Falconista

I am getting occasional chain drop on the front cog of my Moulton TSR and was looking for advice/ideas on a fix.

It was a standard TSR 9 which I upgraded to Shimano XT 11 speed (on inspiration from Pinholecam from this forum). However I left the front chainring as stock (Sturmey Archer 54T with double chain guard and generally it all works well.

However occasionally (maybe every four or five rides) when changing up a gear and near top gear the chain jumps off the front ring and jams between the chainring and outer chain guard.

I suppose that this is because the 11 speed chain is slightly narrower than the original 9 speed. The clutch on the XT derailleur is set in the right position and chain tension is OK. It has always done it so not the age of the chain.

1) Should I just use some force to squeeze/bend the chain guards slightly narrower? I can see that might cause a real jam if it came off again.
2) Swap the chainring to one with narrow wide teeth? Litespeed seem to make one with 54T although it doesn't always specify for 11 speed. Would it work with the existing guards to keep oil off trousers etc?
3) Other options?

Thanks in advance for the input. Apols that I can't post pictures in my first post.

PS I have got a load of help on bike works from searching this forum in the past. It has been much appreciated.

Jipe

This front chainring is not a 11s compatible chainring, I guess that's the reason especially if it happens with the smallest cogs where the chain is less tensionned by the rear derailleur.

Falconista

Thanks Jipe. I understood the inside of all chains are the same diameter, so a single chain ring will handle all chains. In this case it works fine except the occasional jump off, probably due to the chain line or as you say less tension.

Curious if anyone has successfully used the litespeed narrow wide option which seems attractive. Squeezing the chain guards is cheaper but doesn't allow me to order new bits and look forward to receiving them in the post...

zebede

This happens on my 1x8 Tikit. I am using a short cage derailleur and a bio-pace chain ring. I have theorized, during a shift, that when the derailleur arm snaps forward on an to smaller rear cog, at relative high cadence, it can send a "wave" of loose chain forward, aggravated by my biopace (ovalish) . Since a 1x system has greater chain angle than 2x it is more prone to the chain coming off the front ring, to the outside. As with you, it is an occasional phenomena.

Solutions: I have removed my outer chain guard so there is no jamming (it just comes off), My primary solution has been to just slow down my cadence more than usual and shift slowly, on the upper end.
I cannot fit a conventional chain keeper or chain guide, as would be my preference.
The only idea I have for you: If there is such as thing as a 5 bolt chain guard with an off-set inward to narrow the distance. Alternatively reduce the distance by riveting a ring on the inboard side of the chain guard.

Vanrex

I'm not familiar with the Litespeed chainring, but I've been using a narrow wide Wolf Tooth 52T in my 1x10 setup for a couple years now. I haven't dropped a chain since I installed it, whereas before the chain would drop off the outside every few rides (even with a clutched rear derailleur), with the problem getting progressively worse as the chain wore.

pinholecam

LitePro has a 10sp narrow wide chainring option.
https://www.lazada.sg/products/litep...TdbLP&search=1

This is a local online shopping site, but I think you should be able to find a similar one via Amazon, Ebay, AliExpress, etc.


I did not get chaindrops from my TSR setup, though I did more so with another 1x setup on a mini-velo (with Sora).
For the latter, I added a dis-used FD w/o any cable and it solved the problem.

Falconista

Thanks all. It seems that the narrow wide option is best. I meant LitePro (not Litespeed which I used in the first post) as the (only?) option for a 54T narrow wide chainring with 130BCD. They are available on ebay for not a huge amount,

Now I just need to decide whether to get the whole LitePro crankset (which looks quite good and also light), or just the chain ring and keep the SA crank and outer guards. Decisions decisions...

2bridges1bike

This has been my experience as well. I would also add that a chain guide can help reduce, but not eliminate, the waves mentioned above. Search for “chain guide” On the page below.

edit: See also the Tern Mainstay also on the page below.


Special Parts Dahon Tern and others

dukeiii

Sram force CX1 is another narrow-wide chainring option. It comes in both 110 and 130 standards with different teeth # options.

Falconista

Thanks all for the comments and help. I bought a cheapish narrow wide chainring from ebay. I think it is by Litepro but not absolutely certain.

It took a while to fit, and I had to abandon the outer guides from the initial installation as the original Sturmey Archer chainring is actually slightly dished, but the new one is straight, and was too close to one side. This needed 5 shorter bolts, but luckily I had some in the parts box. I also had to sandpaper the holes to get the bolts through on some.

Only after reassembling everything did I realise that the chainring didn't fit in the chain! The advert said 9-11 speed compatible, but I guess it is not...

I ended up going back to square one. I will look at the Wolf Tooth option but will be more expensive.

Fentuz

This litepro is to thick.

have a look at these. That what I put on the jetstream
https://www.sjscycles.co.uk/chainrin...ainring-black/

Jipe

SJS says 9-10 speed, not compatible 11s !

Fentuz

my bad, i did not read properly

then https://www.chainreactioncycles.com/.../rp-prod197716

out of interest, what are the dimension of a 11 chain vs 10,9.

I measured 9 at ~6.25Mm and 7 at ~7mm

Falconista

The TA Alize option is 9/10 speed, and I don't think is narrow wide.

Wolf Tooth unfortunately only goes up to 52t and I am looking for 54t as a direct replacement.

The SRAM option is expensive but looks quality. The aero look is a little in contrast to the spaceframe but interesting.

Even more expensive is the specialist route. Found these two. Slightly concerned about pretending to be a time triallist when I just wanted the chain to stay on but the carbon fibre chainring might be amusing on a steel bike.
https://www.fibre-lyte.co.uk/fl/fl_c...ring_2011.html
https://www.pyramidcycledesign.co.uk...236/category=0

Of course the chain guide option is still there. I could also add an old front mech without cabling from the parts box.

Falconista

I believe that 11 speed is 5.62mm, and 10 speed is 5.88mm. Some commentators say that 10 & 11 speeds are close enough to be interchangeable, but in this case it wasn't close.

I did note that the chain fitted ok on one part of the chainring. As I had also problems fitting the bolts, I wonder if it was just out of spec, or wasn't a genuine product. I did buy if off ebay...

zebede

Go here Do this.