Cycling pros and gods I need your help

ColinJ

It's a puzzle ...
If your riding is flat or you’re fit, maybe you could convert to single speed?
It'll have vertical dropouts, so single-speed would be problematic.
I still think it can be possible?
Oh yes. You'd need a combination of chainring/rear sprocket sized to give a reasonably taut chain, or a chain-tensioner. Neither of these would be suitable for fixed-wheel. Or an eccentric rear hub (made by White Industries, I think) to allow tensioning.
I built a singlespeed bike with a (much older) Specialized Allez frame given to me by a friend. I chose a 52/19 ring/sprocket combination to get a good gear ratio for flat/undulating roads, but it is ok for longish climbs at 4-5% or even short ones of 8-10%. I did a 3 km climb including 0.5 km at 8% on it yesterday on a 161 km (imperial century) ride and it was fine. I have ridden thousands of kms on the bike and that experience tells me that it would be ideal for commuting anywhere where steep hills are not involved.

I fitted a Planet X 'Doofer' chain tensioner, available for less than £10. I used it as designed for a few rides but found on rough local roads that the tension arm bounced and the chain was coming off so I modified it to work without a spring*** and manually adjust it as the chain loosens with use.

Singlespeed Specialized Allez.jpg


*** I removed the spring, then added a large washer so the attaching bolt would tighten the arm up against the dropout to stop it moving. I also reversed the direction that the tension is applied, reasoning that the tensioner would be helping to wrap a loose chain round the sprocket rather than trying to peel it off! That has been the case, but the tensioner is a bit noisy in operation. I might try applying the tension in the other direction to see if it is still reliable, but quieter.

The chainline and alignment of the pulley wheel on the tensioner are critical. If they are right then the chain stays on and runs smoothly. If not, it will probably run rough for a few minutes and then fall off!
 

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Dogtrousers

Kilometre nibbler
As above, need to know which bits are screwed and which aren't.

I'd go for a clean up & lubricate, maybe replace the brake blocks, then ride it a bit and see what works and what doesn't. If the shifting works, or sort-of works, then it can probably be fixed with some or all of cleaning and lubricating, new cables, adjustment, a new hanger.
 

palinurus

Legendary Member
Location
Watford
Groupset? nah, usually at most cassette and chain might be worn. I've hardly ever had to replace shifters, mechs due to normal wear. Cables and outers sometimes. Looks tidy enough- what is it that doesn't work?
 
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Nb1

Nb1

Regular
OK guys here are the pics the main issue is it can change gears while stationary but can't change cogs on the front derailleur, as soon as you try and ride it and change gears it throws the chain or just gets jammed up, loads of noise and jumping about from the back derailleur and that hanger doesn't look like it's the correct part not sure how much affect that will have
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CarlP

La-Dee-Rhum-Buckedee-Ni-Ni-Nooo
A photo the right way up might help.

spesh.png
 

nickAKA

Senior Member
Location
Manchester
Stage 1 - Clean all that gunk off everything. I wouldn't generally suggest attacking it with degreaser but I think that ship's sailed. Go at it with a toothbrush & rags and some decent degreaser, it looks like tar!
Once properly clean get some chain lube on it.
Stage 2, it could be the angle of the picture but the alignment of the rear mech looks terrible. Every liklihood it is the hanger, thoughts everyone?
 

Vantage

The dogs chew toy
Stage 2, it could be the angle of the picture but the alignment of the rear mech looks terrible. Every liklihood it is the hanger, thoughts everyone?
The hanger itself looks straight enough but the bolt which connects the mech to the hanger looks bent or the bushes are worn to death. Of course it could also have been fitted cross threaded...which I think would be difficult given the size of those bolts.
 

I like Skol

Hold my beer and watch this....
X2 I also think the banger looks straight, but either that rear mech cage is mangled or, as Vantage says, the mech bushes are more worn than anything I have ever seen before. The jockey wheels are almost bald and the cassette teeth are not far behind.
As a minimum you will want a new rear mech, cassette and chain. Maybe some chainrings at the front too?

That might be all you need, the rest usually doesn't wear as soon.
 
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