Back to the Future II - or - Something for Lockdown Sir ?

It was on the way back from a business meeting in Paris, on Voyager; having been down in La Tour Blanche in 2018, that I made the decision, although the idea had been festering for many years.

Voyager 05 had just been around the clock so, I reasoned, I did not have a lot more to prove. Would I just carry on running it until either it or I expired? Since acquisition in 1994, I had always found that the Guzzi gearbox and clutch were never really state of the art and could always lead to embarrassing noises (a bit like elderly aunts). Reliant engines are hardly SOA either, but we’ll gloss over that for now.

Slightly earlier than the Voyager project, Guzzi had made the ‘Convert’. A rather portly twin, bored to 1000cc and sitting in the same Tonti frame as all other 850 Guzzi’s of the era, but with a Torque Convertor (fluid coupling) and a 2-speed box. An automatic, way before any rubber banded scooters hit the streets; along the lines of old American cars. Indeed, the Convert sold better in the US and still has a following there.

If the Convert drive was designed to fit inside the Tonti Frame, from whence came the gearbox on Voyager, why should the Convert drive system not fit into Voyager? Leaving aside issues like power sapping and heat accumulation, for which Guzzi had decided an extra 150cc was necessary. This would be an experiment rather than a bettering attempt.
A few minor issues , like no ATF pump (the Guzzi motor included an ATF pump running off the camshaft), no ATF reservoir or radiator, could in theory be solved, but how would a drive system designed for a 1000 V twin, cope with an 850 Reliant motor ? Gearing analysis looked as if it would be surprisingly under geared by quite a long way. 16” wheels add to that problem. Better under geared than over geared perhaps, at least to get off the line, if not for M/way cruising. But less power, more heat and more complication is not what a Voyager needs.

Spend Spend Spend
Nothing ventured: I started by acquiring the necessary gearbox from Pete Morcombe in France. He said he could not supply the clutch, but when it came, I discovered the clutch hiding in front of the gearbox. He had forgotten the difference between the Convert clutch location and the standard Guzzi flywheel clutch. It was steeped in ATF, so friction material required replacing, but at least the main components were there. Pete also had a flywheel and starter ring, in apparently good condition, but no Torque Convertor.
The exit shaft from the 2-speed box has 20 splines. Manual box has 10 splines. Stein Dinse in Germany provided the necessary 20/10 U/J albeit at a price.
A missing brass bush on the clutch shaft was bodged from a stock bush-maker.
The auto-box got cleaned up and sat around the garage for a long time,, then a Torque Convertor appeared on eBay during spring 2019. These are not the kind of thing an amateur can view and pronounce healthy, so I had to take it and assume the best.
A bit of investigation into oil pumps gave me a Mocal 12v pump. It said, ‘only switch on when temperature >70C’, but comparing oil and ATF viscosity convinced me it should be OK for at least summertime starts. I already had an oil cooler in the garage, from a previous dalliance with extra cooling, so now the major components were assembled.
I still however needed incentive to pull apart a running Voyager, in order to make something worse, if interesting. Enter Covid-19.

The plan was to split Voyager in the middle and replace the exposed ‘manual’ box. Dismantling revealed a lot of rusty frame components, so although the front half remained assembled; the most obvious rusty bits in both halves got treated.
Removal of the manual box however revealed that ‘swap’ was flawed – at least for my frame, which Royce had redesigned in 2000 to incorporate a rear radiator. The auto box had extra lumps at the back, and these fouled some frame tubes. Discussion with Royce indicated how these frame tubes could be resited and the necessary space created. Luckily my local MOT man’s brother is a good TIG welder and he did a nice job – once I had removed all components (e.g. embedded fuel tank) from the rear frame; not a small task. At least it allowed each component to be repainted.
Reassembly was slow (but then so was lockdown). I discovered how to extract sheared HT bolts from the crankshaft and even a sheared tap sent to repair the thread damaged by the extracted bolt. I also discovered that ‘my’ Torque Convertor was mis-aligned front to back. Guzzi have a whole page of tolerances for the TC to Clutch layout. I did try as best I could, but eventually just bolted everything up together and checked the starter could turn it.

