1971 BSA Lightning 650 engine stuck

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Nov 10, 2012
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The bike dont starts for more than 20 years.
The kickh start lever is locked and also the gear box shifter does not select the gears.
The gearbox is in neutral.
Where is the problem?
I thought at first to remove the LH cover taking off the chain transmission to see if the gerabox turns free.
What do you thing about?.
Thank you.
Piero
 
I don't think there is anything wrong with your gearbox, but after 20 years of storage, the pistons may be stuck in the cylinders.
Remove the primary chaincase and primary chain, and remove the sparkplugs, and try if you can rotate the crankshaft.
( I had the same problem with my Benelli that was stored for over20 years in less than ideal conditions)
 
Hi,
in any case do you think that i will have to take off the cylinder head to see the pistons?.
Thanks.
Piero
 
Piero, if the pistons are stuck in the cylinders, the head will have to come off anyway.
You could try to get the pistons moving again by pouring a mixture of 50% acetone and 50% ATF in the cylinders, and let it soak for a couple of days, and see if the pistons will free themselves from the cilinder walls.
I sometimes had success by using this method, but this does not always work.
 
With the clutch lever pulled does the kickstarter kick through? If it does that indicates your engine is seized. If it doesn't then it indicates you have a problem with your gearbox.

I once bought a BSA B50MX and the engine would not kick over indicating it could have been seized. But on that bike it turned out to be the kickstarter spindle's gear teeth had been broken thus jamming into the kickstart ratchet pinion. I know that a B50 is not an A65 but the construction is very similar in design.

You mentioned that your transmission does not shift out of neutral. That could simply mean that you have rust that built up on the shift fork selector shaft thus preventing the shift forks from being able to move. That happened on another BSA B50MX that I bought which helped me get a pretty good deal on buying that machine.

Of course it is really hard to say what the problem is until you open up the gearbox. Removing the gearbox is really a straightforward job. The only special tool you need is a clutch hub puller.

Peter
 
Could be as simple as a rusted primary chain that would give the same symptoms as a frozen engine...
 
pierodn said:
Hi.
With the clutch lever pulled the kickstarter does not kick through!.
Ciao
Piero

So you have a gearbox or primary transmission problem, (most likely the gearbox)
 
Peter R said:
pierodn said:
Hi.
With the clutch lever pulled the kickstarter does not kick through!.
Ciao
Piero

So you have a gearbox or primary transmission problem, (most likely the gearbox)

That is, if the clutch plates aren't stuck together.
 
I bought a bike from a guy who thought his motor was stuck after sitting for a long time and it was nothing more than stuck clutch plates,,,, got a cheap bike ,,,, for a cheap fix
 
I bought a BSA C15 250cc that had been rebuilt but would not start.

I swopped over the pushrods so the inlet cam opened the inlet valve, ex cam did the ex valve. It started first kick. Another cheap bike.
 
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