ST1100 timing belt

Mark

Gotta make tracks
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3768
Okay with the help of John O., Adam K, and Martin B's writeups and pictures I changed the timing belt on the '93 yesterday.
Took my time and everything went fairly smoothly (not even a barked knuckle); but, now it's time to start it...
And I have this fear that all *did not go smoothly*... this is an interference engine after all...

so... I need some reassurance, if possible here are the details:
1) the right pully did move when I was fitting the new belt. I moved it back to the original position and kept going.
2) when I rotated the engine (following Clymer instructions for 'seating' the belt tensioner) the engine turned without any problems.

Does 2 mean all is well?

Thanks,
Really!

Mark
 
Double check cam timing marks and if you can manually turn the engine 2 full revs (of the crank shaft) then you should be OK.
 
Thanks Pat,

Clymer instructions had me turn the engine 3 times (2 above) to reset the tension on the belt tensioner; so, I've done that...

I verified that all the marks were were the same as when I started before I did the tensioner setup step.

Mark
 
Mark, if you were able to turn the engine all the way over (running direction) several times without interference and you've triple checked the timing marks and triple checked the idler pulley nut is torqued, you should be good to go.

I know when I changed my belt during my burnt exhaust valve incident, I had the whole top end of the engine apart too. Heavy heart beating, sweat and holding of breath upon first start up were present for sure.

After a bit of rough running at first however, she settled right into her usual sewing machine idle, like nothing ever happened.
 
Boy do I know that feeling you should have come out and helped me with mine to know what to expect. I think I delayed starting mine up after replacing the timing belt for a good day or two as I scoured the manual and forums for info and ideas of how I might have messed something up. Someone recommended leaving the kill switch off when I first hit start quickly to minimize any possible damage, but Jeff is right, if you’ve rotated it with no problems your fine. Mine also took a LONG time to work out it’s idle problems, I was beginning to think I’d messed up something with the carbs. But after getting over my fear of working on the bike myself, doing all that and replacing the coolant hoses, my wife and I just got back from a 3500+ mile trip on the bike and the only problem that came up was with the valve stems.
 
Sure hope that means "tire valve stems"!!!
:)

You are correct. Rear went out just south of four corners on Tuesday, got towed back to Cortez. Wednesday morning with new stem in the rear we took off and 90 miles south of four corners the front tire goes flat towed 130 miles to Flagstaff. Moral of the story??always install supports with your 90 degree valve stems. :(
 
Oh yeah... that would be an *ouch* type of tire valve stem failure... And what *did* your wife say when the 2nd went south? :)
 
I dunno. Buddy of mine and I bent all 16 valves in a Chevy V8 we'd just rebuilt using just the starter. Turns out the timing chain jumped, or we put the cam in wrong, not sure which. Based on that I'm not sure cranking with the starter has any advantage over just firing her up. I wouldn't do either ever again without triple checking everything twice!
 
Oh yeah... that would be an *ouch* type of tire valve stem failure... And what *did* your wife say when the 2nd went south? :)

:) She was actually calmer than me. It was a cooler day, the people at the nearby store were nicer and the wait for the tow truck was only 2 1/2 hours instead of the 4 1/2 from the day before.
 
Mark's a chicken!!!!
Please don't ban me.

(Well really nothing scares me any more... Chris and I have raised 4 kids! :))

But... I did really want confirmation concerning rotating the engine vs. starting it with the starter.
Rotating it 3 times without any obstruction tells me I didn't totally mess it up... I could have missed a tooth (but, doubt it because Chris was watching like a hawk!) and that'd throw the timing off; but, would not kill the valves.

I came to Tucson for a work meeting and it is too hot to ride back to Tempe and back down here for work tomorrow so it'll have to sit until I get back up there now.
 
No, it really doesn't have any effect aside from a bit of mental stress relief. If a valve is going to bend, it'll be bent on the first rotation of the motor whether its by hand or by fire.

I think you can detect a valve contact by hand before you bend it, just go slow and use as short a wrench as possible to reduce your mechanical leverage. Done this a few times before. Also, it's a good idea to remove the spark plugs so the engine is easier to turn over by hand. With the plugs in, not only do you have to expend more effort to turn the engine against compression (reducing your sensitivity to detect a stop), but the crank may rotate farther than you intended and with more force after passing TDC when the compressed air re-expands.
 
Thanks Jeff.
The spark plugs were out (I was following the Clymer manual as well as Martin's writeups) when I turned the engine.
I wasn't using a short handle though... when I do the '01 next week I will be!
 
I've done several of the timing belts, never a problem. The first one was a little stressful tho. :D

In a PM, I said to Mark you will question yurself, easy to get off one tooth. But when it's right, you'll see it, the marks really do line up.
 
In a PM, I said to Mark you will question yurself, easy to get off one tooth. But when it's right, you'll see it, the marks really do line up.

Yup... which made me feel much better because those marks were all where they started.
 
Man, you did this and I did not know about it. I would have brought over some pizza and beer. That would given me opportunity to see someone else sweat out the details as I watched The Master (George) do the delicate operation on The Pig. :rofl1:

:pf1:
 
Man, you did this and I did not know about it. I would have brought over some pizza and beer. That would given me opportunity to see someone else sweat out the details as I watched The Master (George) do the delicate operation on The Pig. :rofl1:

:pf1:

Note to self... Petar would have brought pizza! :banghead::banghead::banghead:

Thanks Petar
 
Go on Mark hit the button, go on, I dare you;):D

:)

I still have to wait until I get back to the bike with is in garage in Tempe...
I can assure you I will be on this thread the moment after I hit the button to let all and sundry know if I was a foolish fellow or not...
 
The ST11 marks make it pretty well foolproof to make sure everything is ok. If you are sure you have follwed all the steps and double checked then things will be fine.
 
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