I guess most owners of Dnepr MT motorcycles know how inefficient and unreliable its standard oil system is. Yet, several small improvements will turn it into a hard-working mechanism that won’t let you down ever again.
Well, I can name two reasons. The first one: probably the workers who assembled them were drunk. And the second one: hey, we had the f*cking soviet union here when those bikes were manufactured. During the times of the soviet union, the number of items produced was much more important for workers than the quality of those items, and KMZ workers (the ones that produced Dnipro MT bikes) were no exception. Their salary depended on the number of motorcycles assembled and not the number of motorcycles assembled correctly. You can’t even imagine what things I’ve been a witness of when dealing with cossack motorcycles. Maybe, I’ll write a post about it someday. Anyway, let’s get back to the topic. There are two weak elements in the oil system: an inefficient oil pump and pressure loss while the oil is transmitted to the crankshaft. Fixing those issues will make you forget about any problems with your oil system.
A standard oil pump that is used in Dnipro bikes is pretty simple: two gear wheels and an excess pressure valve. The gears spin and force the oil to move from the bottom of the engine to where it’s needed. Pretty often those two gears have big gaps between them and the cover of the oil pump. So you need to check whether your oil pump has such a gap or not. The first thing you should pay attention to is the cover. Its inner surface should be absolutely flat. If it’s not, it should be polished to become ideally flat.
After this you should check if the surface of the oil pump sides and the surfaces of the gears have the same height. Take the cover, which you know is perfectly flat, and place it on the half of the oil pump. If everything is ok, you should see no gap between the cover and the gears.
If you see a gap, the sides of the pump should be polished as well. When you rub down the sides a little, check the surfaces again. Once you see no gap between the cover and the gears, the job is almost done. The only thing that is left is to cover the sides of the pump with some silicon sealing compound and assemble the pump. Once this is done, you can be sure that the pump will provide enough oil pressure no matter how many rpm you make the engine to perform.
Yeah, I know, my English is horrible, so to get a better understanding of what I’m saying, please check the attached images.
The oil from the pump is pushed to the crankshaft in the place where the crankshaft is attached to the front bearing holder. BTW, here in Ukraine we call the front bearing holder the “guitar” because of its guitar-like shape. The problem is that the crankshaft and the “guitar” are made of different materials and thus have different deformation when being heated (i.e. when you have a lovely ride some hot summer afternoon). This difference in deformation creates a big gap between those two parts and that’s where you lose the oil pressure the most. And this gap gets even bigger with every 1000 miles you drive because of the engine wear. The good news is that a small modification can save the situation.
The International System of Units (Système international d’unités or SI) is the current international standard metric system and is also the system most widely used around the world.
You will be surprised, but adding 2 rubber rings will prevent the pressure loss. In order to apply those rings, you will need to create special grooves for them. Please refer to the image to see where the grooves should be made. The size of the rings should have the inner diameter of 34 mm and be 3 mm wide. We use metric system here, that’s why I gave you the sizes in millimeters, but you can easily convert the sizes into inches with the help of the almighty google.
As for the grooves, they should be only a little wider than the rings and should have a rounded shape. Please note that you can take the rings of another width, if you fail to find the 3 mm rings, the main idea here is to make them sit tight enough to keep the oil where it should be. If this is done correctly, the oil flow will be pointed strictly in the crankshaft and the oil pressure sensor.
The final step in improving the oil system of your Dnepr MT will be adding a small rubber ring between the “guitar” and the crankcase in the place where the oil channel goes to the pressure sensor. Sometimes the gap between these parts is too big and this causes the oil flow to spread in different directions. And this tiny rubber ring will prevent this from happening by keeping the oil inside the channel. Check the image to see what I’m talking about. There is no specific size for the ring, you can take any rubber ring you find and make the groove according to its size.
That’s it, now your engine will get enough oil no matter what and this will protect it from excess wear. Enjoy the ride because now you have one less thing to worry about 🙂
P.S. I did my best to make the article understandable for English speaking audience, but something tells me I might failed to do this. So, please do me a favor, let me know if you know how it can be improved.