engine 47 g80L

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
Locked
bostonted
Posts: 47
Joined: Tue May 03, 2016 9:30 pm
Location: norfolk

engine 47 g80L

Post by bostonted »

Hi what is a 1947 G80 L engine is it a standard g80 or a competition engine? looked at one on ebay ,but could not find it in any of my books?
User avatar
Rob Harknett
Member
Posts: 11236
Joined: Mon Jan 01, 1990 12:00 am
Location: ESSEX UK

Re: engine 47 g80L

Post by Rob Harknett »

Never was a G80L model, was there??? For some reason they refer to G80L also G80LS in parts lists and instruction books, but not in sales cats. or Glass guides.
User avatar
clive
Member
Posts: 5657
Joined: Mon Jan 01, 1990 12:00 am
Location: LONDON UK

Re: engine 47 g80L

Post by clive »

bostonted wrote:Hi what is a 1947 G80 L engine is it a standard g80 or a competition engine? looked at one on ebay ,but could not find it in any of my books?
Rob is right that the G80L description did not appear in sales catelogues ( although the G3L did) but did in spares lists. To answer your question it would be a standard G80 engine. No factory made competition engines in 47.
clive
if it ain't broke don't fix
bostonted
Posts: 47
Joined: Tue May 03, 2016 9:30 pm
Location: norfolk

Re: engine 47 g80L

Post by bostonted »

hi just found a old photo on the net apparently early post war g80,s where G80L stamped on the engines
577typhoon
Member
Posts: 29
Joined: Mon Jan 01, 1990 12:00 am
Location: BERKSHIRE UK

Re: engine 47 g80L

Post by 577typhoon »

I think you are mistaken Clive. There were a small number of comp models rmade in 1946 and another larger batch in 1947. Also G80L stampings on crankcases appear to have continued up until 1948 or 1949. Certainly the Matchless Maintenance Manual & Instruction Book for 1949 refers to the G80L.as well as the G3L.
User avatar
Rob Harknett
Member
Posts: 11236
Joined: Mon Jan 01, 1990 12:00 am
Location: ESSEX UK

Re: engine 47 g80L

Post by Rob Harknett »

According to sales cats and manufacturers details of models there was no G80L, some parts and instructions books state G80L on the cover, already said that, There were indeed a few comp models made, from 1946 onwards. Probably made to order for compt. riders. About 16 G80C in 1946, about 102 in 1947. That's based on frames numbers given to the trade.
The G80 used the 1939 G90 flywheels, I believe these clubman model 500 OHV flywheels were heavier than the prewar G80. Perhaps due to early post war shortages, some G80's may have got 350 flywheels. So to ID these engines they were given the L ( Light ) suffix as the G3L had. There were also some G3R in wartime and early postwar, again the R was to ID the engine was non standard. I believe something to do with having roller bearings. If anyone has an early G80L engine and can check the part number cast on the flywheels, they may find do not have standard 39-G9- E ?? flywheels. I am sure I recall reading all this somewhere, it has also been discussed many times in the past. Certainly the G3R suffix instead of G3L. One person collected many engine numbers from surviving machines stamped G3R, But that's really off topic although some what related, as the odd suffix was to ID a difference from what was a standard fitting. There may be some mention of all this in the book Profile of the G3L & G80 evolution.
577typhoon
Member
Posts: 29
Joined: Mon Jan 01, 1990 12:00 am
Location: BERKSHIRE UK

Re: engine 47 g80L

Post by 577typhoon »

MatchlessEngineReconditioned 013.jpg
You do not have the required permissions to view the files attached to this post.
User avatar
Rob Harknett
Member
Posts: 11236
Joined: Mon Jan 01, 1990 12:00 am
Location: ESSEX UK

Re: engine 47 g80L

Post by Rob Harknett »

Your barrel also has G8L , there is also a B stamped on your engine. This is another odd stamping, which indicates your bike went out with Bowden instead of Amal levers.
Locked