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Rear Derailleur Query
My son's bike (Carrera TdF Junior) has Shimano Tourney 7 speed groupset but we are finding that the rear derailleur is going out of adjustment regularly. Last time it lasted about 10 miles before it started getting noisy and missing changes (again). I've checked everything I can think of so I am considering replacing the derailleur with a spare Tiagra 10 speed one. Are there any compatability issues I should be aware of?
Thanks.
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8 comments
Have reset the cable. Unclamped at derailleur and made sure shifter was clicked to highest gear. Pulled cable through, reclamped and reset the gears. Thrashed it up and down the road a bit (5ft 10 bloke on a road bike for a 9 - 10 year old
) and did some aggressive changes. All seems good but if it goes again I'll get a new inner fitted.
Thanks all - much appreciated.
Sounds to me like the cable slipping (e.g. at the rear derailleur) or getting frayed and worn through. Like cqexbesd, I had a similar problem and in the end, the cable snapped in the shifter (I had to tie up the cable to shift it to a sensible gear to get home).
I wouldn't think that a 10-speed would be compatible with 7-speed, but have never tried it so I don't know for sure.
I had something vaguely similar. We were on tour and I had to keep adjusting the barrel adjuster. By the last evening I was in despair as nothing I did could keep it aligned for more than 10 minutes. On the morning of the last day the cable just snapped and I had no rear gears at all.
In hindsight the problem was obvious and I should have worked out what was happening days earlier but there was nothing visibile - the break happened inside the housing.
Maybe its worth pulling out the cable and/or replacing it on spec.
Hi Podc,
It sounds like something is slipping somewhere in the cable run. Are you having to continually adjust the barrel adjuster in one direction?
I had an issue with a front derailleur that sounds superficially very similar - I kept having to adjust this thing, even after quite short periods (and always in the same direction). In the end, it turned out that the converter that allowed my top-pull frame to use a bottom pull front derailleur - a pulley clamped to the down tube - wasn't secure enough, and so was gradually sliding up and shortening the total cable run length. I realise your problem won't be related, but the lesson it taught me was to consider the whole cable run, not just the shifter/derailleur...
Cheers - I'll have another look tonight
Bit odd - Tourney is reliable and widely used on touring bikes. Remember the gear cable should be slighty slack (without any tension) when on the smallest cog (the derailleur should be resting on the limit screw). The indexing should be set so that it seems perfect in the middle of the cassette.
The bike has probably only done aboout 200 miles from new and I have inspected everything I can get at!
When set up, it is smooth, quiet and changes gear precisely and quickly right through the cassette. After a few miles (last ride it started at about 10 miles after adjustment) the gears start to become noisy and if not attended to, eventually starts skipping. A twist or two of the barrel adjuster at the RD end gets it back shifting smoothly again.
I haven't had the inner cable out properly but it feels fine when the inner is given a tug - returns without any hint of sticking. I'll try stripping it out and giving it a clean.
stick with the tourney.... and if it's going out very quickly.... cables okay? bent mech?... and how is it going out of adjustment....gear selection? or....... usually Tourney is relatively bulletproof