Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Pages: [1]
Pre War / Re: Starting problem after magneto rebuild
« on: 30 October, 2017, 19:05:56 »
Thank you everyone you have given me some great pearl of your wisdom. I will try them out and let you know the results.

Pre War / Starting problem after magneto rebuild
« on: 28 October, 2017, 22:41:09 »
My bike will not start. Please read all my post before responding

After having difficulty starting my BSA W32-6 4.99 hp side valve (1932) when it was hot I had the magneto professionally rebuilt. I was also advised by Tony Cooper who rebuilt the magneto that it would be more reliable to replace the original Lucas three brush dynamo with a later Lucas two brush dynamo; so I did. Hence I have a Lucas MS1 magdyno fitted, with a later Lucas dynamo.

Tony also advised me to replace the mechanical regulator, which was a coil on the back of the control panel switch (Control switch setting are off, charge, High beam and low beam). He told me it would be better if I replaced it with a Teb-tec solid state encapsulated regulator. Again I have done this.

When I replaced the magdyno I removed the cylinder head so that I could see that it was at Top Dead Centre, when the piston was at the top and both inlet and outlet valves where closed. I then located the magdyno into the sprocket with the ignition in fully retarded position. This is the method stated in the BSA Motor Cycle Instruction Book (All models 1930 to 1936 inclusive). The exact wording for all 1932 BSA motorcycle is:

Piston at T.D.C Ignition fully retarded, Contact Breaker points open .003

Before locating the magdyno into the sprocket I had rotated the contact breaker assembly until a cigarette paper could just move between the points and left it where the cigarette paper just comes loose. I made sure that it was fully retarded by not connecting the cable to the leaver, hence the cable was loose.

Both the inlet and outlet valve (Tappet) clearances are correct, .004 inlet and .006 exhaust.

When I attempt to start the motorcycle it will not fire at all. I tired starting the bike fully advance, half advance and fully retarded; however the outcome was always the same it would not fire at all. So I did the usual check for air fuel mixture and spark at the spark plug. I removed the spark plug placed it against the engine and yes there was a spark, also fuel was gently dripping out of the carburettor which indicates that the fuel was getting through.

Then I tried spraying Easy Start down the carburetter mixing chamber, again I tried bike fully advance, half advance and fully retarded. It would only back fire sending the force back through the kick start.

My question is how do I diagnose and remedy this problem.

Thank you for your kind help.

Pre War / Re: 1932 W32-6 running problem
« on: 09 July, 2017, 15:44:15 »
Okay, Ive been playing in the garage. I realised that after rebuilding the carburettor I had left the pilot jet (air screw)  full in. The bike would start but only run for  two seconds before stopping despite encouragement from the throttle. So I started to think that my problem was due to the air/fuel mixture being to rich. Easily solved I thought.

After attempting to start the bike with the pilot jet (air screw) at varying positions from fully out to fully in and seeing no affect I realised that it was not going to be that simple. Any way the pilot jet only comes into effect when the throttle is fully closed because it is part of the idle circuit and I usually open the throttle about one eighth open when attempting to start.

I then had a look at the spark plug. It was dry and black; a light rub showed a nice grey brown colour. The spark plug is a new KLG super M30 so I changed it back to the old KLG M30, but this had not noticeable effect.

I did have one miner success. The fuel was some times coming out of the top of  float chamber. It is a bottom feed float chamber. I looked inside the float chamber which is new and realised that the float needle had two notches so I placed the needle retaining clip on the lower notch, which means the fuel level will be lower in the float chamber. This stopped fuel coming out of the top periodically but did nothing for starting the bike.

The bike has been on the road running since I cleaned the tank out, replaced the petrol tap and rebuilt the carburettor, however at the moment it seems to only fire for two seconds then die. After this it will not fire at all unless I leave it for about 1 minute with the fuel tap off. What is this telling me?


Do you need one thousand words or just one picture?

Pre War / Re: 1932 W32-6 running problem
« on: 07 July, 2017, 22:03:57 »
Bike 1980 before retoration

Bike today

I think I may start by screwing out pilot air screw. If this does not work I will try lower needle one or two grooves. How does this sound?

Thank you all again for helping me, Im a newbie who is just starting to learn one end of an Whitworth spanner from another.

Pre War / 1932 W32-6 running problem
« on: 04 July, 2017, 22:00:05 »

Im looking for some help with my 1932/33 BSA W32-6 500cc side valve.

When I attempt to start the bike for the first time after a week or so it starts first time but only runs for a few seconds before cutting out. After this it is difficult to start; turn the petrol tap off and leave it for a few minutes and it will run again for a few seconds.

When I tickle the carburettor some times fuel comes spurting out the top of the float chamber (type 64/079). The carburettor is a Amal 6/112 fuel is seeping out of the primary air holes as it should, which shows fuel is getting through.

How do I know if this issue is relate to the pilot air screw, throttle stop adjusting screw, advance retard ignition lever or air valve lever.

What do you think the problem is? How can I diagnose the problem and how do I get it to run reliably?

If you have experience of working with this type of vintage bike I would love to hear from you. Thank you for any advice.

Ive taken resent ownership of the bike and here is a list of the jobs Ive done.

   Cleaned out the tank and relined it with a professional kit.
   New petrol tap
   Cleaned the Amal carburettor (Amal 6/112)
   Replace the float chamber on the carburettor because it had a crack then broke
   Changed the engine and gear box oil

I live in the Black Country, Cradley Heath

Pages: [1]