Cycling UK Forum

I may have more brake issues with Chopper after the new leather blocks arrive, and if I do, I would like advice about upgrades. Perhaps the leather brakes will be fine, if so, no problem. But if they are not fine - big problem!

I think I have two options:
1. Re-rim both wheels to alu. The front is 28h at present, but I have a spare 36h hub that I can use. With good blocks, I may be ok. Two rims and new spokes (perhaps) will come to £50 odd. I'll build the wheels myself.

2. Buy a mechanical disc brake system for the front. I'd still need a 36h front rim, and I'd have to manufacture a boss system for the front forks. I already have some V-brake levers, but perhaps the original one will do. After my trip, I can sell the disc brake system and get some of my money back. Just checking at SJS will get me rim plus spokes plus hub and disc equipment for about £100. Minus a few quid as a secondhand sale, there's not a great deal in it.

I like the idea of a front disc brake, it would be very powerful and inspire confidence in actually stopping. With only a 20" wheel up front, it takes some torque to stop a loaded Chopper!

Advice and thoughts please.

I had this dilemma on the Raleigh MTB, so I obtained an unused Sturmey Archer BF hub brake for the front (15 quid), and stuck my spare X-RD3 hub brake/gear in the rear. Is that an option?

Performance is outstanding, surprisingly progressive braking and immune to all-but the worse weather - though wading may be an issue

I did think of a hub brake, but am a little concerned about the 'little' wheel.
The front rim is only 12" diameter (305mm ERD) and the hub brakes are what? 4" diameter? ish? That only leaves spokes of 4" long. I'm not sure that is possible especially as there would be 36 of them.

Note: "not sure".

Crikey, I hadn't relaised the Chopper wheel was that small

The hub brakes are available in 2 sizes, 70 and 90mm (2.75 and 3.5"). I guess with flanges the smaller one would be about 3.25. I've only used hub brakes on 26" wheels, so possibly they'd be potentially heart-stopping, but no more so than the disc brakes I've used.

It's the spoke length that, as you rightly say, could be the issue.

Interesting one this.

My trike wheels are 20" with hub brakes - the 70mm hub doesn't look daft in the middle there.

Mick,
What is the actual wheel size of the front wheel? You've said 20" and 12" what would be written on the tyre? Reason I ask is that I have some small alloy rimmed wheels taken off a kiddies bike. They are on my kayak trolley at the moment, but it wouldn't be a problem in lending one to you until after the ride.

12" rim and hub brake, spokes are going to approach the rim at a funny angle. Is it 2 cross now? I am currently putting cable discs on a frame not made for it, silver soldered a bit of brass onto the front fork. Brake feels a bit sharp with aero lever! Not ready to ride yet!

Why so much time on a folly?.

A Folly?
This is a Wonderful Piece of British Engineering! ............ NOT!

The front wheel is a 12" rim, fitted with a 16x2 tyre giving a total diameter of 16".
The front rim is 305mm (12" ish) effective rim diameter. ie the diameter of where the spokes go in.

The front wheel on a 1971 Chopper is 28h 2X with an OLN of less than 100mm, but the hub is standard without locknuts. Therefore a standard hub could be made to fit.

If I need to change the rim, I need to find one at 305mm ERD with 28h,

or find any hub that matches a rim, and that will reduce itself to 90mm ish OLN.
36h or 32h doesn't matter, providing I can find a hub and rim to match.

Advice/help very much appreciated, but in the end, I need to stop/brake effectively and maintain the appearance of a Chopper.

PS.
Just taken "delivery" of an RSW16.
I know no more than you can see on this photograph:
viewtopic.php?f=15&t=33926
It seems to me that my concerns about spoke-length and a hub brake MAY be unfounded. The RSW has a front hub dynamo that is possibly the same diameter as a hub brake.

I will check lengths tomorrow, but the rim is the same as the front wheel on a Chopper and is 28h.
If a hub dynamo was available as 28h, perhaps a hub brake is too?

Yup, spokes on the dynamo side hit the rim at a funny angle!

What we really need is less words, more video. Mick F on chopper pootling down some country lane accompanied by Last of the Summer Wine esque music, how's Mrs F with the camera?.

Hi Freddie, the video idea is in hand.
I need some publicity etc ......

As for the funny angle of the spokes, the RSW16 and the Chopper have the spoke-holes "shaped" to take the funny angles.Hopefully, you can see the shape/profile.

I have an idea for later this morning.
I'll get back to this thread.

Mick,
The wheels I have are marked 16x2.125 on the tyres, which according to SB are 305's. The rims are 28H and are alloy and have a label "Fetchi". OLN of the front wheel is approx 90mm. There is no wear on the rims or tyres as far as I can see.
Mike

Thanks for your kind offer Mike.
Can I hold on for now please? I'll get back to you in a while as the wheel seems spot on. I wonder if a front alu rim would be enough?

As for what I've been doing this morning, other than thinking and experimenting, is that I've managed to fit a 36h hub on a 28h wheel! It can be done, but some of the spokes are short-ish, and some are far too long! The pattern looks ok, so It needs a bit more thinking about, and I could get a 36h disc brake system to fit onto my 28h rim.

The trouble is, the spokes would be almost impossible to gauge other than trial and error, or ordering one at a time! For the price of a 36h rim it would save the hassle.

So I think I need one each of these:
36h alu rim http://www.sjscycles.co.uk/category-Rim ... 29-163.htm
Front Disc Brake http://www.sjscycles.co.uk/product-Shim ... -20275.htm
Disc brake hub http://www.sjscycles.co.uk/product-Shim ... -20344.htm

This system will make the Chopper very safe with secure braking, and I can sell the disc brake and hub when I've finished with it. It must be possible to make a boss to clamp on the forks.

Any comments or advice?