Kddie Cranks - Gearing

[dvines]

Hi

I am just setting up a tandem with Kiddie-Cranks for my 8yo nephew.

Does anyone have any experience of how these should be geared - same as stoker or geared down so they are pedaling faster than you ? and if so by hiw much ?? I think the cranks have a 40T ring on them currently down to a 40T ring at the cross-over drive.

Is this likely to cause a problem if you are not pedalling at the same speed/in phase ?

As purchased it will e the same gearing... so I was going to try this first.

[Brucey]

the normal arrangement is to have a 1:1 drive onto the main transmission, i.e. have the kiddie cranks going at the same speed as the others. I think the idea is that little legs go in little circles at the same speed as big legs go round big circles...

cheers

[ChrisButch]

I was fortunate enough to begin my cycling career on these. Just checked in the old family scrapbook. In the minute Box Brownie photo of me and my dad on the 1930s Evans tandem, I can just about see behind my fat little legs that the kiddiecrank chainring was indeed the same size as the linked drive chainrings below it.

[gaz]

.

[JEJV]

In phase.

But it's the Crank Length you want to think about. 8YO's come in a variety of sizes, but 150mm cranks are probably in the ballpark.

A colleague of mine got Highpath to drill an extra set of holes in the cranks, so they can be used at 150mm or 170mm. I think 20mm is the minimum hole separation.

That way grown-ups can still ride it. (Might need a longer seatpost).