2022 V4 PP, single sided swing arm. I fitted new chain and sprockets at the start of the year plus cush drives. The chain (DID) has done around 2K so far and had been faultless. Before I went out today I checked the tension, it was a tad on the loose side so left it as was. 100 miles back home and the chain is now bow tight and making a horrible noise due to the tension. Not tight in one spot, uniformly. I checked the two pinch bolts, both tight. I did slacken them off and the chain adjuster is working fine in both directions (to tighten and loosen). The chain is running fine, now adjusted, with no tight spots evident. Wheel spins fine and sprockets are solid. I can’t see any way for the adjustment to go out so badly. Any ideas?
Going on what you've said, and apart from unusual sudden play or movement in swingarm pivot/rear axle this is a total head scratcher.
Can the torque from the engine turn the adjuster? It effing hot. Maybe the swing arm heated up and expanded and then moved when you gave it a bit of stick.
On the 2010 Multi model, the difference in chain tension between when the chain is hot and when it is cold can be up to 8 mm, due to the expansion of the single-sided swingarm. Check it right after riding (when it's hot) and the next day (when it's cold)
Is it possible you checked the chain in different modes? Changing modes effects the ride height which in turn effects the chain tension. I think you’re supposed to check the tension in Sport mode but you’ll have to check in the manual, I’m not 100% sure.
I know on my Multistrada 1200 you had to be in a specific mode & Suspension setting when adjusting the chain.
Thanks for the help I appreciate that the bike needs to be on its side stand and no load on the bike to check chain slack. Different modes might make a minor difference. When I checked it before the ride it was a cursory check "yep, it's a bit loose but will do for today ". When I got home it wasn't tight, it was proper red face tight. Different modes or hot swing arms shouldn't make that much difference. I'm just about to start taking things off
if it is possible that you are able to adjust a chain in one mode so that the chain would be too tight if another mode were selected, then the handbook or technical manual procedure should include paramount clarity to explain this, as it's such a safety critical area.
I know in my manual for the 1200 with leccy Ohlins the bike had to be in a specific mode for chain adjustment. @nelly may be able to clarify?
Example: Multistrada 1200 S Öhlins In this state, with 63 mm of compression (out of 170 mm of total travel), the chain is at its tightest. Once you’ve done this for your specific model, you’ll have the correct chain tension setting
It looks like my issue is heat related as suggested by aero . Previously with the original chain and sprockets I'd set the chain slack to the minimum and ride for 2K miles before even thinking about adjusting again. It always looked ok, hot or cold. At the end of last year I fitted a JT rubber mounted front sprocket, Supersprox rear and heavy duty DID chain. However, all my early rides were in the cold (very). I noticed the chain being too tight on my first ride with ambient temps of 24c. I spent the whole day stripping the rear hub out (see filthy hub thread) set the chain and went for a ride. Guess what, no different! Ended the ride with a tight chain. I adjusted the chain back to minimum slack while everything was hot. Checked it this morning now it's cold and it's at least 5mm past the suggested maximum slack. That's gone from 27mm to 34mm of slack hot to cold. I'm gobsmacked. I'm only going to adjust the chain when it's hot in future. I'm wondering if the combination of the new chain and sprockets is exasperating the problem. At least I know nothing is failing. Thanks for the help
I don't trust the elaborate tension checking techniques in manuals. My bike is always in sport anyway and then I lean on the seat compressing the suspension until the swinging arm is horizontal and the chain under the greatest tension. If there is half an inch of slack it's fine. It you can play a tune on it, it's too tight. Edit: I check for tight spots when on the stand cleaning and lubing though.
I'm glad that @aero posted this. It's the only way to really understand what the suspension/chain relationship is, so you can make your own judgement. However, a lot of people won't understand this geometry which is why the handbook gives you a simplified 'on side stand', etc setting.
Remove the 2 pinch bolts, clean them and the threads in the the holes. Apply grease b to the bolts, re torque to 35nm. My chain was doing the same, this fixed it.
