W/E 30th March

The big unveiling this weekend. Dean traveled up to help split the cases on the RGA and RGS motors – well he did the splitting, why mess it up yourself when you know someone who knows what they’re doing?

Mechanic (Dean) at work

Mechanic (Dean) at work

Both engines have 120,000 miles on them but have never been opened since leaving the factory.

The RGA last ran in 2008 on the eve of the Laverda Club de France rally when it was declared broken with suspected failed mains due to the amount of noise coming out of it. At the same time the clutch had also started slipping to the point that it barely drove the bike. We therefore expected shot mains so were surprised that the crank looks good – well sort of. The mains look okay but there is severe wear on the alternator end where the sprag clutch bearing runs.

Worn sprag clutch bearing surface (crankshaft)

Worn sprag clutch bearing surface (crankshaft)

Here the shaft is worn from 30mm down to 29.79 and when taking off the sprag the ring gear had broken off its retaining tab which had ended up inside the alternator rotor. I can only think that this small sliver of metal getting caught between the stator and rotor was the cause of the noise – hmmm so did the motor need to come all the way down? Yes and no is the honest answer but looking at the wear the sprag ring gear would have kept on breaking.

'Clipped dog' on the fifth gear - is it worth replacing?

‘Clipped dog’ on the fifth gear – is it worth replacing?

The only other notable wear on the RGA was the gearbox where the fifth gear dog has been ‘clipped’. There was no selection issues when it was last on the road so I don’t know whether to replace this or not – thoughts welcome.

Finally the engine always leaked from the left hand side of the cylinder head and sure enough dis-assembly revealed a pinched head gasket ‘o’ ring which I guess was pinched when the motor was built in Breganze.

Guess this needs replacing...

Guess this needs replacing…

Next up was the RGS engine. Folk may remember this engine broke coming back from France after it had consumed all its oil. When the motor was opened it stank of burnt oil but I was surprised at how localised the damage is. The primary side piston is broken and has left residue on the cylinder wall and bits in the combuston chamber but that’s it!

Ally residue on the bore

Ally residue on the bore

The gearbox, cams and even the crank seem okay! Isn’t that amazing?

So in summary the engines with both 120,000 + miles on the bores are in not bad shape and thoughts can now turn to the possibility of a triple for the summer!

Koso prototype fitting - failed

Koso prototype fitting – failed

Sunday I fiddled about with the Atlas fitting a digital dash – not finished yet and for the time being I’ve taken it all off and will rely on a satnav if the Police come looking about…I like the look of the Koso far less cluttered and will probably be much more reliable than the rubbish speedo fitted!

A nice pair

A nice pair

So a good weekend in the shed and now maybe the blog can start talking about reassembly.


Nick 🙂


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