"Road Cassette" on MTB hub

(Matt Peeler) said:

Is there any difference in a so called "Road Cassette" such as a HG70 8sp and and a ATB cassette. I
am wanting to narrow my rear cluster for more street riding and I was going to use na HG70 12-21 to
put on a new rear wheel I was going to buy with shimano hub.

Is it just a classification for sales purposes mostly?

Thanks

Matt p

The mounting is the same and a 'road' cassette will fit on your 'mtb' hub.

The different names seem to be based on the typical gearing for road bikes versus typical gearing
for mountain bikes. Road gearing emphasizes small steps between gears and not much concern about
low gears for hills. Even a triple on a road bike will give a much higher low gear than mountain
bike gearing.

If you go to a 12 as the smallest rear cog, you should look into a larger chainring. A 42 or 44 with
a 12 is easy to spin out.

There is a nice online gear calculator by Sheldon Brown here:

sheldonbrown.comgearsOpen ↗

You can play with different combos and compare it to what you are actually using on your
bike already.

A long cage rear derailleur for 28-32 or more might not shift a 21 as crisply as a shorter cage
'road' derailleur. You'll need to adjust the position of the jockey pulley to get it closer to the
cog. If you like the tighter gearing but find the shifting is not quite as smooth, think about using
a shorter cage derailleur.

In article said:

Is there any difference in a so called "Road Cassette" such as a HG70 8sp and and a ATB cassette.
I am wanting to narrow my rear cluster for more street riding and I was going to use na HG70 12-21
to put on a new rear wheel I was going to buy with shimano hub.

Is it just a classification for sales purposes mostly?

The clusters are perfectly interchangeable*, but the gear choices are suited to the needs of each
bike. Current MTBs run "compact" drive systems with smaller front rings, for ground clearance and
the lower speeds that MTBs are used at. As a result, these small front rings are paired with a
wide-range cluster that typically goes something like 11-32, so that the small cog is small enough
to get you to a decent top speed, and a low gear that allows you to twiddle up very steep climbs.

Note that a mountain cassette can have both lower lows and higher high gears than a road cassette,
though 11t small rings are available on road clusters. The upshot is that you will not be able to go
faster with a road cassette, but the gear differentials will be conveniently smaller, and you can
surrender some useless-on-the-road low ratios for gears you might use.

If it was me, and the cassette still had life in it, I would consider a larger big ring for the road
rather than a different cassette. OTOH, cheap cassettes can cost less than moderately priced front
rings, so you might be making the better choice if you can get the gearing you want.

*Rear derailleur capacity may be an issue, but typically only if you try to use a really wide
mountain cluster with a short-cage road derailleur.
--
Ryan Cousineau, [email hidden] sfu.ca~rcousineOpen ↗ President, Fabrizio Mazzoleni Fan Club

Ryan Cousineau <[email hidden]> wrote in news:rcousine-12AC61.22593728082003 @morgoth.sfu.ca:

Quoted message said:

The clusters are perfectly interchangeable

One incompatibility is that 11 tooth MTB cogs are not designed to work on Shimano road freehubs. See
sheldonbrown.comk7.htmlOpen ↗ for some workarounds.

Ryan Cousineau said:

Quoted message said:

The clusters are perfectly interchangeable

Ken said:

One incompatibility is that 11 tooth MTB cogs are not designed to work on Shimano road freehubs.
See sheldonbrown.comk7.htmlOpen ↗ for some workarounds.

Actually, this doesn't have anything to do with "road-ness" vs "mtb-ness" which is actually more of
a marketing distinction than a functional one.

It is more related to the _age_ of the Freehub. Older designs were not compatible with 11s, newer
ones are. The article referred to above goes into more detail on this.

Sheldon "Hyperdrive C" Brown +----------------------------------------------+
| My mind is aglow with whirling, transient | nodes of thought careening through a cosmic | vapor
| of invention! --Mel Brooks |
+----------------------------------------------+ Harris Cyclery, West Newton, Massachusetts Phone
617-244-9772 FAX 617-244-1041 harriscyclery.comharriscyclery.comOpen ↗ Hard-to-find parts shipped Worldwide
captainbike.comcaptainbike.comOpen ↗ sheldonbrown.comsheldonbrown.comOpen ↗

Matt Peeler said:

Is there any difference in a so called "Road Cassette" such as a HG70 8sp and and a ATB cassette.
I am wanting to narrow my rear cluster for more street riding and I was going to use na HG70 12-21
to put on a new rear wheel I was going to buy with shimano hub.

Is it just a classification for sales purposes mostly?

The MTB rear derailleur will have a higher slant angle than road rear derailleurs. This will likely
degrade shifting on the 17-19-21 cogs of the 12-21. Other than that, it doesn't matter.

gwhite-<< The MTB rear derailleur will have a higher slant angle than road rear derailleurs. This
will likely degrade shifting on the 17-19-21 cogs of the 12-21. >><BR><BR>

????

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 vecchios.comvecchios.comOpen ↗ "Ruote convenzionali costruite eccezionalmente bene"

"Matt Peeler" <[email hidden]> a écrit dans le message de
"]news:[email hidden]...

Quoted message said:

Is there any difference in a so called "Road Cassette" such as a HG70 8sp and and a ATB cassette.
I am wanting to narrow my rear cluster for more street riding and I was going to use na HG70 12-21
to put on a new rear wheel I was going to buy with shimano hub.

Is it just a classification for sales purposes mostly?

Mostly.

Actually, if you already have a cassette, you could build yourself a hybrid one. I have a custom
cassette with 12-14-15-16-17-19-21-25-32, made from a 12-25 and a 11-32 (all HG-70 or 105 quality).
Just remove the tiny bolts or cut the rivets that hold the cogs together; mix and match.

Regards,

Michel Gagnon

Qui si parla Campagnolo said:

gwhite-<< The MTB rear derailleur will have a higher slant angle than road rear derailleurs. This
will likely degrade shifting on the 17-19-21 cogs of the 12-21. >><BR><BR>

????

I mean exactly what I wrote. If you have a _specific_ question, then ask it.

Qui si parla Campagnolo <[email hidden]> wrote:
: gwhite-<< The MTB rear derailleur will have a higher slant angle than road rear derailleurs. This
: will likely degrade shifting on the 17-19-21 cogs of the 12-21. >><BR><BR>

: ????

Peter,

I think he means corncob versus mega-range.

--------------------------------
Bob Masse' [email hidden]
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