Well with my b-day is coming up so i'm gonna have some extra cash to buy some go fast parts[img]i/expressions/face-icon-small-happy.gif[/img] But my question to you guys is what should i do first cams or piston? What's the highest compression would u get for a trail/drag bike? Because i saw past post that said 14.1 is real hard on the motor for trail riding. What cams would u guys get if u wanted to flat drag but be able to cruise all day, hpr2 or 3? Thanks ahead of time for the advice.

Phil

 

Go for the hp3[img]i/expressions/face-icon-small-smile.gif[/img]

 

anyone else?

 

woods a1a2. and you can get a piston to for the $[img]i/expressions/face-icon-small-smile.gif[/img]

 

I would run 12-1. I liked the hpr4's that I ran. I have never ran the a1/a2 cams, but have the 109's and there good cams, just not in the same league as the hpr's. It's like having 8-1 compression to 14-1 compression, the 8-1 will get the job done but the 14-1's going to get it done faster. Do you want to run good, or fast?

 

Well if you can only do one or the other I would probably elect to go with the piston. I know several people who are only running a higher compression piston and stock cams. Personally I waited to do both at the same time. I went with a 12:1 and used a gasket that brings the compression back down to 11:1 so I can use 91 octane pump gas. Later I can always swap out the gasket with little effort to bring the compression up to the full 12:1. The problem with doing the piston is it is something you really only want to do once! I hate them damn clips Grrrrrrrrrr! ( insert gnashing of teeth)....Cams are simple so long as you don't lose the chain or gears down the crank...( I didn't do it, I'm just sayin) Anyway if you can wait I'd suggest waiting to do it all at once.....

 

Yea! what he said.....

 

alright thanks a lot guys, i guess i'll just wait till i get enough money saved up and get both, i'm gonna get the hp3's but not really sure what compression piston yet. I'll talk it over with mrhp and see what he says. so thanks for the opinions.

Phil

 

There is a balance between piston compression and cam profile. Intake valve size also plays a big role, but you can compensate for valve size up to a certain extent by changing the cam profile. You will never get the most out of a high compression piston, without a cam to complement it. Neither can you run a race cam on stock compression and expect it to produce good results. Yes, you might pick up a few ponies by installing the parts separately, but the right combination of these components will give you a real good bang for your bucks.