The bottom end couldn't care less whether it's the exhaust stroke or the compression stroke. The bottom end is just a spindle with a cog on the end. The cog turns the timing chain... What is timing? Timing has everything to do with the top-end, and nothing to do with the bottom end... (so long as you get the T mark on the flywheel lined up).

The flywheel has no idea whether it's on the compression stroke or the exhaust stroke. It doesn't matter to the flywheel. It hits Top Dead Center twice, once on exhaust, once on compression. End of story - there are two TDC's.

When assembling the top end, you want to be on compression TDC, when all valves are closed. It can't be any more clear than that guys.

 

+1. Being on the compression stroke just makes it easier to get the cams timed properly because that's what the marks on the cam drive sprockets are referenced to. Putting your own marks on the sprockets at the top of the exhaust stroke is just unecessary work.

 

Now I'm not talking bikes I'm talking multi cylinder engines and yes it matters when you have multi coil packs and multi crank and cam triggers timing and valve relations do matter.

 

Yeah not to be a buttface, but I hope somebody reading this thread thinks they can work on the timing of an automobile and use any ol' piston position at "up" as "top dead center" and see how well that works out.



I'm leaving this thread. All relevant information was sucked away like two pages ago :-)

 

lol...well I guess I should have said, Yup it 180 degrees out, but as long as you put it back together at 180 out you're fine.....it's a thumper. lol


Five pages on this thread.....is it cold up North or sumthin.....don't tell me we are already entering that stir crazy phase, where all you Yankees get cabin fever.

 

Its been raining cats and dogs since about noon down here. We HAD a wicked sweet group of guys lined up to ride trails with us tomorrow (well, today now, Saturday) but they all bailed since even if the trails aren't closed, they're gonna be a gigantic mudhole disaster. IDK if we're even gonna bother to ride 'em. Might dualsport around the camp instead.