What is involved in changing the stock cams to WEBCAMS? Is it worth it? Will it drastically improve performance? If so, where in the powerband?

 

Cam650,
You have found out about some new cams they are actually PBR's cam design should take around 5 hours of tinkering. They will give you 3-4 bike lengths advantage right off the start all the way up through the power band. The cams are definately worth it not to mention a better price than PBR's. These cams are designed for an auto clutch system not to mention they can also be used in a 700.

 

Do you have to rejet or add a pipe? Can you just install the new cams a you're done?

 

Here's another cam related question: Mickey Dunlap (Four Stroke Tech) recommends going up to 11 to 1 pistons with a cam change. His explaination is that with more valve timing duration you lose a little compression and the higher comp. pistons make up for the loss. Is the effect that great or is he just trying to sell piston kits. It makes sense, but quite a few higher output cams have been put in engines alone with good results. What does everyone think?

 

I think your right.

 

Forgive my ignorance on this subject, but again, must you make jetting changes or add a pipe?

 

Sorry. I'd want a new pipe or modded stock pipe to go with the cams; You're flowing more fuel/air through the engine with the new cams and the exhaust gasses need a place to get out in a hurry. You'll have to re-jet.

 

I went to their website www.webcamshafts.com and didn't see anything listed for the 650? Is their website just not updated yet? If someone has talked to them, how much are these camshafts? Are new valve springs necessary? If they are the same grind as the PBR cams but cheaper, I would be willing to give them a shot!

 

A couple of things to ponder. When you modd the muffler and intake you should increase jetting this is a given. When you add a cam it is not necessary to add more jetting but it wouldn't hurt either. When you increase valve opening the timeing is still the same it means the valves raise and lower faster but stay open longer. If you have a constant of time that the valve is to close and open for eg. the new cam will hold the valve open longer with an abrupt opening and abrupt closeing period. The timeing of the valve remains the same it's just the valve that is open longer in that period of time. A graph would explain it better. It is true a higher compression piston would help offset a more aggressive cam but remember this the timeing is still the same wether you have a aggressive cam and or piston. All a piston does is allow for more or less fuel to enter the space hence compression ratio.

Intake, exhaust, jetting are substantial modds what is left to enhance. Heads, piston cylinder/bore, crankshaft this is the next step and one can be done without sacrificeing perfromance from the other. As we increase our modds there will be definate benefit.

If you intend to race your 650 or just anihilate your buddy a cam is the next step.

 

BrianT,
They addvertize for 230 for the pair with a core charge of 230 so 460 together or 230 alone a good price as PBR wants 330 plus core charge.