SWM Guanaco from Gori: completed bike

The finished bike; prepared for trials and ready to use. It’s now a Guanaco, but with some better bits

The project has finished, but has taken a little bit longer than expected: too much work and too much holiday.

The bike is now more a 1978 – 79 Guanaco than an 1981 Gori because of the paint scheme change, but it has the good bits (which as I have an original 78 Guanaco I can vouch for).

Completed bike

These include:
– clutch action. The engine is a 1981 133*** serial number rather than an earlier engine (78 engines are usually 110*** approx). One major difference in the later engines is that the clutch arm has ball bearing races which provide a smoother clutch action.
– Betor front forks and yokes. seem more responsive; slightly steeper steering angle also.

The engine pulls well and with the change of barrel and piston it runs really smoothly and has plenty of poke.

Original and the 'project'

Comparing the converted bike to the original 1978 Guanaco, there’s not too many difference. Most noticeable is the Betor front forks, and a slightly different steering angle. Apart from that, much of the bike is same, including frame, engine, tank, exhaust and the rear cush drive arrangements of the early SWMs

Getting there…

It now looks like a 79 SWM, but doesn’t really run like one.

The engine is back in the frame and running. The only problem was that whilst it was ok at tickover, there was a complete lack of power under load and it wouldn’t really rev out.

So, after think timing, disk valve, carb set-up, crankseals and all other nasty thoughts, 10 minutes in the shed with Gavin and hey-presto. Running it without the end-box on the exhaust and no problem. The exhaust back-box has never been cut, weighs a ton and is obviously blocked.

Looking the part

I used some petrol on it, followed by a blow-torch on a long pole to try to loosen the crud, but although better, its still not perfect. So time for surgery and cut it open and potentially remove some of the baffle plates. Did this on the Jumbo and its run fine since.

Ready to finish ?

Cutting the rear box open revealed the problem, one of the baffle plates had come loose and was pushed back against the next plate, basically blocking the flow and any power from the engine.

Surgery for exhausts

Got Pete to weld the box together again (did a good job) and resprayed it with stove black. Job done. Put a new front brake cable together and installed the new plastics. Completed bike.