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forum
12-15-2002, 05:26 PM
Ok people Know that We've basically all learned alot about front end travel lets learn about bumb steer! FIrst of all the following is what I've gathered from studying front end design's and what i've come up with in my own head! SOme of it may be wrong but im willing to bet most of it is very right!

In the past Many people beleived it had to do with the width of the frame betewn the a arms. This is half right and I'll explain. Bumb steer has everything to do with the pivot point of the tie rods in cunjunction with the pivot points of the a arms! Usualy the pivot point of the tie rods is narrower because of the mounts connecting the steering stem to the tie rods is fairly narrow in itself. meaning the tie rod ends pivot is not ligned up with the a arms pivot, Therefor as the a arms travel upward the leverage on the tie rod is going to change because the linkage is not the same legth. THen the tie rods pull and cause the bumb steer as the a arm travels up!. Back to the leagers narrow frame! since the frame is narrower that moves the pivot point of the a arms closser to the pivot point of the tie rod ends wich makes the leverage more equaly distributed through the tie rods and the a arms. making them move upward at more equal amount.

Remember im no teacher so if it was hard to follow read it again. If someone with a engineering degree (aka john arens) could tell me if im totaly out to lunch then that would be great. I gathered this all my self with no help whatsoever. I just thunk it up.

forum
12-15-2002, 05:34 PM
oo yes there are other factors that cause bumb steer. but thats a different type of bumb steer. like offset rims. 4-1 rims creat less leaverage for ruts to pull the handlebars outa your hand ect.

Fleshwound
12-15-2002, 07:42 PM
its bump not bumb carl...

forum
12-15-2002, 09:18 PM
shut the h3ll up! lol

forum
12-15-2002, 09:20 PM
ok i spelt it wrong!. I posted this when i was in a rush. and Im a terrible speller.

phatswinn
12-16-2002, 04:47 PM
seems like a logical reason for bump steer

Mxbubs
12-16-2002, 06:48 PM
You know, I forget, which is which, caster-camber?

Anyway, I have read in ATV sport that the angle (tilt) of the tire changes when suspension compresses, but a good a-arm set up lets it stay the same.

I was riding down a black top road the other day running about 40mph and I was watching my front tires. I got my springs backed off alot, so my quad is riding really low, I gased it, and the front end came up a few inches, the tires stay on the ground, and the tires tilt/alignment never change. They just stayed straight, with the same tilt. I guess that is good.

They are the Herrmann Racing +3's.

forum
12-16-2002, 09:25 PM
yea i see your point but that cause your going straight. when in the midst of a turn then hit some bumbs it tends to pull the way you are already turning. Bump steer isn't all that bad. i just like to no if what i thought for so long was right or not

400exBro
12-17-2002, 03:34 PM
good post there forum...

but won't a steering stabiler fix that problem???
I don't know becuase i don't have one so i can't tell...


Bro

forum
12-17-2002, 04:02 PM
stabilzers help, but they mostly help the typr of bump steer like when you hit a rut. and the tire want to pull the way of the rut. wich in actuality is the worst type of bump steer