Speed MTB v Road Bike

Cat555 <[email hidden]> wrote:
: Hi guys I am new to the cycling scene, and I want to buy a new bike.

: My question is, what is the diference with the gearing on MTB's as compared
: to a Road Bike.

It's literally a matter of counting sprocket teeth. It's common on
current road bikes to have 39/53 up front with 12-23 at the rear. MTBs
have 22/32/42 and 11-28. The lowest gear for road is 39:23 while MTB goes
22:28. The high ratios are 53:12 for road and 42:11 for MTB. The numbers
may be a bit meaningless but believe that MTBs are overall geared lower.
That is, they are great for getting up steep hills but are not geared for
higher speeds. The smaller rim diameter of MTBs doesn't figure because the
rolling diameter of the tyre is effectively the same as a road bike.

Road bikes are great for going fast on roads with their higher gearing
while MTBs are excellent for bombing down dirt tracks, etc.

Hope this helps, cheerz,
Lynzz

Lindsay Rowlands said:

Cat555 <[email hidden]> wrote:
: Hi guys I am new to the cycling scene, and I want to buy a new bike.

: My question is, what is the diference with the gearing on MTB's as compared
: to a Road Bike.

It's literally a matter of counting sprocket teeth. It's common on
current road bikes to have 39/53 up front with 12-23 at the rear. MTBs
have 22/32/42 and 11-28. The lowest gear for road is 39:23 while MTB goes
22:28. The high ratios are 53:12 for road and 42:11 for MTB. The numbers
may be a bit meaningless but believe that MTBs are overall geared lower.
That is, they are great for getting up steep hills but are not geared for
higher speeds. The smaller rim diameter of MTBs doesn't figure because the
rolling diameter of the tyre is effectively the same as a road bike.

Road bikes are great for going fast on roads with their higher gearing
while MTBs are excellent for bombing down dirt tracks, etc.

Hope this helps, cheerz,
Lynzz

Also, the rolling resistance of an MTB tyre, being fatter, lower
pressure, and often knobblier, is more than that of a road bike. This
doesn't affect gearing per se, but it does affect the amount of
pedalling effort, which is maybe what your question was driving at anyway.

(maybe this too would have been better asked on rec.bicycles.tech)

&roo

Lindsay Rowland said:

Cat555 <[email hidden]> wrote:
: Hi guys I am new to the cycling scene, and I want to buy a new bike.
: My question is, what is the diference with the gearing on MTB's as
: compared to a Road Bike.
It's literally a matter of counting sprocket teeth. It's common on
current road bikes to have 39/53 up front with 12-23 at the rear.
MTBs have 22/32/42 and 11-28. The lowest gear for road is 39:23
while MTB goes
22:28. The high ratios are 53:12 for road and 42:11 for MTB. The numbers
may be a bit meaningless but believe that MTBs are overall geared
lower. That is, they are great for getting up steep hills but are
not geared for higher speeds. The smaller rim diameter of MTBs
doesn't figure because the rolling diameter of the tyre is
effectively the same as a road bike.
Road bikes are great for going fast on roads with their higher gearing
while MTBs are excellent for bombing down dirt tracks, etc.
Hope this helps, cheerz, Lynzz

Let's not forget that a road bike can be geared to help with hill climbes. Say if a triple crank is used up front and a 12-27 cassette in the back, then the lightest ratio will drop from 39:23 (1:1.69) to 30:27 (1:1.11). Rear sprockets on MTBs are up to 30-34 teeth on the bail-out ring these days. So the figure on MTB can be as low as 22:34 (0.65:1). Still a big difference, isn't it?

--