I am thinking about boring out my raptor but cant decide what kit to buy I have a ct pipe and the have a 680 kit or i could do the craycraft thing and i think sparks racing has a 690 kit i dont want to go to big so that it isnt reliable. I do alot of trails and some mx stuff.

 

if you get a kit it will not decrease the reliability by a lot because it comes with multiple parts although just boring would decrease reliability i think you should get the craycraft 686 i have heard all good and no bad about those bad boys

 

I have heard absolutely nothing about ct's bore package, only thier pipes.

Sparks has about a year to 2 year wait. They do build a faster engine than craycraft does, but not by much.

Craycraft had a lot of issues with the JE piston and many owners have been busting rods. They do have good customer service and turn around time.

Trinity is hit and miss. Some people have some awesome bikes from them, some have lemons. They too use a JE piston, but have had no real problems with it.

Anytime you open the engine you lose reliability. Its just a fact that has to be dealt with and its the price you pay for being faster. That said, a mild build, medium compression engine can be great for trail riding and mx. 102mm is the largest you want to go if reliability is your main concern and trail riding is your main venue.