Shortest insertion dropper post + short cranks

My sub-5ft son is riding an XS Trek with a Brand-X 125 dropper that fits fine. He doesn't need the full length, just stops the seat at the point where it works for him.

I think the answer to shortest insertion post / shortest stack height on a post questions is normally the Oneup post. They have loads of useful dimensions etc here: OneUp components document

Bonus with them is that you can shim them down another 20mm if it's still too high when it's inserted.

Edit - corrected the link

For short cranks i would look at SJS, and find some square taper cranks and fit a square taper BB.

Ian

For short cranks you'll need to look at kids stuff. There aren't really many cheap options and most of the cheaper bits are square taper with 4 bolt rings holes (if your lucky). There are some short external BB options but they are pricey. Another option is cheap Chinese site sourced cranks though some of the reviews about variable quality put me off.

Though this site suggests the cheap goldix through axle cranks are good and actually made by Samox.

https://thebikedads.com/kids-cranks/

No idea if it's possible, but could you use some 150mm Bosch ebike cranks with an Isis bb?

I'm guessing lack of chainring interface may be an issue

Does anyone know if the one up components dropper is compatable with the Shimano dropper lever?

Cranks: Spa sell weeny cranks.
Dropper: you can get Brand-X Cycloross droppers of 60mm - I am buying mrs_oab one.

I am trying to adapt a small orbea occom for my girlfriend, who is only 5ft tall, and the bike is still a bit too big

I am wondering if you need to reconsider the frame size....? A quick squiz at the Orbea size guide suggests that a small is not really that small.

That is 19mm taller bb, 38mm taller seat tube, 28mm longer TT/50mm longer reach and 40mm higher stack than mrs_oab's current bike - and she is 5'/150cm.

That leaves you effectively 50-60mm less room between BB and saddle to play with for a dropper than mrs_oab has...?

Compare:
Current bike:

Last two bikes:

Orbea in small:

Does anyone know if the one up components dropper is compatable with the Shimano dropper lever?

Yes, it is. That's what's on my son's bike. It's the cheaper option of the two (MT-500, I think) but I don't think they are any real differences between them.

The Shimano lever clamps onto the cable (rather than having the nipple in it) so it should be compatible with any dropper. Certainly the cable pull etc. seems to work well with the OneUp post.

ok thanks

I have ordered a one up components dropper and a set of those goldix cranks.

That Giant looks like it’s been left in the sun a bit too long and melted.

True.
But it fits well.