Re: BCD and chainring compatibility

[Simon Brooke]

in message <[email protected]>, Taka <Taka> ('')
wrote:

> I have never understood why "road" rings don't work on montainbikes?

Often because of interference between the larger chainrings and the
chainstay - there physically isn't room on many mountain bikes. If there
is room, then a 'road' chainset will fit perfectly well (you're right
than in general it's not easy to put 'road' rings on 'MTB' chainsets
because of bolt pattern differences, but that's at least partly
marketing-driven rather than for technical reasons). Someone in our club
time-trials on the road an old mountain bike frame with tribars on, and
does very well.

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

;; Woz: 'All the best people in life seem to like LINUX.'
;; <URL:http://www.woz.org/woz/cresponses/response03.html>

 

[Taka]

On Sun, 07 Aug 2005 11:17:56 +0100, Simon Brooke
<[email protected]> wrote:

>in message <[email protected]>, Taka <Taka> ('')
>wrote:
>
>> I have never understood why "road" rings don't work on montainbikes?
>
>Often because of interference between the larger chainrings and the
>chainstay - there physically isn't room on many mountain bikes. If there
>is room, then a 'road' chainset will fit perfectly well (you're right
>than in general it's not easy to put 'road' rings on 'MTB' chainsets
>because of bolt pattern differences, but that's at least partly
>marketing-driven rather than for technical reasons). Someone in our club
>time-trials on the road an old mountain bike frame with tribars on, and
>does very well.

Thanks Simon,

I'm thinking of putting a compact chainset from FSA onto my MTB frame.
Hopefully it will work!

Good luck in your time trial on Tuesday!

Thanks!
Taka

 

[Simon Brooke]

in message <[email protected]>, Taka <Taka> ('')
wrote:

> On Sun, 07 Aug 2005 11:17:56 +0100, Simon Brooke
> <[email protected]> wrote:
>
>>in message <[email protected]>, Taka <Taka>
>>('') wrote:
>>
>>> I have never understood why "road" rings don't work on montainbikes?
>>
>>Often because of interference between the larger chainrings and the
>>chainstay - there physically isn't room on many mountain bikes. If
>>there is room, then a 'road' chainset will fit perfectly well (you're
>>right than in general it's not easy to put 'road' rings on 'MTB'
>>chainsets because of bolt pattern differences, but that's at least
>>partly marketing-driven rather than for technical reasons). Someone in
>>our club time-trials on the road an old mountain bike frame with
>>tribars on, and does very well.
>
> Thanks Simon,
>
> I'm thinking of putting a compact chainset from FSA onto my MTB frame.
> Hopefully it will work!

Yup. There should not be any problem with a 'compact' chainset, where the
big ring is no bigger than some MTB chainsets. Mind you you can achieve
a similar result simply by taking the granny ring off an MTB chainset -
the 'Q' measurement will be marginally greater, but for those of us who
are not serious athletes this probably doesn't matter that much.

> Good luck in your time trial on Tuesday!

Hah! We'll see...

I /should/ be able to do it, but I haven't yet.

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

[ This .sig subject to change without notice ]

 

[Dave Larrington]

Simon Brooke wrote:
> in message <[email protected]>, Taka <Taka>
> ('') wrote:
>

>> I'm thinking of putting a compact chainset from FSA onto my MTB
>> frame. Hopefully it will work!
>
> Yup. There should not be any problem with a 'compact' chainset, where
> the big ring is no bigger than some MTB chainsets. Mind you you can
> achieve a similar result simply by taking the granny ring off an MTB
> chainset - the 'Q' measurement will be marginally greater, but for
> those of us who are not serious athletes this probably doesn't matter
> that much.

The 'Q' wossname /might/ matter if the chainstays are kinked outwards to
give clearance for BFF-O tyres, though. There's not a huge amount of space
'twixt crank-end and chainstays on my run-of-the-mill Trek, anyway.

--
Dave Larrington - <http://www.legslarry.beerdrinkers.co.uk/>
Apparently Guy has now got a Brompton. I'd never have guessed.