Front derailleur reluctant to change up recently

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Brucey
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Re: Front derailleur reluctant to change up recently

Postby Brucey » 29 Jun 2020, 5:59pm

LittleGreyCat wrote:Difficult to work out how..


sometimes they just bend; this is common with stronglight 99/100 chainsets.

cheers
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Mick F
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Re: Front derailleur reluctant to change up recently

Postby Mick F » 29 Jun 2020, 8:18pm

LittleGreyCat wrote:New chain, 3rd time out, I think.
First lubrication after factory improved things briefly but then the problem returned part way through the ride.
That's the issue.

New chains in my experience, aren't very able to move sideways for a while.
They are stiff side-to-side and need breaking in to get more flexible.

Found this issue over the years on both bikes, but mainly my Moulton with a triple setup - 34/48/61 especially up to the 61t.
Mercian is 28/42/53 and still suffers with a new chain.
Mick F. Cornwall

bazzo
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Joined: 27 Jul 2012, 7:37am

Re: Front derailleur reluctant to change up recently

Postby bazzo » 29 Jun 2020, 10:57pm

Suggest you give everything a good clean and lube, then look online for how to set up front derailleur and follow it through. There is a Parktool one that is quite good.

Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Front derailleur reluctant to change up recently

Postby Brucey » 29 Jun 2020, 11:27pm

LittleGreyCat wrote:On the last couple of rides the FD has been reluctant to change up into the biggest ring.
3 * 9 transmission.


LittleGreyCat wrote:New chain, 3rd time out, I think.
First lubrication after factory improved things briefly but then the problem returned part way through the ride.


Needless to say if you have recently been changing parts, it is a good idea to mention that early on; it is almost certainly not unrelated.

If you could say what parts you have been replacing and more to the point what the old parts were as well as the new parts, perhaps some further light can be cast...?

cheers
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LittleGreyCat
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Re: Front derailleur reluctant to change up recently

Postby LittleGreyCat » 2 Jul 2020, 9:09pm

Brucey wrote:
LittleGreyCat wrote:On the last couple of rides the FD has been reluctant to change up into the biggest ring.
3 * 9 transmission.


LittleGreyCat wrote:New chain, 3rd time out, I think.
First lubrication after factory improved things briefly but then the problem returned part way through the ride.


Needless to say if you have recently been changing parts, it is a good idea to mention that early on; it is almost certainly not unrelated.

If you could say what parts you have been replacing and more to the point what the old parts were as well as the new parts, perhaps some further light can be cast...?

cheers


I am into the process of swapping between 3 chains (as recommended in various threads) to see if that can even out the wear instead of running one chain (and possibly some or all cogs) to destruction.

All that has been changed recently (apart from chains) is the smallest front ring.
28 changed for a 24.
This was discussed when I was trying to diagnose a strange clonk under load when climbing.
Potential conclusion was that it was a combination of pedalling style and a brand new chain adjusting to worn cog teeth.

As noted up thread, twiddling the stop screw has apparently cured the issue.
I did have to make a minor adjustment to slacken the cable slightly as it was grumbling about changing down to the smallest front ring.
However a couple of turns on the down tube adjuster and all is fine.

As soon as I get the chance I will give the drive train another check over as am still puzzled over the sudden manifestation of this problem some time after the last change made.
I can see that it might be a new chain with most of the initial stiffness still there but some of the factory lubrication worked out.
However I didn't see any sign with the other two new chains of the set of three.

It could be just a sign that the drive train is getting a bit worn and is less tolerant of new chains.

I am planing to take the bike into Spa for a service some time in the next month when in the Harrogate area so may well get a bit of the "Did you realise that....?". We shall see.

Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Front derailleur reluctant to change up recently

Postby Brucey » 2 Jul 2020, 9:56pm

one thing that might explain both the clonk and the bad shift might be if the RH BB cup has started to back out of the frame.

cheers
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LittleGreyCat
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Re: Front derailleur reluctant to change up recently

Postby LittleGreyCat » 5 Jul 2020, 8:15pm

Brucey wrote:one thing that might explain both the clonk and the bad shift might be if the RH BB cup has started to back out of the frame.

cheers


Thanks.

I will give that a check over next time that it is on the stand (probably a few days now).