Good morning, after totally dismantling my old BSA and reassembling it I was astounded that it actually started and I took it for a spin and everything seemed to work..... however since then it wont start and I can't work out why, It's got fuel in the tank and it's getting to the carb,the jets are clean and clear,the battery is charged and it;s got a good spark so has anyone got any ideas as to what could be the problem ? I'm only asking on here as I can't get an answer from the BSA owners club !!! TIA Pete.
BSA not starting
- Thread starter don't come monday
- Start date
Model and Year of the Bike would be helpful???
Does it have a choke and are you using it? Old things don;t like to start without a lot of fuel
We have become very accustomed to the modern stuff Press button and go
And of course If you are starting a Diagnosis? I would do a Compression test first in case a tappet has backed off or something weird like that
Does it have a choke and are you using it? Old things don;t like to start without a lot of fuel
We have become very accustomed to the modern stuff Press button and go
And of course If you are starting a Diagnosis? I would do a Compression test first in case a tappet has backed off or something weird like that
Timing slipped?
wildbeeste
Registered user
You have tried all the obvious.
Try the less.
Is the exhaust letting enough through?
Has a baffle collapsed partially blocking it.? I don't expect you need to ask why I suggest this. This happened after a spectacular backfire though internal rot could have caused it at any time.
Try the less.
Is the exhaust letting enough through?
Has a baffle collapsed partially blocking it.? I don't expect you need to ask why I suggest this. This happened after a spectacular backfire though internal rot could have caused it at any time.
Try the extra fuel button on the carburettor ie 'tickle it'
Sounds about right for B.astard, S.topped, A.gain;; been there a few times; 
chasr
Registered user
Check the spark plug again, after you have tried to start it. Does it smell of petrol (damp). Check the gap, and its condition. And look for cracks, or change the plug.
If the plug is new, the gap is good, you can see or it smells of petrol, and you have a good spark, then it’s probably timing.
If the plug is new, the gap is good, you can see or it smells of petrol, and you have a good spark, then it’s probably timing.
1968 D14/4
I wonder if a crankcase seal has got a nick and failed ??If you take off the carb and cover the inlet do you get a "decent" vacuum when turning it over on the kickstart?
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Are you sure it's not just flooded, or the plug 'whiskered'?
If the primary compression is OK, maybe try some easy start & a new spark plug. Alternatively clean the plug with a blowlamp.
IIRC these late model Bantams ran with an Amal concentric carb - could the float needle be leaking, or is the pilot jet blocked? Have you got an in-line fuel filter installed?
If you suspect an exhaust side blockage, just remove the silencer. Presumably the rebuild included both new points & condenser.
If the primary compression is OK, maybe try some easy start & a new spark plug. Alternatively clean the plug with a blowlamp.
IIRC these late model Bantams ran with an Amal concentric carb - could the float needle be leaking, or is the pilot jet blocked? Have you got an in-line fuel filter installed?
If you suspect an exhaust side blockage, just remove the silencer. Presumably the rebuild included both new points & condenser.
does it have the points/distributor on a mushroom ? if so it could be the bush at the bottom of the drive. i had a 65 c15 which had that problem.
As others have said , timing . Also have you tried a new plug , plugs can fail under compression. Have you also tried a whiff of easy start into the air filter. Even with a weak spark you should get something even if its only a backfire. Have a bit of sand or a bucket of water if it does backfire.
Lastly have you tried bump starting it as that gets the petroil mix around the system even if the crank seals are on their way out.
Timing check for a D14/4 here if you haven’t seen it already
Lastly have you tried bump starting it as that gets the petroil mix around the system even if the crank seals are on their way out.
Timing check for a D14/4 here if you haven’t seen it already
Well thats that then...... points reset ,new plug,easy start and she's purring like a kitten.... thanks to everyone,, still no reply from the BSA owners club though !!!
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