STARTING: Like most classics, each will have its own idiosyncrasies. Some will need a lot of choke on the carburettor, a little retardation on the magneto and the throttle closed, others may need little choke, lots of retard and an open throttle, it's just something you have to get used to. The compression is fairly high but there's a valve lifter to ease that big piston over the resistance, though you'll still need a good leg. Those who fit electric starts are girls...
MAGNETO: A good magneto spark is essential, otherwise you'll kick yourself to death, invariably in front of an anticipatory crowd of onlookers. There are specialists who can refurbish the mag' or you can have it converted to electronics. They look the same.
CARBURETTOR: A GP carburettor is a pure race instrument. On track it's either wide open or it's fully shut, so a tick over is unnecessary. Make sure it's in good working order, Amal make then again, so if in doubt lash out and buy a new one, then live with it. If you can't, fit a new Concentric Mk2 or, heaven forbid, a Mikuni - if you can live with yourself!
#3 1963 650cc rocket gold star
The front brake is the eight inch single sided job, preferred by the racing fraternity, and works well, as does the rear brake.
Bearing in mind these bikes are half a century old, their performance Is remarkable and can surprise many a sports bike. It's time to take a look at the GP carb' on this one though as on a feathered throttle or at mid point, the engine hunts as the worn slide flops back and forth - at the top and at the bottom It's as sweet as a nut, so that's the next job I guess.
The 500 doesn't feel that fast when riding but an occasional glance at the speedometer soon shows that the feeling Is deceptive, le you're probably travelling much faster than you Imagined. We checked the speedo readings against those of a sat nav In the car and there's little more than a few mph optimism.
The get-away warrants a little clutch slip but can be quite civilised once rolling, only necessitating more when a Grand Prix start is required - not endearing to the neighbours, but sounds brilliant!
The RGS Is a well-told story of how Goldie specialist Eddie Dow was asked by a customer to fit a Super Rocket engine Into his Gold Star. As the Goldie was at the end of Its days, Dow suggested to BSA that such a model be made to use up Gold Star parts. Essentially that's what the company did, albeit making a frame especially for the RGS rather than using the stock frame for the singles. The RGS is the only frame In the twin range, which sports the letters A10 - all others are A7.
This particular RGS had been in one family from new, swapping back and forth from one brother to another and from the UK to the USA and back. Somewhere along the line It has had a bottom end conversion and now sports an end fed crank.
The genuine mileage covered Is thought to be reasonably low, and it's known to have been stored up for several years, so perhaps It suffered then as It has obviously been rebuilt and Is now very smart. Like many similar machines, if it stands for any length of time, the oil drains Into the sump, but there's an after market sump plate fitted with a large hexagon drain plug fitted, which makes draining the sump a two minute job.
It's got a very healthy compression ratio but starts easily with a hefty kick and the stock Siamese exhaust sounds terrific through the single Goldie silencer. The Monobloc carburettor gives a perfectly even, steady tick over and the four-spring clutch is remarkably light in use and works well with the RRT2 close ratio box. On the other side, the 190mm front brake is well set up and works smoothly.
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