Chain slipping Between Chainrings

For discussions about bikes and equipment.
iandusud
Posts: 1577
Joined: 26 Mar 2018, 1:35pm

Re: Chain slipping Between Chainrings

Post by iandusud »

slowster wrote: 23 Jun 2022, 6:42pm
roubaixtuesday wrote: 23 Jun 2022, 3:47pm
slowster wrote: 23 Jun 2022, 2:24pm I would definitely give Spa a call. It might be that although the chainsets as sold are suitable for a wide range of different speeds as advertised on the website, their mechanics may have experience and knowledge of how to fine tune them to make them work better for particular configurations or in the event of a more demanding set up, such as on a tandem.
Whilst the consequence of this might be more severe on a tandem, I don't at all understand why it being a tandem is "more demanding" from the POV of the basic function of a chainsaw? It's identical surely?
I am supposing that the derailleur cage may need to move with a minimum speed for a clean downshiftshift, and that too slow a movement of the cage might cause the problem that the OP is experiencing, which might in turn be caused by more friction in the cable run on a tandem.
The derailleur is moving very sharply - no excessive friction in the cable. I'll give it a run at the weekend and see how it now performing.
User avatar
Mick F
Spambuster
Posts: 56359
Joined: 7 Jan 2007, 11:24am
Location: Tamar Valley, Cornwall

Re: Chain slipping Between Chainrings

Post by Mick F »

iandusud wrote: 23 Jun 2022, 3:59pm
Mick F wrote: 23 Jun 2022, 3:19pm Either use a wider chain, or grind down the spacers.
Been there, done that.
Nowt to do with indexing.
I assume that a wider chain (9 speed) wouldn't work with a 10 speed cassette.
Of course not.
My issue was swapping a 10sp Connex chain for a 10sp Campag one.
Indexing was, and still is perfect but the Campag chain, being narrower, would often sit between the outer and middle rings, and the cranks would spin.

Grind down the spaces a tad, and all is, and has been, sweetness and light.

Not tried a Connex chain since, but I have no doubt that it would be fine.

http://www.stronglight.com/stronglight/ ... uit?id=276
Notice that it says that it's 9sp and 10sp compatible. No mention of how wide (or narrow) the chain can be.
Mick F. Cornwall
roubaixtuesday
Posts: 5815
Joined: 18 Aug 2015, 7:05pm

Re: Chain slipping Between Chainrings

Post by roubaixtuesday »

Jdsk wrote: 23 Jun 2022, 5:15pm
roubaixtuesday wrote: 23 Jun 2022, 3:47pmWhilst the consequence of this might be more severe on a tandem, I don't at all understand why it being a tandem is "more demanding" from the POV of the basic function of a chainsaw? It's identical surely?
That's a serious multitool!

: - )

Shirley
Lol. I'm an idiot who should check his posts for autocorrect.

But a bicycle powered chainsaw? Hmmmm...
User avatar
Cugel
Posts: 5430
Joined: 13 Nov 2017, 11:14am

Re: Chain slipping Between Chainrings

Post by Cugel »

roubaixtuesday wrote: 23 Jun 2022, 8:34pm
But a bicycle powered chainsaw? Hmmmm...
I've often wondered if a fine fit cyclist could power my table saw. This would save on lecky .... but the bill for the cyclist grub might far exceed such a saving. I suppose I could set a trap by the front gate, get one on to the tablesaw bike, then "excite" the fellow (or even a strong lady) until they had given me their all. At that point I release them and they grovel off on the rivet, just grateful to escape even though I didn't give them so much as a piece of cake.

Then, if the plank is still needing a cut or two, I fish another one out of the trap ......

Cugel, having illicit fantasies.
“Practical men who believe themselves to be quite exempt from any intellectual influence are usually the slaves of some defunct economist”.
John Maynard Keynes
Jdsk
Posts: 24640
Joined: 5 Mar 2019, 5:42pm

Re: Chain slipping Between Chainrings

Post by Jdsk »

Cugel wrote: 23 Jun 2022, 9:59pm
roubaixtuesday wrote: 23 Jun 2022, 8:34pm But a bicycle powered chainsaw? Hmmmm...
I've often wondered if a fine fit cyclist could power my table saw.


Jonathan

PS: And, of course, a chainsaw will power a bicycle.
roubaixtuesday
Posts: 5815
Joined: 18 Aug 2015, 7:05pm

Re: Chain slipping Between Chainrings

Post by roubaixtuesday »

Cugel wrote: 23 Jun 2022, 9:59pm
But a bicycle powered chainsaw? Hmmmm...

"excite"... ...a strong lady)

Cugel, having illicit fantasies.
That does sound illicit!

But think about it - you could market this as a "Chainsaw Spin" session. No trap needed, reckon plenty of gym bunnies would pay you for the privilege
User avatar
Cugel
Posts: 5430
Joined: 13 Nov 2017, 11:14am

Re: Chain slipping Between Chainrings

Post by Cugel »

roubaixtuesday wrote: 23 Jun 2022, 10:13pm
Cugel wrote: 23 Jun 2022, 9:59pm
But a bicycle powered chainsaw? Hmmmm...

"excite"... ...a strong lady)

Cugel, having illicit fantasies.
That does sound illicit!

But think about it - you could market this as a "Chainsaw Spin" session. No trap needed, reckon plenty of gym bunnies would pay you for the privilege
That's a good idea! There'll have to be rules, though, concerning dress, behaviour and not nicking my lovely tools from their cupboards, drawers and magnetic rails.

