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Count Zero

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Everything posted by Count Zero

  1. Been away for a while - sorry for the slow response. The gears came direct from a Polish manufacturer years back, I'll have a receipt somewhere, if I can find it I'll post up details; Oldtimer Garage sell a choice of ratios including the unusually tall fourth - I'd be surprised if they weren't from the same supplier. I'm not sure Leszek is actually posting to UK at the moment though.
  2. I have an MT11-engined 2WD Dnepr. Because of the (very) low 2wd final drive ratio, during the last gearbox rebuild I went for the 18/28 3rd and the 23/23 fourth gears, to give a cruising speed of above the 45mph I was getting with the standard ratios. The third is actually good, giving a natural progression from 2nd and allowing the engine to pull well and a definite improvement. Fourth, however, is a massive jump up from that which the engine struggles to pull through unless on the flat or downhill; not too much of an issue round here in Beds/Bucks/Northants as there aren't even many slopes, let alone hills and I ride mostly alone and lightly loaded. Next time the 'box is open I'll be dropping to the 21/25 ratio though. I like the 2CV pipes idea. I'll be using that next time my standard pipe rots through. Which the low-quality parts available now seem to do very quickly - in fact the last one I bought wasn't even welded along the seams, and started rusting within a month of being fitted. Very fine outfit, by the way.
  3. You found the valve stem cap in the rocker cover? Now this would worry me. How did that come off? Can only be due to a sticky valve, did you check it for stem straightness? The low compression - are you sure your gauge is OK, odd to get the same low value on both cyls (I have had exactly that on a car engine I nearly rebuilt!). Correct pistons? Although I think the MT11 engine as in the MT16 has shorter pistons anyway.
  4. Dneprs come in two frame lengths, with the difference in length being 50mm (?) in the rear of the frame behind the engine. As the rear sidecar mount is also in this area, are there two versions of sidecar frame to fit the two frame lengths? Anyone have an illustration of the length difference?
  5. Thanks. I'd come to the conclusion that it must be the kneepad profile which differentiates them. My tank has quaint Soviet character in abundance - I think it's a deliberate feature, it must be quite a skilled job to make the welds look that bad.
  6. Are there any differences between a M-72 and a K750 tank? They look to be the same shape in pictures, but I’m not 100% sure. And do they all have the same diabolical welding quality which mine features?
  7. Not as confused as I am, Haj! I have absolutely no idea why I wrote retard instead of advance! Yes the ignition is loose advance, the rider pulls the lever towards him for starting and idling. Apologies for the confusion. I've only had my bike 31 years, not quite got used to it yet...
  8. On mine, the adv. lever does work its way back to retard. Not quickly, but I have got used to riding with the lever ball end jammed against my hand to keep it in place. Keeping the lever's fibre friction washer clean and dry helps things, but winding the lever screw down just makes it inoperably stiff. The points box rotation is metal on metal, and poorly controlled by the two attachment screws, so the stiff spring is needed to keep cable tension against all that friction at the business end. Just make sure it's all as free as possible and wear a thick left glove!
  9. Just thought members might like to know that due to a forthcoming move, Vostok Motorcycles http://vostokmotorcycles.co.uk are having to sell off a lot of their stock at reduced prices. They ship from Ukraine, I've bought parts from them in the past and found the service to be good, and the parts to be decent quality. I'm not affiliated in any way, just thought members may be able to pick up some needed spares at bargain prices.
  10. Might this from Oldtimer Garage fit? http://www.oldtimergarage.eu/album/air_cleaner.html As I understand it, the old type filter is a bit more complex than just dragging air across a steel wool (or rubberised horsehair) element. The upper, larger diameter portion is an oil bath, should have a quantity of oil in the bottom of the pan. Air is drawn in under the Bakelite lid, and then passes over the oil and up to the main intake (stuffed with fibres). As the air passes over the oil, particles stick to the oil and are filtered out. The steel wool is a secondary filtration medium. They were common usage on a lot of vehicles until the '60s or so, when the replaceable paper filter type came in which is easier to clean / replace, and traps finer particles than the oil bath. The oil bath is still used on some offroad and military vehicles as it can filter a large amount of dirt without reducing the amount of air it passes to the engine. On a lot of them, an offset intake pipe causes swirl in the oil bath part of the filter, centrifuging the dirt out. I can't see this feature on 'our' filters, unless the flow from the timed breather can influence the flow enough. Maybe a best of both worlds effect could be had by keeping the oil bath half, and replacing the steel wool with a K&N conical filter somehow...
  11. Got it, thank you for educating me. I'm getting the parts together to begin the rebuild now, I'll post pictures up as I go, when I can find the spare time to start!
  12. Thanks for that, it's as I thought, but I was worried I may be missing something. So it's just splash lubricated up there through the hole, with no oil grooves to distribute it within the bush.
  13. I'm planning a rebuild of my Dnepr MT-10/36 12v manual advance engine, as it's not been apart since put together in 1980. I did a top end overhaul a few years back, and at that time replaced the little end bearings. At that time I had some confusion about the oiling of the piston pin, as the bearing as received (factory part from UK dealer) was a plain bush, with no drillings or machined slots. Was this correct? What should the little end bush look like? How is it oiled up there? I want to make sure I get it right this time...
  14. Thanks for the suggestion. The inlet is a bit loose if anything. Weak spark may be the key though - if there's any valve sealing issues, that would sure exacerbate the condition, I feel a two pronged attack would be in order.... 1. Compression test, if down on the LH pot, whip off the head and investigate. Bet there's something up with the valve seat. 2. Chase through the connections from battery to coil, find if there's a volts drop anywhere, If OK, change coil. The sun is making a rare appearance this weekend, I feel I'm missing out now.
  15. I have a Dnepr MT11 engine in my hybrid MT10-36 outfit, replacing the original engine which is queued for rebuild. I'm having issues which I'm finding difficult to pinpoint. To start with the timing's fine, there's a reasonable spark and the K-65s are scrupulously clean. It starts on the LH cylinder, and the right will only chime in when choked with a hand over the intake. There has been spitting back on the RH, and a good deal of black smoke from the pipe. Both cylinders appear to be getting very hot, the RH maybe a shade hotter. There is very little throttle control, the bike seems to either want to race, or sit at idle. And, there is a strange chirping from the RH carb at idle. Compression seems OK on both, but having lent my tester to a friend I have no immediate way of comparing it accurately. It's the chirping noise and the spitting back on the RH pot which are worrying me; is this indicative of a sticky valve? Has anyone had these symptoms at all? And why is it always the sidecar-side cylinder which gives problems?
  16. The Kompressor itself was fixed to the front of the engine, breathing through a carb mounted on the upper RHS of the supercharger body and with long curly pipes under the cylinders to the inlet. This is a very nice RS54. Supercharging, iirc, was banned in international competition in '46 but was still legal for German competition, and the Kompressor (RS255?) produced till '50.
  17. No, the swinging arms differ on the drive side. 2WD has a C-shaped fork which attaches to the circumference bolts on the rr drive/transfer box; 1WD has a simple plate which bolts to four studs around the axle hole of the drive box. At least it will be an easier and cheaper task to source the 1WD swingarm. Why do you want rid of 2WD, btw?
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