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Discussion Starter #1 (Edited)
Hi!

Thanks to:

http://www.600rr.net/vb/showthread.php?t=60098

and

http://www.600rr.net/vb/showthread.php?t=241983

(amongst other threads..)

I managed to adjust my valves back within spec. Something has been bothering me since initially setting TDC to check the valves though. When aligning the 'IN' and 'EX' marks with the cylinder head cover, the 'T' itself lines up with the notch in the timing hole. Not the '|' index mark next to the T.

When setting TDC according to the '|' index mark, the 'EX' mark hovers about 2-3mm above the cylinder head cover. The 'IN' mark about 2-3mm below. This seems too little of a difference to adjust by adjusting the cam sprockets one tooth up the chain. They are in sync towards each other though. By turning the crank just a tiny bit further clockwise they neatly line up flush with the top of the cylinder head.

Could this 'minor' but still very noticeable difference be caused by worn components? While adjusting the valves the bike got a spanking new OEM CTT. During disassembly the cam sprockets and chain have been marked, and put together exactly the same way.

As a guess this 2-3mm offset on the cam sprockets might be too much to be adjusted by adjusting the chain one tooth on the cam sprockets. The notch would then probably line up wit the dotted index mark instead. But the crank sprocket is much smaller. Could this offset be the result of the bike being switched off, in gear, moved backwards? I've read that the slack on the non-CCT side could then cause the chain to skip a tooth on the crank sprocket.

Here are some pictures:
IMG_2492.jpg
IMG_2495.jpg
IMG_2496.jpg
IMG_2497.jpg
 

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mine is also similar, when i align the "l" on the mark on the cover the intake & exhaust timing marks do not sit flush with the surface of the cylinder head, more so if you had the head & cylinders milled for more compression, what i did was i checked the lobe centers when i had the engine off the frame & they both were retarded compared to the manual specs so i simply slotted the bolt holes in the cam sprockets & adjusted the timing.
 

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Discussion Starter #3
mine is also similar, when i align the "l" on the mark on the cover the intake & exhaust timing marks do not sit flush with the surface of the cylinder head, more so if you had the head & cylinders milled for more compression, what i did was i checked the lobe centers when i had the engine off the frame & they both were retarded compared to the manual specs so i simply slotted the bolt holes in the cam sprockets & adjusted the timing.
Thanks for your feedback!

What do you mean by 'slotted the bolt holes in the cam sprockets'? I will do some more research on timing adjustment, thank you.
 

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Thanks for your feedback!

What do you mean by 'slotted the bolt holes in the cam sprockets'? I will do some more research on timing adjustment, thank you.
you take a carbide burr & a die grinder & cut the bolt holes by elongating them so you can adjust the camshaft clockwise or counter clockwise to change the timing.
 

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Discussion Starter #5 (Edited)

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I'll revive this thread for information purposes or if anyone can comment further. I experienced the same thing as OP when I adjusted my valves. My cam sprockets line up perfectly when I set the crank to "T". There is no way adjusting the cam sprockets another tooth would fix this.

Is "T" suppose to be TDC or is "|" suppose to be TDC???? The service manual text says to align "T", however in the picture it points to "|" :ponder:


Here it is lined up with "|" according to the service manual:


Here it is lined up with "T"
 

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It should be aligned to the "|", when i was checking actual crankshaft TDC when i was rebuilding the engine, the "|" mark showed the closest to TDC using a dial indicator gauge & degree wheel, the "T" is off a couple of degrees.
 

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It should be aligned to the "|", when i was checking actual crankshaft TDC when i was rebuilding the engine, the "|" mark showed the closest to TDC using a dial indicator gauge & degree wheel, the "T" is off a couple of degrees.
Good to know since it's a little ambiguous in the service manual. I guess my marks are just a tad bit off when aligned to the "|" mark if you view the cylinder head exactly at eye level. So as-is, is this the best I can get the timing without altering parts?
 

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Good to know since it's a little ambiguous in the service manual. I guess my marks are just a tad bit off when aligned to the "|" mark if you view the cylinder head exactly at eye level. So as-is, is this the best I can get the timing without altering parts?
yes, i think that's about as close you can get to zeroing in the timing marks, these are mass produced items so they will be off most of teh time, even the R6 engine i'm building the timing marks on the crank pulse rotor & cam sprockets are off, you can't trust them if you want to degree your cams accurately.
 
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