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I've been restoring a 1980 MT 10-36 since November 2015, largely aided by the numerous technical articles on this and other forums. The project is getting near to completion and I would like to share learnings and hopefully someone out there may find some part of this useful, as I have through the work of others.

 

Lot's of struggles, fun times, frustration and beer to get this far, on the home stretch now.

 

I purchased the machine locally from someone who had traded some of his time doing electrical work for this jewel he found in the back shed of his client. He came to the conclusion there was more work required than he originally estimated and decided to move it on. This was the first of many warnings I've ignored along the way.... The bike actually looked ok, a bit rusty and vermin had digested some of the softer components but you could feel potential. The rear wheel would not turn and the gear-shifter was seemingly stuck. No doubt a bit of oil here and there and it will be running in no time.

 

There was no title transferred at this stage, the original owner was deceased for many years and his brother sold it to the electrician I bought it off of. That's another story. Anyway, I'll post this just to see if it works (sort of the same strategy taken with every step of the restoration, where multiple failures are eventually forgotten by singular success....)

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The bike is a 1980 model, known as one of the 400 ‘wheat bikes’ shipped to Canada in exchange for wheat to alleviate Soviet crop failures as of the late seventies. I’ve only a single reference to this in spite of endless searching, and as of this day still do not know how they were retailed or what happened to the other 399 Ukrainian masterpieces. I’ve come across perhaps five of them in for sale adds, I imagine the other 395 rusted away. I’ve never actually seen a Dnepr motorcycle other than my own, they didn’t take root in Canada I suppose.

 

Well, it was sold as a 1980 but some of the parts that went into it were no doubt K750 era and other parts were recycled. Case in point, the gas tank had undisturbed original factory paint, but underneath were dents that had been filled. Early MT 10-36 motorcycles like mine were sold with K750 headlights and controls, I suppose KMZ had a lot of stock to run down post K750 production and didn’t want to waste anything. My theory anyway.

 

To get the bike off the trailer and into my shed, the sidecar was detached, then I unbolted the final drive, flipped it 180 degrees and reinstalled it so the rear wheel was disconnected from the frozen drive train. At least it rolled now. Interim arrangement shown below.

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I couldn’t get the engine to turn over by the kick starter or by levering the drive shaft propeller nut on the back of the gearbox. The bike had been left for unknown decades without spark plugs in the heads, ok, maybe the oil I squirted into the cylinders was an optimistic approach....

 

I removed the heads to get a look at the cylinders, valves etc to see why the engine would not turn over.

 

The valves and rockers were not pretty, corrosion on an entirely new level. Worse, no amount of application of the Soviet fine adjustment tool (iron mallet) would release the left cylinder from the piston within.

 

Plan b didn’t include penetrating oil, I cut the left cylinder, piston and connecting rod off with an angle grinder fitted with a cutting disk and accepted that road trials might be delayed by a few weeks....

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Heads with valves frozen in position, broken fins and not looking like a quick valve lap is going to get it back to factory condition. More later on what factory condition might actually mean.

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So I was resigned to having a valve job done. The broken cooling fins didn’t bother me too much, my plan was to take some of the fin material from the cylinder that I just chopped off and weld it in place. I have a small TIG welder but I had never welded aluminum, only stainless and mild steel. Can’t be that hard……later experience with welding aluminum tempered my enthusiasm somewhat. I repaired a cracked engine casing on my Ducati ST2, and although it was successful I admit the Egyptian pyramids were probably erected faster.

 

I was also in need of at least one new cylinder and piston, but eventually replaced both as the RHS had some corrosion and I was determined to make this engine purr like a kitten. I would later learn that ‘purring’ really doesn’t describe Dnepr engines, not that I dislike their character.

So back to attempting to turn the crankshaft, still no movement. Couldn’t be stuck pistons, let’s face it one is hanging in the breeze and the other just got cut off with it’s cylinder. I played with the gear shifter some more but no change there either, it still wouldn’t move even though the clutch rod could be activated. OK, either the crankshaft bearings are fried or there is something funny going on in the gearbox, time to pull both from the frame and have a look. After all, I had already accepted that this project might take a few weeks longer! I intended to paint the frame anyway, it was covered in bubbling corrosion, spiderwebs and let’s not forget home to whatever little rodents that had the seat and other components for dinner.

Picture shows scary spider webs. I should have hosed the bike down before putting it on the stand. Never mind, Dnepr restoration is a fearless business.

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Time to lighten the load. Alternator removed, coil, points assembly, front engine cover cables etc etc

I found the phone camera to be infinitely useful, I started taking pictures of wiring and other pieces so I would know where everything went. That was the theory anyway.

It was also time to drain the oil. I don’t have a picture but only those with cast iron stomachs could stand the smell of that filthy mixture of dirty oil, water, and fuel residue. Maybe the rodents used the open spark plug holes to relieve themselves, who knows. More of that characteristic smell was to come when other fluids were changed, more animal than mineral in nature and I think and I’ll just refer to it as km-zoil in future. The good news was there was no visible metal pieces in the mix, so maybe the bottom end hadn’t come apart?

 

There was something about the original Russian coil in the ‘mixing bowl of doom’ that I fell in love with. I pictured an old worker on a stool, pipe in mouth, patiently winding and taping with a bucket of varnish beside him. Like many loving relationships, this later soured but I had just married this Dnepr and the future was all roses.

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That lovely coil. I've seen many advertised by the parts sellers as the original coil, but I don't think there is any NOS kicking about as this coil is fairly sturdy with a bit of weight to it, unlike a replacement I tried. The heavy varnish just added that 'appeal'.

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BTW, if anyone knows the principle of the dischargers on these coils, I'd love to know. I always thought you just need two windings and the points to collapse the primary field, and bingo, high voltage spark from secondary winding to earth. There must be more to the story. B204 adjustment instructions attached, the gap is obviously important.

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I have a small TIG welder but I had never welded aluminum, only stainless and mild steel. Can’t be that hard……later experience with welding aluminum tempered my enthusiasm somewhat.

Right, aluminum is not easy. You need a AC tig welder for this. They are more expensive that the normal DC welder!

Great progress :smile:

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The coil is wired so that both spark plugs are in series with each other. One receives the + output, the other receives the - output. If one plug should become disconnected the other plug would not fire as the circuit would be open; the buildup of power in the coil could cause the power to break down the varnish insulation and ruin the coil. So they have a ground tab at each end that the spark will jump to if this occurs. Too small of a gap and the spark will prefer jumping to the tab instead of the spark plug. Too large a gap and it's too far for the spark to jump when needed, hence the specs on the gaps.

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You have quite the project bike there.

Yes, a removal from frame and full tear-down are in order.

Happy to watch your progress!

 

It's too hot to ride this week, with temperatures close to 100*F, and smoke in the air from California and Oregon (USA) forest fires to the south.

We have >12,000 fire fighters battling the conflagrations.

Crazy times, these. Good to stay indoors and work on restoring old motorcycles...

Or work on new steam locomotives, in my case.

 

Please keep posting your progress.

~RN

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Thanks Vance, I understand now and I wonder if I properly checked the original coil before assuming it was defective. I'll check primary resistance and if ok I'll spread the dischargers to ensure a preferential jump to plug. I have since replaced the original with an exterior-mounted oil filled unit after noting a loss of spark when the coil was hot. Regards, Colm

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Good luck Russ. I’m working in Greece this week where similar circumstances have caused a huge number of fatalities, wildfires spreading through communities.

 

I’ll post more this evening. Colm.

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