I'm running XT crankset, XT Shadow mech, Shimano HG74 10 spd chain, DT 370 SL rear hub. All with about 400 miles on the clock.
Problem.
Under load in the middle ring at the front and a high gear at the back, that is an almighty grating type noise, as soon as you put less power through it goes away and runs smoothly.
Also if you reverse pedal the chain jumps down the block.
The rear mech isnt bent (from what I can tell) the gears are set up correctly, the chain lubed correctly etc. The cassette wobbles very very slightly on the freehub body.
Causes?
All I can think is that either the freehub is knackered, or going? I've never had a DT hub before..
The only other thing that I did stupidly a few weeks back was that I put the chain on wrong! Poor description, but I looped the chain round the outside of the piece of metal above the final 's' of sjscycles in the pic below. I then did a 30 mile race with it like this. Afterwards when I realised, this piece of metal is now pretty worn out, and the chain was highly polished where it had been rubbing.
So is it worth changing the chain to see if this solves it?
Ta
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I would try a new chain. Did the same not long ago but fortunately I realised before I left the shed!
Bump..
New chain time.
Hmm I was thinking as much.
I wondered how much quicker I would have been in the race if I hadnt been turning all that friction!
is chain line ok ? chain jumping down block when reverse pedalling can often be a combination of worn drivetrain (and it sound like your chain is a bit gubbed)and the line being a bit wrong
I will check the chain line, but unlikely to be wrong as its newish factory bike (Anthem X) and not had any changes made to it, plus the fact it has worked faultlessley before.
Think its going to be new chain time..
Check how free the jockey wheels and free hub are turning.
How old is the chain? Stiff links?
The bike was bought brand new 9 months ago, but has only been used for the last 3 months as I had serious illness which kept me off the bike.
The chain has been off and cleaned properly, as no stiff links etc. I think I will the freehub/jockey wheels etc and good once over and if nothing jumps out there, get a new chain.
Maybe refer my learned colleague to the thread concerning 2 y/o cleaning bike and other minor maintenance issues...
sounds like the rear derailleur could be bent a bit, or the mech hanger
may be chain line, could be that the jockey wheel is too close to the large sprocket. Adjust the B tension screw to move the angle of dangle, as it were.
I'd just drop it in to your LBS and ask them to do whatever they think is required.
Wouldn't have thought it would cost much...
All sorted now.
Spent an evening fettling outside in the sun with a beer or 2 and no disturbance from Jnr FD!
Turns out 2 things were wrong. Firstly, on a previous ride I had noticed that I had again put the chain on wrong whilst out riding so took the lowest jockey wheel out to run the chain correctly. I had over tightened the jockey wheel when I put it back in so the chain was rubbing on sides of the cage.
I had also at some point taken the rear gear cable off to clean it all out. I had then put too tension back in the cable when putting it all back together. The gear change is now actually punchier again.
All this is school boy error stuff, that comes about from rushing doings jobs, as having a 2 year old around when your doing it doesnt always help!