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Discussion Starter · #1 ·
Fitting a chain (original Meriden, 3,000 miles use) to another hub.

The rear sprocket has some wear. It's possible the sprocket is original, wheel is flawless, just about.

Worth replacing sprocket? About £40 for a decent one.

Bicycle Wheel Tire Bicycle wheel rim Bicycles--Equipment and supplies
 

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Discussion Starter · #3 ·
Ok, thanks. Knew the test, thought that was for chain though.

If you think it's worn, that's good enough for me. To avoid any general misunderstanding, I'm saying your word's good enough, not the sprocket.

I have a running bike with thousands of miles on similar conical sprocket. No visible wear. So might indeed prise the wallet open...
 

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Discussion Starter · #5 ·
Thanks burger. I'll have to flip you 😃

It'd go one tooth less, not more. But not to be had with the conical. I've got a larger (19") rear wheel though.

Won't be buying a Yahaha though, I'll just buy the sprocket. More economical.
 

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Discussion Starter · #18 · (Edited)
I have a very small leak of gear oil at front sprocket. Just while riding. Works well. Never touch chain. Zero wear so far.
People silicone around the spindle to stop this leak ...

Another bike I'll soon have running doesn't leak here, unfortunately. 🤠

There's so many preferred methods. Was going to use gear oil (manually applied). I'll think about the Moto X grease.

I found this vid helpful

 

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Discussion Starter · #19 · (Edited)
A broken chain can kill you, fit the strongest link possible-this means riveted
I'm a bundle of nerves.

I reckon with no on-coming traffic or annoyingly placed street lamps, up to 40mph I'd survive oil starvation (conrod through crankcase), poor chain maintenance/quality/a clip link (whiplashed by chain), rapid inner tube deflation (head dive on tarmac).

Anyway, Peg, I'm working on reducing the odds. Is this a tool you was thinking of?
Auto part Font Metal Nozzle Cylinder


Costs less than £20, which isn't too bad.

Edit
Probably stupid question of the day. Can I rivet a clip-linked chain?

... I've seen this...
Automotive exterior Font Auto part Circle Automotive window part
 

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Discussion Starter · #22 ·
the key to reducing chain and sprocket wear is to buy another motorcycle, cutting the rate of wear by half on each one. better yet, own three motorcycles. your chain and sprocket life is tripled.
Three motorcycles here. None on the road. 😭
Indefinite chain life.
 

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Discussion Starter · #24 ·
Looking at your photo, something is or at sometime has been out of alignment.
The chain plates have been salami slicing the side of the sprocket. In an ideal world where the rear wheel (and sprockets) are exactly where they need to be, the painting on the sides of the sprocket would remain in pristine condition as only the rollers would make contact with the sprocket.
Thanks for the tip. It's one of a pair of bought wheels. Something I'll watch out for.
 

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Discussion Starter · #30 ·
Excellent.

You aren't doing it off the tyres, which some do, and bothers me. I'll give it a go when I've time.

How though do you measure off from the front wheel, keeping it properly aligned, not pointing slightly to one side?
 

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Discussion Starter · #32 ·
Hello Don

The engine, front sprocket and chain are all original and left factory together. They have only 3,000 miles use. The chain is Reynolds, and will presumably fit. I'll make a note of the 107t, thanks, for when I replace it.

The rear wheel is a replacement, so sprocket has more miles than them, almost certainly. So, thanks, I'll replace the rear sprocket. I've ordered a UK-made (LF Harris, I think) 47 teeth. Cost about £10 more than a sprocket with no given place of manufacture.

Thanks. I was thinking of using gear oil as lube, I'll do as you, then, that's settled! My other bike gets gear oil from a tiny leak at the primary socket. I know you won't approve! Works well though! I don't find the gear oil messy, just wipe from inside of rear guard and licence plate occasionally, and less occasionally from wheel rim.
 

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Discussion Starter · #34 ·
Don, the back sprocket is of unknown origin. Came on the replacement wheel I bought.
The engine, front sprocket and chain are all 3,300 miles of use and left Meriden together.

The engine, chain, front sprocket is 1979. I've opened the gearbox, looks good. Rest of engine never opened.

The rear sprocket is from a 1975 bike. It's off a Bonneville, but being 1975, it's a 19" wheel. The factory sit-in perhaps means the wheel was intended for a triple. We'll never know.

So, the back sprocket has more miles on in, judging by the wear.

I've not tried fitting the chain yet, I'll wait until new back sprocket arrives. Does it still sound 170t to you?
 

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Discussion Starter · #44 ·
If in doubt buy the BEST sprockets and chain and fit as a set. Oil the rear sprocket before each ride and honestly you won't need to touch that area for thousands of Ks . I am not exaggerating. On my 2006 Thruxton ,average riding 23000 ks and still no visible sign of wear .
3,000 miles on both (a set) original Reynolds chain and Meriden front sprocket is probably the best. Throwing them out makes no sense, in terms of quality replacement and effort in removing front sprocket (no small task), and is a waste of resources and money.
As you say, there's thousands of miles of life in them.
It's the on rear sprocket the question was raised; it is 'new' to me, came on the used wheel I have bought.
I'll throw the bath water out, not the baby.
 

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Discussion Starter · #46 ·
Apologies to Mr Renold for anglising his name.

Here's a picture of his chain. Just for interest, chain from Meridien factory. Not expecting any analysis of it condition.
I'll test its give around the new sprocket.

Automotive tire Tool Bicycle part Font Rim



split is just way easier.
Don't think anyone was claiming otherwise? A riveted-link was raised as being safer.

We on rare occasion had customer bikes that lost master link. I'd wager the clip was on backwards or not fully seated.
You'd not lose your wager! Impossible to know if clips were incorrectly fitted.
 

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Discussion Starter · #53 · (Edited)
As soon as sprocket wear is evident I replace both chain and sprocket, regardless of how old the chain is. I do this as I have found that even a slightly worn chain or sprocket accelerates wear on the other
I'll give it some thought. New chain isn't cheap, so it's a balancing act. 🤡
Edit
As stated, the rear sprocket is worn, but never used by me, came with wheel. So not necessarily a case for chain replacement.
 

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Discussion Starter · #54 ·
I'll check my chain for wear according to the Haynes Manual method. That is:

Lay lengthwise in a straight line.
Compress endwise so all slack is taken up.
Anchor one end, pull other end firmly.
Measure amount of stretch.
If exceeds 1/4" per 12 inches it needs replacing.


*

I just tested my chain/sprocke on running bike (i.e., not the cog/chain in this thread).
At 3 o'clock it lifts off a lot more than 1/16". However, the sprocket shows no sign of wear, teeth still symmetrical. I assume a worn chain would cause this lifting?
I ask because the pulling chain off sprocket is considered a sprocket wear test.
I know I can take chain off to do the 1/4" stretch test, I will. But useful to know what might be going on.

Thanks.
 

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Discussion Starter · #56 ·
Just tested my 1979 Renold 3,000 miles-use chain using the 1/4" per 12 inches stretch test.

Office ruler Rectangle Bicycle part Auto part Bumper


Flattened and scrunched together along a piece of steel, first. Measured. Pulled/stretching, measured.

Did it twice in different parts of chain. 1/16" stretch or less. So, I'm keeping the chain. It's low mileage and probably best quality. And came with front sprocket from new.

Paid a premium for a UK-made back sprocket that arrived yesterday. Not stamped with LF Harris, as it allegedly is!

*

Tomorrow, will test stretch on my running bike. Has an unknown number of miles usage. I've done about 2,500 on it.
Will make an interesting comparison.
Expecting to buy a new chain.
 
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