Changing the gearing on an Avanti Metro 8c

[MattyK]

Triple: http://www.bike24.com/1.php?content=8;n ... pgc=69:235" onclick="window.open(this.href);return false;

Search for trials cranks:
http://www.onza.com/components/drivetra ... nkset.html" onclick="window.open(this.href);return false;
http://www.tartybikes.co.uk/cranksets/o ... 10079.html" onclick="window.open(this.href);return false;
24T is a common trials size. With a (common) 20T sprocket that would be basically the same ratio as 26-22.

You will probably lose your chain guard. If you want to keep it, you could cut your existing chainring and adapt a custom ring onto the 3 holes for that small ring.

[Biffidus]

Hrm that could work.

What's the bet my local charges $70+ for those cranks

[MattyK]

UK shipping is usually pretty good.

Further thoughts though:
http://www.tartybikes.co.uk/cranksets/o ... 10079.html" onclick="window.open(this.href);return false;
Looking at the inside of those cranks, they look like a MTB triple with a bashring outer, no middle and the 24T on the inner position. (Manufacturer stamps says Lasco.)
This would kind of make sense because the Tarty bikes site suggests that trials guys typically use a very long BB (~128mm), which I assume would be necessary to get the chainline right when using just the inner ring -see the Questions for that product: http://www.tartybikes.co.uk/cranksets/o ... tions#q106" onclick="window.open(this.href);return false;

[Biffidus]

Very cool looking but $80 delivered.

I think I'll watch ebay for a cheap triple crankset with removable chain rings.

[Biffidus]

Update: Just in case others find this thread while trying to do something similar...

A friend pointed me to the Dutch Bike Bits website where I found a set of 33T square taper Shimano Cranks to replace the no-brand 38T (shipping was a little high but I found the same thing on Ebay for $44 delivered). A 24T rear sprocket will get me the rest of the way there.

[MattyK]

16 euro here: http://www.rosebikes.com/article/shiman ... aid:287959" onclick="window.open(this.href);return false;

Have you got the recommended BB for it too? (118mm)

[Biffidus]

I'm using the original bottom bracket. Everything seems to line up.

Edit: That's 16 Euros plus at least 9 for shipping. Only about $10 difference at most and I got it in 2 days!