The Series A Vincent now has another rival in the plumber’s bad dreams, Previously, I had many hoses on Voyager, what with my multiple radiators and electric water pump. Now I had another radiator, pump and reservoir for the ATF. Mocal pump went under the seat; reservoir in the back and radiator at the front, where the collection tank used to be. (water hoses altered appropriately).

long days passed
Eventually testing took place without bodywork, up the farm road; dodging dog-walkers but enough to show that everything actually worked, although not enough to test the real usability of the set up. It was suitably impressive to just pull away from a standstill, with no gearchange, no clutch and just a rise of the revs.
There are other issues. Fix up a speedometer (the speedo drive point on the auto is at a different position and won’t meet the existing cable). How hot does the ATF get? How low is the gearing on the open road? Will I cope with the lack of engine braking? Should I link the brakes like Guzzi did? Will my scrappy components hold up to daily use? Will I decide this has all been a ghastly mistake and revert back?

Updates to follow.

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I'm impressed by the way that this major "desecration of our engineering heritage" was completed just in time for the end of lockdown. All I've managed is to fit a water trap to the fuel system (thanks to "Classic Car bits" supplying a brand new original AC water trap/filter unit that, just, fits in an unexploited space), that should take care of the water in the ethanol fuel. I also changed the front wheel bearings which got picked up on the recent MOT as an advisory for slight free play. Now, at last, we know how long these expensive bearings last, more than fifteen years, longer than 80,000 miles, is about as close as I can get. Don't expect to live long enough to have to do this again.

Interested to see how you get on with the Convert. I drove Malcomes Convert Guzzi FF a bit, found the lack of engine braking fairly terrifying but was amused by the similarity to a big Merkan car. I've got a Convert final drive, (needs a new bearing) and the driveshaft kit, you can borrow if you like, I always fancied fitting it to FJ if I can make it pick up from low revs better. Andrew's 04 still has the original Convert final drive and picks up really well with a Weber 34mm on the modified stock manifold. My home-made manifold works much better past 4-5,000 rpm but is crap off the bottom.

Sorry about all this stuff about heritage heaps people, we'd all rather be riding the all-electric version...

Hybrid question

How do people think a series petrol/electric hybrid Voyager would work out? Good around town until the battery goes flat? Crap on motorways? Would you need a big battery for successful conversion?

Gear changing

Morning, Graham. Have you managed to get into top ( second ) gear yet? I hope it is a smoother experience that the manual Guzzi gearbox!!


I think I left it in 'Top' when I mounted the 'box

You are not supposed to change gear on the move.(not good for the dogs)
I believe Convert riders leave it in Top all the time, Although if you were doing a lot of town work, you might switch.
For that reason, I have not made any gearchange linkage, although I wil try to set up a lever/knob which I can access from on board.


Really there just isn't room. In terms of packaging it would be easy to put an E-powertrain in the Voyager space, the problem is the usual power management and battery cost issues (which is where my own attampts have stalled. But that Reliant/Guzzi assembly is relatively huge, packaging is pretty much the whole story of the Voyager design! Replace that with some modern, super compact, multi, with integral gearbox and so on and there might be room for a reasonable Hybrid package. But why bother? All-electric, combined with the quite good aerodynamics, would provide similar performance with better acceleration than the Reliant/Guzzi package, with range in excess of the C-evo.

Watch video's of older ICE Monotracers, compared to the all electric Mono racer. It's much quieter, less vibration, strong acceleration. A big improvement on a powertrain from the last millenium that's clearly having rather too exciting a time in a Voyager. I've said it before, 'the train for ICE powertrains has left the station. It was an electric train' Practice for the future, be ready for the present.

Gear selection

Sounds a bit like selecting reverse on a Ural I once owned. ( For three months! ) Not that I'm comparing your Voyager to a Ural!