Thorn Cycles Forum

Technical => Transmission => Topic started by: Matt2matt2002 on July 11, 2014, 08:22:50 PM

Title: chain problems
Post by: Matt2matt2002 on July 11, 2014, 08:22:50 PM
Hi folks. In the middle of my Scottish tour.
Last week the front chain ring expired. Stripped the cogs, so chain skipped rather than gripped the chain.

Local bike shop fixed me up with a new ring, slightly larger than my own. But it got me going again.
Had to adjust the bottom bracket but got it set with just the right amount of slack.

Just checked things out after 250 miles and I can see a gap between the chain and the ring at certain parts.
The chain appears to sit neat at the top but at 45 degrees and lower there is definatley a gap.

No skipping, noise,or clunks but I am concerned about the rest of my tour.
Could it fail suddenly?

Thoughts and advice gratefully sought.

Matt
Title: Re: chain problems
Post by: julk on July 11, 2014, 09:37:01 PM
Matt,
A worn chain will sag away from the chainring, how old is the chain?
julk
Title: Re: chain problems
Post by: geocycle on July 11, 2014, 09:40:20 PM
Hi Matt,
I'm an optimist so in answer to your question: you'll be fine!

Have you got any pictures? I'm still struggling to understand how you managed to strip the chainwheel. Is it a new chain?

You can usually get away with a very slack chain which only becomes a problem if it starts to fall off when you go over bumps. Even then just hook it back on and carry on.

Title: Re: chain problems
Post by: Matt2matt2002 on July 11, 2014, 09:50:11 PM
Very old but a good make KTM x1 ? ?
I ordered a new one before I left home!

Is what I am running now/the condition/situation, going to cause me any big problem for the rest of the tour?
800 miles loaded with x2 rear panniers and tent.
Title: Re: chain problems
Post by: JimK on July 11, 2014, 09:52:53 PM
Best to put a new chain on, but then you could have a problem with the sprocket in the back! A new chain might not work well with a worn sprocket!

Probably you will just wear that new chainring very quickly. Maybe just replace the lot when you get back home.
Title: Re: chain problems
Post by: Matt2matt2002 on July 11, 2014, 09:53:36 PM
Its not the slackness that is causing me concern. Its the fact that the chain links don't sit neat and tidy onto the spikes of the chain ring. Sorry no pictures can be loaded from this tablet.

Thanks for the optimistic opinion.

Any more thoughts folks?
Title: Re: chain problems
Post by: Matt2matt2002 on July 11, 2014, 09:56:43 PM
Best to put a new chain on, but then you could have a problem with the sprocket in the back! A new chain might not work well with a worn sprocket!

Probably you will just wear that new chainring very quickly. Maybe just replace the lot when you get back home.

I certainly will be replacing chain and both rings when back at the ranch!

I just don't like the idea of further problems on this tour.
Thanks for your thoughts
Matt
Title: Re: chain problems
Post by: geocycle on July 11, 2014, 10:01:37 PM
I think worse case scenario is you'll have to put up with a chattering noise if the chain and chainring are worn at different rates. Like Jim says, you could wear your new chainring a bit more quickly but you'll not wear it out.

But any bike shop should be able to put a new chain on. It will quickly object if it's not compatible.

Where are you now?
Title: Re: chain problems
Post by: Matt2matt2002 on July 12, 2014, 07:00:04 AM
I am stuck in Leverburgh Harris, waiting on a gap in the weather for a boat trip to St. Kilda.
Could be Sunday.
If not I'll push onwards to Skye. A boat leaves from Uig so I may have more luck there.
Matt
Title: Re: chain problems
Post by: geocycle on July 12, 2014, 07:56:51 AM
A great part of the world. Shame the weather sounds dodgy, or perhaps it's just sea conditions?

We have a few folk on the west coast who I'm sure will help you out when you get off the Hebrides if you need it!
Title: Re: chain problems
Post by: Matt2matt2002 on July 12, 2014, 08:04:21 AM
Many thanks. Yes, its the sea swell rather than rain, that's the problem.
Matt