Solomander said:I was thinking of an 11 -32 cassette, which would approximate the top
gear of my road bike but give me low climbing gears. Why is an 11
tooth ring stupid (I ask this without a trace of irony, I really don't
know)?
Stupid is probably a bit strong (sorry).
11tooth rear is prone to accelerate wear. The criticism is aimed at those
with 52T front rings and 11T rear, who need to be Superman to make use of
the gearing.
As elsewhere you've proposed a 26-36-46 chainset, then 11T at the rear gives
you a similar top-gear to 50T top and 12T rear. Personally I think much
over 100 gear inches is too high for anyone other than racing, which equates
to 50T front 13T rear, or 46T front 12T rear.
Before committing yourself on cassettes/cranks, look at the intermediate
gear spacings. On your existing bikes you'll have some favoured "cruising
along" gears. To work really well, a bike needs gears around those speeds
without massive jumps or awkward shifts (eg. swapping front rings and rear
ratio simultaneously), and with a decent chain line (eg. not "smallest rear
to smallest front"😉.
Also, check the way the bottom gear kicks in, some Shimano cassettes have a
huge jump to the bottom gear (some of the Megarange badged ones). Some
riders like it that way, others loathe it.
Quoted message said:I am currently riding a Campy double with a 13 -29 cassette and I know
that I am going need something lower if I ride with any significant
amount of weight on my bike.
An opinion I would share. But what would it be like with a triple ?
Quoted message said:As I mentioned before, I am a Campy person, but have been given to
understand that for this application (country/light touring road bike)
that Shimano wheels and cassettes will work better.
You can have any hub laced to any rim. So, its possible to have the
chunkiest ultra-distance heavy-weight off road touring rims laced onto a
Campag hub if you so wish.
Or even something weird like my partner's bike (Shimano hubs with Campag
badged rims!).
The issue is selecting an appropriate rim - the right width for the proposed
tyres, and the appropriate weight for the rider, roads and loads.
I've just been to the local bike shop to order a new wheel with a rim to
take tyres of 28 to 32mm. A slightly odd combination these days as most rims
advertised in the UK are either narrow (below 28mm tyre) or wider (32mm or
larger). But the local shop had some suitable ones (22mm wide over outside
of braking surfaces) in stock.
I understand that its possible to mix Shimano and Campag 9-speed systems
without fancy cable adaptors (at least in one direction), though the
theoretical cable pulls and rear cassette spacings suggest otherwise.
You haven't mentioned brakes (or if you did I missed it).
For what its worth, Shimano dual pivot brakes work extremely well with
Campag Ergo levers (my bike uses the combination). The Shimano brakes have a
deeper drop than Campag, giving enough room for mudguards and 28mm tyres.
There is an additional benefit of two places to increase the pad-gap to
remove a wheel (the lever on the Shimano brake caliper and the pin on the
Ergo lever), which is useful when fitting wheels with wider touring tyres.
If wanting fatter tyres than 28mm, then I think one looks at cantilever
brakes.
I've no particular preference for Campag over Shimano. I think the actual
differences are not that great once one has worked out appropriate gear
ratios. The main difference is personal preference over the Ergo/STI lever
shape and operation.
- Nigel
--
Nigel Cliffe,
Webmaster at http://www.2mm.org.uk/