Yet Another Cycling Forum

General Category => The Knowledge => Topic started by: Chris S on April 17, 2018, 04:18:59 pm

Title: Maximum gear capacity / chain length
Post by: Chris S on April 17, 2018, 04:18:59 pm
I've entered Deano's Most Excellent off-road 100, but I'm a right fat fucker at the moment, so I need to gear my CAADX down from the 11-28 11sp cassette it comes with. I'm looking at a Shimano 11-42 MTB cassette, but I'm kind of concerned there won't be the capacity for that. The front has 46/36.

Am I right to be concerned?*

* About the gearing, that is - I know I'm right to be concerned about being a right fat fucker.

Title: Re: Maximum gear capacity / chain length
Post by: Si S on April 17, 2018, 04:32:47 pm
Need to know what rear mech model and cage length Chris, but I doubt you'll get to 42 unless you've got an MTB mech on the back.
Title: Re: Maximum gear capacity / chain length
Post by: Chris S on April 17, 2018, 04:35:29 pm
Need to know what rear mech model and cage length Chris, but I doubt you'll get to 42 unless you've got an MTB mech on the back.

It's a 105 - it's all 105. Would it help if I measured it?
Title: Re: Maximum gear capacity / chain length
Post by: Brucey on April 17, 2018, 04:41:16 pm
you can get 42T sprocket capability by using a wolf tooth roadlink derailleur hanger extender (or similar) with a 105 long cage mech.

Total capacity may or may not be adequate...

cheers

Title: Re: Maximum gear capacity / chain length
Post by: Chris S on April 17, 2018, 04:43:28 pm
Sounds like 42 is probably a tad ambitious then.
Title: Re: Maximum gear capacity / chain length
Post by: Brucey on April 17, 2018, 04:49:16 pm
dunno, you don't have a huge chainring capacity to worry about and AFAICT the roadlink gizmo slightly increases the total capacity of the mech as well as the max sprocket size. I'd try it and see; with the chainset so you can use big-big the worst case is that you can't use the small-small combinations without the chain running slack, but you don't need to use those anyway.

cheers
Title: Re: Maximum gear capacity / chain length
Post by: cygnet on April 17, 2018, 04:54:40 pm
https://bicycles.stackexchange.com/a/51589 (https://bicycles.stackexchange.com/a/51589)  ;D for the SHOUTING

Sheldon says similar but more eloquently.

Title: Re: Maximum gear capacity / chain length
Post by: Si S on April 17, 2018, 04:57:36 pm
Need to know what rear mech model and cage length Chris, but I doubt you'll get to 42 unless you've got an MTB mech on the back.

It's a 105 - it's all 105. Would it help if I measured it?

Getting there  :)  what speed? short mech cage (SS) or long (GS), that'll be stamped on it.

If it's 11 speed and the GS mech, max, sprocket according to shimano is 32, who are notoriously conservative on spec, although I have heard tell of 36 being squeezed in, but then you're 4 teeth beyond the chainwrap capacity so little/little would be a problem, not a massive one, you'd know it wasn't happy by the racket.

x-post
Title: Re: Maximum gear capacity / chain length
Post by: Chris S on April 17, 2018, 05:02:10 pm
Small/Small is something I've trained myself out of - it could end up in a tangley mess on the tandem...  :hand:
Title: Re: Maximum gear capacity / chain length
Post by: psyclist on April 17, 2018, 05:02:49 pm
The alternative would be to downsize the chainrings, presumably a non-Shimano option would be needed.

I ran a 1x setup at the Yr Elenydd recently, and found the 42x11 to be more than adequate for the faster bits of riding (I freewheel in any case when going suitably fast!), and the 42x42 was good for the uphill bits. I'll be trying out a 36 tooth chainring if I make it up for Deano's ride.

