Road Tyre Size

[Tj]

I have 1.95 Knobblies on my MTB wheels and want to change
them to Road tyres.

Rim's appear to be 1.3" wide are there any rules on
tyre width I have a choice of 1.3 or 1.6 and would
prefer the 1.6's

I use this bike for the short 5 mile commute to the office
across epsom downs and find that when descending I am unable
to propel the bike as it coasts faster than the gearing
allows me to pedal and despite some pretty big climbs I
always leave the big cog on the front all the time and just
use the 4 outer (smallest) sprockets on the rear.

I'd like to know what to upgrade the gearing to so that
I have a better spread of much more useable gears do I
just change the rear cassette, the front or both and to
what ??????

Thanks

TJ

[Peter Clinch]

TJ wrote:

> Rim's appear to be 1.3" wide are there any rules on
> tyre width I have a choice of 1.3 or 1.6 and would
> prefer the 1.6's

They ought to fit on, so get the ones you prefer.

> I use this bike for the short 5 mile commute to the
> office across epsom downs and find that when descending
> I am unable to propel the bike as it coasts faster than
> the gearing allows me to pedal and despite some pretty
> big climbs I always leave the big cog on the front all
> the time and just use the 4 outer (smallest) sprockets
> on the rear.

If you're doing big climbs on the big wheel and only the wee
cogs at the back it's entirely possible you're being a bit
of a Masher. While MTBs' smallest gears are for really daft
things the middle ring and bigger cogs at the back are more
typically useful for big climbs on decent surfaces at usual
road gradients. You might find that upping your cadence is a
good idea as it's generally better for your knees and if you
do longer rides it generally gives you rather more
endurance.

> I'd like to know what to upgrade the gearing to so that
> I have a better spread of much more useable gears do I
> just change the rear cassette, the front or both and to
> what ??????

Cadence increases aside, you can do either or both of the
above to fiddle the gearing. You'll generally need special
tools to replace either so usually easiest to leave it with
a bike shop and have them do the work.

My tourer has a good spread of gears, from walking pace up
to practically impossible to spin out. Big ring at the front
is 52 tooth, wee one is a 30, at the back it's 11-34. Your
mileage may vary, but that does just about anything I want.

Pete.
--
Peter Clinch Medical Physics IT Officer Tel 44 1382 660111
ext. 33637 Univ. of Dundee, Ninewells Hospital Fax 44 1382
640177 Dundee DD1 9SY Scotland UK net
p.j.clinch@dundee.ac.uk http://www.dundee.ac.uk/~pjclinch/

[Mark Tranchant]

TJ wrote:

> I use this bike for the short 5 mile commute to the
> office across epsom downs and find that when descending
> I am unable to propel the bike as it coasts faster than
> the gearing allows me to pedal and despite some pretty
> big climbs I always leave the big cog on the front all
> the time and just use the 4 outer (smallest) sprockets
> on the rear.

Sounds like you need to pedal faster and push less - use
the middle ring (assuming a triple). Your knees with thank
you later...

> I'd like to know what to upgrade the gearing to so that
> I have a better spread of much more useable gears do I
> just change the rear cassette, the front or both and to
> what ??????

http://tranchant.plus.com/cycling/gears/

--
Mark.

[David Martin]

On 10/6/04 4:12 pm, in article US_xc.13288$NK4.1921951@stones.force9.net,
"Mark Tranchant" <mark@tranchant.plus.com> wrote:

> TJ wrote:
>
>> I use this bike for the short 5 mile commute to the
>> office across epsom downs and find that when descending
>> I am unable to propel the bike as it coasts faster than
>> the gearing allows me to pedal and despite some pretty
>> big climbs I always leave the big cog on the front all
>> the time and just use the 4 outer (smallest) sprockets
>> on the rear.
>

That brings tears to the eyes just thinking about it. You
must really hate your knees. Practice spinning in low
gears. Honestly.

I used to ride around there and the climbs are quite steep.

..d

[Davek]

TJ:
> I'd like to know what to upgrade the gearing to so that
> I have a better spread of much more useable gears do I
> just change the rear cassette, the front or both and to
> what ??????

How many teeth are there on your big chainring? And what
sprockets do you have on your cassette?

I've been noticing recently that a lot of hybrid/mountain
bikes people are riding on the road have what look like very
small "big" chainrings - small enough in fact that spinning
out on the flat is a likely scenario. If yours is one of
these then no wonder you can't pedal fast enough on the
descents - increasing your cadence *may* help, as others
have suggested, but then again it may not. Unless you can
get your cadence up near the 200rpm mark.

The solution in this case would be to upgrade your chainset
to one more suitable for road riding. Or get a proper road
bike and save the mountain bike for going up mountains.

d.

[Zog The Undenia]

TJ wrote:

> I have 1.95 Knobblies on my MTB wheels and want to change
> them to Road tyres.
>
> Rim's appear to be 1.3" wide are there any rules on
> tyre width I have a choice of 1.3 or 1.6 and would
> prefer the 1.6's

Definitely the 1.6" ones. They will have a better rounded
profile on your rims, and the bike will corner more easily
- plus they're unlikely to blow off if you put a lot of
air in them.