Author Topic: sprocket flipped at 7000 miles  (Read 2391 times)

hendrich

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sprocket flipped at 7000 miles
« on: April 21, 2021, 01:43:55 pm »
The drive train was noisy on our tandem so I flipped the sprocket and the noise vanished. The wear in the sprocket was subtle, difficult to see. The spline carrier made it a very simple task. 7000 miles, I presume I can expect another 7,000.

PH

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Re: sprocket flipped at 7000 miles
« Reply #1 on: April 21, 2021, 01:59:59 pm »
Without changing the chain?
No, it’s swings and roundabouts as to which would offer best value, but the chain will have worn at the same rate as the sprocket.  So although it seems to be running fine, the wear on the fresh teeth will be accelerated.  How long it’ll last is a complete guess. I’ll go half

Matt2matt2002

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Re: sprocket flipped at 7000 miles
« Reply #2 on: April 21, 2021, 10:57:58 pm »
Good topic and interesting figures.
I'll check my own soon.

Anyone else with milage figures for rear sprocket?
I appreciate the numerous variables with chain/ Chainglider etc.

Best
Matt
Never drink and drive. You may hit a bump  and spill your drink

hendrich

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Re: sprocket flipped at 7000 miles
« Reply #3 on: April 21, 2021, 11:24:08 pm »
The chain was replaced shortly before flipping the sprocket, it was the 2nd chain...i.e. 2 rear chains in 7000 miles. The drive train noise persisted after a new chain. I flipped the sprocket and the noise vanished.

John Saxby

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Re: sprocket flipped at 7000 miles
« Reply #4 on: April 21, 2021, 11:26:49 pm »
Quote
7000 miles, I presume I can expect another 7,000.

Mmmm, maybe not, Michael.  I flipped the sprocket on my Raven at a little over 10,000 kms, and replaced it at nearly 17,000.  Maybe it could've done another season, but I changed it anyway.

Cheers,  John

 

PH

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Re: sprocket flipped at 7000 miles
« Reply #5 on: April 21, 2021, 11:36:43 pm »
The chain was replaced shortly before flipping the sprocket, it was the 2nd chain...i.e. 2 rear chains in 7000 miles. The drive train noise persisted after a new chain. I flipped the sprocket and the noise vanished.
In that case I don't see why one side of the sprocket shouldn't last as long as the other.
I don't know about tandems,  I assume they wear components faster, on a solo I'd have been very disappointed at two chains in 7,000 miles.

hendrich

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Re: sprocket flipped at 7000 miles
« Reply #6 on: April 22, 2021, 03:45:03 am »
In that case I don't see why one side of the sprocket shouldn't last as long as the other.
I don't know about tandems,  I assume they wear components faster, on a solo I'd have been very disappointed at two chains in 7,000 miles.
Yes, we typically go through a rear chain at approximately twice the rate of single bikes. On a derailleur bike I would have changed the cassette with the chain, so twice over those 7000 miles. So, 1 sprocket has approximately the same lifetime as 4 cassettes. The timing chain lasts twice as long as the rear chain. No chaingliders for tandems.

Thanks John, good to have some comparable numbers on longevity. We long for Gaspe again, but we will need to wait a year.
« Last Edit: April 22, 2021, 03:51:54 am by hendrich »

steve216c

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Re: sprocket flipped at 7000 miles
« Reply #7 on: April 22, 2021, 09:41:42 am »
Good topic and interesting figures.
I'll check my own soon.

Anyone else with milage figures for rear sprocket?
I appreciate the numerous variables with chain/ Chainglider etc.

Best
Matt

Not for tandem, but I flipped my rear sprocket when I bought my bike 2nd hand, and I am almost 9000km on a Connex 808 chaing using the flip side already. Chainglider added at arond 5000km of those 9000km.

I suspect sprocket wear is less when protected from the elements than when exposed. Less wear if you keep the added friction of dirt and grime at bay.

I'll be changing out later this year for a splined carrier and new chain sprocket, so can try to keep book on longevity with chainglider protection from the offset once I've installed. Just trying to push my current chain and current sprocket to 10,000km if I can before then.

If only my bike shed were bigger on the inside...

mickeg

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Re: sprocket flipped at 7000 miles
« Reply #8 on: April 22, 2021, 02:46:00 pm »
The chain was replaced shortly before flipping the sprocket, .... I flipped the sprocket and the noise vanished.

Last year I put on a different chain on my Rohloff bike, not new but it was much less worn.  Had noise and I had an odd feeling in the pedals, like the chain was catching on each link.  And that odd feeling was stronger the harder I pedaled.

Flipped sprocket to a new side and everything was fine.

The teeth wear to the shape of the chain links, elongated links on a worn chain will wear the teeth differently than a new chain with non-elongated links.   So, I suppose this should have been expected.

That is why some people on derailleur bikes will frequently change two or three chains on a bike in a planned rotation, in the hopes that they can wear out two or three chains for each cassette.