On Friday, April 12, 2019 at 3:27:51 PM UTC+1, db wrote:
My son is set on getting a belt drive for the bike he
is building. What is good about them? You have to have
the exact length for your bike, and if it breaks, it
is very expensive to replace.

So, why?

--
Dieter Britz

Theoretically the belt is cleaner. In fact, it is only easier to clean by brushing road dust off it. Until you do brush it down, it transfers dirt to your trousers.

The solution to cleanliness superior to what the belt offers is Hebie's Chainglider, which encloses the entire chain, chainring and sprocket. It is so impervious incoming or outgoing gunk, I run my chains inside one on the factory lube for their entire life, so there's no cleaning required. For a report of my original feasibility study see:
http://thorncyclesforum.co.uk/index....42349#msg42349
and here you can read passim about the experience of the many other knowledgeable tourers who followed me into the Chainglider:
http://thorncyclesforum.co.uk/index....42349#msg42349

Andre Jute
Noblesse oblige