So a chainring combination of 40/26 or similar might work ok for you, as an alternative option.
Title: Re: Maximum gear capacity / chain length
Post by: quixoticgeek on April 17, 2018, 05:37:21 pm
I've entered Deano's Most Excellent off-road 100, but I'm a right fat fucker at the moment, so I need to gear my CAADX down from the 11-28 11sp cassette it comes with. I'm looking at a Shimano 11-42 MTB cassette, but I'm kind of concerned there won't be the capacity for that. The front has 46/36.

Note that the rear mech of 105, Ultegra, and Dura Ace are interchangable (some rumour the Tiagra 4700 to also be interchangable). I think there is an Ultegra rear mech that will accept a 34 at the rear. I have the GS version of the tiagra 4700, and I have a 11-34 rear cassette.

Of all the parts that can be changed, the rear mech is relatively* affordable.

*for values of affordable
Quote

* About the gearing, that is - I know I'm right to be concerned about being a right fat fucker.

As a fellow person of substantial mass, I can recommend ambitious bike adventures as a way to lose weight. I lost 3.5kg in a single 7 day trip through Germany...

The alternative would be to downsize the chainrings, presumably a non-Shimano option would be needed.

I ran a 1x setup at the Yr Elenydd recently, and found the 42x11 to be more than adequate for the faster bits of riding (I freewheel in any case when going suitably fast!), and the 42x42 was good for the uphill bits. I'll be trying out a 36 tooth chainring if I make it up for Deano's ride.

So a chainring combination of 40/26 or similar might work ok for you, as an alternative option.

So on my frankenbike, which is based on a Genesis Vagabond, I couldn't fit my planned 50/34 front chainset on, so ended up with a mountain bike chainset. I have a Deore 40/28 on the front, with the matching front derailure, which is driven by tiagra 4700 shifters. Officially this is a combo that Will Not Work™, but the reality is, I've done 2760km on this setup and it's worked so far.

Even with a 28-34 bottom gear, I still struggle on some hills, but that's due to the aforementioned excess kummerspek, and I hope to resolve this in due course...

J
Title: Re: Maximum gear capacity / chain length
Post by: LMT on April 17, 2018, 07:05:57 pm
I currently run a 40/23 with a 11-46 on the rear with an Ultegra Shadow rear mech with a wolf link. No dramas at all and it will go large large (just). Not that I run it in that config.
Title: Re: Maximum gear capacity / chain length
Post by: Chris S on April 17, 2018, 07:14:56 pm
Is this the chap then?

https://www.amazon.co.uk/Wolf-Tooth-Roadlink-Bikes-Black/dp/B013ZTTEJK/ref=sr_1_9?ie=UTF8&qid=1523988822&sr=8-9&keywords=wolf+tooth
Title: Re: Maximum gear capacity / chain length
Post by: LMT on April 17, 2018, 07:25:51 pm
^ Yep, takes 5 minutes to fit and adjust.
Title: Re: Maximum gear capacity / chain length
Post by: quixoticgeek on April 17, 2018, 07:29:39 pm

Note, wolftooth have free delivery worldwide, if you spend $50. Given the exchange rate, if you want some other stuff from them, then it's going to be cheaper to get it direct (tho slower).

I like their B-RAD stuff, and their tools.

J
Title: Re: Maximum gear capacity / chain length
Post by: Chris S on April 17, 2018, 07:45:14 pm
^ Yep, takes 5 minutes to fit and adjust.

 :thumbsup: Thanks!
Title: Re: Maximum gear capacity / chain length
Post by: Brucey on April 17, 2018, 09:48:23 pm
'or similar'

https://www.sjscycles.co.uk/gear-spares/aluminum-rear-derailleur-hanger-extender/ (https://www.sjscycles.co.uk/gear-spares/aluminum-rear-derailleur-hanger-extender/)

https://www.ebay.co.uk/sch/i.html?_nkw=bicycle+rear+derailleur+hanger+extension+extender+mtb+cycling+frame+tail+hook (https://www.ebay.co.uk/sch/i.html?_nkw=bicycle+rear+derailleur+hanger+extension+extender+mtb+cycling+frame+tail+hook)

cheers
Title: Re: Maximum gear capacity / chain length
Post by: jiberjaber on April 17, 2018, 09:55:21 pm
18bikes also supply wolf link (where I got mine).

