What chain?

[mcb2080]

This is the front chain ring just to show any wear and tear

Another pic of front ring

This is the left hand side, the silver that you see is really just the imprints of the grips in the washer but there are defo loads of imprints probably from taking the wheel of so many times to try and fix the tension

Back left again

Right hand side, same again with the imprints

Sprocket to see what you think of wear and tear

 

[Gerry Attrick]

One thing, could the "chain slipping" possibly be the internal hub gears slipping? I admit, the sprocket teeth do not seem worn.

 

[mcb2080]

Gerry, the gears always seem fine, probably the only plus point.

Can a gear slip as there isn't a derailer or anything that makes the change move apart from going forward?

On closer inspection a couple of teeth on the front have been flattened at the top of the teeth, i.e no round on them at all and the sprocket has a slight angle of wear and tear to the outer part of it (if that makes sense)

Also I had done about 200 mile before I got a cycle computer so the mileage is closer to 1000 miles.

 

[Bigtwin]

One thing, could the "chain slipping" possibly be the internal hub gears slipping? I admit, the sprocket teeth do not seem worn.

I disagree. Follow the curve around and compare the gradient at the LHS to that one the RHS - I think there is a discernible difference to them - that's more than enough to get slip with a new chain. Bottom picture, hold a bendy ruler up to the screen.

Exaggerated example here:

 

[Gerry Attrick]

The teeth on the chainset are not cut regularly. This apparently assists in gear changing. (Though as an engineer I fail to see how!). So it is normal to have a few flat topped teeth.

If you are certain the hub is ok, then the only thing left is the chain. Get a new one. If the fault is still there, you can at least exclude the chain as the culprit.

 

[Gerry Attrick]

I disagree. Follow the curve around and compare the gradient at the LHS to that one the RHS - I think there is a discernible difference to them - that's more than enough to get slip with a new chain. Bottom picture, hold a bendy ruler up to the screen.

I also disagree BT. See my response above. Manufacturers deliberatlely cut (or press) the teeth in irregular shapes. I queried a chainset on one of my bikes for the same reason, using the phrase "cut by a first year metalwork student", only to be shown an identical brand new chainset. There appears nothing wrong with the chainset depicted.

 

[Bigtwin]

I also disagree BT. See my response above. Manufacturers deliberatlely cut (or press) the teeth in irregular shapes. I queried a chainset on one of my bikes for the same reason, using the phrase "cut by a first year metalwork student", only to be shown an identical brand new chainset. There appears nothing wrong with the chainset depicted.

I'm talking about the sprocket, not the chainset.

 

[mcb2080]

Cheers Gerry and Bigtwin for all your input.

I am going to take it back to the bike shop on friday and get them to check the chain ring and the sprocket again as well as getting them to check the wear on the frame where the washers go as I still think this may be the problem as I say that I have had a slipping chain almost from first owning the bike.

The only thing with the half link chain would have allowed me to push the wheel as close to the pedal side and I could have tightened the washers on to a fresh part of the frame that hasn't been tightened before hope this makes sense lol)

Cheers

 

[Gerry Attrick]

Sorry Bt, can't see where you mean. There seems no wear sufficient to cause chain slip to me.

Wear on sprockets tends to manifest itself in hooked teeth. I can see no evidence of that here.

 

[Bigtwin]

Sorry Bt, can't see where you mean. There seems no wear sufficient to cause chain slip to me.

Wear on sprockets tends to manifest itself in hooked teeth. I can see no evidence of that here.

The valleys appear to be unsymmetrical to me. Hard to tell for sure in a photo of course - need to insert a rod to check. But if they are as worn as they look to me, then that's as, if not more, worn than I've had them causing problems.

Just on deduction, if it's had 800 miles done on that one sprocket, I'd be rather surprised is a new chain didn't cause some problems.

 

[swee'pea99]

Forgive my ignorant input (I'm not being cute...compared to most hereabouts I know nuuuthing) but sometimes the right amount of ignorance can actually help...seems to me that if it's ok at first, and only goes pear-shaped after 50-60 miles, it must be something that's changed over the course of those miles. Which for me at least seems to rule out anything like wear, and suggests instead some kind of slippage somewhere in the system. When I built my fixie, I had a similar experience, which turned out to be simply the axle shifting very slightly in the dropouts over time. Since tightening the nuts with a 12" adjustable, the problem has completely gone away. Costs nothing to give it a try...?

 

[Rohloff_Brompton_Rider]

half link chain solved all my problems. they are more forgiving on tension, but it does make a weird noise, i like but some may not, same as hope hubs. i have a diamond back

 

[RedBike]

It sounds like your problems are because the back wheel is slipping/ moving in the dropouts. You can see where frames worn as this has happened.

If the wheel is moving then fitting a half link chain (or any new chain) isn't going to solve your problem.

I would use a new set of track nuts and ask about the posability of fitting chain tugs.

 

[RedBike]

Your chain should be tight enough so the chain doesn't sag but not so tight as it impedes rotation