How much do you want to spend? As already mentioned the easiest and quickest is to get a Campagnolo
13-29 10 speed cassette and new longer chain and put it on. Not sure how cheap or expensive 10 speed
13-29 cassettes are. $60? $80? Chain will be about $30 give or take. But a 39x29 low gear may not be
as low as you need.
If you need lower then you have to get a triple front crankset. A 110 bcd double will get you a bit
lower but not enough to matter. Get a triple and get real low gears. Can't think of a more
unenjoyable way to spend a trip in France riding up mountains with too high of gears.
Excel Sports sells a Centaur triple kit for $225 I believe. Crank, front and rear derailleurs, and
bottom bracket. I have this setup and used it on a Rocky Mountain biking week. The 30 tooth small
front ring matched with my 28 large rear cog was just barely low enough. If you go the triple route,
buy a cheap 24 and/or 26 74 mm bcd chainring from Nashbar for $5-10. Or about $20 from Excel. A 24
or 26 front inner chainring matched to your existing 25 large rear cog should get you low enough to
enjoy the ride.
Your existing low gear of 39x25 is 41 gear inches. (Front chainring teeth divided by rear cog teeth
times wheel diameter of 26.5 inches.) A 34x25 comination is 36 gear inches. You have to buy a new
crankset to get this. A 39x29 combo is 36 gear inches. You have to buy a new rear cassette and chain
to get this. Probably cheaper than the new compact crankset, unless you can find a really cheap old,
used, NOS, compact crankset somewhere. New compact cranksets are in style now so they are expensive.
But a triple gives you the lowest and most useful gears. A 30x25 combo gives you 32 gear inches. You
have to buy a new triple crankset, bottom bracket, derailleurs for this, $225. And with a 26 inner
chainring, $5-10 from Nashbar, you get a 26x25 28 gear inch low gear.
[email protected] (Colin Marshall) wrote in message
news:<
[email protected]>...
> Hi,
>
> I'm going to the tdf this year and hope to climb some of the mountains while I'm there.
>
> I have a 2002 10 speed Campag Chorus double setup, with a 53/39 and
> 12/25. I realise this is not going to be low enough for me to get up, unless I become superman
> soon.
>
> What is the lowest I can get for my existing setup. I know there is a
> 13/26 but what about the front? Something like a 33 or 35 would be nice, but is it possible?
>
> TIA
>
> Colin