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A can of worms

June 23, 2011

When I started out refurbishing this bike I thought it would be a simple case of removing some parts and connecting the gaps. How wrong I was. So many rebuild or conversion sites recommend that you do all sorts of extra repairs in parallel with your project. Naively I dismissed this and got on with focusing on just the gears on the rear wheel. However, as soon as I had started to dismantle the bike and do a bit of cleaning, I discovered a few things on the bike that needed fiddling with – a tightening here, an adjustment there. Of course, being the tinkerer that I am, I did just that, I messed with those parts to see if I could get them to work better. Instead I found out that these parts didn’t need just adjusting; many of them needed replacing altogether. A can of worms was open.

Problem 1 – the brakes

I thought these worked reasonably well on the bike before I started out on this conversion. Yes the front one squeaked a little, but they still stopped the bike.

Weinmann Type 730 caliper brakes

Weinmann Type 730 caliper brakes

When I first took the wheel off the bike to look at the freewheel I saw that the brake pads were seriously worn and needed replacing. So off I went, bought some need pads, and came back to fit them to the bike. But I thought I should check the rest of the braking system to see if I could make it work better. There is a problem where the brakes don’t pull and spring back evenly, and have a habit for one side staying close to the rim even after adjustment. I searched internet for some help on caliper brakes and these particular brakes (Weinmann Type 730) and found that others have had the same issue.

I also discovered that these brakes require a special tool for centring. I tried adjusting the clearance of the pads and also the centring of the brake unit but still had the problem of the brakes sticking. This could be due to old brake cables, but also it could be due to the pivot in the brake assembly sticking and not releasing properly – possibly due to a perished plastic bushing in the brakes. This leaves me with a few things I need to fix:

  • I need to replace the cables (something you should do in general maintenance)
  • I could clean and grease, find a new plastic bushing and buy the special centring tool, or
  • Find a new set of brakes.

I would like to keep the old brakes to keep in with the theme of refurbishment, but in the event that I can’t find the components to repair them I’ll have to buy some new. The new brakes would have to fit onto the old frame with the nut-and-bolt fitting and the have same reach  (Sheldon Brown explains caliper brakes). I’ve already found some that look like they’ll do the job, a pair of Tektro R556, which have been suggested in some forums as good direct replacements for Weinmann Type 730. Currently I can’t use the bike because of the brakes (or lack thereof), so this is now the number one priority.

Problem 2 – the wheels

The circle of refurbishment continues with the wheels. I’ve talked about the rear wheel and the conversion to a single speed freewheel previously. I decided that I could:

  • modify the existing hub and wheel – requires a new tool to remove freewheel
  • build a complete new wheel with new parts from scratch
  • buy a ready made wheel either in the shop or on ebay/London fixed gear single speed

At the start of this project I didn’t consider the any aspects of the wheel except how I could make it single speed.

Serrated front wheel rim with brake pads removed

Serrated front wheel rim with brake pads removed

However, there is a lot more about the wheel that I need to consider. Firstly there is the size: I have 27″ rims (630mm), which are larger than the modern rims (designated 700c (622mm) – see here for wheel size explanation). The size of the brake drop needs to be considered when changing the size of the wheel. Secondly there is the material – my rims are steel and aluminium tends to be the modern standard material. Also, the front wheel rim is serrated, which means it’ll probably make unwanted noise under braking not matter how which brake pads I use.

This is a lot to consider – wheel specification, brake drop and drive train type. And on both the front and rear wheels. Probably the best option would be to find matching front and rear 27″ (so I don’t need to worry about changing the brake drop size) aluminium wheels with a singlespeed (or even flip flop) hub. Having said that, I can still cope with the wheels as they are, and removing the freewheel and redishing the wheel should be a relatively simple and inexpensive job. For now, I will keep the current wheels, only adjusting the dishing and replacing the freewheel.

Other maintenance

  • I’ll probably new tyres soon, although I’ll wait until I’ve finished deciding about the wheels first!
  • I need new tape for the handlebars as the old (sponge) grips have worn through.
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