Fort Worth Motorcycle Riders

I was told to keep 42psi front/rear since I bought my bike, so I have been.
I put a new 2CT on the back ~ 500 miles ago, 42psi. Yesterday after getting about 10 miles on the day I came up on the cloverleaf at 360/303 and just as I was about to get there another sportbike came out of a corner and dove into the corner I was about to go in so I gassed it a bit more and started chasing this guy.
The back end kept bouncing around on me. I was at 50~55 hard over and I was trying to pull it over more and speed up but when I did that the back felt "hoppy" so I didn't.
I have done these corners about 10mph faster without draggin but that was different tires.
I have 42 in the front and 42 in the back. I'm thinking of dropping the pressure to, say 38 F/R ?
What do you know about tire pressures and the affect on cornering and such?

The manual on my GSXR said 46psi in the rear tire. I never run it more than 34-36 cold. Same for all my bikes. 50+ PSI is very dangerous Karl, even hot...

Mfg's reccomendations are a good compromise between grip and tire longevity. You're definitely not going to have the same grip at 46 as you are at 38, but running the higher pressure will extend the life of the tire (then again, since you're running 2CTs, I'm guessing you're not overly concerned with tire life . Honda recommends 36 F / 42 R for the VFR, and that's what I run for the majority of my street riding; I'll drop it down to 34/38 for an intermediate ride, and even below that for the track. It's basically up to you as to where you want to draw the line between grip and lifespan. Also, you might want to recheck those pressures against the owner's manual; in almost every example I've heard of, the recommended tire pressures are lower in the front then in the rear, and I don't see why the Sprint should be any different.

You may also want to check your suspension settings, changing the pressures in your tires can affect how the suspension feels. Or I should say what you feel the suspension is doing underneath you. BTW 42psi f/r sounds to high to me it should be like Skego says 36psi front and 42psi rear. Running that high of tire pressure would affect the front end more than the rear. It would make the front end chatter, bounce, basically feel squirly. If it was the rearend then I would say you might have other problems.

You should try it again with a lower pressure on the front (36psi). If it feels the same way take it one step at a time and check the rear wheel and tire. First check the tire for uneven wear, bumps or lumps, cuts or missing chunks. Second check to see if your alignment is true (your rear wheel could be off from when the tires were changed). Third check the balance of the rear wheel you could have lost a weight (usually this is the most common problem). If none of these check identify your problem check the rear wheel for straightness (it could be bent, highly unlikely but it can happen).

Take it easy on those cloverleaves the Arilgton PD is always patrolling them.

I know it's a different bike, but my Bird calls for 42, front and rear. I don't run it that high ... 36 on the front and 40 on the rear seems about right. That's on the street. On the track, that drops down to about 28 and 32.

I don't know if you have a tire inflation problem. At 42 psi your tires shouldn't be hopping around. In my opinion you have a rear shock issue. I have run those tires for two years now at many different pressures and never felt hopping, sliding sideways under acceleration but not hopping. Go get your suspension checked out, may need some tweaking. By the way, 42psi sounds right for factory suggested pressure in the rear but, it should be lower in the front, say 36.

The recomended tire pressure you read in your owners manual is for the max load. Depending on how much you weigh is what you want your pressure at. If you are over 200 lbs then recomended pressure is what you need for everyday riding but if you wanna corner a little better drop it a couple pounds. The lighter you are the less pressure you need cause under hard turns your tires won't flex as much.

The hard bouncing you felt is from your suspension, I found a site that lists every bike made after 98 on what the suspension should be set at for starters to get the best ride in turns, of course it is just a stating point but it is where a few people I know have it set at and corners are feeling better to me. I don't know the rules on posting links to other sites so if you want it just PM me.

Feel free to post up any links that help answer questions or will be of general interest. If you post something that isn't appropriate, we'll delete it and let you know in a PM.

I agree with firewa11. Low pressure is better, because as you ride the tires will heat up the air inside and cause it to expand. Thats bad if you have higher pressure to start with.

The number 1 problem they have found from Motorcycle accidents not involving another vehicle is under inflated tires. Something to think about next time you put in some air.

Is there any correlation between stunting accidents and under inflated tires accicents?

Yeah, stunters usually deflate their tires considerably to make wheelies and such more stable.