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finding compression stroke

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Old 05-06-2018, 10:09 AM
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Default finding compression stroke

Adjusted valves yesterday and and timing got all kinds of fubar. got everything timed again or so I thought, but last night laying in bed it occured to me that Even though everything is lined up properly I did not take notice of whether or not I was TDC on the COMPRESSION stroke. No worries I thought Ill check it tomorrow, all I have to do is remove the spark plug for cylinder 1 and stick a chopstick down the hole and watch it rise/fall.....So I got my chopsticks out stuck them in the hole and turned the crankshaft...several times....it doesnt move at all. what gives? am I missing something?

04 cbr600rr
 
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Old 05-06-2018, 11:05 AM
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Just check there is no Dim Sum on the end of the chopstick, and its going through the spark plug hole onto the top of the piston, remember its 2 full turns of the crankshaft to get from TDC to TDC again, have a look at your manual ,timing marks are on the rotor and cover
 
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Old 05-06-2018, 11:13 AM
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Thank you for the reply, I used the all Dim Sum to lube the cams in place of moly, so dont worry. At this point I am all lined up in terms of the TI mark on the crankshaft and the IN/EX on the cam gears, The aligning process is perfect, my concern though is that I aligned everything on the ex stroke and NOT the compression because I lost track of the rotations of the crank shaft/chain position etc. In other words if the crankshaft needs 2 full turns to be at TDC I might need to make another turn of the crank and re-align for it to be correct, and I have no way of knowing where im at, I am asking how do I tell?
 
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Old 05-06-2018, 11:18 AM
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Usually there will be a bigger puff of air out of the spark plug hole on the compression stroke.

As far as adjustment of valves are concerned, the strokes don't matter. Just make sure your checking while the heel of the Cam lobe is over the valve.
 
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Old 05-06-2018, 12:15 PM
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thank you, the chopstick was actually moving.....so as long as the chopstick is at its highest point and im lined up with all my hash marks I should be ok yes?

this is current view does this look ok?

 
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Old 05-06-2018, 02:31 PM
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If it looks like this, with the IN and EX where you have them, with the timing marks set ,and the cam lobes at number 1 cylinder facing in the direction shown, then you have it, but make sure the lobes on number 1 are facing up and outwards
 
Attached Thumbnails finding compression stroke-cams.jpg  
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Old 05-06-2018, 03:17 PM
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thank you for the response, it does, in fact I used that exact diagram from the service manual
 
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