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Written by: Rod Knight Back in 1992 I met the parents of a then-new friend, Bill, who had purchased a 1974 Dnepr MT9 sidecar outfit on my recommendation. I'd gone to visit him to see if everything was OK with his new acquisition, and to ask whether he'd had any regrets about launching himself into the sometimes dark, forbidding world of Russian motorcycle ownership. I'd driven my own MT9 outfit there so that Bill could make some comparisons, and it was at this time that his Dad - another Bill - made mention of a bike which was languishing in an old barn in a village some 30 km north of Toowoomba that looked somewhat similar. Bill (senior) is another keen motorcyclist, his current mount being a 1985 Moto Guzzi California that I get to ride occasionally. The suggestion was made that we both ride up there one day to see this mysterious machine, but somehow we never got around to it and the weeks and months passed. It must have been more than a year later that I called in on one of my occasional visits, arriving just in time to see a shabby, rusty old black motorbike being wheeled into their garage after having been unloaded from Bill's ute. It was, as I suspected, the aforementioned bike from the village and it was a Russian bike - a Ural M63, in fact. It was in a dreadful state, and I didn't think it was worth doing anything with. However, I did take the trouble to check the rear drive unit to determine which crown wheel/pinion gearset the bike had been fitted with when it was being put together in the factory. To my surprise I counted just under four turns of the driveshaft to one turn of the rear wheel. So it had been blessed with 'solo' gearing! Very few Ural M63s had come to Australia so equipped! With a 1970 build date stamped on both its frame-mounted dataplate and engine crankcase, this machine was also one of the first Urals to have been imported. Bill had purchased the Ural with the intention of getting it running again, and, since it was missing many of its original parts perhaps build a 'special' of some sort. But the weeks went by without anything happening, and I thought that if I offered to do some work on one or two components for him I might start the ball rolling. Bill was more than happy for me to do this, and I was given permission to do whatever I liked. An old teachest full of greasy bits and pieces (including most of a spare gearbox) had come with the bike, so I started on these after ferreting out all the non-Russian stuff. I won't bore you with a step by step account of the restoration project as this isn't the subject of this article. Suffice to say that I spent the next two years restoring various components - working on them when time permitted - and eventually coming to the engine. During this period Bill had the wheel hubs powdercoated and painted one or two other pieces before losing interest as other, more appealing, projects came his way. He asked me if I'd like to buy it. At first I declined, having suffered many less-thanhappy experiences with a 1981 Ural M67 I'd bought new and run for 7 years and 67,517 km. I had two Dnepr MT9s I was very happy with, thank you, - a solo and a sidecar outfit - and didn't need to have an old Ural! Still, the offer of the M63 haunted me, as did the persistent Bill! By now I'd reached the stage where I could see that, in spite of its dreadful outward appearance the bike had not been abused, or damaged in a crash. The rear drive unit, for example, was like new inside - as was the gearbox apart from three of its bearings! Dismantling the engine confirmed the bike's good overall mechanical state. Apart from rust on the main bearings and a slightly corroded top ring in the left cylinder everything was in excellent condition. Well, almost everything - the valves and guides weren't too good, but that was to be expected. Eventually I gave in and bought the bike for $800. Everything that wasn't already at my place was promptly loaded into Bill's ute and suddenly my back shed was cluttered with a Ural frame and lots of other big metal bits. New ballraces replaced the original mains, the roller bearing big ends carefully checked (they were like new) the cylinders given a light hone to deglaze them (this also removing the brown mark where the aforementioned ring had stuck to the bore), new rings fitted to the pistons and the bottom end reassembled. The cylinderheads were submitted to a local engineering shop for bead-blasting, to have the valve guides reclaimed by the fitting of thin walled bronze inserts (much cheaper than having the guides replaced) and valve seats recut. Another Russian motorcycle-owner friend sold me 4 new valves, the valve spring caps were remachined and new bottom cups made to enable the fitting of highquality Jaguar valve springs and the future of the old M63 was looking very bright indeed. During the bike's restoration I had been corresponding with yet another friend, Geoff, who had owned several Ural M63s during his 20 year association with Russian motorcycles. He kept highlighting a problem he'd experienced with a number of these early models, namely, the valve timing marks stamped on the timing gears. (Yes, I've finally come to the subject of this article)! He insisted that some of them had been incorrectly marked - ie: one tooth out on the camshaft gear - giving retarded valve timing which was anything but conducive to either performance or exhaust valve life. The way to