What's the difference in the 100, 100.5, and the 101 bore? I noticed you chose the 100 bore, why?

 

100mm bore is the stock raptor bore. Unless you have some cylinder wall wear issues you can simply hone the cylinder and install a stock bore piston.

If you had engine problems or if the machine has a very large amount of time on it you may need more than a cylinder hone to have clean cylinder walls. It's at this point that you would bore the cylinder to a larger diameter. You can also bore larger to gain displacement and horsepower. The different sizes of piston are for different bore sizes.

 

Thanks for the help...So when I get all this done, I will have to buy the Wiseco 11:1 piston kit w/ gaskets , the Kibblewhite valve springs , Hotcam stage 2 cam (all from Magic Racing), pay somebody to hone the cylinder and to put it all in. Is that all?

 

That's pretty much it. Of course rejetting is mandatory and you may want to play with your gearing afterword to get the most out of your upgrade. Take care when installing the decompression pin, it's very important to get it in correctly, other than that the project is pretty straight forward.

I didnt have to check my clearances when I installed the stage 1. I have heard you have to shorten the valve guide on the middle intake valve for the stage 2, but I didnt have to and I havent heard from anyone who has actually installed an 11:1 or lower comp piston with the stage 2 and springs that had to either. My clearances were fine for the stage 2, you may want to check yours just to be on the safe side.

 

I would tear down your bike and measure the cylinder before buying the piston Checked it for size taper and out of round. If you just put a piston in and don't measure it will just wear you ring out in a hurry.