AJS & Matchless Owners Club

Hi all I’m afraid there is going to be loads of questions on this project, but to start with valve springs….

The springs are very worn and all different lengths so don’t know what they should be but would they have only been made for the one or two years the 250 was made or would they be the same as other machines? Possibly later ones as I’ve tried the old part numbers to new but can’t find anything. The numbers are

Outer spring
serial number 191
Interchangeability ZB2240
Drawing number 16928

Inner spring
Serial number 192
Interchangeability ZB2260
Drawing number 16929

I’m also presuming that the top valve seat that holds the collets is called a “valve spring cone” and the bottom is called “valve spring dish” because the drawing is a bit confusing.

Thanks

Hi Neil

I assume that you are already familiar with the archive, doe this help with spring sizes? http://archives.jampot.dk/technical/Pis ... 0_1960.pdf

It may help if you refer to the bike by the model number as the big port name encompasses several models over the years.

Duncan wrote: ↑Wed Mar 30, 2022 3:41 pm Hi Neil

I assume that you are already familiar with the archive, doe this help with spring sizes? http://archives.jampot.dk/technical/Pis ... 0_1960.pdf

It may help if you refer to the bike by the model number as the big port name encompasses several models over the years.

1933 model 12 250 OHV "Big Port " all the Wolverhampton AJS got referred as an AJS Big Port. I guess AJS thought , you want it named as a big port OK.
So in the 1933 sales cat. they added big port in brackets into the model info. There's no info in the archives files for valve springs for 1933 model 12.

Thanks guys, I’ve found a set of valve springs on ebay that the measurements seem to be the same so have ordered them, there from France and the guy says they fit a WD so hoping they fit

Tazmantic wrote: ↑Wed Mar 30, 2022 11:48 pm Thanks guys, I’ve found a set of valve springs on ebay that the measurements seem to be the same so have ordered them, there from France and the guy says they fit a WD so hoping they fit

That sounds like Terrys VS82, they were common for OHV 250cc, 350cc and 500cc from the late 1930's up to 1947, I picked a nos set up at Kempton autojumble least year but was not sure how they related to earlier engines.

Cheers that’s sort of the conclusion I came to so I hope I’m right, they were not listed as vs82 just had measurements which all seemed close apart from the length but expect mine are well worn though his measurement of the small spring was about 4 mm longer than listed on the Terry’s list.

Neil