tire pressures at the track

[twinvipers]

tire pressures at the track and a sprocket question

What tire pressures should I be at when drag racing. Shinko on rear.


Also a sprocket question. I have a stock wheel base Gen 1. 1 tooth down in the front. Having a real tough time with it pulling the front wheel. It is lowered and strapped. It runs about 145mph. Would going back to a stock front sprocket help out /

Thanks

 

[03LEBUSA]

At stock wheelbase stock gearing would help out and is it a usoft or reg shinko. Again at swb even a reg shinko should not spin much so I would run as much as I could in the rear, I have heard of supersport class bikes running 60psi in the rear @swb if it does spin a little it will help with the wheelie problem. IMO swb riders need good clutch hand to control the wheelies. that and weight on the front and suspension tuning is about all you can do, but I would try the stock sprockets---Or put it out to even 60-61" so its still easy on corners but that would make 60' alot easier. takes time adjusting suspension, mine is 63" and goes 1.4 60' and no wheelie fighting at all and I pin the throttle at the line and clutch is all out by the tree

oh yeah make sure you are really squeezing that front down with the strap holding the front brake while doing it , I seen some guys strapping the front but there is some slop in there, sure you are doing that just thought I would say so though

 

[twinvipers]

I will put the stock sprocket back on the front. Air up the tire a bit. How do I adjust the rear suspension ?

 

[Mr Bogus]

60psi in the rear?

 

[Draco1340]

A good starting point is 20 PSI. If you don't spin you could raise up to as much as 28 psi, but going from 20 to 28 psi only gains you less than 1/2 mph. If you do spin, you can slowly drop the pressure all the way to 12 psi with that tire, but you will start to loose about 1.5 mph going from 20 to 12 psi.

 

[B@DA$$08BUS@]

Great info guys.
Posted via Mobile Device

 

[03LEBUSA]

60psi in the rear?

yes sir , seen some ama supersport bikes do it, on the street is one thing to spin at swb but on a well prepped track with a decent tire I never had a tire spin issue swb. you ever see the trap speed of those "stock motor" supersport bikes, they try every last option for speed.

 

[Mr Brown]

At stock wheelbase stock gearing would help out and is it a usoft or reg shinko. Again at swb even a reg shinko should not spin much so I would run as much as I could in the rear, I have heard of supersport class bikes running 60psi in the rear @swb if it does spin a little it will help with the wheelie problem. IMO swb riders need good clutch hand to control the wheelies. that and weight on the front and suspension tuning is about all you can do, but I would try the stock sprockets---Or put it out to even 60-61" so its still easy on corners but that would make 60' alot easier. takes time adjusting suspension, mine is 63" and goes 1.4 60' and no wheelie fighting at all and I pin the throttle at the line and clutch is all out by the tree

oh yeah make sure you are really squeezing that front down with the strap holding the front brake while doing it , I seen some guys strapping the front but there is some slop in there, sure you are doing that just thought I would say so though

Wow

 

[03LEBUSA]

Just to correct what I typed on tire pressure I meant 50 psi in the rear has been run in supersport on some of the 8 sec swb bikes sorry dont know where 60 came from

 

[sean06]

The tire pressure question really depends on your track prep and weather conditions. You could go one day and hook at 45psi and then go back another day and spin at 25psi if there is no or poor track prep and if there are no fast cars putting down some good rubber and some heat into the track. But at swb I never ran anything lower than 45psi on the stock rear tire and it never spun, and this was with 1.50 60's. Just wheelies and more wheelies.

And give the stock front sprocket a try. It will help keep the front down two ways. A taller gear will give less torque off the line and you will gain some wheel base with the smaller front sprocket

 

[Mr Brown]

I will put the stock sprocket back on the front. Air up the tire a bit. How do I adjust the rear suspension ?

Put all the pressure you can in the front tire. Take out all the damping and rebound in the rear shock so it squats quickly, and comes back up slowly. There are adjusters on the top and bottom of the shock, on the left side of the bike. (As you sit on it)

 

[sean06]

Put all the pressure you can in the front tire. Take out all the damping and rebound in the rear shock so it squats quickly, and comes back up slowly. There are adjusters on the top and bottom of the shock, on the left side of the bike. (As you sit on it)

You meant take out the compression and add rebound right? With the compresson and rebound set full soft it will be like a pogo stick going down the track. You want the rebound set stiff so it rises slowly

 

[Mr Brown]

You meant take out the compression and add rebound right? With the compresson and rebound set full soft it will be like a pogo stick going down the track. You want the rebound set stiff so it rises slowly

Tell you like I tell my kids, "You heard what I meant, dammit" LOL
Good catch, thank you.

 

[sean06]

Lol, I figured thats what you meant