guy,but I can tell you that by moving the a arm mounts by lowering and going outward you will increase bump steer in two different ways . the increase from lowering can be corrected by lowering the tierod balljoint mounts at the steering stem. the gain in bumpsteer from moving outward most likly can not be corrected,because if you move those same mounts outward on the stem it will cause a over center condition that will cause the wheels to lock when turning. im only guessing, but darting would because the wheels would be bumping out instead of in like most quads do. when the wheels bumpsteer out instead of in it will cause a darting condition,when hitting a bump or jump. as allready stated longer a arms is the way to go.one other thing that happens when moving the mounts outward is that you change the roll center .
thx for the replies guys. im going to keep the front at stock angles or as close as i can if i go that route. it wont be a hacked up job, ican tell you that. i did check out a ds90x yesterday, and i could probably make that plate on the front for a dual a-arm type setup. money would have to allow that though. will the 2" spacers on the front give too much bump steer???? keep the suggestions coming and thx
Don't run spacers on the front for any type of racing, I don't even suggest them for any reason. The tire will have to move forward and backward when turning, instead of pivoting on the inside wall of the tire. It increases the pressure needed to turn the quad, making the small racer get out of the proper inside position they should be in, in order to get the force needed to turn the handlebars. Moving the tire out will cause all types of scrubbing and pushing effects on the tire, as well as seriously increasing king pin/spindle pressure. I have seen alot of these import quads snap them at the apex of a corner... usually the outside tire!
the spacer wont add bump steer,but it does make it ill handling. stock the tires turn or pivot at the center of the tire ,when you put spacers on the tires turn in a arch around the center. this gives the wheels a mechanical advantage over the rider.
Which in turn adds more bump steer because you have increased the leverage. Thats just like saying a 3/2 offset has less bump steer than a 4/1.Quote:
Originally posted by fearlessfred
the spacer wont add bump steer,but it does make it ill handling. stock the tires turn or pivot at the center of the tire ,when you put spacers on the tires turn in a arch around the center. this gives the wheels a mechanical advantage over the rider.
no that is not bump steer.bumpsteer is the wheels changing direction as the suspension goes thru the travel.if you were to pull your shocks off and lock your bars down and then cycle thru the travel the wheels change direction.if both sides are moved in the same increments,at the same time,the wheels will toe in or out.now do the same with wheel spacers or offset rims and the wheels will toe in or out exactly the same as before. and i am saying there is no more or less bump steer with 3/2 or 4/1. from the factory the tires dont pivot exactly in there centers,the are slightly offset to the outside off the center.this is called scub and it gives you a feel of the road. when a person puts shorter wheels and tires, that will change the amount of scrub and 4/1 rims will correct it. if you were to draw a center line thru the upper and lower ball joints the center of your tire will be a little outside of that.now if you put shorter tires on the ball joint centerline will be further away from the center of the tire. most of this info is in a sticky in the suspension section.Quote:
Originally posted by chunky0071
Which in turn adds more bump steer because you have increased the leverage. Thats just like saying a 3/2 offset has less bump steer than a 4/1.
I cant do the math like all you guys that are good with that stuff but I can tell you that our Kasea was properly set up with a dual a arm conversion kit, had 1-1/2" wheel spacers on it, had zero bump steer and handled like it was on rails..very flat and extremely responsive in TT for the past three years. IMO the best handling quad on the EDT series. Just properly set up..