i noticed you were asking about the airsal cylinder...Save your money and get something worth it,You would be better off having your cylinder ported,ive got a +3mm cylinder thats already done up that will run circles around that firebreather,all you would need is a +3mm crank and the cylinder and your set.If your intrested ill cut you a killer deal.The cylinder came off a running bike,this setup was beating banshees on asphalt drags in the 1/8 mile and i have video to prove it