My sons an absolute lunatic on his balance bike, bikes a 12″ hoy from Evans.
He’s ready to learn to use brakes, and also needs them to slow him down!
My first thought was to machine some v brake mounts like these..

Fit some tektro mini v brakes and junior lever..

Looking at his bike there’s a hole on a cross member between the chain stays.
I’m assuming that I can fit a Caliper style brake like this..

Does anyone know what the distance needs to be from the pivot bolt to the caliper?
I’ve measured from the mounting hole on the frame to the centre of the rim, 85mm (rear wheel.)

Can you get a 85mm drop?

Should have just bought a Ridgeback Scoot in the first place. They have a brake, and are £10 cheaper! 🙂

That’s as much use as a chocolate teapot

My effort:

Doof door

That’s exactly what I’ve got in mind..
Which levers did you use, and how are they for little hands?
I’ve just been drawing up some mounts in Inventor.

It’s a Tektro lever with the reach adjustment wound in quite far. Seems to work ok.
Tektro do a mini bmx lever too (as you saw on that mtbr thread) that you can use with mini-v’s.
Let me know if you want the cad file for the mounts.

PP, if there was a ‘like’ button, I’d have clicked it! 🙂

Doofdoof

Only just seen your post on mtbr.
I’ve just measured the distance between the frame where the mounts would sit.
Its 66mm, looking at the hub in your pic, I’m guessing that’s narrower than the frame your mounts are on?

If not then yes please send me the cad file..email in profile.
8)

My frame is a 12″ Hotrock with 110mm rear hub spacing (replaced the horrible coaster hub with a modified track hub) . I’ve a couple of designs I’ll send through to you. You may be able to tweak them if they won’t work as-is.

I’ve just fitted a rear brake to the BB I made for my daughter. I used an XT lever but made a spacer that sits inside the barrel adjuster to limit the lever movement. I can reduce the distance to the bars to about 15mm which fits her hands perfectly. By altering the length of the spacer I can increase/reduce the distance.
Some pics here: http://singletrackworld.com/forum/topic/homemade-cncd-balance-bike-much-progress/page/5

Stevied
I came across your thread yesterday.
That’s some brilliant work you’ve done there, which I had access to all the machinery you do.
I machine everything manually on a little sieg X2..

Thanks for the info on added a spacer.. I’ll see if I can do that with the tektro 325a levers I’ve ordered to go with the mini V’s.

Do you know if brake boss bolts are all the same thread and length? Guessing M6?

Cheers GD. Good work doing it manually, I stay as far away from the manuals as I can these days..
The XT lever adjuster barrel is 6.4mm diameter so just used a bit of 1/4″ tube and, starting long, just cut it down until I had the right reach.
I think the bosses are M6 but I’m using M8’s as it made the adaptors easier to make.

Did you make your own bosses?

I was just going to be lazy and get some off eBay..

I had to as the rear stays are not round (or square) so none of the commercially available ones would work.
On this photo it’s the silver bit under the brake.

Also had to make a clamping piece that sits inside the relief on the underside of the stays

I used an M8 bolt as this goes through the brake, mount, rear stay and screws into the piece that fits into the slot on the underside

Stevied: can I ask you about the brake lever spacer? I have some XT levers like that I’d like to “shrink” for my 4yo and the reach adjuster just doesn’t go far enough. Is it just a tube to fit against the inside end of the barrel adjuster, which the “cable end bit” then butts up against?

Cheers!

PS… both ours went brakeless on the balance bike. No major accidents but a LOT of ruined shoes 😉

@jonathon:
I used a piece of 1/4″ diameter tube (about 5mm internal diameter) that I cut to about 35mm long. This then goes inside the threaded part of the barrel adjuster and prevents the lever going fully back as it sits against the cage that holds the cable. You can alter the reach by screwing out the adjuster or cutting the insert tube shorter..

Cheers – that’s what I imagined you meant. I’ll have a play. It’s on a Beinn20 with 8spd gripshift (awful) and I’ve got old XT STI Rapidfire levers which might let me kill both the shifting and braking issues with one stone 🙂

Doofdoof
Where did you get ur brake bosses from?

Can you confirm if there M10x1.25 please? Need to get a tap if they are. I’ve got every tap apart from one of these!

They were off a 2003 fox fork, M8 I believe. ebay or Toroonto cycles have them. Or someone here will have some no doubt.

Milled the clamps for his brake bosses..and fitted the tektro mini V Brakes.
Along with a tektro Lever..
Little man can reach the levers with just the reach adjustment screw wound in.

His bike is waiting for him in the lounge, when he gets up Mrs will tell him Daddy has fitted his “brakers” as he calls them.

Nice job!

Rear brake is good but not foolproof. My son managed a great fish tailing skid that ended up in a heap on the ground at the weekend. Needed to weight the bike by sitting more in the seat but was also trying to stand/stop at the same time.

May have to loosen the brake pad adjustmentup if his grip has gotten too strong and consistently locking back wheel.

Doofdoof..
Thanks, looking forward to his skids tomorrow 😀

Get a new tyre in stock 🙂

Nice job GD 🙂

Cheers Stevied..