My main concern will be the flying sweat, which won't do my steel tools any good, eh? Perhaps I could go 'round the frantically pedalling members with a rubbing towel?

How much should I charge the dafties that respond to my cunning adverts, which will tell lies and have pictures of fine muscled & bronzed fellows as well as brazenly seductive glamour pusses, all dressed in de rigeur tight lycra with a vaguely cycling theme; and smiling broadly with American teef?

Cugel
“Practical men who believe themselves to be quite exempt from any intellectual influence are usually the slaves of some defunct economist”.
John Maynard Keynes
Valbrona
Posts: 2696
Joined: 7 Feb 2011, 4:49pm

Re: Chain slipping Between Chainrings

Post by Valbrona »

I've come to this thread late ... but Tiagra triple FD will not work with a 36 middle and 46 outer. Not enough of a jump.
I should coco.
User avatar
531colin
Posts: 16083
Joined: 4 Dec 2009, 6:56pm
Location: North Yorkshire

Re: Chain slipping Between Chainrings

Post by 531colin »

Mick F wrote: 23 Jun 2022, 7:55pm
iandusud wrote: 23 Jun 2022, 3:59pm ..................
I assume that a wider chain (9 speed) wouldn't work with a 10 speed cassette.
Of course not.
My issue was swapping a 10sp Connex chain for a 10sp Campag one.
Indexing was, and still is perfect but the Campag chain, being narrower, would often sit between the outer and middle rings, and the cranks would spin................
If nominally 10 speed chains from different manufacturers are different widths, what is the basis for the assertion that a 9 speed chain won't work on a 10 speed setup?

I have a couple of 8 speed bikes and only one 9 speed. The 9 speed bike works perfectly fine with an 8 speed chain, and always has done, because when I built it up I thought it would be easier for spares if they all ran the same "8 speed" chain. (which has been whatever was around at Spa at the time....originally Connex I think, recently KMC
Mine are all friction front shift, I guess its possible that an indexed front shift (and trim) wouldn't cope with a wider chain, but I wouldn't write it off without trying it.

What is the (nominal) difference in chain widths, does anybody know where we might find the information?
Some information here......https://en.wikipedia.org/wiki/Bicycle_chain
Jdsk
Posts: 24640
Joined: 5 Mar 2019, 5:42pm

Re: Chain slipping Between Chainrings

Post by Jdsk »

531colin wrote: 24 Jun 2022, 12:06pmWhat is the (nominal) difference in chain widths, does anybody know where we might find the information?
Some information here......https://en.wikipedia.org/wiki/Bicycle_chain
Also here:

https://sheldonbrown.com/gloss_ch.html
https://www.statecyclist.com/bike-chain-size-chart/

But that Wikipedia page looks the most complete so far.

Jonathan
peetee
Posts: 4292
Joined: 4 May 2010, 10:20pm
Location: Upon a lumpy, scarred granite massif.

Re: Chain slipping Between Chainrings

Post by peetee »

Valbrona wrote: 24 Jun 2022, 11:56am I've come to this thread late ... but Tiagra triple FD will not work with a 36 middle and 46 outer. Not enough of a jump.
Hmmmm. Heard of this problem on an up shift when the inner plates shift ramp is in the wrong place but a downshift, with a flat outer plate doing the push???
The older I get the more I’m inclined to act my shoe size, not my age.
Valbrona
Posts: 2696
Joined: 7 Feb 2011, 4:49pm

Re: Chain slipping Between Chainrings

Post by Valbrona »

I'm guessing Mr OP might have positioned the FD higher than recommended in order to prevent the inner cage from hitting the middle c'ring when shifting from middle to outer.
I should coco.
iandusud
Posts: 1577
Joined: 26 Mar 2018, 1:35pm

Re: Chain slipping Between Chainrings

Post by iandusud »

Valbrona wrote: 24 Jun 2022, 11:56am I've come to this thread late ... but Tiagra triple FD will not work with a 36 middle and 46 outer. Not enough of a jump.
I know that Shimano recommend an 11t difference but I can assure you that it will work perfectly with 10t difference. The problem is related to the amount of travel.
slowster
Moderator
Posts: 4629
Joined: 7 Jul 2017, 10:37am

Re: Chain slipping Between Chainrings

Post by slowster »

I wonder if raising the derailleur by 2mm-4mm might be enough to make the shifts work cleanly. Indexing works by always moving the the derailleur cage on its pivot by the same angle. Placing the pivot point of the cage a bit further away from the chain may increase the distance which the cage moves the chain when downshifting by just enough to stop the chain falling between the chainrings.

Edit - Ignore this as it is garbage. There are two pivots and the cage moves horizontally through the same distance for any given amount of cable pull..
iandusud
Posts: 1577
Joined: 26 Mar 2018, 1:35pm

Re: Chain slipping Between Chainrings

Post by iandusud »

slowster wrote: 25 Jun 2022, 8:19am I wonder if raising the derailleur by 2mm-4mm might be enough to make the shifts work cleanly. Indexing works by always moving the the derailleur cage on its pivot by the same angle. Placing the pivot point of the cage a bit further away from the chain may increase the distance which the cage moves the chain when downshifting by just enough to stop the chain falling between the chainrings.

Edit - Ignore this as it is garbage. There are two pivots and the cage moves horizontally through the same distance for any given amount of cable pull..
Ha ha. Your efforts are appreciated. :)
Post Reply