Author Topic: Drive Chain Rubbing  (Read 681 times)

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Offline The Lone Builder

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Drive Chain Rubbing
« on: July 11, 2019, 12:54:10 AM »
While checking over the bike at teh end of yesterday’s run, I noticed this pattern on the chain. It is just the grease that’s come off, there is no metal removal - yet.

Anyone got any thoughts on what ot might be rubbing against? I don’t really want to start taking covers off to try to locate it.
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Offline Erny

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Re: Drive Chain Rubbing
« Reply #1 on: July 11, 2019, 02:51:09 AM »
From picture it looks as right side of chain, check area around front sprocket if it is not rubbing against case
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Offline Kevin D

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Re: Drive Chain Rubbing
« Reply #2 on: July 11, 2019, 04:15:19 AM »
Is the chainguard secure? My own hi mile bike busted the rear mounting tab on the swing arm and the chainguard brace got sliced in two from rubbing. The front chainguard mount held it in place. This part is shown on the K2 fiche but not listed. You may also have the case protector near the front sprocket.
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Offline ekpent

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Re: Drive Chain Rubbing
« Reply #3 on: July 11, 2019, 04:26:15 AM »
 Pretty quick and easy to pop off the countershaft sprocket cover to see if there is any signs of rubbing there like witness marks in the crud and if not work downstream around the chainguard/swingarm/centerstand area.

Offline Mark M

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Re: Drive Chain Rubbing
« Reply #4 on: July 11, 2019, 11:15:31 AM »
The tight curve to the marks suggests something in the vicinity of the front sprocket, it's a tighter radius than the rear.
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Offline bryanj

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Re: Drive Chain Rubbing
« Reply #5 on: July 11, 2019, 12:57:28 PM »
That chain and sproket look orrible and worn to me
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Offline jaytee-nz

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Re: Drive Chain Rubbing
« Reply #6 on: July 11, 2019, 02:40:07 PM »
Check your lower shock mount bolt - if it's too long it could touch the chain as the shock compresses.

Offline Kevin D

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Re: Drive Chain Rubbing
« Reply #7 on: July 11, 2019, 06:55:41 PM »
Quote
The tight curve to the marks suggests something in the vicinity of the front sprocket,

+1 good eye on that Mark M
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71 CB750 K1
104,000 miles
Original Owner
———past———
70 SL100/125/150
70 Candy BlueGreen CB 750 K0
————————————————-
Former Honda parts kid/counter kid/do all
—————————————————————-
Whether you think you can or think you can’t, you’re right
Genius is 99% perspiration, 1% inspiration

Online HondaMan

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Re: Drive Chain Rubbing
« Reply #8 on: July 11, 2019, 07:31:29 PM »
Check for a bent chain guard at or near the engine end of it. It might also be a too-long 6mm bolt there that holds the chainguard onto the swingarm.
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