Hello,
For those of you following or who are interested, we are still working on the bikes. It seems like it’s dragging right now. We’re almost finished rebuilding the ’94 engine with only a few last things to finish up. We need to assemble both heads (valves, rockers, shims, seals etc…) and put some pistons and rings in. Finish up on the clutch assembly which is half done and tidy up the left side engine covers and the stator and electrical seals.
The trailer has sat untouched through much of this work and time intensive engine building (which we will need to repeat one more time). It seems to us like we’re just slogging away and not accomplishing anything, but when we look back on the time we’ve spent on the motor(s), it will have been worth it — 70% of the bike is the motor and without that it’s a big heavy paperweight to push around Latin America.
What exactly are we doing to the engines you may ask? Good question! For starters we are tearing everything down to the last nut and bolt. Motorcycle engines differ from cars in that after you pull everything off the sides and top (stators/alternators, oil pumps, gears, starters, shifters etc…) you end up with two case halves that house the most basic functions of a motorcycle. This generally includes the crankshaft — the part that the pistons connect to and the part that makes the up and down motion of the pistons turn into rotating horsepower; the transmission — the part that turns rotating horsepower from the crankshaft into forward motion via various gears in this case being 6 speeds; the shifting drum — the part that allows us to shift through all 6 different gears and of course into neutral. Also included in the 2 valve 900 Ducati motors is the camshaft feed shaft — this takes the crankshaft rotation into a 1:2 gearing and feeds the belts that turn the camshafts in the heads.

Left side case cover, one of the last pieces to be reassembled on the bike
Of course all these internal parts need to be cleaned, however they also need to be reinstalled into their original cases after being inspected thoroughly. The caveat in our case is that the early Ducati 900 motors (among many other Ducati motors) used gaskets between the case halves originally. Well…they don’t make the gasket anymore, and we would like to later maintain the bikes without having to make gaskets every time we need to dig into the motors, so were using threebond to seal the cases. Threebond is much thinner (nil thickness) from the gasket (0.010″ thickness after being compressed). So every shaft needed to be re-shimmed. The shims sit on the ends of the shafts against the bearings, so its not particularly difficult to re-shim, but there is some math involved and lots of measuring, disassembling, checking, assembling, measuring…you get the picture.

Two case halves assembled (using threebond to seal). All the shafts sticking up except the center shaft with the arm needed to be shimmed for correct sideplay.

Two case halves assembled awaiting other parts. The hole in the side is actually the top cylinder. Inside is the crankshaft and connecting rod waiting for a piston and cylinders.
Once that huge step is completed, the rest of the parts were cleaned and slowly assembled in their correct order, everything was adjusted correctly and new seals and certain hardware installed where needed. We do have a good reason behind all this madness. We want to make sure these 20+ year old motors are good to go for the journey. The bikes have some attributes that we love about them, but also can be problematic in certain situations. The main attribute in this case being the air-cooled nature of the motors. This means that the motors have no coolant to check, water pumps or water lines to break, and no radiators to burst or smash on earthly objects; however, it also means that the engines need air moving over the large aluminum fins or heat sinks to cool itself. This could be problematic in areas where slow going (extreme muddy roads), slow speeds (cities, potholes, etc…), and high heat (between Mexico and Bolivia) are a factor…we may find a few of those areas along the road.
Ok, enough technical talk for now, on to other fun things. We went camping for fun over the weekend but it wasn’t all fun and games, we tried our new tent! It’s a Mountain Hardware Trango 3 tent. It’s an expedition-style tent with the only downside being less ventilation in hotter weather. It’s got a full rainfly with all clip on poles (no pole sleeves yay!!!). It sets up really taut and the quality seems pretty good, exactly what we were looking for. Since our budget is so low, the cheaper we live, the longer we can go, so we’ll be using it a lot.

Me posing while taking down the tent.

The tent all set up at night. Some reflective stuff!!!
Cheers!
Ehren
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