Gearing Help

indyjones

Hi all,

I have got a SRAM Rival 46/36 chain set that I am going to pair with shimano rs685 shifters and 105 front and rear mechs.

For the rear which cage length should I go for? I like the look of the 11-32 cassette or is that over kill? Would I get away with a short cage length due to the 46teeth on the front?

Thank you

rozzer32

Are you going to be racing?

If you are then I'd stick to an 11-28 with a short cage rear mech. If you went 11-32 you'd have to get a long cage rear mech and they attract more mud and grass than a short cage. To be honest if you can't pedal a 36/28 then you'd be better off running.

Yes you will be fine with a short cage with a 46. My set up is 46/36 and 11/28 and I run a 105 5800 short cage rear mech.

tgotb

rozzer32 wrote:

To be honest if you can't pedal a 36/28 then you'd be better off running.

Not necessarily. Many's the time I've passed a runner, whilst spinning away in 38x32; so long as you have traction, riding is generally faster than running, tends to tire you out less, and depending what comes before after, can give the opportunity for smoother transitions. Horses for courses, but it can be handy to have low gearing in your armoury.

That said, rozzer's point about the short cage mech is a good one. Since 28 is the limit with Shimano, I'd go with that and consider a smaller chainring (compact will go down to 33) to get lower gearing.

Alternatively, have you considered a single chainring setup (keeping the remainder of the existing chainset)? Less weight, less to go wrong, and far superior mud clearance...

indyjones

rozzer32 wrote:

Are you going to be racing?

If you are then I'd stick to an 11-28 with a short cage rear mech. If you went 11-32 you'd have to get a long cage rear mech and they attract more mud and grass than a short cage. To be honest if you can't pedal a 36/28 then you'd be better off running.

Yes you will be fine with a short cage with a 46. My set up is 46/36 and 11/28 and I run a 105 5800 short cage rear mech.

No plan for racing yet, will be for training and hitting the local bridle ways for fun.
I will see how I get on if I get into it I will give one of the cx sportifs a go late this year and see how I get on from then on.
Already planning so big cross country rides later this year looks a lot of fun.

trek_dan

What gearing are you used to on your roadbike? if your planning some long cross country CX rides and cyclo-sportifs then you may need a low bottom gear depending on terrain, lower than your road bike for getting up off road climbs. I run a single ring on the front for racing but ride with a medium cage mech so I have the versatility to fit a MTB cassette if needed.

indyjones

trek_dan wrote:

What gearing are you used to on your roadbike? if your planning some long cross country CX rides and cyclo-sportifs then you may need a low bottom gear depending on terrain, lower than your road bike for getting up off road climbs. I run a single ring on the front for racing but ride with a medium cage mech so I have the versatility to fit a MTB cassette if needed.

I ride compact with 11-28 on the road bike and I have got a 11-34 on the mtb.
It's pretty hilly around me and my fitness is poor atm! I am thinking of going 11-28 on the cx

ShutupJens

I'd go with the 28. I used to ride a 32 cassette, 34 on the front. Even when I switched to a 28 I noticed how much stronger it was making me.. the same climbs don't get any more difficult, you just accept when you are in your bottom gear and have to press the pedals a bit harder

97th choice

If you want a do it all bike then go 11-32, that way if you end up doing adventure cross or one of the new gravel races that are springing up like dirty reiver, then you'll be set.

tim000

how about an ultegra 12-30 . just fitted one to my road bike .
https://www.radialcycles.co.uk/shimano- ... AmWI8P8HAQ