david01 said:
hey guys i got a question, my son has an 06 yz85 other then the normal up grades exhaust,rad valve,and a rear sprocket with two more teeth. we both want more out of the engine it has plenty of power but can use more what is the best route to take. iam in IRAQ now so i want to give him all the support i can since i cant be there with him. we have a spare engine that i got on **** and is in good working order so we want to use it for this project.
TH Racing builds a great stuffer motor. This will give you the added boost without having to go the big bore route.
From their website:
KTM 85, YZ 85 and RM 85 Options
Package 2 (SX85, RM85, KX85) - T H Racing 85cc modified motor - $950 If you would like a cooler running motor than a big bore and AMA legal mod class motor. The Stuffed Motor may be your best option. our engine gets completely rebuilt and cases get machined, stuffed and reshaped to reduce crankcase volume and improved flow. Your cylinder is ported, exhaust ports are polished, and matched to the newly shaped cases. This along with a several other TH Racing trade secret internal modifications produce the modified motor of choice for many national level 85cc racers
YZ 103.5cc big bore Super Mini - Add $300 to package 2 or 3 price.