check this, of course, is with a degree wheel, but first one needs the correct timing figures - which I didn't have. However, I did have a lot of respect for Geoff's hard-won knowledge of Urals. Dneprs too, as he built a much modified and very clever 780cc Sports Roadster - complete with 12V electrics courtesy of a shaft-driven alternator from a Morris 1500 car - out of an old MT9 a few years ago. Consequently I kept his words in mind, although I still wasn't sure which way I should go. In the end I decided to consult an excellent reference book I have on engine tuning, written by an A. Graham Bell (not the chap who invented the telephone)! His chapter on valve timing was very informative. In short, it stated that advancing the cam would improve bottom end and mid-range power, while retarding it would decrease power in the bottom end and mid-range but may very slightly increase the top end. Advancing it from between 4 and 8 degrees would show a marked improvement in mid-range power, with some decrease in maximum power. This improvement at low RPM and in the mid-range apparently comes about as a result of a decrease in the reverse pumping action, which raises cylinder pressure. Because the inlet valve is being closed earlier, there is less mixture being pushed back up the inlet port as the piston moves up on the compression stroke. And because the exhaust valve is also being closed earlier, there is less chance of the exhaust gas turning around and being drawn back into the cylinder as the piston descends on the intake stroke. When I reinstalled the camshaft (after replacing the two timing gears as the originals were worn beyond "quiet" limits) I took the plunge and advanced the valve timing by one tooth on the timing marks, which, in Ural (and Dnepr) engines equates to 7.5 degrees. This meant that, when setting up the ignition timing after replacing the timing chest cover I had to rotate the points box to the end of its travel in order to get the timing correct. It was then that I realized that the new gears almost certainly would have had their marks in the correct places, but I decided to leave things as they were and see how the engine would run with its 'new' timing. It took nearly two more years to finish restoring the Ural. I had to track down a number of missing parts, including a front mudguard to replace the aftermarket plastic one and correct Russian handlebars in lieu of the bent, rusted Harley 'buckhorn' bars that a previous owner had fitted. I also had to make up a complete wiring loom from scratch, but this wasn't difficult as I simply used the diagram in my Dnepr MT9 manual as a guide. The strong original 'sidecar' springs in the front forks were replaced with a set of 'solo' ones from a later M8.123 model, while I had a set of softer springs specially made for the rear suspension units. And what's it like on the road? In a word - different! It's different to my previous Ural, the M67 (and yes, I know the cam lobe profiles are different on the later engines) and it's different to my Dnepr MT9. Mr. A Graham Bell's comments are spot on. Black Beauty - which I've obviously kept - pulls like a train from almost zero revs and is very torquey at low and medium engine speeds. Being fitted with the later K63 carburettors it runs cleanly at all speeds and idles beautifully - far better than my K301-equipped M67 could ever manage! It's something akin to an old tractor to ride. I don't really have to rev it or anything, and it's so beautifully docile I can chuff up to most corners in top gear, feather the throttle, negotiate the bend then pick up speed again without the need to change gears as long as I'm still travelling at 40 km/h or so. It laughs at steep hills, including the more than 2,000 ft. climb up the Toowoomba Range from the Lockyer Valley below. Yes, I know the low compression pistons (6.2:1) and heavy flywheel help the engine's low-speed tractability, but it's still markedly better than standard. Better, that is, until the revs rise to 4,000 RPM or so - where it quite suddenly loses interest and power begins to fall away. The owner's manual quotes the M63 as producing 30 HP 0 4,800 - 5,000 RPM, but I don't think Black Beauty is now capable of this. It feels as though it could produce 27-28 HP at 4,300 - 4,500 RPM, but of course I'm guessing. Sidevalve engines have power/torque characteristics like this, and I've always had a soft spot for big sidevalves. The bike has been back on the road now for seven years or thereabouts, during which time I've run up 15,000 km. Not a great distance, but I do have a lovely old Dnepr MT9 that I generally (but not always) use for long distance runs, and a 1971 Izhevsk Jupiter 350 I also enjoy riding. Would I recommend this 'mod' to other riders of Russian flat twins? Well, it all depends on what you want your bike to do. I'm happy riding my M63 at 80-85 km/h (3,300-3,500 RPM) when out on a long run, and this would be far too slow for most people. Fortunately for me there are many long, lightly-trafficked country roads in my area to take advantage of, but I wouldn't like to be riding it on a busy motorway. Like the other Russian big bikes, it would benefit from higher overall gearing - or at least a higher top gear - to make better use of its strong low and mid-range torque. And because alternative high gear sets are readily available (in Europe, at any rate) it's an option I have sometimes considered. |
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