I'm making a start of season check list for my 1932 BSA W32-6, 500cc, 4.99 hp, SV. Could you please help me with some of the specifications?
1. Brake shoe thickness
2. Front and rear tyre pressure
3. Spark plug gap
4. Oil pressure as in indicated by in tank oil pressure gauge when running the engine
5. AMPs as indicated by in tank amp meter when running the engine
6. Cylinder compression when warm
HI, Brake linings should only need replacing if they wear down to the rivet heads.
Tyre pressures are not listed in any of the catalogues that I have. However tyre pressures vary with the weight of the rider. I used to have a W35/6 and ran it at 19 psi front and 26 psi rear. I weigh 13 stone.
Spark plug gap should be 25 thou.
Oil pressure with a hot engine should be approx 6 psi.
If you have a two brush dynamo charging will be regulated by the voltage control unit. If you have a three brush dynamo adjust the third brush to give about one amp for daylight running.Higher charge rate will boil the battery as you only need battery power for the brake light, if fitted, and the horn, if electric. M/cycles registered before 1935 do not legally have to have either a speedometer or a brake light.
This side valve is a relatively low compression engine and provided there is reasonable compression when operating the kickstart I would't worry about it. If compression is poor check the valve clearances first.
Thank you Alan that was helpful.
Could you also tell how much fee Play there should be on the primary chain and final drive chain please.
For primary chain you need to turn the engine over until you locate the position where the top run of the chain is at it's tightest. At this point there should be about 3/8ths of an inch up & down play. The same goes for the rear chain, turn the rear wheel until you find the the tightest point on the top run of the chain and adjust to half an inch up & down play.
Of course modern swinging arm bikes require much more play in the rear chain. Hope this helps.
Thanks again. Its' just this type of response that make a web forum a gold mine for those of us who are skilling up on old bikes.
Remember that tyre compounds used today give softer tyre wall so you should increase tyre pressures accordingly. I'd suggest you check with manufacturers pr supplier.
I would point out that tyre pressures vary greatly for the same size of tyre fitted to different bikes. It all depends on the weight of the bike plus rider. My 1929 BSA Sloper only has 18 psi front & 25 psi Rear with 325 X 19 & 350 & 19 tyres. However, my Rocket 3 which also has the same size tyres runs at 26 psi front & 30 psi rear although different types of tyre.
Unfortunately it is very difficult to find correct tyre pressures for pre-war bikes unless you are fortunate enough to have an owners handbook.
The tyre pressures given in the original manuals (if any were given) won't help much. Modern tyres, even with classical tread patterns, are constructed completely differently. The structure, the compound, etc. This means they require a much higher pressure than the originals. So it's very hard to say where they should be at. If one is lucky the tyre manufacturer will give you a recommended pressure based on load - weight of the bike plus rider. But again this is only a guide. A few psi difference can be the difference between a steady or wobbly ride, between comfort and vibrations and so on. On my Sloper I'm using 26psi on the front and 30psi on the rear. Can't remember exactly which brand I have - would have to check on the bike.