Hints and tips
Posted: Monday 21st September 2020
2BA bolts – Looking for replacement bolts for the drilled and threaded mudguard eyes found on most 50s frames? I had the threads checked and was told that they are 2BA which seems right and I have been able to get some from a local tool shop in polished zinc finish with cheese heads at about £1.50 for ten with nuts. The shortest I can get are 1” so some sawing is necessary. It seems that they had some brass ones until recently but the stock will not be replaced – they say they cannot get them. I guess many owners take the easy way to tap out and fit 5mm bolts.
GB Brakes – Setting up calliper brakes such as GB can be a real pain as whatever adjustments are made by spanner the blocks always rub one side or the other of the rims after they are applied. Use a flat punch and a hammer to tap down the top of the spring opposite to the rubbing side until it clears.
How to improve the efficiency of your GB brakes (and don’t they need it!) – dab a little grease where the return spring contacts the stirrup. The theory is that this makes them work with less lever pressure – perhaps half-a-ton instead of one ton!!!
There is a way of restoring the earlier worn GB brake levers. These are the narrower ones where the hood is slightly darker than the lever and have a brass adjuster set in the top of the hood. They tend to get quite sloppy between the hood and the lever due to wear on the pivot. First remove the pivot, which is a shaft, threaded one end and with a screwdriver slot the other. Then touch out the holes to 5mm and cut down a SS 5mm bolt so that the smooth part of the shaft acts as a pivot and then cut the thread to the (very short) length required. Next slot the other end to take a screwdriver. This will only work if the pivot holes in the lever are in reasonable condition.
Cotter pins – Another tip for removing cotters (from a long established local bike shop). Undo the securing nut and turn off until it is half-on and half-off the thread. Instead of hitting cotter or nut with a hammer use a sturdy 5mm flat-head punch direct on the cotter, the punch will be located in place by the proud nut. The force created by the hammer then seems to go more directly to the job in hand and the cotter moves with less effort.
Spokes – Do you get fed up with counting spokes in a wheel to decide whether it is 36 or 32/40 hole? No need to do it. If the pair of spokes opposite a parallel pair are parallel themselves then it is 40 (or 32). If the pair of spokes opposite are crossed then you have a 36. Nip out to the shed and see what I mean.
Brake levers – I learned a new trick last week (who says you can’t teach an old dog….). I used to spend ages bending down and dashing back and forth when lining up the brake levers from the side. Then I saw someone just lay a round tube across the tops of the hoods and then line it up with the tops of the bars as seen from the front. You can do the lining up and the tightening in one go. I guess that not too many of our readers will be fitting modern bars with grooves for cables. However, if you are, and the bars have twin grooves whilst you only need to use one of them, just tape a spare trimmed piece of brake cable into the unused groove.
Cleaning alloy – I recently watched an old cycle tradesman clean up an old stem. He gave all the dull and marked surfaces a hard rub with a brass bristled brush similar to ones used to clean suede shoes (takes me back to my teens!). This got into all the awkward corners and crannies. He then gave it all a rub with some fine steel wool – the result was quite amazing. I often use soap impregnated pan cleaners to do the same job as the steel wool. However I bought a brush the next day (from a shop selling decorating brushes) and I use it just about every time I work on a machine. Ideal for fiddly bits like brake stirrups.
BB axles – John Spooner (many years in the cycle trade including building his own machines) tells me that as a general rule bottom bracket axle BW (Baylis Wiley) 14 is for double and BW 15 for single chainsets.
Sturmey Archer FM – Several people have told me that they have trouble with the Sturmey-Archer FM: they cannot get the bottom gear to lock in on steep hills – just when you need them of course. The secret seems to be to change the normal way into bottom, keep the pressure on the trigger and start pedalling (spinning freely is no good, some pressure is needed) until you feel the trigger go click as it moves in just a little further. This seems to do the trick.
Clamps, etc – To stop band clamps (cable clips, gear lever bands, front mechs, handlebar bottle-cage clips, pump-peg bands, etc.) from moving and/or causing marks. Coating the inner surface of the band with a thin layer of petroleum-rubber contact adhesive (Evo-Stik in the UK) works brilliantly. The glue must be allowed thoroughly to dry before fitting. Bands treated in this way are much more solid and less likely to move or mark the surface.
Setting up gears – it is much easier to set up gears minus the chain. This way you can do adjustments and line up the changer with either end of the sprockets or chainring. When this is done, put on the chain and adjust tension if needed.
Chainwheel – if doing work on pedal or cotters with a double chainset, keep the chain on the outer ring. When, not if, the spanner slips you don’t end up with perforated skin where the teeth dig into your hand.