road vs mtb gearing

Author
Discussion

hab1966

Original Poster:

1,104 posts

218 months

Monday 9th July 2018
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Rode the Manchester to Blackpool charity bike ride yesterday alongside people on all manner of bikes.

Much kudos must go to the chap i passed riding with a prosthetic right leg, the chap on the stand up bike and a guy on a 'new' chopper stuck in one gear. Obviously lots of other heroes on the day. Conditions didn't help being hot and dry.

The bike i rode yesterday was my backup mountain bike with what i think is a 44-32-23 chainset and a 11-30 cassette. Wheels were shod with road as opposed to off-road tyres.

What i need to understand is the gearing difference between a road and a mtb. I could get a fair speed up on my bike and hold it for a while, enough to pass lots of other riders but i'd always get passed by some roadie, making it look effortless. What gearing does a standard road bike run? I appreciate with their tyres the rolling resistance is less than mine and i expect the bike weight is much less than mine also. Rider weight would also play a part!

Also not helped by watching the highlights of the TdF and seeing what speeds those guys sustain.

Finally much thanks to the charity i rode for - Wigan and Leigh Hospice, who provided two rest stops where the food and drink was free - if you had their T-shirt on. There's nothing like stop for a warm pie and a sandwich. Who needs energy gels and bananas!

Mr2Mike

20,143 posts

261 months

Monday 9th July 2018
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Road bike could have a 53 tooth chain ring, and 10 or 11 on the small end of the cassette. The rolling circumference of a 700c wheel/tyre on a road bike may be a little more than a 26" wheel MTB as well, depending on tyre sizes (though 29er MTB is larger still). As well as tyre rolling resistance, wind resistance plays a big part and the upright position of an MTB is always going to put you at a disadvantage.

Coming home from work last week (in my car) I caught up with someone on a road bike who was holding almost 40mph on the flat, and a fair bit more downhill! Most impressed, wish I was that fit.

Master Bean

3,969 posts

126 months

Monday 9th July 2018
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50 34 Chainrings and an 11-28 Cassette. That's pretty much standard on most road bikes.

anonymous-user

60 months

Monday 9th July 2018
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cadence is also significant

I see more MTBers pedalling less quickly than roadies these days

Say, ~70 cadence vs, say, ~90 can translate into a fair bit of speed

TwistingMyMelon

6,390 posts

211 months

Monday 9th July 2018
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Road bike will be much quicker, gearing is just one element, also if its on the flat weight plays less of a factor, on hills weight starts to play a big factor

It could also be he was much fitter, hence it looked effortless

MTB with road tyres are fine on the road, I used to ride one like that, when I then got my first decent road bike I was amazed at the difference.

paulrockliffe

15,960 posts

233 months

Monday 9th July 2018
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The pedalling position on a road bike is also more efficient, I'd expect that to be the dominant factor on that ride really (ignoring fitness). I think MTB to Road would be similar to Road to Time Trial in terms of the improvement in efficiency.

Gearing wouldn't really matter, unless you were in top gear at a cadence up over 100pm.