32T chainring to 42T on MTB
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32T chainring to 42T on MTB
I have a mtb with 1x11 groupset. Now it's 32 chainring with 11-42 cassette.
Now, I use this bike to mountain biking but also for urban riding. In the city I feel I need a higher gear while I rarely use the lowest gears.
Do you think 42T is reasonable choice?
Thanks
Now, I use this bike to mountain biking but also for urban riding. In the city I feel I need a higher gear while I rarely use the lowest gears.
Do you think 42T is reasonable choice?
Thanks
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42/42 (1:1) low ratio is a bit tall for me for general MTB use, but I’m not you and don’t know how/where you ride. You will be the best judge of the best gearing for you.
I assume it goes without saying that you will need a longer chain.
Last edited by Kapusta; 10-20-21 at 06:43 AM.
#3
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If you can do your mountain biking in 2'nd gear, I'm guessing a 36T rear sprocket, you could replace the 32T chainring with a 38T if it will fit and still get very close to the same ratio in 1'st, and would give you a 19% boost in speed at a given cadence. That's 95 gear inches with a 27.5" tire, and sustain 35 kph @77 rpm cadence. That's pretty quick IMO for most people on a hybrid bike or a mountain bike adapted for road use.
I wouldn't suggest a 42T chainring, even if it fit. I think a 38T is good middle ground.
I wouldn't suggest a 42T chainring, even if it fit. I think a 38T is good middle ground.
Last edited by xroadcharlie; 10-20-21 at 11:33 AM.
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If you can do your mountain biking in 2'nd gear, I'm guessing a 36T rear sprocket, you could replace the 32T chainring with a 38T if it will fit and still get very close to the same ratio in 1'st, and would give you a 19% boost in speed at a given cadence. That's 95 gear inches with a 27.5" tire, and sustain 35 kph @77 rpm cadence. That's pretty quick IMO for most people on a hybrid bike or a mountain bike adapted for road use.
I wouldn't suggest a 42T chainring, even if it fit. I think a 38T is good middle ground.
I wouldn't suggest a 42T chainring, even if it fit. I think a 38T is good middle ground.
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I'd also have a look at faster rolling tyres, if you're doing a lot of urban stuff and not doing anything too difficult offroad (it doesn't sound like you are if you're wanting to increase the gearing).
I'm pretty sure my hardtail has 42T at the front with an 11-46 on the back and it's fine. I noticed a huge difference going from the stock tyres to Vittoria Barzo/Metzcals.
I'm pretty sure my hardtail has 42T at the front with an 11-46 on the back and it's fine. I noticed a huge difference going from the stock tyres to Vittoria Barzo/Metzcals.
#6
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You probably have a 37T chainring for your current 2'nd gear, not the 36 I used in the example. Run the numbers in one of those on line "gear inch calculators" to confirm the correct chainring to get close to that ratio if you wish. You might need a 37 or 36T ring instead. The calculator will show you the results and go from there.