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  1. Hi Folks, I am back at it after about 7 months of school and work taking up all my time. So, looking at my newly cleaned up cylinders at Autosport Seattle (awesome shop), and took the advice to just drive in a new bushing. It's a steel bushing blank that I chamfered and drilled to match the original and that looks pretty good. Now, I am working the piston rings. Unfortunately, I think I need some new rings. The gap on the left looks good. 0.55 mm gap (measured 25 mm down from the top of the cylinder). The right side though is 0.75mm which I read as out of scope - too big. I haven't messed with them, so maybe they shipped me a set for a different bore or something. Has anyone seen issues running a ring gap that big? The other issue is that my pistons came with no directions on ring installation. Here's what I have. What order/direction do they go? First off, I think this is the order of rings from top to bottom (right to left in picture): Chrome, stepped black, oil, then oil. Then, if that's the right general order, which way is up on these rings? They are asymmetrical. Here's the black ring, which I think is second from the top of the piston: Here is a close up of the oil ring: And here's a profile diagram of the rings. Again, which way goes up? Thanks everyone, trying to get this ting back together!
  2. Good plan. What material did you use? The bushing I took out was steel (or some alloy). Have you had any problems using bronze?
  3. That's a good link. I can't believe I've never seen that site! Unfortunately, they do not have that particular bushing (P/N 7201106). In fact, no one seems to have that part. Ural-Zentrale, Old Timer, Holopaw, East Highway...nothing. The inside of mine is badly galled so I'd hat to have to reuse it. Anyone have any ideas?
  4. I drove the oil pump drive gear bushing out to Rotate it. On closer inspection the inside is pretty trashed. Does anyone know where to get a new one? Looks like it’s steel which is weird - I would have expected bronze. Any suggestions? Sent from my iPhone using Tapatalk
  5. That's great insight - I will definitely check my gaskets to make sure I'm not blocking that off
  6. Thanks for the comments everyone. I guess that is what I was asking about, especially for the oil channel in for the crankshaft gear oiler. I just can't tell if the hole is supposed to be fully drilled out, or just barely opened up to the channel cut around the circumference of the hole in the block (like it shows in the picture). Based on the machining and casting of the block, I would not be surprised if it was improperly drilled from the factory. I am thinking of driving it out, turning it, and driving it back in. Or just leaving it. I think it likely fine the more I look at it. I just got a call from the machine shop today. The cylinders should be done tomorrow. He bored them to a .09 mm clearance on the piston which falls right in line with the 0.08 - 0.10 mm clearance spec I've been quoted. He also end-gapped the rings for me...what service! I'll post up same pictures when they're back.
  7. Thanks Racepres, that's what I was concerned with. It's a Dnepr and I do not want to reduce the pressure by opening up orifices. However, if they just "forgot" to fully drill out these oil passages...I wouldn't be surprised. Really, I don't plan to do anything unless anyone knows that they are supposed to be drilled differently from the factory. Thanks again for your comments. It helps to know I am on track!
  8. OK. Cylinders are at the machine shop getting bored to the correct clearance. They should be back next week. In the meantime, I am looking over the block. I was looking at the oil passages and saw two areas of possible concern. Looking for some advice on these. First, in the oil pump gear bushing, there is an oil hole that passes through to a small gallery. The existing bushing has a hole, about 1mm, maybe 1.5 mm, but it is well off center. i am assuming that is not that big of a deal, but the hole is basically at the very edge of the gallery. Does anyone have any input on making that opening a little larger? Second, in front crankshaft bearing housing, there is a small oil tube that drips oil onto the gears. That small tube is fed from a channel cut into the block, with a weep hole cut into the channel from the face of the block. The weep hole in my block is not cut thorough the full depth of the channel. It results in an opening of only about a 1 mm x 2 mm oval. Same question...should this be enlarged or should it leave it well enough alone? Thanks!
  9. I have used oldtimer a lot too and have always had good results. Uralzentrale is another pretty reliable source. Sent from my iPhone using Tapatalk
  10. Certainly true - nothing with this bike goes quickly. I get a recommendation for a machine shop in the area which specializes in old Brit bikes and vintage BMW airheads. I am going to see what they can go for me. Sent from my iPhone using Tapatalk
  11. Thanks guys. I definitely don’t feel qualified to try this myself. Unfortunately I’m traveling for work and can’t make the rounds this week. There are some good shops up here near Seattle that work airheads I’ll see what they recommend. Could just be a quick home, but I’ll leave that to the experts!
  12. Thanks Racepres. The cylinders were basically spotless when I picked them up. Even now when I wipe them down worth oil the rag is clean (except the light brown from the oil). Sent from my iPhone using Tapatalk
  13. HI guys, thanks for all of your quick replies. Y'all asked some very valid questions! NorthernDuck: The pistons I ended up getting were the ALMOT 78.96 mm. Now, if I remember correctly, it is because the cylinders had scoring that required quite a bit of material to be removed. Racepres - I am not familiar with the differences between those...but the cylinders were bored and honed with a nice cross hatch and were supposed to be ready to install. This the first time I've done a total engine rebuild, so I may be missing something. Russ Noe - thanks for the recommendation. That's not too far from here, I may check those guys out. Like NorthernDuck said, they did a good job with the work, I think we may have just miscommunication on the desired piston clearance. I took a look at the uralzentrale/oldtimergarage options and the best is that 78.9. However, they can run up to 78.93 and with my min bore of 78.991 that only leave 0.061 which is tight I think I'll search out a machining option first if I can to shave off that extra 0.06 or so and stick with the same pistons. I really appreciate all of your inputs! Thanks guys.
  14. So the advice I recently got was to just was apx 0.3 mm for the end gap for a 79.00 mm cylinder. I will work on that one. But there is a new problem. I measured the cylinders to see how my machinist did in nailing the 0.08-0.10 clearance we had spoken about (note that machining work was done years back when I started this last time and I have subsequently moved about 4 times...). I set my bore indicator to 79.00 and gave it a shot: It looks like it came up short. I don't know what I'm doing, so if anyone has any advice on my technique let me know. But, I think I need to find a new machine shop. Can anyone recommend a machine shop in the Seattle, WA area? Thanks!
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