chainset question UK

Steve Watkin said:

I want a new chainset for my 'bent but need a triple that will take a
20 tooth small ring and have 165 or 170mm cranks. Any ideas what
will do?

Off-the shelf, don't know. Lots of options at 22T based around the 4-arm
MTB standard, and should be available in 170 from somebody. Can you not get
the extra couple of teeth back with the ratio at the rear sprocket ?

Total bespoke option, might cost you £150+: TA. Wade through the official
site to find the specs for cranks (there is an English option :-) ).
http://www.specialites-ta.com/

Its not particularly clearly presented until you get to this table.
http://www.specialites-ta.com/produits/crank/crankdetails1_gb.htm

From the table, Carmina and Vega cranks with Compact range spiders (94 &
58mm PCD). You get any crank length in 2.5mm increments for Carmina.

Refer then to the VVT (aka Mountain bike) sprockets section and you get to
this table:
http://www.specialites-ta.com/produits/plateaux/infos_plateaux.htm
Which says that the 94/58 spider (Compact) goes down to 20T (and you get a
choice of silver or black!).

Same table says that the middle option for that spider is 32 to 40 (in steps
of 2), and outer is 42 to 50.

So, putting that lot together, Carmina Crank, TA bottom bracket (unless
someone can confirm that the TA taper is exactly the same as other makers),
Compact triple spider, Compact rings.

UK sources; Chicken and Sons are the importers; many (most?) decent bike
shops will have access to them. Spa Cycles in Harrogate might be your best
mail order option.

This page has the cranks and spiders (though not that well described, the 94
& 58 is described as "94"😉
http://www.chickencycles.co.uk/products/chains/pg_chainsets.html

This page has the rings:
http://www.chickencycles.co.uk/products/chainrings/index.html

- Nigel

--
Nigel Cliffe,
Webmaster at http://www.2mm.org.uk/

Steve Watkin said:

I want a new chainset for my 'bent but need a triple that will take a 20
tooth small ring and have 165 or 170mm cranks. Any ideas what will do?

Middleburn will do it http://www.middleburn.co.uk/cranks_rs7.php

Kinky Cowboy*

*Batteries not included
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