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Discussion Starter · #1 ·
Hey guys,

I have a 1977 Suzuki gs750 that is almost done.

Ive turned the thing from a pile of junk to an amazing café racer.

Recently, my motor was rebuilt (pistons, rings, etc) and it is quilty work done by a person who knows a bunch about old bikes.

Yesterday, I went to kick start my bike for the first time and the lever went down half way then stopped. now it wont kick anymore....

The guy who rebuilt and timed my motor thinks that he timed it wrong.... I am wondering if any of you know the timing for my motor. Please help!
 

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Sounds like the quality work done by your person who knows a lot about old bikes wasn't quite the quality you expected.:wink:

Cam timing is a complex thing on 4 cylinder, overhead cam engines. Normally, the number one cylinder is placed at top dead center and then the camshaft or sprocket is aligned with the stamped timing marks that all OHC engines have. When the camshaft (S) are put into the correct position, the intake and exhaust valves on the #1 cylinder will be closed and your feeler gage will slide in to adjust that cylinder.(no pressure on the valves for that cylinder)

Now, I can't imagine that your rebuilder didn't at least spin the engine over after the rebuild?

Here's the bad part: If the cam timing is off, the valves will or may come into contact with the pistons, potentially bending them and possibly destroying the piston and even bending the rods. If the cam chain slipped off of the sprocket that turns it, this would keep your engine from turning over and can damage the engine in a heart beat. Here's how to proceed:

Take the spark plugs out so the engine is easier to turn over. Take the valve cover (S) off of the top of the engine, exposing the camshaft (S) and remove the camshaft drive sprocket then grab the chain and use it to turn the engine over. If it turns over, then the chain is on the lower drive sprocket:biggrin:

Then, ascertain if the #1 cylinder is at top dead center by using a timing mark or a dowel in the spark plug hole, which is easier. Then align the top camshaft drive sprocket with the stamped timing marks on the cylinder head---but make sure that the cam itself is not pushing the valves down. Some cam drive sprockets can only be attached to the camshaft in one way because of a dowel pin that locates the sprocket and cam correctly and if this is so on your engine then once the #1 cylinder is at top dead center and the camshaft/ sprocket marking are aligned, then your engine is timed correctly. Then, try the kickstarter and slowly turn the engine over. If it easily does so then use the electric starter to turn it over a bit, then put the plugs back in. I assume your pro adjusted the valves??? If not (Ask him) then this is another topic for discussion.

Find a Suzuki GS forum and ask questions there also.

Sam:coffeescreen:

If you have anymore questions, don't hesitate to ask.
 

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Discussion Starter · #3 ·
Thank you!

Thank you so much for your very well written and thorough answer.

I forwarded your response to the rebuilder. I hope he can get it fixed. He timed my motor 20 links from mark to mark on the cams.

He seems to think that my manual gave him fault information.... I think that he just rushed through it. And for the record, he didn't roll the motor over after hooking up the chain. He's a crust old guy who considers me an annoyance. Plus, he is cocky....

Lets hope he can figure it out this Saturday.

I will keep you posted.
 

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Valve timing on Suzuki engines of that era require counting links, and it's very easy to miscount. It's much more likely that your mechanic miscounted than the manual published a mistake of that magnitude. Manuals do contain errors, but that would be a big one.

Even if it did, you always roll the engine through a couple times, like you said.

I have a lot of respected for bearded old guys, but he sounds like he's too busy to work with you.
 

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Thank you so much for your very well written and thorough answer.

I forwarded your response to the rebuilder. I hope he can get it fixed. He timed my motor 20 links from mark to mark on the cams.

He seems to think that my manual gave him fault information.... I think that he just rushed through it. And for the record, he didn't roll the motor over after hooking up the chain. He's a crust old guy who considers me an annoyance. Plus, he is cocky....

Lets hope he can figure it out this Saturday.

I will keep you posted.
Well i'm here to answer your questions. Maybe if people didn't rush, bug, or expect someone that was here to guide someone on how to work on there own bike to drop everything to work on nothing but there bike when they deem fit things would get done.

After reading this I feel that maybe its in your best interest to come and pickup your bike, and take it some where else.

From The Crust Old Guy whos Cocky -- WIFE

:(
 

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Whea bes de cocky od crust from de sticks or deliverance gas staton? He be sounded edumicated and ob sound minde. I sho bees tekin my scoot to hes place tamarra.;)

Sam:coffeescreen:
 
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