1924 BSA 'L' underlever spring question.

[Geoff555]

Good evening all. Just got this, it was cheap and ideal for a project. The spring, not an original one was broken and had about 1/2" preload. But even at that it was quite hard to cock, any harder and I think it would feel stressed and harsh.
I obtained a new spring from Mr Knibbs with whom I have no problem at all. It has over 2" of preload, I could get it in, I think, but would never be able to cock it.
What please do you think would be a reasonable preload - 1" ??
Any help or suggestions gratefully received.
Thank you.
Cheers.
Geoff.

[Shed tuner]

just serviced my ~1921 L

Spring was basically a meteor spring, with about 2" total preload - that is just over an inch to press the end block down to contact, then about 3/4" depth of the threads on the block. The wire is around 3.0mm, with a soft wind (lots of coils for the length), which is important. Shoots nicely, and quite easy to cock, at 7 FP. I have no desire to try to inrease it, as it has a nice soft and fairly quick cycle.

HTH - JB

[Geoff555]

Hello JB thank you, I should have been more accurate perhaps, the spring is 23/8" to the end of the cylinder plus the threaded bit.
I will compare the spring with the Meteor dimensions and lop from there. I don't expect or indeed want a lot of power.
Thank you again.
Cheers.
Geoff.

[Shed tuner]

Hello JB thank you, I should have been more accurate perhaps, the spring is 23/8" to the end of the cylinder plus the threaded bit.

yeah, that's a bit much... I'd chop an inch off for sure... what thickness is the wire ? Coil pitch ? OD ?

(PS My meteor spring was chopped too)

[Josie & John]

Try Protek, their springs usually fit without modification.

Regards,

John

[Shed tuner]

Try Protek, their springs usually fit without modification.

"without modification" !?!? How quaint !