donkeypuncher Posted January 22, 2011 Report Share Posted January 22, 2011 what up fellas. so i just got done puttin my new top end on my bike after installing a 4mill crank and i now have a little problem. when i turn the motor over, as the piston reaches tdc the top ring goes past the top of the cylinder and gets stuck making it impossible to turn completely over. makes me think i need to run a spacer plate at the bottom of my cylinders to fix this but, i thought having my domes cut for the longer stroke meant i wouldnt need a spacer. also, if i run a plate after having my cylinders ported for the longer stroke won't it throw the port timings and what not off? and im not sure if it matters but i'm running stock pistons (cylinders are on stock bore). only thing i can think of is either i do need a spacer plate and just misunderstood when you do or don't need to run one or my crank isn't really a 4mill crank.....? any ideas? Quote Link to comment Share on other sites More sharing options...
Bruce_Blaine Posted January 22, 2011 Report Share Posted January 22, 2011 (edited) What pistons are you running? Edited January 22, 2011 by Bruce_Blaine Quote Link to comment Share on other sites More sharing options...
donkeypuncher Posted January 22, 2011 Author Report Share Posted January 22, 2011 What pistons are you running? right now i have the stock pistons in. but i think i just figured it out. i think i need to buy pistons made for the longer rods my 4mill crank has. Quote Link to comment Share on other sites More sharing options...
Bruce_Blaine Posted January 22, 2011 Report Share Posted January 22, 2011 (edited) right now i have the stock pistons in. but i think i just figured it out. i think i need to buy pistons made for the longer rods my 4mill crank has. Yeah, the pistons you need have an offset. Edited January 22, 2011 by Bruce_Blaine Quote Link to comment Share on other sites More sharing options...
BigRed350x Posted January 23, 2011 Report Share Posted January 23, 2011 You need 795 series Wiseco pistons. They have the wrist-pin location off-set for the longer rods. Quote Link to comment Share on other sites More sharing options...
BANSHEE HP Posted January 23, 2011 Report Share Posted January 23, 2011 a 795 seris piston has a 5mm pin offset, to accomodate for the 5mm longer rod. Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted January 23, 2011 Report Share Posted January 23, 2011 even with the rite pistons they will stick out ,so you need a rechambered head or a cut dome Quote Link to comment Share on other sites More sharing options...
donkeypuncher Posted January 23, 2011 Author Report Share Posted January 23, 2011 even with the rite pistons they will stick out ,so you need a rechambered head or a cut dome yeah, i have custom cut domes. Quote Link to comment Share on other sites More sharing options...
Darthwall Posted January 23, 2011 Report Share Posted January 23, 2011 you can also run blaster pistons in it if the dome will let you and your at a 66+mm piston they have a different degree dome and is said to make more power Quote Link to comment Share on other sites More sharing options...
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