tire pressure

[yellow400ex05]

Does having a really high tire pressure hinder the acceleration of a quad? I just got my quad back from the shop and had new sprocket put on and i felt a big difference in acceleration and torque and it pick up easier. But and I was racing my cousin's z400 to see how much my acceleration increase and he was able to pull away still, not by much and he has stock gearing on his. BTW I have an 05' 400ex which means the gearing was a 14 38, i went down to a 13 up front and up to a 40 in back, i figured I'd pull away pretty well until we hit top end, but he got the jump on me and beat me by like 2-3 i lowered the front and rear tire pressure to 3.5 for more grip. I don't know but i expected a lot of acceleration but I'm kind of disappointed. before i changed my tire pressure i had around 8-9 psi i guess they filled them up because they thought it was low. :ermm:

BTW his has a k and N and a full bill ballance HMF series pipe, with an outerwears lid. I have the mods in my sig.

When I raced him in and un-planted bean field with the stock gearing and new Kenda's that i have which are 20 inch tires I got him really good, and i was able to hook up great because I'm only 95 pounds he's 130 The races that I did today were on pavement doing a rolling start in 2nd.


btw i haven't raced him yet with the lowered tire pressure.

[honda6490]

I usually run 6 up front and around 5 depending on the conditions in the rear. I keep the fronts the same. If you have good tires they should bite good in most conditions w/o having to drop psi. I rode today with 5 up front and it was sketchy turning hard felt like the tires were gonna roll off the rim, (havent got new razr 2's yet runing 3ply dunlops thats why but still).

Zach

[yellow400ex05]

Originally posted by honda6490
I usually run 6 up front and around 5 depending on the conditions in the rear. I keep the fronts the same. If you have good tires they should bite good in most conditions w/o having to drop psi. I rode today with 5 up front and it was sketchy turning hard felt like the tires were gonna roll off the rim, (havent got new razr 2's yet runing 3ply dunlops thats why but still).

Zach

yea with say and average 150 pound rider on my quad it'll pull up till 4tth with the old gearing and would hook up 100%, because I have new kendas but for me I just spin because theres not much weight at all going to the rear tires. I have beaten a 440ex and a couple stock raptors and a stock banshee but not by much the 440ex was the easiest to beat out of all of them by like 2-3 lengths, so the potential for my quad is all there but it just needs more weight on it to grab good and get the power to the ground..

some of the races were by luck and more experience, but I'm just trying to get my point across

[blasterandy]

Honda recomends 3.9psi in all tires. I like to have 4 up front and 4-4.5 in the rear. So 9 psi is high. You arn't suppose to put more than 36psi in the atv tires when beading em so that tells you how much 9psi is. When i got my first pair back from the auto shop they used 50psi :D Guess someone didn't read side of the tire.

[deathman53]

I use 5 psi in all my tires. I don't like alot of wheel spin. I would rather have it hook-up instead of wheel spin, my trikes is the only time I want to have some wheel spin, it aids in turning alot.

[wideopen4life]

i run about 4.5 in the front and 3 in the back i got razrs

[firefighterjosh]

I run no lower then 6 PSI. I ussualy run 8 - 10 PSI. Running a high pressure prevents tire roll, and improves cornering.

But in strait line drag racing a lower pressure would be better for better grip in most cases

[honda6490]

3.9 is pretty low, and you probably want the lower psi in the rear not the front.