Chain Slipping

[Boneshaker]

I'm riding my Peugeot Premiere racing bike, around 25 years old.

The chain started slipping, so I measured it and found that it was a bit stretched. I replaced it with a new chain from Halfords, sort of a silver type supposed to be rust proof. All this was around 2-300 miles ago.

The chain still slips now and again (getting worse) when I'm in highest gear (small cog).

I've checked the chain and can't find any stiff links.

Could be that the cog is worn, although it doesn't look that bad.

Any ideas please?

 

[GilesM]

I would say that the rear sprockets (cogs) are worn, I'd suggest replacing them aswell.

 

[Rhythm Thief]

Usually you need to replace the rear cogs at the same time as you replace the chain, as they wear together. It might be a bit tricky to find a new rear block for a bike of that age.

 

[Alf]

Sounds like it. If you wear the chain so much that it starts slipping, you are bound to have worn the sprockets out as well (maybe the chainwheel too). It is not always easy to see the wear but the teeth will probably be a bit hooked.

Unfortunately, you may have to replace the chain again too since using a new chain with worn sprockets wears the chain out very fast. The only way to check is to measure the chain. You can do this either with a chain measuring tool (set you back about a tenner) or you can take the chain off, hang it on a nail and measure 50 inches. If the 100th link comes a full link down from the 50 inch mark, it is 1 percent worn and needs replacing. A lot of people (including me) change the chain at the 0.75% mark to avoid having to replace the cassette every time.

Alf

 

[Boneshaker]

Thanks Fellas,

I didn't realise that I should have replaced both atthe same time.

If I have to get a new wheel because I can't get a rear block then so be it. Dissapointing though as I like the fact that everything is original. Ah well.

Thanks again guys.

 

[swee'pea99]

Usually you need to replace the rear cogs at the same time as you replace the chain, as they wear together. It might be a bit tricky to find a new rear block for a bike of that age.

No it won't! Easy peasy lemon squeezy. Ebay has loads - you can take your pick. Just make sure you get a freewheel, not a cassette. This looks a good'un. Or you can go cheap as chips. Or something like this, for a tenner.

(Oh, and I wouldn't worry too much about your chain. 200-300 miles? It'll be fine.)

 

[Alf]

I wouldn't be too pessimistic about the block. You can still get 5-speed freewheels quite easily (here for example: http://www.spacycles.co.uk/products.php?plid=m2b0s112p0 ). You will need a freewheel tool to get the old one off, though, and there are several different types. Bike shop would do that for you (in about 30 seconds) if you didn't want to bother yourself.

Alf

 

[tyred]

You should have no problem getting a 5 or 6 speed block. Halfords stock them, as do any number of online people. Type "freewheel" into ebay. The one for my Pug cost 99p from ebay. If you strike it lucky on ebay, you may even get a NOS like for like replacement with your current block to preserve originality.

 

[swee'pea99]

Oh, PS, you'll also need a freewheel remover (you can get those off ebay too - but you'l need to know what make your freewheel is, 'cos the fit isn't universal), and be prepared for a battle...they can be a bugger to remove, especially after they've been on a few years. It is doable tho' - I usually end up resorting to a great big adjustable and a few sharp whacks with a hammer. Oh, and grease up the threads of the new one before you put it on - that'll reduce the grief *next* time you need to get it off. Good luck!

 

[tyred]

Removing the old one could be your biggest challenge as old freewheels are always tight and didn't always have splines like more modern types. Patience and a hammer and chisel are your friend.

 

[Boneshaker]

Thanks swee'pea99.

Placed bid, job done.

Really appreciate the help.

 

[swee'pea99]

Excellent - hope it goes well. Come back if it all goes pear-shaped!

 

[Boneshaker]

Right then,

I've got the new sprocket, now the fun begins.

Quick question, what tools do I need?

I'm told by "some bloke" in the pub that I need a chain whip remover, and a freewheel remover.

Is this right?

 

[Hacienda71]

Sounds about right. The chain whip allows you to stop the freewheel from spinning by wrapping a chain with a handle around the freewheel cogs giving you leverage, while you use the cassette remover to undoe the retaining thingy/nut in the middle of the freewheel.

 

[Boneshaker]

Thanks Hacienda.

More ordering on Ebay.