Dr Bass Torque arms causing derailer mis-alignment

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Jun 19, 2011
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1,164
Location
Cheshire, UK
So I have a Norco team Race DH 2004 ish vintage, this is fitted with two Dr Bass torque plates inside the dropouts, the dropout width was 150mm. My Largish hub from devi-motion fortunately fits snuggly being a 135mm dropout with hub. I had it re-laced into a 26" rim from a 28" and the chap who did it made it radially spoked and with no dishing. This has worked well for me for a few years as I never needed to use the low gears due to lack of serious hills and presence of a large motor to assist.
The current situation is that for allowing suspension compression I have a cheap shimano derailleur with a fixed small section of cable keeping the jockey wheels aligned with gear 6. That is I am using the highest gear ratio all the time.

My issue is that because of the spacing effect of putting the thick torque plate on the inside of the dropouts I have reduced the ability of the derailleur to reach the lowest 2 or 3 gears on the freewheel.

My thoughts are that I need to make a spacer to take the horizontal displacement back to where the derailleur could reach those lowest gears. However I am not sure whether there is an easier solution I am missing. I don't want to redo the wheel dishing or remove the torque plates, the wheel rim is dead nuts central between the swing arms.

I have only the largest 44t ring at the pedals so I could do a 3 ring set there but I don't really want 18 gears id be happy with the 6 at the back. plus you get a bigger effect at the back than the front where shifting is concerned.

Any Ideas??
 
I've gone to a single speed for simplicity on my a2b metro but it's more of a tourer with only 38mm rear travel and I tend to ride local bike tracks so it's ideal, the chain line was set for mid gear on a 7 speed freewheel urgh, so I swapped it to single speed 16tooth shimano and run a single cog deraliur as my swing arm has no horizontal bar my chain line allows to be risen a fair bit so I'm 6 links shorter and no gears much simpler.
But I did have the freedom of being able to adjust my hub spacers to get the alignment correct as I've had loads of jobs and lukily I put the metro on hold before ordering spokes so it's allowed me go single speed easier.
 
whereswally606 said:
My thoughts are that I need to make a spacer to take the horizontal displacement back to where the derailleur could reach those lowest gears. However I am not sure whether there is an easier solution I am missing.
Have you already tried the limit screws on the derailer? Sometimes there is enough to adjust that far.
 
I had a look last night. I think without doing any work on it I might be able to get down to the penultimate lowest gear. And I looked at the Dr Bass torque plate more closely and realised it has the bolt holt for the derailleur, however it is behind the Norco's frame-saver dropout. This can be cut and removed to get access to it. however I don't know whether the torque plate hole is tapped and if it isn't whether I can get the tap to do a decent job of tapping it. Pics would help but last night it was so dark that I didn't bother taking any.

I think first I will put a shifter on there and see with it on a stand how low a gear I can actually get before being drastic about it.

Id love to sort it for all of the gears and then I could have this bike on some serious hills without overloading the motor or batteries. Thanks for the input chaps.
 
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