Chain is climbing the sprockets

[Kell]

Anyone else running the new sprockets yet?

After having a wheel rebuilt I ended up with the new style sprockets on the rear. As I had new sprockets I also fitted a new chain.

But it's been a bit patchy. the chain keeps jumping on the sprockets - as if fitting an old chain to new cogs. Both are the correct Brompton spec, so I'm puzzled as what might be causing it.

It's not all the time, and at the minute it's not often enough to know which gear I'm in when it happens. On an 8 mile ride this morning it happened maybe three times - once under load while going up hill, and at least one other time while I was seated and just pedalling along as normal.

Just intrigued to know if anyone's experienced similar and what a likely cause might be. If I didn't know (or assume) better, I'd say the new style cogs have a slightly different profile to the old.

Also fitted a new chain pusher, a new dogleg and a new chain tensioner, but it was doing it before and after fitting those, so convinced they're not part of the problem.

 

[rafiki]

I guess you have checked the chain for a stiff link?

 

[Kell]

Interesting. Completely forgot that as a possibility. Chain, sprockets and chainring came off this weekend for a full clean - no stiff links that I could see or feel.

Although in fairness, at that point I wasn't specifically checking for one.

It's possible I missed one.

I'll have a look this evening and report back. I suspect not, as it was doing this at the outset when it was brand new (and on my old chain when I first fitted the new sprockets) - which at that point I put down to chain stretch.

 

[rafiki]

Yes, worth a check but if the old chain was doing the sane then unlikely, as you say.

 

[I like Skol]

Is the indexing correct? Wheel rebuild could have moved the sprocket alignment.

 

[12boy]

Ah, the scourge of mystery problems that occur erratically. Hate that.
I took my bike to Albuquerque NM, 800 miles south to spend some time with family there and bought some tire liners yclept "RhinoDillo" as the goat head problem there is a pain. Goat heads are nature's own caltrops, see the pic. The thorns are about 1/4". Of course, I did not pick up any, which would have gone right through my Marathon Racers, but the liners really made riding hard work and stodgy. I do ride for exercise but feeling like I am dragging an anvil does suck the joy right out.

 

[Kell]

Checked the chain and there are no stiff links.

I’ve ordered another spacer to see if that helps. The yellow one looks very wide.

 

[Sharky]

new style sprockets

Must have been asleep, what are these?
Any chance of a link to them or a photo?

Thanks

 

[Kell]

https://brilliantbikes.co.uk/brompton-rear-sprockets-and-spacers/357-brompton-bwr6-stack.html

 

[ExBrit]

I just installed these sprockets last night with a new bling gold chain. I'm thinking a test ride is in order before I ride my 50 mile route Sunday. Thanks for the heads up

 

[ukoldschool]

I had the same issue you describe yesterday, but mine was a leaf caught up in the rear

 

[Kell]

My new spacer has arrived. Will fit a the weekend and go for a test ride.

It is weird. I've not HAD to do too much to the bike since I got it, but all of a sudden loads is going wrong at once.

 

[Fastpedaller]

The new sprockets - I guess they are standard Shimano sprockets as used on 8 speed cassettes? I have a 2007 superlight which had zero miles when I became its new owner last year. After a ride I decided on closer ratios, so replaced the smaller sprocket with a 14T. I noticed the 13 T removed had 'squarer' profiles ie more like a traditional freewheel sprocket, and slightly higher teeth. Reckoning that as the Shimano sprockets work ok on my road bike I thought there would be no problem, and there wasn't. Now to yours.... Is the new chain the same width as the old? Is it definitely the chain jumping, and not the Sturmey slipping ? as the adjustment on the toggle could have been moved when the wheel was removed/replaced. As you said the spacer may be suspect! Apart from those thoughts, I'm stumped.
ETA - mine in only 2 speed.