40T Cassette On A Road Bike

For discussions about bikes and equipment.
User avatar
fausto99
Posts: 953
Joined: 19 Sep 2011, 10:06am
Location: NW Kent

40T Cassette On A Road Bike

Post by fausto99 »

Following on from the "Shimano 105 B limit screw too short" thread viewtopic.php?f=5&t=146709 , I've been trying to set up my road bike as per "Katie Kookaburra's MY 40 CASSETTE ROAD BIKE SET UP" https://www.youtube.com/watch?v=Z97UDBEDFKo&t=15s

My bike had an older 105 rear mech, namely the 105 RD-5701-SS, so, a word of warning to others who might want to try this - the Wolf Tooth Goat Link (WTGL) does not work with old type Shimano 105 rear mechs. It clearly works ok for KK with her Shadow type Ultegra mech and may work with more recent Shadow 105 mechs, but it does not work with the older 105 RD-5701-SS (or longer cage -GS).

The reason is because the WTGL is about 8mm thick and STRAIGHT, you have to adjust the both end stop screws by that much to maintain the same mech movement. The high gear end stop does not cause any issues. It can be adjusted inwards 8 or so mm, no problem. The inward low gear stop, however, has to go right to the limit of its travel and at that point, you run out of cable pull because the ratio of mech travel to cable pull would appear to have reduced at such an extreme angle. If you try to wind the cable tighter to compensate, then the up shifts don't happen.

I'm going to try again with a CRANKED hanger extender (like this https://smile.amazon.co.uk/gp/product/B ... UTF8&psc=1 ) and I'll report my findings.

p.s. I'm getting very good at setting up rear derailleurs... :lol:
Eyebrox
Posts: 583
Joined: 5 Aug 2015, 8:56pm
Location: Ayrshire

Re: 40T Cassette On A Road Bike

Post by Eyebrox »

I find singlespeeds harder on hills but the extra exercise and lack of derailleur anxiety makes me sleep better. Enjoy your experimenting. 😀
User avatar
Mick F
Spambuster
Posts: 56367
Joined: 7 Jan 2007, 11:24am
Location: Tamar Valley, Cornwall

Re: 40T Cassette On A Road Bike

Post by Mick F »

Why are triples out of fashion?

Simple really.
Three sets of gears.
Rear cassette is one set, and using three chainrings gives another two sets using the same cassette.
What's not to like?
Mick F. Cornwall
Jamesh
Posts: 2963
Joined: 2 Jan 2017, 5:56pm

Re: 40T Cassette On A Road Bike

Post by Jamesh »

Mick F wrote: 19 Jul 2021, 5:16pm Why are triples out of fashion?

Simple really.
Three sets of gears.
Rear cassette is one set, and using three chainrings gives another two sets using the same cassette.
What's not to like?
Your so old fashioned Mick! bet you don't have disc brakes or tubeless tyres....get with it Mick F!!! :wink: :wink: :wink:

Cheers James
scottg
Posts: 1222
Joined: 10 Jan 2008, 8:44pm
Location: Highland Heights Kentucky,, USA

Re: 40T Cassette On A Road Bike

Post by scottg »

Jamesh wrote: 19 Jul 2021, 6:31pm
Mick F wrote: 19 Jul 2021, 5:16pm Why are triples out of fashion?

Simple really.
Three sets of gears.
Rear cassette is one set, and using three chainrings gives another two sets using the same cassette.
What's not to like?
Your so old fashioned Mick! bet you don't have disc brakes or tubeless tyres....get with it Mick F!!! :wink: :wink: :wink:

Cheers James
Mick is considering a set of those new fangled pneumatic tyres on alloy rims, to replace his solids on wooden rims.
This inflatable tube business is just another way to separate the punters from their money.
+++++++++++++++++++++++++
Deutsche Luftschiffahrts-AG
+++++++++++++++++++++++++
Tompsk
Posts: 195
Joined: 6 Nov 2014, 9:35am

Re: 40T Cassette On A Road Bike

Post by Tompsk »

Mick F wrote: 19 Jul 2021, 5:16pm Why are triples out of fashion?

Simple really.
Three sets of gears.
Rear cassette is one set, and using three chainrings gives another two sets using the same cassette.
What's not to like?
Double chainsets may be living on borrowed time too. The multi sprocket cassette is king, the more cogs the better...
User avatar
fausto99
Posts: 953
Joined: 19 Sep 2011, 10:06am
Location: NW Kent

Re: 40T Cassette On A Road Bike

Post by fausto99 »

Mick F wrote: 19 Jul 2021, 5:16pm Why are triples out of fashion?
...
What's not to like?
Nothing at all. I have four other bikes with triples (and two singlespeed ones)
Am I not allowed even one double chainring bike to play around with? :mrgreen: :lol: :wink:
David9694
Posts: 908
Joined: 10 Feb 2018, 8:42am

Re: 40T Cassette On A Road Bike

Post by David9694 »

I went the Jtech route on my gravel bike build and have an MTB rear mech and cassette running off friction downtube levers.
Spa Audax Ti Ultegra; Genesis Equilibrium 853; Raleigh Record Ace 1983; “Raleigh Competition”, “Raleigh Gran Sport 1982”; “Allegro Special”, Bob Jackson tourer, Ridley alu step-through with Swytch front wheel; gravel bike from an MB Dronfield 531 frame.
NickJP
Posts: 804
Joined: 24 Sep 2018, 7:11pm
Location: Canberra, OZ

Re: 40T Cassette On A Road Bike

Post by NickJP »

When I put together a touring bike recently using an 11-40 cassette, I used a Shimano GRX RD-RX810 rear derailleur with a Wolftooth and that copes fine with the 40t cassette. The bike has Dura-Ace 11-speed barend shifters.
gom
Posts: 67
Joined: 10 Mar 2021, 3:23pm
Location: Glos.

