My sons 03 predator has no power? I have fitted pipe, no rev limit cdi, changed rollers and clutch springs, and opened up main jet slightly and modified air box. yet my daughters stock 05 ds50 will still wax him off the line till her rev limiter kicks in. thank you for any help in this matter.

 

What's your compression?

 

haven't checked compression yet will try to get checked today. what would be good ,what would be bad? thanks

 

Above 70 and it should run OK.

I'm guessing you got a kit from someone?

 

checked compression 75-90 depending on how long I crank w/electric start. quad runs OK just not what I expected being it is a 2 stroke 90cc. I have a 49 cc pocket bike that will run faster with 200lb rider then 90cc predator w/70 lb rider. I custom made pipe from cr80 exhaust. I did the same to my sons old dinli 50 only used kx 60 pipe for that one. wish I kept the dinli it was much faster then this polaris 90. same clutch mods and rollers. but dinli would pull wheel stands w/200lb rider!!! polaris won't do it with 70lb rider??? top speed is also low for 90, so not the sprockets if that is what you think. I'm going to check compression's on my daughters ds 50 and see what thats like. I'll let you know.

 

Hard to say but the Pred should wheelie pretty easy too. You sure the jetting is correct?

 

not to sure on jetting. I still have stock carb and intake. I do want to change but I know it will be $300 down drain if it doesn't help. Checked my daughters ds50 it has 110lbs cylinder presure w/electric start. I think I will pull head and have it shaved slightly. and try to see about a bigger main jet for carb.

 

The jetting is REAL sensative. Fat or lean, it'll fall on it's face.

 

Try manipulating the intake to see if it helps performance (ie, cover part of it or remove the snorkle)

 

[img]i/expressions/face-icon-small-smile.gif[/img]Both of mine were running slow compression was down to 90psi. I rebuilt the top end, talk to Hetrick Racing and they recomended taking 50thousand off of the top of the cylinder not the head. When I was done comp was about 140psi and ran great!! But now are for sale, boys have move up to z-250,s.