Author Topic: camshaft timing  (Read 759 times)

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Offline remi

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camshaft timing
« on: October 14, 2018, 09:00:55 PM »

hello, i'm Remi i live in canada and i just had a 77 500 xs.
I have always been passionate about this model and I was lucky to find one

 following a head rebuild it's impossible for me to time up the engine, i explain: i respect all the steps of the owner manual, put the left piston at the top, then go on the  "V" Mark and assemble the camshaft marks with the mark of the caps. but from the first turn of the engine (by hand) the left piston hits the intake valve. I do not understand what is going on, one of you has already encountered this problem.
please excuse my english this is not my first language

Offline guylr

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Re: camshaft timing
« Reply #1 on: October 14, 2018, 11:01:11 PM »
Welcome Remi. Were the governor assembly and or the breaker shaft removed during this repair? If so are you certain that the breaker shaft was timed correctly and the governor assembly assembled using the locating pin?  If those are correct the can timing should follow just as you described.

Guy
Now Retired Yamaha guy. Cut me and I bleed "Cinquasia Red"

Offline remi

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Re: camshaft timing
« Reply #2 on: October 15, 2018, 02:58:21 AM »
thanks you  for your reply,

 i bought the bike as it with a fresh head just rebuild.  the cranckcase dont seems to be allready open so i dont thin the breaker shaft has  been touch, but  The governor has been mooved i guess, because the paint-lock on the screw have been brock.
First should i try to time the governor ? don't you know how to?
best regards

Remi

Offline guylr

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Re: camshaft timing
« Reply #3 on: October 15, 2018, 03:40:00 AM »
The pointer must be reset to align with the T left mark when the left piston is exactly at top dead center. You will need either a dial indicator or a piston stop tool to find TDC.

Guy
Now Retired Yamaha guy. Cut me and I bleed "Cinquasia Red"