mtb/ road shimano gearing help needed
hello i have a dawes galaxy that came with rsx mechs and chainset and bar end shifters, i've heard that the mtb mechs need different pull to the road ones, which do i have? i have it set up with some 105 sti's that i was given and the indexing is as you can imagine hit and miss, is there anything i can do to improve it in the short term while i save for the bits for 9spd (is currently 7spd) was going to go for a stronglight impact chainset with lx hubs and 105 or tiagra 9spd mechs (whatever i can get for a fair price) ideally with a 11-32 mtb cassette, am i going to have problems? the road mechs seem to only go up to a max 27t for the cassette,
any help would be appreciated
Ta
Cf
any help would be appreciated
Ta
Cf
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Comments
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"i have it set up with some 105 sti's that i was given and the indexing is as you can imagine hit and miss, is there anything i can do to improve it in the short term while i save for the bits for 9spd (is currently 7spd)"
WHICH bits are currently 7 and which 9? Clearly only 7 speed sti will work witha 7 speed cassette/block! But 9 spd shifters should I think work with an rsx mech - the mech doesn'y know how many times it is pulled!
As you say, road mechs only reach to 27 - in theory at least. Which is why tourers often run mtb rear mechs. Have a look at e.g. sjs cycles Thorn specs to get an idea of what you can mix. Can't see why 105 shifters shouldn't be o.k. with e.g. an LX rear and an mtb cassette.
Thoughts only!
d.j.
"Not much to see,
Not much left to lose"0 -
hello the only 9spd bits are the sti's the rest is 7spd (1997 ish i think. i was led to believe that the mtb shifters pull different amounts of cable to the road ones so the indexing would not work properly
Cf0 -
It's MTB front mechs that have a different cable pull - all shimano rear mechs have the same pull. I think the issues you're getting are to do with having 9 speed STIs on a 7 speed cassette. A possible fix for this (check out Sheldon Brown for confirmation) is to get a 9 speed cassette, take it apart and remove 1 cog and spacer. This now 8 speed cassette will fit on a 7 speed bub and work with 9 speed STIs. Keep the cog and spacer safe for when you've got your 9 speed wheels etc.
Hope this helps.0 -
ahh thanks for that will search out a 9spd casette (sure i have one lying around somewhere), thanks for that
Cf0 -
The fact that the "indexing would not work properly" is because of 7 v 9, not road v mtb (which is a different subject!).
d.j.
"Not much to see,
Not much left to lose"0 -
thanks i knew that the problem was 9 vs 7 but was wondering if there was a bodge fix to improve matters or a little widgety thing that would alter the pull (like a shiftmate or something) ,
cf0 -
Hey CF!
The front mechs have a different pull. Rear is all good. From what I hear, the best front mech that works with road shifters and touring chainsets is the IRD Alpina. If you can't get hold of one, I'll post one to you
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