Re: 40T Cassette On A Road Bike

Post by gom »

Does 11-40 give a sufficient range of gear ratios? For me not, by a long way.
With an 18" bottom gear and a single chainring, the top gear will be 18*40/11 ~= 64". Too low.
User avatar
Mick F
Spambuster
Posts: 56367
Joined: 7 Jan 2007, 11:24am
Location: Tamar Valley, Cornwall

Re: 40T Cassette On A Road Bike

Post by Mick F »

Exactly that.
Single with a wide range cassette is pointless on a normal road bike. Far too small a gear-range.

Doubles are ok, and I used doubles for years and years. 52/40, 52/38 and latterly 53/36.
Since going to a triple in 2004, I wouldn't ever consider a double again.

Don't get me onto the subject of smaller cassette sprockets! 12t is the smallest I would ever consider.
Mick F. Cornwall
roubaixtuesday
Posts: 5818
Joined: 18 Aug 2015, 7:05pm

Re: 40T Cassette On A Road Bike

Post by roubaixtuesday »

Mick F wrote: 19 Jul 2021, 5:16pm Why are triples out of fashion?
Because a modern compact double gives a similar gear range with less complication, due to the much larger range on rear cassette than used to be the case.

Typical off the shelf road bike these days is 50/34 with 11-34, which for an unladen bike is perfect IMO.

Lower gearing than that only really needed for laden touring, where a triple comes in. Though even there it's more the lack of readily available (or standard) lower geared chainsets that is the issue rather than the double/triple issue. A double with, say 36/24 and 11-34 would be fine for touring.
User avatar
Mick F
Spambuster
Posts: 56367
Joined: 7 Jan 2007, 11:24am
Location: Tamar Valley, Cornwall

Re: 40T Cassette On A Road Bike

Post by Mick F »

roubaixtuesday wrote: 20 Jul 2021, 9:33am Typical off the shelf road bike these days is 50/34 with 11-34, which for an unladen bike is perfect IMO.
Say a 27" wheel.
Bottom gear 27 gear inches
Top gear 122 gear inches.

For me, it would need to be a 32t inner and a 53t outer because 11t is silly, so 12t would be better.
This would give 119" and 25" ...... far better, and the cassette would last longer too.

Trouble is, the jump from 32 to 53 is far too much ............ hence a triple.
Mick F. Cornwall
roubaixtuesday
Posts: 5818
Joined: 18 Aug 2015, 7:05pm

Re: 40T Cassette On A Road Bike

Post by roubaixtuesday »

Mick F wrote: 20 Jul 2021, 10:38am
roubaixtuesday wrote: 20 Jul 2021, 9:33am Typical off the shelf road bike these days is 50/34 with 11-34, which for an unladen bike is perfect IMO.
Say a 27" wheel.
Bottom gear 27 gear inches
Top gear 122 gear inches.

For me, it would need to be a 32t inner and a 53t outer because 11t is silly, so 12t would be better.
This would give 119" and 25" ...... far better, and the cassette would last longer too.

Trouble is, the jump from 32 to 53 is far too much ............ hence a triple.
Yeah, sure, if you want to needlessly limit yourself on cassette, and if you want a really wide gear range absolutely.

But for the vast majority of cyclists who don't carry loads of luggage around, 50/34 and 11-34 covers their needs, and a triple is unnecessary. Which is why they're out of favour.

I'm not at all against them when needed - our tandem has 46/36/24 11-36 and that would be a good setup for a laden tourer also used for general riding I think.
MartinC
Posts: 2134
Joined: 10 May 2007, 6:31pm
Location: Bredon

Re: 40T Cassette On A Road Bike

Post by MartinC »

Mick F wrote: 19 Jul 2021, 5:16pm Why are triples out of fashion?
'Cos they are. Fashion isn't rational.

In my opinion there are 2 technical factors (amongst many others) that have contributed to this. Firstly the dedicated pursuit of (unnecessary, in my view) indexing of front changes has lead to vastly over complex and finicky front mechs which only work consistently if you stick to exactly the manufacturers inflexible specs and even then only if everything is new, clean and the wind's in the right direction. So getting rid of them is attractive. The other is the proliferation of rear sprockets. Apart from wider cassettes exacerbating your front mech problems if you've got 11,12 or 13 sprockets at the rear so 3 chainrings at the front can seem redundant. Especially if you've forgotten that the technology to provide a decent range of well spaced gears with 7 or less sprockets has been around for years.

Derailleur transmissions can't evade the laws of mathematics. The percentage gaps between sprockets becomes increasingly large as the number of teeth declines so with 10, 11 and 12 tooth sprockets the gear jumps between these and the next sprocket will always be too large for me. Secondly, sprockets aren't round they're a series or 1/2" chords and as the sprocket size diminishes it becomes less round, less efficient and less hardwearing.

I ride a 1x transmission, a Rohloff. It's got 14 wide, evenly spaced gears on 42x17 with no wheel dish and a permanently good chainline. If a 1x derailleur transmission can't get anywhere near even the gear spacing to this then to me its a failed solution. The Rohloff might be expensive but the consumables are dirt cheap compared with a modern gravel bike transmission. I can also get the same, robust and reliable solution with a 3x7 transmission.

The irony isn't lost on me either - dispensing with chainrings so that you can put multiple sprockets of a similar size on the rear and dispensing with an over complex front mech by elaborating the chainring (narrow/wide, offset teeth) and the rear mech (immense articulation and a clutch) to stop the extra long chain falling off.

So to return to the OP - a 40t cassette on a road bike. Why? Presumably to compensate for some of the shortcomings in the transmission design.
Post Reply