When doing timing belt

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I am now trying to install the Gates T325 belt - and it seems to be a hair too short. Has anyone else had this problem with the Gates? (I believe that I have the tensioner in the position that provides the most slack.)
When I installed mine a few months ago I couldn't get it to line up the timing marks perfectly. One way I was about a half tooth off in one direction, and if I moved it by a tooth then I was off by about a half tooth the other way. I fiddled with it and the cam pulleys for a while to see if anything would budge, and maybe got it just a little closer, it still wasn't perfect, but it was close enough. Its just a little off in the direction where if the belt stretches just a tiny bit over time then it will probably be perfect then.

If that's what you mean by a hair too short, then you're consistent with my experience.

And the bike runs perfectly since I changed it, so no big deal anyway.
 

STraymond

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If that's what you mean by a hair too short, then you're consistent with my experience.
I mean that I can't stretch it to fit over the tensioner: applied to crankshaft gear, left cam gear - then right cam gear. Then even with a lot of tugging - the belt won't go over the tensioner.


Ray
 
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I mean that I can't stretch it to fit over the tensioner: applied to crankshaft gear, left cam gear - then right cam gear. Then even with a lot of tugging - the belt won't go over the tensioner.
Since you didn't mention it, the first question is have you removed the spring? IIRC I got it set first, then connected the spring to the post last, but my middle aged memory is fading on that. The only other thing is that you have to pull it pretty tight between every set of gears, make sure there's no slack at all.
 

STraymond

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Since you didn't mention it, the first question is have you removed the spring? IIRC I got it set first, then connected the spring to the post last, but my middle aged memory is fading on that. The only other thing is that you have to pull it pretty tight between every set of gears, make sure there's no slack at all.
I have left the spring attached - but stretched to its limit and then temporarily tightened the tensioner pulley in the position that provides the most slack. I will attempt to tighten up between the gears - because if I can gain a 1-tooth movement, I should be OK.
 
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I have left the spring attached - but stretched to its limit and then temporarily tightened the tensioner pulley in the position that provides the most slack. I will attempt to tighten up between the gears - because if I can gain a 1-tooth movement, I should be OK.
Yeah, if you're off by 1 tooth that would probably be enough for what you're seeing. Also, since I replaced the spring and tensioner I think I may have held the belt in place and installed the tensioner last. So if all else fails and you're sure there's no teeth to gain, try that.
 

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Just an update: I did finally get the Gates belt on. It turns out that I did not have the tensioner spring at its absolutely lowest (most belt slack) position. I did have to struggle with the Left driven gear in getting the right starting position so that when the belt was pulled tight, the index marks would line up.

Thanks for the help.


Ray
 
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Concerning the tensioner and idler pulleys, can the bearings be replaced instead of the pulley assembly ? I have done this on auto belt pulleys. The bearings were standard sizes.
 
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DeanR
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If anyone is having trouble getting the old belt off, unhook that spring. My tensioner did not reach its bottom position by pushing it downward, until I did this.
Regarding the spring, does it matter from which direction the bottom hook is attached? (as in possible interference withe the belt if the free end is facing outward)
 
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DeanR
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New belt on, tensioner released, 51 teeth between cam marks (as when removed). R cam marks slightly off when others are aligned. Was perfect when removed....Does this look ok?
 

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DeanR
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I guess you went with the Gates t/belt?
yep. Will this position be ok? If not, I don't know how to get all the marks perfect.

I didn't do the three rotations procedure yet but suspect that will not change the alignment of the marks.
 
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ST1100Y

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Will this position be ok?
It will not cause interference, remove the spark plugs and rotate the engine through to ensure there no issues.
I think the offset is caused by a different total length of the t/belt.
 
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Dean that looks exactly like mine did, no matter how I tried I couldn't get that last little bit of mis-adjustment to go away. I think Martin may be on to something that the Gates belt is ever so slightly different in length, but it won't have any affect on how the bike runs. I don't know if the belt stretches a tiny bit as it breaks in, but if it does then the marks will only line up better, not worse, so you have nothing to worry about.
 
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DeanR
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Have done the final procedure of loosening tensioner, rotating crank a couple times making sure all marks are still lined up (or 'almost'), advancing three teeth and tightening tensioner. At that point you can turn the crank as much as you wish before putting the covers back on, correct?
 
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Have done the final procedure of loosening tensioner, rotating crank a couple times making sure all marks are still lined up (or 'almost'), advancing three teeth and tightening tensioner. At that point you can turn the crank as much as you wish before putting the covers back on, correct?
yep, crank away but watch the marks the first couple of revolutions just to make sure.
 

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New belt on, tensioner released, 51 teeth between cam marks (as when removed). R cam marks slightly off when others are aligned. Was perfect when removed....Does this look ok?
Dean, that looks off 1 tooth to me? Per phone call= they should be right on the marks. I have yet to do 1 that was not. Now, they were all Honda belts, That should not make a difference?
If U look at your picture U can see U are off a tooth.
I will try to get up this week. Later BoB

Will bring Honda cam hold tool.
 

John OoSTerhuis

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Dean, if you counted teeth on the old belt and duplicated that during the new belt install the marks should align as before when the tensioning procedure is done. The belt will/should not 'stretch' in use.

Will bring Honda cam hold tool.
Hmmm... whazat, Bob?

Regards, John

via iPhone 4S
 
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