11-28 to 11-34 road bike upgrade : Update !

For discussions about bikes and equipment.
TheBomber
Posts: 525
Joined: 16 Feb 2020, 8:18pm

Re: 11-28 to 11-34 road bike upgrade

Post by TheBomber »

Do any of the in-line adjusters have springs and detents in them to stop them self adjusting? I had a regular one on the cable between shifter and head tube stop (for a front mech) but it seemed to screw itself back in due to the movement from steering. I’ve had less bother since getting rid of it but doubt that’s a solution for a rear mech.
User avatar
cycleruk
Posts: 6065
Joined: 17 Jan 2009, 9:30pm
Location: Lancashire

Re: 11-28 to 11-34 road bike upgrade

Post by cycleruk »

Valbrona wrote: 19 May 2022, 9:16pm But Shimano MTB mechs do not have cable adjuster.
Some do as can be seen (if you look closely :wink: ) on my 10 speed 105 with a 9 speed MTB mech'.
Using 12/34 cassette and 50/39/30 triple. Works flawlessly.
https://www.chainreactioncycles.com/shi ... -prod40543
(Unfortunately out of stock - I paid £9 for this a few years back :shock: )
genisis.JPG
You'll never know if you don't try it.
User avatar
Mick F
Spambuster
Posts: 56359
Joined: 7 Jan 2007, 11:24am
Location: Tamar Valley, Cornwall

Re: 11-28 to 11-34 road bike upgrade

Post by Mick F »

audaxjk wrote: 19 May 2022, 12:48pm The Groupset has an 11-28 cassette & a 6700 short cage derailleur. Ideally, I would like to go to 11-34 on the new build.
This "fashion" for 11t sprockets and correspondingly smaller chainwheels is a very bad idea IMO.

Fit a cassette with the smallest sprocket 12t and fit a bigger chainwheel. They last far longer.
Mick F. Cornwall
audaxjk
Posts: 155
Joined: 2 Mar 2020, 4:45pm

Re: 11-28 to 11-34 road bike upgrade

Post by audaxjk »

Once again many thanks for all the ongoing help/advice - absolutely brilliant!
TheLastMan
Posts: 18
Joined: 21 Oct 2019, 8:56am
Location: Hounslow

Re: 11-28 to 11-34 road bike upgrade

Post by TheLastMan »

Thought I would revive this thread rather than start a new one, as my query is very similar.

Like the OP, I am rather old, and would like an easier gear to allow me to go slower up the steepest hills rather than just fall off sideways as I currently do! My riding style is endurance (AUDAX etc) so ultimate speed is not important.

My Trek Domane AL4 with Tiagra 10 speed groupset currently has an 11-32 cassette. There is a 10 speed 11-34 cassette option available for Tiagra. The spec for the bike says "Shimano Tiagra 4700, long cage, 34T max cog". Would it make an appreciable difference changing to 11-34? (I am in the small front sprocket far more than the big one!)

If so, would I need a new chain? Somebody mentioned needing to add a couple of links - can you buy spare links? Any other installation potential pitfalls I should look out for?

Thanks for any help!
rareposter
Posts: 1992
Joined: 27 Aug 2014, 2:40pm

Re: 11-28 to 11-34 road bike upgrade

Post by rareposter »

TheLastMan wrote: 23 May 2022, 4:35pm
My Trek Domane AL4 with Tiagra 10 speed groupset currently has an 11-32 cassette. There is a 10 speed 11-34 cassette option available for Tiagra. The spec for the bike says "Shimano Tiagra 4700, long cage, 34T max cog". Would it make an appreciable difference changing to 11-34? (I am in the small front sprocket far more than the big one!)

If so, would I need a new chain? Somebody mentioned needing to add a couple of links - can you buy spare links? Any other installation potential pitfalls I should look out for?

