Cannondale mtb / fixie

For discussions about bikes and equipment.
Post Reply
Paulie73
Posts: 17
Joined: 9 Feb 2025, 9:31pm

Cannondale mtb / fixie

Post by Paulie73 »

Hi all I have a 26 inch cannondale mtb and want to upgrade the crank ?currently it has a 3 x drivetrain. I would like a 1x drive train any recommendations on what size crank for speed and hills ? Also have a fixed gear bike in need of rebuild but unsure on cranksize for speed and getting up hills ?
rogerzilla
Posts: 3173
Joined: 9 Jun 2008, 8:06pm

Re: Cannondale mtb / fixie

Post by rogerzilla »

Crank size should be a function of thigh length. Choose appropriate gearing rather than trying to choose different length cranks for leverage.

For a fixie, 165mm cranks have the advantage of reducing the risk of pedal strike on corners.
TheBomber
Posts: 634
Joined: 16 Feb 2020, 8:18pm

Re: Cannondale mtb / fixie

Post by TheBomber »

I suspect the OP means ‘what size chainring’, but I may be mistaken. If not, then just ride your bike as is and take note of which gears you use front and rear to work out what range you require. If necessary return here with the detail of the sizes of the chainings and cassette sprockets ridden and you’ll be able to get some helpful advice on setups that should work for you.
Paulie73
Posts: 17
Joined: 9 Feb 2025, 9:31pm

Re: Cannondale mtb / fixie

Post by Paulie73 »

Thanks my largest outer chain ring is a 42t rear cassette is 10 speed ! I would like to change to single chain ring like on most mountain bikes now but keeping in mind what size ring to fit ?
User avatar
geomannie
Posts: 1267
Joined: 13 May 2009, 6:07pm

Re: Cannondale mtb / fixie

Post by geomannie »

Your question is a bit "how long is a piece of string" but I'll give you the benefit of my recent conversation from a triple to a single.

Firstly, I am cheerfully retired so my strength is not what it was. I'm now more a spinner than a slogger. In other words I like low gears.

Quite a few 1x systems will use a 40T chainring and a massive rear 12 speed cassette, perhaps 11-50T (eg https://www.bikeradar.com/reviews/compo ... gle-review). This gives a wide range of gears, albeit with fair sized jumps.

I took a slightly different route. I don't want higher gears so I chose a 34T chainring and an 11-40T 10 speed cassette. In top gear I'm spinning out in the high 20's mph so plenty fast for me. Bottom gear is plenty low too.

My main question to you is how do you plan to shift the new rear derailleur/cassette combo? An indexed system will be pricey. I opted for a friction system so I was able to mix up some supposedly incompatible items. Also consider the number is speeds your wheel will take. If it's an older wheel you might struggle to fit an 11/12 speed cassette, but someone more knowledgeable can possibly comment on this?
geomannie
hamster
Posts: 4226
Joined: 2 Feb 2007, 12:42pm

Re: Cannondale mtb / fixie

Post by hamster »

A 2:1 ratio front to rear is a good starting point for MTB singlespeeding.
The big factors are the terrain and your fitness!

I run 32/17 or 40/21.
Brucey
Posts: 47386
Joined: 4 Jan 2012, 6:25pm

Re: Cannondale mtb / fixie

Post by Brucey »

Paulie73 wrote: 10 Feb 2025, 9:30am.......I would like to change to single chain ring like on most mountain bikes now.....
baaaa! .....whatever happened to independent thought?

What parts need changing on the fixie?
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
rareposter
Posts: 3465
Joined: 27 Aug 2014, 2:40pm

Re: Cannondale mtb / fixie

Post by rareposter »

Paulie73 wrote: 10 Feb 2025, 9:30am Thanks my largest outer chain ring is a 42t rear cassette is 10 speed ! I would like to change to single chain ring like on most mountain bikes now but keeping in mind what size ring to fit ?
Surely that'll depend on what gears you currently have on your 3x10, what gears you use the most, what terrain you're riding, your ability (inc age, fitness, weight, riding style) and your average speed....?

