Timing mark

discussion about the 750 Sport and '89/'90 900SS, which share many mechanicals with the Paso series
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Maico88
Posts: 73
Joined: Sun Oct 05, 2008 1:32 am
model: 750 Sport
year: 1990
Location: Georgia, USA

Timing mark

Post by Maico88 »

I decided to check my valve clearance since I have not done so since I got the bike. I would like to know if there is more than one mark that can be observed through the sight glass on the alternator side of the engine. I have pulled the timing belt covers and when the cam timing marks are lined up there is a drilled hole visible through the sight glass. Is that drilled hole TDC and is there more than one mark (I have found only one)? Thanks.
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paso750
paso grand pooh-bah
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Joined: Sun Jul 18, 2004 12:00 am
model: 750 Paso
year: 1987
Location: southern Germany

Re: Timing mark

Post by paso750 »

there are a total of 8 marks on the flywheel. 2x TDC, idle firing, full advance and two reference marks for the pick-ups.

G.
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Maico88
Posts: 73
Joined: Sun Oct 05, 2008 1:32 am
model: 750 Sport
year: 1990
Location: Georgia, USA

Re: Timing mark

Post by Maico88 »

Thanks for the info. I was able to determine that there is more than one mark Unfortunately, they all look the same. I checked the valves on the rear cylinder with it at TDC and the front cylinder at rock point. Same with the valves on the front cylinder, that is with the rear cylinder at rock point. It appears that one valve (rear exhaust) is correct and the rest are tight on the opening rocker and loose on the closing rocker. Does this sound reasonable?
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ducbertus
paso grand pooh-bah
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Joined: Sun Jan 07, 2007 12:00 am
model: 907 I.E.
year: 1991
Location: holland

Re: Timing mark

Post by ducbertus »

Hi Maico 88,

this sound normal. often the closers are not set properly, resulting in bouncing valves while landing on the seat. this causes slightly deformation of the valve seat and the valve moves further outside towards the opener rocker.
try to get the closing rocker close to zero. the bike runs more quiet and needs less adjusting. don't forget to check the play annually.

Bertus
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Maico88
Posts: 73
Joined: Sun Oct 05, 2008 1:32 am
model: 750 Sport
year: 1990
Location: Georgia, USA

Re: Timing mark

Post by Maico88 »

Thanks. Guess I will get busy measuring and order shims.
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