Thanks for any help!
A new cassette should just go straight on. Might need the b-tension screw adjusting a bit to allow the rear mech to clear it.
Gear ratio wise, you drop about 2" which isn't a huge amount but is noticeable.
Chain - if you're fitting a new cassette, fit a new chain. Faffing around trying to fit new links into a chain of indeterminate age / wear is just asking for trouble. Save yourself the time and hassle, get a new chain with it, your entire drivetrain will thank you for it.
Tiggertoo
Posts: 475
Joined: 2 Jun 2021, 4:52pm

Re: 11-28 to 11-34 road bike upgrade

Post by Tiggertoo »

rather than just fall off sideways as I currently do
Definitely a realistic option to spending a lot more money on new gearing. :P
audaxjk
Posts: 155
Joined: 2 Mar 2020, 4:45pm

Re: 11-28 to 11-34 road bike upgrade : Update !

Post by audaxjk »

Hi all, I thought that I would provide an update to my original post here and ask for a little bit of further advice!!

Thanks especially to Hamster, Keyboardmonkey, rareposter, MickF and Fausto99 for really useful advice.

So I built up my bike with a 48/32 FSA chainset and 11-36 cassette giving a really great range of gearing for my needs. Taking the advice from above I used a (second hand) 9 speed Shimano SLX shadow rear mech to run the wide ratio cassette with Shimano 105 5700 10 speed shifters and as suggested put in an inline barrel adjuster. The wheels are my own hand built ones.

The bike runs really sweet (the Juin Tech disc brakes work almost as good as full hydraulics with jagwire compressionless cables), except for one minor gripe for which advice/thoughts would be appreciated! The rear mech does shift across the cassette but it's not 100% perfect. It doesn't shift up from the 11 tooth to 12 tooth all the time and usually I have to click again on the sti to put it onto the 3rd cog. Also the upshift from the 24t to 28T cog sometimes gets bypassed and goes up to the (next 32T) cog.

I can live with this, but I usually build my bikes to perfection, so this is niggling away at me! Despite adjusting the high/low screws and cable tension on the barrel adjuster, I just cannot get it perfect. The rear hub is 11 speed and as such I have 1 spacer on the freehub body. Any suggestions, could the rear mech be faulty (It was a 2nd hand ebay purchase)?
Attachments
IMG_5029.JPG
IMG_5028.JPG
User avatar
Tigerbiten
Posts: 2503
Joined: 29 Jun 2009, 6:49am

Re: 11-28 to 11-34 road bike upgrade : Update !

Post by Tigerbiten »

The constant odd mis shift could well be caused by the mech hanger being slightly bent.
Look up how to check that it's not and test it.

Luck ....... :D
slowster
Moderator
Posts: 4629
Joined: 7 Jul 2017, 10:37am

Re: 11-28 to 11-34 road bike upgrade : Update !

Post by slowster »

One of the most likely causes is a (slightly) misaligned/bent derailleur hanger. Unless you have a suitable alignment tool, this is usually something you need to get your local bike shop to check and fix. That said there are ways of doing it without a proper tool, e.g. using a spare wheel by screwing the axle into the dropout, and then using the spare wheel to check for alignment (parallel to the existing wheel) and to re-align/bend the dropout if necessary.

If you don't have a suitable tool, a good quick way to check is to fit a new derailleur hanger* and see if that makes a difference: if it does, that is a good indication that that is the problem. It's always advisable to have a spare derailleur hanger anyway. Incidentally, I think a lot of bike shop mechanics report that even a new hanger might not give perfect shifting, and might need fine tuning when installed.

Park Tool video link below:

https://www.parktool.com/en-int/blog/re ... -alignment

R J The Bike Guy's video on doing it without a proper tool:

https://www.youtube.com/watch?v=TnwreRrorIA

* If you need to buy a spare, you'll need to check the various hangers listed on Kinesis' website to find the one for your particular frame, e.g.

https://www.kinesisbikes.co.uk/Catalogu ... /Dropout-3
audaxjk
Posts: 155
Joined: 2 Mar 2020, 4:45pm

Re: 11-28 to 11-34 road bike upgrade : Update !

Post by audaxjk »

Ah yes, thank you! Forgot about that - I do have an alignment tool buried in the garage somewhere. Will fish it out and remind myself how to use it!
Post Reply