I'm assuming that if you've got a 42T outer chainring, you've probably got 22/32 as inner/middle so 32T would be the logical place to start. Can go a bit bigger if you're riding flatter terrain, if you're younger/fitter/stronger; might want a bit smaller if you're riding steeper terrain or you're towards the older/less fit end of the spectrum or routinely carrying luggage for example.
Some of that will depend on the ratios on the cassette, my guess, on a 3x10 is it's probably an 11-34 / 11-36 at most.

Note that you'll need a proper 1x (narrow wide) chainring.
Paulie73
Posts: 17
Joined: 9 Feb 2025, 9:31pm

Re: Cannondale mtb / fixie

Post by Paulie73 »

Reply about the single speed fixie that needs a new crank and rear wheel cog but unsure of what gearing ratio to put on it for flat terrain and some hills ! I bought the bike second hand like this ?
User avatar
Chris Jeggo
Posts: 694
Joined: 3 Jul 2010, 9:44am
Location: Surrey

Re: Cannondale mtb / fixie

Post by Chris Jeggo »

Paulie73 wrote: 11 Feb 2025, 9:16am Reply about the single speed fixie that needs a new crank and rear wheel cog but unsure of what gearing ratio to put on it for flat terrain and some hills ! I bought the bike second hand like this ?
To change the gear ratio of a fixie, it's usually easier, and certainly cheaper, to change the rear sprocket than the chainwheel. Experiment with different sizes and choose the one you like best.
Brucey
Posts: 47386
Joined: 4 Jan 2012, 6:25pm

Re: Cannondale mtb / fixie

Post by Brucey »

Paulie73 wrote: 11 Feb 2025, 9:16am Reply about the single speed fixie that needs a new crank and rear wheel cog but unsure of what gearing ratio to put on it for flat terrain and some hills ! ....
gearing is very much a matter of personal taste. No-one can tell you what gear suits best; it is ultimately up to you. FWIW my advice is that very commonly the chainwheel looks terrible even when it is fit for further service; this being the case, it is usually worth trying a new chain and sprocket with the old chainwheel. IME the worst that will happen is that the chainring is slightly hooked and won't run smoothly under load, temporarily anyway. If you feel that the gearing is 'close, but no cigar' maybe a slightly different size of chainring will make it perfect.
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
rareposter
Posts: 3465
Joined: 27 Aug 2014, 2:40pm

Re: Cannondale mtb / fixie

Post by rareposter »

Paulie73 wrote: 11 Feb 2025, 9:16am Reply about the single speed fixie that needs a new crank and rear wheel cog but unsure of what gearing ratio to put on it for flat terrain and some hills ! I bought the bike second hand like this ?
It would help greatly if you could expand on:
what the bike actually is
what drivetrain is currently on there and the state of it
what your experience of riding fixed on the road is (much as I've done thousands of hours on velodromes, I absolutely hate riding fixed on road, I much prefer singlespeed, where there's a freewheel)
what terrain / distance / average speed you'll be riding at.

FWIW, back in the day the "traditional" roadie clubman fixed gear (usually a winter bike) would have a ratio of about 2.6 : 1 so roughly a 42:16 although you can go a bit bigger for faster riding, something like 48:16; any higher than that and hills start to get quite problematic.
Also, any smaller than 42:16 and things get very very spinny on the descents as the pedals want to rush around at 150rpm!
Paulie73
Posts: 17
Joined: 9 Feb 2025, 9:31pm

Re: Cannondale mtb / fixie

Post by Paulie73 »

The single speed fixie I’m not sure what make it is as it’s plain but the bike can easily be fixed up into a decent bike however the front crank does need replacing as it’s buckled which again is not hard ! Also the tyres appear solid so no tubes inserted ! I’m currently using my cannondale mtb but will try the single speed bike when I’ve replaced the cranks ! I only really ride on cycle paths so no off roading hence why I’ve changed my knobbly tyres to road tyres on my cannondale mtb for time being
Brucey
Posts: 47386
Joined: 4 Jan 2012, 6:25pm

Re: Cannondale mtb / fixie

Post by Brucey »

Paulie73 wrote: 11 Feb 2025, 1:00pm....however the front crank does need replacing as it’s buckled .....
perhaps it can be straightened?
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
Post Reply