Got half an hour today to put a chain on it and roughly set up the gears and brakes. Took it out on a ride with my daughter. The build has ended up pretty light and the Kingpin is very agile and fun to ride. It also appears comfy. As my ride partner was an eight year old girl I didn't exactly get to push it, but initial impressions are positive.
Only one issue really and that's a lack of clearance for the chain, which rubs against the inside of the seat stay in top gear. Plan A is to swap the chainring to the inside of the crank arms and hope that a tweak to the chainline is enough to stop it fouling. If that doesn't work then plan B would be to re-space the rear axle so that there's a bit more room on the drive side. Of course I'd need to re-dish the the wheel too. But one way or another I should be able to make it work.
Other thoughts...The front brake works brilliantly, rear is pretty hopeless. On the plus side I think that proves that the levers are not V-brake only. I guess the rear is partly "what it is" - a large, flexy caliper and a long cable run. But I'm hoping that part of it is the rubbish original pads - rock hard, and due to their shape making minimal contact with the rim. I might swap them for some better V-brake type pads.
Gearing is currently a bit short for my taste and the local terrain, made worse by the chain rub which means I avoid using top gear. It would climb just about any hill as set-up, but ideally I'd probably have a bigger chainring on the front for a good spread of ratios. It can be had up to a decent speed by spinning the pedals, but given the small wheels you basically want as big as possible at the front and as small as possible at the back...
xerxes":3uvixhuf said:
How do you find the pedal ground clearance? I remember reading somewhere that in addition to the extra brake reach it could be problem when changing to smaller BMX size wheels.
Well, it's not been an issue so far. Pedals are a bit close to the ground by comparison with an MTB but for pootling around it's not likely to be an issue. The plus is a low standover height which combined with the step-through frame make it a very easy thing to use.
sherlylock":3uvixhuf said:
Yeah.....lovin' this. After riding my std Twenty in a couple of times to work last week I can see that a modified one is going to be a huge amount of fun to ride.
Looking at saddle/stem heights I take it you're fairly tall? (at 6'2" I can't get the std saddle high enough on the Twenty!)
I'm just under 6'. As set-up in the previous pictures the saddle was a bit high, although thanks to the low standover height it was perfectly ridable. Fits about right in the picture above, bars are on the high side but give a nice upright position for town riding. If I was on a longer trip I'd probably adjust the stem to get the bars down and forward. Quite doable.
Incidentally the bars were super cheap Chinese jobs off ebay and I'm impressed. They're light, stiff and appear well made.
https://www.ebay.co.uk/itm/302845180293
