426

[mack400ex]

lets say i got a 426 piston...what compression ratio should i get, i want reliabilty!? i get 103 octane for free so gas is not a problem.will i be happy with it for x country? and what other parts should i get to help the engine due to the upgraded piston?? gaskets etc.?

[cals400ex]

you can run pretty high compression with 103 octane. however, the less compression, the more reliable more than likely. the cosmetic flexsteel gaskets are good gaskets. a cam will really really wake that bike up with high compression. you may have issues with the head studs pulling out with high compression. also, the sleeves get pretty thin when doing a 426. i would just call C&D and they will be able to answer your questions.

[xc400ex]

Id recommend a JE or Ross 426 piston 11:1 comp. Use liquid gasket for a base gasket and a stock xr400 headgasket. Given you torque the head down to honda specs exactly you shouldnt have any problems with the studs. You'll be really happy with this for xc. Ive been running this for a while now and its totally reliable no headgasket problems at all. Also when you put the studs back in the cylinder just finger tighten them. When you torque the head it will all tighten into place.