Chain alignment issue on MTB
#1
Thread Starter
Junior Member
Joined: Jun 2020
Posts: 21
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Chain alignment issue on MTB
Hi All
I am after some advice as I am having issues with my newly built hardtail. I have fitted a single narrow/wide chain ring (42T) up front paired with an 11 speed cassette on the rear. Fitted correct 11 speed chain and have a shimano deore xt derailleur.. The crank has all spacers on left hand side to bring chainring as close to frame as possible.
I set up the derailleur as far as end point travel is concerned prior to fitting the chain but now I've fitted chain I am major alignment issues resulting in chain being pulled off. It seems ok in gear 11/10/9 but as soon as it gets to 8th gear the chain is so out of line with the chainring it pulls chain off (chain ring too far out from frame. The obvious solution I guess would be to move crank spacers but they are already all on the left hand side meaning the chainring is already as close to frame as possible.
Now I will say that when fitting cassette I had leave the spacer nearest to the wheel hub out to enable to 11 speed to fit on hub, I guess this is normal...
Any help appreciated
I am after some advice as I am having issues with my newly built hardtail. I have fitted a single narrow/wide chain ring (42T) up front paired with an 11 speed cassette on the rear. Fitted correct 11 speed chain and have a shimano deore xt derailleur.. The crank has all spacers on left hand side to bring chainring as close to frame as possible.
I set up the derailleur as far as end point travel is concerned prior to fitting the chain but now I've fitted chain I am major alignment issues resulting in chain being pulled off. It seems ok in gear 11/10/9 but as soon as it gets to 8th gear the chain is so out of line with the chainring it pulls chain off (chain ring too far out from frame. The obvious solution I guess would be to move crank spacers but they are already all on the left hand side meaning the chainring is already as close to frame as possible.
Now I will say that when fitting cassette I had leave the spacer nearest to the wheel hub out to enable to 11 speed to fit on hub, I guess this is normal...
Any help appreciated
#3
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Joined: Feb 2012
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From: Rochester, NY
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Have you measured the real chain line amounts of both the cassette and the chain ring? Andy
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AndrewRStewart
AndrewRStewart
#5
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Joined: Feb 2015
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From: Mission Viejo
Bikes: 1986 Cannondale SR400 (Flat bar commuter), 1988 Cannondale Criterium XTR, 1992 Serotta T-Max, 1995 Trek 970
The object isn’t to get the chainring as close to the frame as possible. You want to have it line up in the middle of the cassette.
I’m not sure of your 11/10/9/8 issue. The chainline would get worse as you go to the 1st position, but I’m having a tough time understanding how a chainring would be that close and not hit the chainstay and have problem only 4 cogs over.
John
#6
Senior Member

Joined: Jan 2017
Posts: 1,245
Likes: 162
You need to provide more details. What kind of BB, shell, crank, chainring, what type of spacers, on the spindle or the BB, which type of spider, which side of spider, dropout width, measured chain line at the chainring, etc.





