Forum

[Steve T]

Thought this might be of interest the only information on the stand said 1962 Royal Enfield racer, maybe someone on here will be able to fill in some history.

[Mark M]

This is a GP5, 250cc 2 stroke developed by Enfield on an Alpha (Bearings) bottom end. Geoff Duke was hired to lead development, there was also a scrambler version and I was lucky enough to get a sight of this even rarer machine last week as it happens. Figures for GP5 production vary but somewhere between 25 and 40 were built and most ended up with different engines fitted as the original was under-developed. There has been a revival of interest recently and some (maybe as many as 5?) are active in classic racing. One turned up at the Hitchcocks open day in 2006 in the care of the Henshaw brothers and did some spirited runs up the road outside the Henhouse, a truly ear splitting performance. The great Ken Sprayson who designed the frame for Renolds Tubes was also there and very pleased to see his work in action!

REgards, Mark

[Mark M]

Steve, reminder, Club night next week!

REgards, Mark

[Barry N]

Steve - it's a Royal Enfield GP5 250cc two-stroke racer. Developed in association with the Alpha concern, it was an "over-the-counter" (on sale) machine that was raced in the mid-sixties by factory-entered riders Gordon Keith and Percy Tait, as well as many private entrants. It was one of several British 250 single-cylinder two-stroke racers around at that time (Greeves, Cotton, DMW, etc), all of which were quite successful in the UK until they were eclipsed by the faster Bultacos and Yamahas.

[Bullet Whisperer]

Hi Mark, that GP5 belonged to Ken Sprayson and Ian was in the frame to race it. However, at a track day for some testing, the machine's performance deteriorated very quickly and a top end strip revealed the alloy piston was running directly in an untreated alloy bore !!! The story goes, the guy who rebuilt the engine for Ken doubted it would ever be started, never mind paraded or raced and to keep costs down, the bore was never nikasil plated. That pretty much put the tin hat on that one. Ian got to ride another, water cooled variant, but that came to an end after it locked solid during a race at East Fortune, with both Ian and a Suzuki Super Six rider coming off as a result. It has been four strokes only for us, ever since! Regards, Paul.

[Barry N]

Apologies Mark! I was composing my reply to Steve, and after I pressed "post reply", I saw that you had got in before me!

[Steve T]

Thanks everyone for your replies nice to be able to get the history of this racer.
Mark all things being ok will see you there
Steve

[Mark M]

Thanks Paul, i had forgotten that it actually was Ken's bike, I think he was on his way to the 1000 bikes at Mallory? The GP5 is such a pretty bike, way more attractive than the other 250 class alternatives at the time. Interestingly Enfield were also involved in the development of a possible 2 stroke roadster twin using another Alpha bottom end, this motor was called the Alpha Centauri. I'm not sure how much Enfield contributed but they provided 2 or more Crusader rolling chassis and there are some pics of a Works apprentice riding it. The scrambler I saw was very interesting too, the Owner had been in touch with one of the Works riders and said that in his opinion the Factory's intention was to get some quick wins and then sell a lot of bikes, they weren't really committed to a long (and sensible!) development programme. This seems to have been an all too familiar story at the time. Steve, see you there! By the way, where did you get the picture? There is a GP5 in the National Motorcycle Museum but that isn't the one in the pic?
REgards, Mark

[Steve T]

Mark its in the Haynes motor museum at Sparkford, Somerset well worth a visit, not many bikes but some beautiful cars.