Easiest is to get a mech dropper, also known as a derailleur hanger extension.
What is the maximum tooth sprocket you could fit on the back using a Deore DX rear derailleur?
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Where did you get 34T as the max sprocket from, most early 90s mech with the SGS super long cage had 32T as the max and a 34 was the stretch.
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Ah, had a quite reread, this the modern XT mech M771?
That's probably more try to life when things had to be more accurate.
Forget the B-tension, it designed for tweaking to the top cog to get a close as possible for the best shifting. There is only so much distance it can make.
Everything you do to distance from the top cogs makes everything worse for every other cog, especially the smaller cogs.
That's probably more try to life when things had to be more accurate.
Forget the B-tension, it designed for tweaking to the top cog to get a close as possible for the best shifting. There is only so much distance it can make.
Everything you do to distance from the top cogs makes everything worse for every other cog, especially the smaller cogs.
retrobiker273891
Retro Guru
What does 'try to life' mean?
I have been working on it again today. I did manage some more clearance by doing the reverse b-screw trick. I actually found a couple of even longer bolts/screws which fit that thread in the garage. I tried one much longer than the original but it actually doesn't provide any benefit past a certain point as the extra length just goes beyond where the little lip catches the screw so length then becomes moot.
I had better improvement by taking the derailleur off and screwing the original in the other way. The got me a bit more clearance.
There is still the little rattle but only on the lowest gear. I went for a ride and the functionality does not seem to suffer.
When I got it back and lifted the wheel and pedaled I noticed there is no sign of trouble when it is going that direction. That rattle only happens when reverse pedaling and how often will that happen when riding? Almost never. I also do not see any issues when free wheeling either. So I may just let sleeping dogs lie with that.
On the other hand I have been having a terrible time trying to get the gears to index. They weren't right even before adding this new cassette but the issue then was that it is a 9 speed shifter and the old cassette was 8 speed.
Now with this new one, it is a lot better, in that I can change to all gears but I am unable to get proper indexing for all gears. Was trying for hours and still could not get it right. I can either have indexed low gears and jumping or unusable bottom gear or two or vice versa. I was fiddling with the adjuster for so long with tiny increments and could find no way for them all to be right. It will either be a shade too tight for low gearing to work and they jump around or a shade too slack and am unable to shift out of highest gear without double clicking or when shifting into higher gears several jumps at a time.
I was able to fine tune it so that everything seemed right for the 32t chainring but then when I shifted to the 20t the low gears were out again. That meant I had to slacken the wire a bit for them to work and then the high gears would be out. I, of course, chose indexed low gears for now as those are the ones I use most.
Not sure of a way around that? Made me suddenly want to say screw it and get thumb shifters! If I don't find a remedy that may well be what I do as indexed shifting is more trouble than it is worth if I don't find a way to fix it.
With all that said the lower gearing is great! 14 gear inches feels just about right! I also had more to play with on the middle ring. I didn't have to go into the lowest much on that little ride out but felt I had plenty more in reserve with those 2 extra low gears of 32 and 36. Haven't had chance to try on the meaner hills yet.
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bold stelvis
Kona Fan
@retrobiker273891
I would check your rear shift cable is clean and isn't taking any tight bends on any of the outers
oftentimes poor index shifting is just cos of a crappy cable setup introducing some variability
the other thing this may be a symptom of is a bent derailleur hanger (if its a steel frame it can be bent back fairly easily if so)
even slightly bent out of straight might introduce some variability to the shifting - of your don't have the right gauge to check might be one for the LBS to take a quick look at
this is all given your cassette, shifter are both 9 speed and the RD is 'old shimano' pull ratio (which I believe the RD_m771 is)
I would check your rear shift cable is clean and isn't taking any tight bends on any of the outers
oftentimes poor index shifting is just cos of a crappy cable setup introducing some variability
the other thing this may be a symptom of is a bent derailleur hanger (if its a steel frame it can be bent back fairly easily if so)
even slightly bent out of straight might introduce some variability to the shifting - of your don't have the right gauge to check might be one for the LBS to take a quick look at
this is all given your cassette, shifter are both 9 speed and the RD is 'old shimano' pull ratio (which I believe the RD_m771 is)
bold stelvis
Kona Fan
chainline would be the other thing to look at (ie in the middle chainring the chain should be pretty straight straight with the middle of the cassette cogs
also - you are using an 9 speed chain? (or a 10 spd would work fine also) an 8 speed is a fraction wider and might be getting fouled between the cogs a little given the tighter spacing on 9 speed cassettes
also - you are using an 9 speed chain? (or a 10 spd would work fine also) an 8 speed is a fraction wider and might be getting fouled between the cogs a little given the tighter spacing on 9 speed cassettes
bold stelvis
Kona Fan
lastly - the more you try and push your setup (massive B screw adjustments, mega wide range, pushing the RD further than spec, etc) then the more I would expect shifting to get worse.
yes shimano's specs for RD max teeth and capacity are 'conservative' and many (including myself) tend to try pushing these a bit but I suspect you are pushing them in multiple places - and whilst it CAN work, if you want 'nice' reliable shifting might be more sensible to stay in spec
I think you have obvious tendency to be overly analytical about what you think you need, and just jump to pushing everything to the max, but I would echo some advice you've already had which is to just get a bit fitter and stress less about trying to push into ultra low (even for loaded touring) gear ranges
yes shimano's specs for RD max teeth and capacity are 'conservative' and many (including myself) tend to try pushing these a bit but I suspect you are pushing them in multiple places - and whilst it CAN work, if you want 'nice' reliable shifting might be more sensible to stay in spec
I think you have obvious tendency to be overly analytical about what you think you need, and just jump to pushing everything to the max, but I would echo some advice you've already had which is to just get a bit fitter and stress less about trying to push into ultra low (even for loaded touring) gear ranges
bold stelvis
Kona Fan
one more point - getting an older RD to clear a 34T is pretty common and tends to work (even with the roadie ones in my experience)
I'm not sure the same logic applies to a newer model like the RD-M771 and a 36T - it might be shimano just wised up a bit on the specs and there is less room for going bigger -
it wasn't really until saint and the 10 speed MTB dynasys groupsets that shimano really changed much about the essential geometry on the derailleurs - despite changing aesthetics there isn't really much difference between and M650 6 speed and and M750 9 speed in terms of the basic geometry
I'm not sure the same logic applies to a newer model like the RD-M771 and a 36T - it might be shimano just wised up a bit on the specs and there is less room for going bigger -
it wasn't really until saint and the 10 speed MTB dynasys groupsets that shimano really changed much about the essential geometry on the derailleurs - despite changing aesthetics there isn't really much difference between and M650 6 speed and and M750 9 speed in terms of the basic geometry
11-40 with an ‘95 LX
On my ride today I played around with her. Going up a short steep section I normally do in 22/27 (equivalent to the original gearing) I used 11/40. Worked great.
Tonight on the stand I heard some noise. I have the B screw all the way in and it’s marginal. I had bought some derailleur extentions so threw one on. They work. I still have to figure out how to orient the extension.
Before and after (pardon the filth it’s a working bike)
On my ride today I played around with her. Going up a short steep section I normally do in 22/27 (equivalent to the original gearing) I used 11/40. Worked great.
Tonight on the stand I heard some noise. I have the B screw all the way in and it’s marginal. I had bought some derailleur extentions so threw one on. They work. I still have to figure out how to orient the extension.
Before and after (pardon the filth it’s a working bike)
bold stelvis
Kona Fan
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