Originally Posted by
Russ Roth
Trying to figure out how to make my kid's bike better, 2019 Redline MX Mini. He's about 1" from out growing this but I'm thinking new parts could be swapped to a Jr. frame especially since complete bikes are either unavailable or really expensive but frames seem reasonably available and affordable. I'm finding carbon forks but what real advantage do they offer over stock forks, just weight? His bike is 15.5lbs as is, can't imagine it going too much lighter though with the kid weighing 80lbs any change is probably more advantageous. . Currently have Box Harmonic hubs, Bombshell expert rims, and ti spokes ordered for a lighter, faster wheelset; expecting a roughly 1100-1200g wheelset that should, more importantly, spin faster.
Hey Russ.
I wouldn't go too nuts on a Redline MX. I get what you're saying about moving parts from a mini to a junior, but forks sometimes don't make that move so well unless you put a LOT of spacers on them on the smaller size - I had a Ciari Ottomatic fork on my son's junior, but the steer tube was too short to use it on his expert. I'd wait on the fork until you're building the next bike - and if you want to move that fork on to an expert frame later, make sure you leave the steer tube as long as you dare. You might be better off just buying used and planning on selling it.
As far as carbon forks - other than the more expensive ones, (like supercross speedline or ciari piccolo) - the Answer Dagger is only a couple grams lighter than something like a Ciari Ottomatic or a Supercross SLT fork. I run a Ciari Ottomatic, and both of my boys have - the elevn steel fork is right up there too.
I don't know if you've already ordered the spokes or not, but I highly recommend double-butted steel spokes over ti - if you use ti with aluminim nipples, bad things can happen - and there isn't actually that much weight savings between double-butted and ti. The steel and aluminum nipples (which work fine together) is lighter than the titanium spokes and brass nipples. The big thing is galvanic corrosion - the aluminum nipples will corrode on the threads where it contacts the titanium. As well, you generally need high tensions with Ti because it doesn't stretch as much - you might get away with it on a kids bike that you're very careful with around moisture, but it'll eventually corrode.
The galvanic corrosion thing goes away if you use titanium nipples as well - but you're better off using butted steel spokes and aluminum nipples and putting the money into better hubs. I don't have anything against the harmonics, one of my sons uses them - but the other one has a set with the Stealth hubs, and I far prefer them (or Onyx, or Profile Elite, or Profile AC-2......) - The biggest thing in looking at hubs for BMX is the distance between engagement points - the Box Harmonic is pretty good, but Onyx and Stealth are roller bearing hubs that are virtually instant. I actually use a freewheel hub and the Box Buzz freewheel on my own bike - the freewheel solution works just fine, don't let someone tell you that you have to go cassette hub.