Britbike forum Forums British Motorcycle specific Brands Bsa bulletin board BSA A65 spring cup 68-0931 vs 41-0026

Hi,
what is the difference between these two lower cups for the valve springs? 41-0026 is the part number in the parts manual for 1966 models and 68-0931 in the parts manual for 1968 models.
Thanks,
Lars

i dont know

Hi,
I found out that the inner and outer diameter is the same on both but the thickness for 41-0026 should be 3/16" and for 68-0931 1/8".
It seems that the ones I have is 41-0026. Anyone who can share some light about what made the difference like shape, material thickness or..? Experience or advise for using the 41-0026 cups with the later springs?
Thanks!
Rgrds,
Lars

I'm fitting some Hepolite A65 springs but have found that they are nearly 1mm wider than the old springs, therefore won't seat into the lower cup properly. Does this mean some light grinding to fit?

1968 onwards, spring (outer) is 68-0930, cup 68-0931. For 66/67, spring 68-0806, cup 41-0026.

The cup I have measures 34.1mm OD, 31.4 ID, thickness is 4.67mm (3/16") the new spring diam. is 32.8mm, old one is about 31.5mm and is variable rate pattern.

The suppliers have not been too helpful so far.

If lars is correct that the inner diam.(ie, where spring rests) is the same on both part numbers, then it must be the new springs that are at fault.

Considering that Hepolite never made valve springs, the ones you have are Wassel owned Shite branded up as Hepolite (since they own the name, inc Lucas and Girling). I'd send them back and order the ones from SRM, the price for their springs is pretty competative and they are a good piece of kit.


Sorry I am not able to answer your question Lars

And the Hepolite shell bearings are Wassell too, Hepolite never made shells, AE Autoparts bought them from Glacier which was part of the same group as Hepolite at the time and all aftermarket pistons and shells were sold under the AE network in Glacier boxes for shells and Hepolite boxes for pistons and rings.

Hepolite shells seem to be consistently oversize so if you do buy them get your crank ground to the shell size not the factory size or you will lose a regrind.

Allan G
"Considering that Hepolite never made valve springs, the ones you have are Wassel owned Shite branded up as Hepolite (since they own the name, inc Lucas and Girling). I'd send them back and order the ones from SRM, the price for their springs is pretty competative and they are a good piece of kit."

Yes, I realise they were pattern springs, but presumed at least they would fit. Unfortunately I've had them since last March and only got round to fitting.

I'll see what the suppliers say.

Hi,
I got the measures for the cups from a dealers site and believed they were correct.. I could answer my question myself. Since I got the "old" cups and now both the earlier- and later springs I could see that the later springs don't hit the bottom of the cups. So either the later cups or the earlier springs for me. I think I will go for the later springs and order the later cups since it must have been a good reason for the change... The measures from semprini is the same as got from the ones I got = 41-0026.
Thanks!
Lars

SRM buy A65 Valve Spring Sets from Wassell!

I’ve had the race and standard spring sets from SRM and they have been very much different than the ones churned out otherwise. Maybe I have been lucky in the past. I have a new set to fit to a friends motor, I will have to check them.

Just out of interest, between '66, 67, 68 heads there are 3 different spring specs. I think some sellers quote the later part number for all years.