crank shorteners-any good?

[stewed_rabbit]

We've just bought a pashley U+2 tandem tag along to take the kids on the school run. Although it is designed for 4-7 year olds it has 160mm cranks and these seem much too long (knees up by chest at top of rotation, leg fully extended at bottom). Just wondered if anyone has tried the crank-shorteners from Thorn as they seem an ideal solution for kids who will still be growing (and we could transfer them to any future tandem)?
Would also appreciate it if anyone could describe what is meant by 'tapered squat axles' in relation to cranks as this is apparently what the shorteners fit. (My previous bike maintenance experience is limited to tyre and brake block changes)

 

[mickle]

Square taper, It' sa typo. Crank shorteners are good but you could probably purchase a shorter chainset for less. They tend to be used on the back of tandems running decent quality multi ring chainsets. They also, of course, increase the distance from pedal to pedal quite a lot (Q factor), which is considered a bad thing.

If you have a spare aluminum crankset it's possible to get them cut down and new pedal threads tapped if there is enough material in them. Highpath Engineering for example.

 

[stewed_rabbit]

Cheers mickle, good to have some options. Looks like it'll be a trip to the nearest recommended LBS.

 

[mickle]

Aye, nae bother.