in message <[email hidden]>,
(') said:I have a tiagra 4400 double (39-52) with a cheap shimano 68X110 square
taper BB. I already have a crank puller and BB tool.
What would anyone suggest for switching to 34-48 for minimal cost?
Mirage Chainset Compact Alloy 2006 £39.95 (Parkers). Requires 111mm
BB. Is it square taper, would 110 be close enough would my crank puller
fit it?
If you choose a new chainset with the same PCD as your existing chainset,
then if all else fails you can swap the rings from the old to the new.
Having said that, I would think a 1mm offset in chain-line would not be a
problem - the chain would be offset more than it should be in your
uppermost gear, but only very slightly; and you might want to avoid the
top two gears of your small ring, rather than just the top one.
Beware, though, that not all square tapers taper the same! I have had, in
the past a case where though both cranksets had the same taper, when fully
engaged on the taper the actual rings were in completely different places
(that's when I learned the trick of swapping the rings from the new to the
old) and there are also some makes of BB which taper more than others.
Quoted message said:STRONGLIGHT Impact Compact £58 (Spa). Needs a 107 mm BB. Would it be
worth switching to splined BB if replacing itanyway? Should I look at
something with integrated BB?
No. Splined BBs are not better, anyway, and integrated BBs offer no benefit
to ordinary cyclists. Both of these things are essentially marketing
driven, creating obsolescence in order to persuade people to junk
serviceable components and buy new. Yesterday, in the process of giving my
old road bike bike a quick once over before the winter, I stripped and
regreased the old fashioned cup-and-cone square taper bottom bracket. That
is the second time it has ever been stripped, in thirteen years and at
least 30000 miles. It was perfect, so I just cleaned out the old grease,
replaced with new, and reassembled. It will almost certainly run for
another six years. Your bottom bracket probably has several thousand miles
left in it.
Having said that, a Mirage chainset and a Mirage BB will cost less than the
Stronglight chainset, and while Stronglight are very nice, Mirage is also
perfectly nice and serviceable.
Quoted message said:I have a 31.8mm band-on tigara double FD. Is there much chance this
would still work? (it runs from ergo levers so trimming is not a
problem)
I'm pretty confident it would; your chainline should at most be 1mm further
out and that should be within the range of any decent mech. You will
probably want to lower it a bit, but since it's band on you can do this.
--
[email hidden] (Simon Brooke) http://www.jasmine.org.uk/~simon/
;; part time troll.