Tiagra will take 36 (wot I has on my CdF, 10spd though but).

11 spd Ultegra (GS) will take 34 (HG800 currently on the Jack) but it sacrifices some jumps in the upper gears 11-20 area. http://www.chainreactioncycles.com/shimano-ultegra-r8000-11-speed-cassette-11-34/rp-prod161362


If you want to downsize teh crankset, absolute black do a sub-compact setup for Shimano hollowtech cranks, either 30/46 or 32/48  I am pondering the 32/48 but can't seem to get my head around what that gives me relative to what I have now... I'm thinking the spinner 30/46 might be more suited to Moor Gravel but unsure.....

https://absoluteblack.cc/oval-road-chainrings-30-46-and-32-48-for-110-4bcd/
Title: Re: Maximum gear capacity / chain length
Post by: Deano on April 17, 2018, 10:03:46 pm
How low are the gears on the tandem, Chris?
Title: Re: Maximum gear capacity / chain length
Post by: quixoticgeek on April 17, 2018, 10:30:11 pm
18bikes also supply wolf link (where I got mine).

Tiagra will take 36 (wot I has on my CdF, 10spd though but).

How much fettling and fiddling is needed to go from a 11-34 to and 11-36 cassette do you think? I'm going to replace my cassette after the next chain (hopefully in ≥2Mm time), and sticking an 11-36 would perhaps make the Ardennes a tad easier when fully loaded...

Quote

11 spd Ultegra (GS) will take 34 (HG800 currently on the Jack) but it sacrifices some jumps in the upper gears 11-20 area. http://www.chainreactioncycles.com/shimano-ultegra-r8000-11-speed-cassette-11-34/rp-prod161362


If you want to downsize teh crankset, absolute black do a sub-compact setup for Shimano hollowtech cranks, either 30/46 or 32/48  I am pondering the 32/48 but can't seem to get my head around what that gives me relative to what I have now... I'm thinking the spinner 30/46 might be more suited to Moor Gravel but unsure.....

https://absoluteblack.cc/oval-road-chainrings-30-46-and-32-48-for-110-4bcd/

I have not yet used any Absolute Black kit, but I've had some really interesting and helpful email exchanges with them in the last couple of weeks. Their customer service seems excellent. I'm seriously considering the 46/30 set on my next bike. I'm waiting to see if the rumours of a power meter compatible version is true.

If not, then FSA make a 46/30 crankset, tho it requires it's own bottom bracket... It does seem to be relatively cost effective as an option.

J
Title: Re: Maximum gear capacity / chain length
Post by: jiberjaber on April 17, 2018, 11:59:58 pm
Fairly easy fit but there was an issue with the alignment of the cassette and the chain but after I'd reset the cassette back on the free wheel and retorqued it was fine.  I bought the MTB version and was worried I had created myself a problem in doing so but it was just not fully home.  I'll confirm which version I bought in the morning.

ETA: Shimano Dyna-Sys SLX 10 Speed Cassette Silver 11-36
Title: Re: Maximum gear capacity / chain length
Post by: frankly frankie on April 18, 2018, 08:32:36 am
I currently run a 40/23 with a 11-46 on the rear with an Ultegra Shadow rear mech with a wolf link. No dramas at all and it will go large large (just). Not that I run it in that config.

23 --> 46   :o
Title: Re: Maximum gear capacity / chain length
Post by: mzjo on April 18, 2018, 09:31:21 am
I currently run a 40/23 with a 11-46 on the rear with an Ultegra Shadow rear mech with a wolf link. No dramas at all and it will go large large (just). Not that I run it in that config.

