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More chain noise with 13T sprocket

7K views 22 replies 11 participants last post by  pooder7 
#1 ·
Anyone notice this? I have my chain tension at the factory 1 inch.
 
#2 · (Edited)
I didn't notice any difference with the 13T sprocket in terms of noise. FWIW, I always wear silicone ear plugs when I ride. If you already had a lot of miles on your chain when you switched to a new 13T sprocket, that might account for it. A drive chain that is even slightly stretched will "click" as it rolls over a new sprocket.

I think 1 inch of chain slack should be considered the minimum amount... I run mine at 1.25 to 1.5 inches. Make sure you are lubing the chain periodically as well... a dry chain can be noisy compared to one that is regularly lubed.
 
#3 ·
Ok I don't ride with earplugs since I'm typically less than 55mph. My bike has only 2400 hundred miles so doubt its a stretching issue and I lube every 400-500 miles. Lubed after I installed the sprocket actually.

I'll try loosening the chain maybe that will quiet it down.
 
#5 ·
when you tighten the chain , make sure someone is sitting on the bike or some weight on the bike ... if you tighten the chain without any weight on it , when you do sit on it and ride , that 1-inch will not be there and the chain will be too tight ,, therefore making a noise like is too tight


not sure if you did have some weight on the bike when you tighten it or if this has already been suggested :)
 
#6 ·
when you tighten the chain , make sure someone is sitting on the bike or some weight on the bike ... if you tighten the chain without any weight on it , when you do sit on it and ride , that 1-inch will not be there and the chain will be too tight ,, therefore making a noise like is too tight

not sure if you did have some weight on the bike when you tighten it or if this has already been suggested :)
The recommended chain slack / adjustment does not require another person sitting on the bike - not sure who told you this, but it's not correct or necessary.

1.5" of slack is definitely more than Honda recommends - the exact specs are in the manual - .8" to 1.2" to be exact.

I keep mine at 1", checked / adjusted when the chain is cool (not after a ride - important).



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#7 ·
Follow what it says in the user manual to adjust your chain. It usually tells you to do it on the side stand, or centre stand (if your bike has one). The reason for the slack is that it gets taken up when the suspension compresses. Once the swinging arm is past the point where the centre of the axis of the sprocket, swinging arm and rear wheel line up, it starts to slacken again. It's always better to err on the slack side if you are unsure, a tight chain will damage your sprocket shaft bearing, which will cost a lot of money to replace. Also, check the chain in a few different places, it can be slack in one place and tight in another. By this, I mean move the bike forward and backward, or if your bike's on a stand, move the back wheel round to a few different positions and re-check. Always adjust your chain before you ride the bike, when it's cold. When your chain's hot, after a ride, it's longer. ;)
 
#10 · (Edited)
The reason for the slack is that it gets taken up when the suspension compresses.
True


Once the swinging arm is past the point where the centre of the axis of the sprocket, swinging arm and rear wheel line up, it starts to slacken again.
Not true... when the front countershaft, swing arm pivot, and rear axle are in alignment with each other, the drive chain will have its maximum amount of slack. From there, the slack will continue to progressively decrease, right to the point where the rear suspension has bottomed out. It won't become slack again, until the swing arm returns to the position where rear axle is in alignment with both the counter shaft and swing arm pivot center lines. In effect, as the suspension compresses, the front of the swing arm creates a third point of contact for the chain, and is the reason for the plastic chain guide which wraps around the top and front of the swing arm and along the underside.


It's always better to err on the slack side if you are unsure, a tight chain will damage your sprocket shaft bearing, which will cost a lot of money to replace. Also, check the chain in a few different places, it can be slack in one place and tight in another.
Good advise...adding to that, the drive chain should be adjusted to the recommended spec relative to where the chain is the tightest... which means that even if you adjust the tightest spot to just 1.0" slack, you could ultimately end up as much as 1.5" of slack in the places where it is loose.
 
#8 ·
I'm with MotoMike. I adjust the street bikes to 1.25 inches slack at the tightest point (your have to rotate the chain and try 8-10 places) and the enduros to 1.5 inches.

A too-tight chain is not kind to the counter sprocket or the transmission.
 
#9 ·
The chain noise is not super loud but I can hear the louder "whurr" or however you describe it. It does only make the sound when on light throttle, on deceleration its not noticeable. Heavy throttle the exhaust is too loud.

The chain does drop more to go over the smaller sprocket and run across the guide alot more if that has anything to do with it. I'll try going to 1.25" slack tomorrow. Also I adjust my chain on a rear stand when cold.

Anyways thanks for the input everyone. I'm not too worried about it the bike runs great really enjoying the extra 6th gear acceleration!
 
#18 · (Edited)
I understand what you are saying Wynne, the distance between the sprockets shortens as the suspension compresses, and so the upper run of chain becomes slightly shorter between the sprockets... However, the distance between those same two sprockets has increased by a greater amount for the lower run of chain as the suspension compresses. The net effect is that the chain becomes tighter as the suspension compresses.

The idea that you are putting forth, that the chain becomes more slack as the suspension compresses is simply not true... if it were true, Honda would have us adjusting the chain with little to no slack when the suspension is in its unloaded state.

Once again, as the suspension compresses, chain slack decreases. Period.

Still don't believe me? Here's Aufitt's quote: "My Manual says 'Do not ride your motorcycle if the slack exceeds 50mm... So I run 49,9999mm. When I pull the suspension down this soon becomes 20mm or less. If you run 25mm its way too tight."
 
#20 ·
Sorry if I wasn't as clear as I could be, I have problems getting my thoughts into words sometimes. What I mean is that the chain does become tighter as the suspension compresses, up to the point where all 3 axes of front sprocket, swinging arm pivot and rear axle are in line. Once the suspension is compressed beyond this point, the chain starts to slacken again. I hope this makes sense. ;)
 
#19 ·
You are both right, but at different parts of the stroke.
But to keep it simple (and not confuse new riders) we need slack everywhere in all situations.

Honda recommends it so tight as the service intervals might be 12,000km till the bike see's a Honda Technician again so they cover their ass that way.

The most common new rider mistake is to keep tightening to the lower limits,
by the time they've adjusted their chain twice its rooted and got more stretchmarks than Jessica Simpson.

Many are under the misconception that the chain slack = snatchiness,
the exact opposite is true, a loose chain smooths out the drive.

Ive finished grueling wet muddy 2 day enduros with 4-6 inches of chain slack as the bikes are impounded in parc ferme and sometimes you dont even get 30 secs to adjust it.
 
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