I'm building a decent MTB for my daughter using a Scott Spark 20 junior as the starting point.
I'm struggling to find decent 20" rims that are wide enough to take a decent tyre which don't have 36 drillings. 36h rims seem overkill for the intended use and all of my bikes have less (mix of Mavic and Roval wheels with 24h and 28h).
I might have tracked down some decent 32h rims and 32 hubs seem pretty common.
As I'd like to reuse / carry forward as much kit from the build into future builds as possible, I'd like to know if 32h hubs are pretty common in wheel builds for general XC / trail use or if most folks go for 28h rims and hubs.
Any thoughts?
32 is 'standard'.
only got the odd 36h left everything else is 32 but through natural brutality I've got down to 28/29 on occasions.
32 is standard for normal (ie none "factory") wheels. Kids could probably get away with 24 or 28 if they were well built (i assume the 36h stuff is either left overs from BMX thrash machines or for cheap crap wheel builds)
28 is next most available normal build but may be a bit trickier to get rims/hubs for. You could look at doing funky spoking with mismatched hubs/rims but that might end up being a right PITA.
Thanks for the input - helpful.
As suggested above, most of the 20" rims are designed for BMX and therefore they tend to be built up into quite strong wheels. Even firms like Alienation who list drilling options, don't sell them anymore - it's all 36h on their regular rims.
I could get Velocity rims in 28h I think but they are a narrower rim and might be less easy to sell on if 28h hubs are less common.
The 2 wheel builders I've talked to won't touch rims and hubs with different numbers of holes which backs up the suggestion they are a PITA to build!
4 spokes isn't going to make any noticeable difference to the weight. Selecting a lighter inner tube would make more of a change. I wouldn't worry about it, just go for a reasonably light 32h rim.
Essentially I think you're over thinking it!
I'm struggling to find decent 20" rims that are wide enough to take a decent tyre
You're over thinking the width of the rims too - you're not gonna have issues with 20" kids bike tyres coming up square on narrow rims.
Thanks for the comments guys. I've ordered some 32h rims so I'll see how I get on!
Light weight inner tubes turned up from the States yesterday (via a friend at work).
