I was thinking about having a 13:1 piston installed in my yfz 450 to give it a little edge over the others I run with. Anyone think this would be a good mod. Do you think it would loose any reliability.

 

yah it would give you some edge get ready for race gas though

 

Could get cams while its still new so and you would save money over buying one later since you wouldnt have to buy all new stuff around it (rockers/shafts if the followers are on the rockers). They take alot less work to put in too.

 

Race fuel is no problem, I had to run it in my 250r for years. 210lbs of compression.

 

great idea ridley I never thought about that

 

What Ridley said plus a YZF exhaust cam and you're set. I assume that you are also planning to get a slip-on exhaust and different air filter?

 

Sparks exhaust on order. Still not sure about the piston. I might ride it with the stock piston this fall and during the winter put a bigbore piston in it from sparks. I am going to change the exhaust cam timing. I found out the wr and yz take the same cam they are just timed different.

 

The YFZ, YZ, WR 450's have the same cam (lift and duration), the only diff on the YFZ,WR is the decompression pin location.

 

I have read a tester for the yfz runs this piston without race gas and it hasn't detonated the engine or no kind of problems. Now I would probably still run race but the tester said he would probably use a 50-50% race and pump gas mix.