23 --> 46   :o

^  Surely that's gone past the stage where it's quicker to get off and walk (or do you just not like getting your feet wet :) )
Title: Re: Maximum gear capacity / chain length
Post by: Si S on April 18, 2018, 09:36:44 am
I currently run a 40/23 with a 11-46 on the rear with an Ultegra Shadow rear mech with a wolf link. No dramas at all and it will go large large (just). Not that I run it in that config.

23 --> 46   :o

^  Surely that's gone past the stage where it's quicker to get off and walk (or do you just not like getting your feet wet :) )

I think LMT is a recumbentist and they're not the easiest things to push
Title: Re: Maximum gear capacity / chain length
Post by: jiberjaber on April 18, 2018, 10:38:28 am
Here's some comparisons on the absolute black I've been playing with.  This is comparing with a compact 34/50 matched with a HG800 11-34

For the 30/46 AB rings, thats sort of like having an 12-38 on a 34/50 :
http://www.ritzelrechner.de/?GR=DERS&KB=30,46&RZ=11,13,15,17,19,21,23,25,27,30,34&UF=2185&TF=80&SL=2.5&UN=KMH&GR2=DERS&KB2=34,50&RZ2=12,13,15,17,19,21,23,25,27,30,34,38&UF2=2161

For the 32/48 AB rings, thats sort of like having an 11-36 on a 34/50:
http://www.ritzelrechner.de/?GR=DERS&KB=32,48&RZ=11,13,15,17,19,21,23,25,27,30,34&UF=2185&TF=80&SL=2.5&UN=KMH&GR2=DERS&KB2=34,50&RZ2=11,13,15,17,19,21,23,25,27,30,34,36&UF2=2161

Obs tyre width has an impact on final feal (increase width, increases the gear-inches further etc)
 
Pros: lower gear, cool looking rings, opportunity to see if oval does make a difference etc
Cons: more expensive than a wider cassette (?), because of the offset bolts, no bolt covers when fitted, because of the offset bolts, may need a specific chain (according to AB but surely all chains still have the same dimensions so maybe not an issue?)

I am erring towards the 30/46 but still need to ponder where there is duplication on the gear-inches and how that impacts my synchronous DI2....

ETA: So a set of AB = £171 or a roadlink plus cassette = £77 (roadlink = £22, Cassette £56)
Title: Re: Maximum gear capacity / chain length
Post by: jiberjaber on April 18, 2018, 10:49:36 am
I've entered Deano's Most Excellent off-road 100, but I'm a right fat fucker at the moment, so I need to gear my CAADX down from the 11-28 11sp cassette it comes with. I'm looking at a Shimano 11-42 MTB cassette, but I'm kind of concerned there won't be the capacity for that. The front has 46/36.

Am I right to be concerned?*

* About the gearing, that is - I know I'm right to be concerned about being a right fat fucker.

Wolf link and that cassette would compare like a compact and 12-36 cassette (though unable to help on how much more chain you would need):
http://www.ritzelrechner.de/?GR=DERS&KB=36,46&RZ=11,13,15,17,19,21,24,28,32,37,42&UF=2192&TF=80&SL=2.5&UN=KMH&GR2=DERS&KB2=34,50&RZ2=12,13,15,17,19,21,23,25,27,30,34,39&UF2=2192


Here's a comparison of 11-28 vrs that cassette:
http://www.ritzelrechner.de/?GR=DERS&KB=36,46&RZ=11,13,15,17,19,21,24,28,32,37,42&UF=2192&TF=80&SL=2.5&UN=KMH&GR2=DERS&KB2=36,46&RZ2=11,12,13,14,15,17,19,21,23,25,28&UF2=2192
Title: Re: Maximum gear capacity / chain length
Post by: fboab on April 18, 2018, 03:15:40 pm
How low are the gears on the tandem, Chris?

Hahahahahhhahahahahahahaha

He's not the only fat fucker entered.

