Author Topic: Need Help - BSA L32-4  (Read 221 times)

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Need Help - BSA L32-4
« on: 06 June, 2019, 20:26:27 »
Hey Folks,

iīm new here.
my friend died last year and i get his BSA L32-4 from 1931.

The problem is, she donīt start well.
when it is cold, it is still reasonably.
as soon as she is warm she does not want to start anymore.

Do you have an advice for me?

does anyone have a manual?
I generally look for documents about this motorcycle!

Thanks you in advance

Best Regard



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Re: Need Help - BSA L32-4
« Reply #1 on: 07 June, 2019, 02:59:06 »
Hello Niklas,
I am no expert, but here's my thoughts, for what they are worth:

There are a number of possible causes for a failure to start when hot -

1/ Every bike is different, but I had that problem when i first got my 1929 Sloper - it was my starting technique at fault, not the bike. I was flooding it. I found it would start easily as long as I made sure the air valve was open and I did not give it too much throttle. When it will not start, remove the spark plug and see if it is wet - this might show whether you are flooding it.

2/ Or, there may be a fault - one possibility is that the carb float bowl is getting so hot that the fuel is vapourising once you have stopped.  A way to reduce this is to turn off the fuel before you stop the bike so that the float bowl mostly empties.  When trying to start again, the fresh fuel entering the float bowl should be cooler since it is coming from the tank.

3/ Or, the magneto may be failing when it gets hot - this is quite common for old magnetos.  While you could check to see if there is still a good spark by turning it over with the plug out and earthed on the cylinder, this does not guarantee that it will be producing a good spark when inside the cylinder. If you see no spark when it is hot, at least you know that it is the magneto at fault.

I may have some reference information relevant to your bike - i will check tonight.

Best of luck :)  I am sure it will be a fun bike to ride.