The Harris G80


"Now whatsdis all'bout" asked the AMC Orthodox

 - and he should follow this link for a start:


This directory is a compilation of Harris G80 information, largely the work of Glenn Archer, but with contributions from elsewhere. Especially Roy Candler should have a mention, doing  a brilliant job acting as central point of communication both collecting, disseminating and promotion.


The “Jampot Technical Topics” article is from the AJS & Matchless Club’s Jampot website.  The author, Geoff Austin, died around 1997.  According to his widow, Joan, he had owned his G80 for about two years and in the first six months transformed it from a “source of despair” to a reliable and much used machine.  No major parts changes or large sums of money were needed, just “fine tuning”, especially the ignition apparently.  Unfortunately, although he was working on a technical tips document, all that’s left is the Jampot website article.


The “Rotax parts (larger engine).pdf” may be useful, but should be used with care.  The piston and cylinder information refers to a larger engine (650cc, probably).  If anyone can find the proper one, said to be Spares List 632, dated 09/1987, please contact Glenn Archer (see below).  Also, note that the military version, featured in files beginning “Rotax504(mil)” is similar to the one in the Matchless but the stroke is shorter, the camshaft different -–and there may be other differences as well.


Forks: the stuff we have on front forks is for a very similar fork but without the anti-dive units.


The Mikuni file is included because some owners have opted to replace the original Dell’Orto carburettor with one of these.


Errors, omissions, additional information

If you spot any errors or omissions in these articles, please let us know.  We also welcome new material, as the idea is to gather as much information as possible.  If you do some work on your machine that isn’t mentioned here, why not take notes and tell us about it?  Send your contributions to Glenn Archer at:


Disclaimer: although every effort has been made, we cannot guarantee the accuracy of, or accept any responsibility for, the information in this directory. 


Click the desired catagory below to go to the files:

Engine Part Lists Technical Tips  Misc. cycle parts