I might buy a new bike. With a motor.
Title: Re: Maximum gear capacity / chain length
Post by: LMT on April 18, 2018, 07:13:34 pm
I currently run a 40/23 with a 11-46 on the rear with an Ultegra Shadow rear mech with a wolf link. No dramas at all and it will go large large (just). Not that I run it in that config.

23 --> 46   :o

^  Surely that's gone past the stage where it's quicker to get off and walk (or do you just not like getting your feet wet :) )

I built up the bike with the purpose of long distance hilly events, rather embarrasingly I've yet to tackle a hill on the bike with this set up but simulating a 20% grad on the Tacx Neo I'm looking at a cadence of just over 90rpm and just under 200 watts with 23*32. Well within threshold, spinning to win.

And 40*11 means the bike will still go at a fair lick, going down hills on a bent you are natuarally faster due to better aero so not bothered about spinning out.
Title: Re: Maximum gear capacity / chain length
Post by: Somnolent on April 18, 2018, 08:56:09 pm
Chris
Do you have the wherewithal to bodge up a 'super-compact' like this (https://yacf.co.uk/forum/index.php?topic=106051.0)?
Running an 11-32 cassette with a 105 set up (5800GS rear mech) quite happily.
Title: Re: Maximum gear capacity / chain length
Post by: ElyDave on April 19, 2018, 12:57:10 pm
Are shimano MTB and road cassettes cross compatible? I.e will an MTB cassette work with my 105 derailleur and ultegra shifter? 10sp BTW.
Title: Re: Maximum gear capacity / chain length
Post by: jiberjaber on April 19, 2018, 02:57:40 pm
Are shimano MTB and road cassettes cross compatible? I.e will an MTB cassette work with my 105 derailleur and ultegra shifter? 10sp BTW.

Seems to be compatible with my Tiagra RD, 105 shifters and chainset.  When I was having problems with the chain jumping on the cassette I assumed it was because I hadn't used the dynasys slx mtb specific chain and bought one to replace the standard 10spd road chain I had put on.  When I compared the two chains they were exactly the same dimensions so I decided to remove and refit the cassette which then resolved the jumping!
Title: Re: Maximum gear capacity / chain length
Post by: ElyDave on April 19, 2018, 03:16:08 pm
Are shimano MTB and road cassettes cross compatible? I.e will an MTB cassette work with my 105 derailleur and ultegra shifter? 10sp BTW.

Seems to be compatible with my Tiagra RD, 105 shifters and chainset.  When I was having problems with the chain jumping on the cassette I assumed it was because I hadn't used the dynasys slx mtb specific chain and bought one to replace the standard 10spd road chain I had put on.  When I compared the two chains they were exactly the same dimensions so I decided to remove and refit the cassette which then resolved the jumping!

Ta, I'm looking for a lower gearing option for the cruzbike for the summer tour. It was OK last weekend in the 30 x 28, but I think a 32 might be better with load
Title: Re: Maximum gear capacity / chain length
Post by: jiberjaber on April 19, 2018, 03:26:32 pm
Are shimano MTB and road cassettes cross compatible? I.e will an MTB cassette work with my 105 derailleur and ultegra shifter? 10sp BTW.

Seems to be compatible with my Tiagra RD, 105 shifters and chainset.  When I was having problems with the chain jumping on the cassette I assumed it was because I hadn't used the dynasys slx mtb specific chain and bought one to replace the standard 10spd road chain I had put on.  When I compared the two chains they were exactly the same dimensions so I decided to remove and refit the cassette which then resolved the jumping!

Ta, I'm looking for a lower gearing option for the cruzbike for the summer tour. It was OK last weekend in the 30 x 28, but I think a 32 might be better with load

There's Tiagra 10sp cassettes up to 34 if you want to be super confident of it working (this is what I had on before - I only went lower to help spin more on uneven ground)
Title: Re: Maximum gear capacity / chain length
Post by: ElyDave on May 04, 2018, 10:25:13 pm
Went with the 12-32 in the end, been riding it this week much better. Been spending far more time in the big ring on the flat