Engine swap

I have just started the process of swapping a recently purchased BMW R80 engine in to my Ural. I have finally thrown in the towel on the Ural engine as I am sick of the constant issues with it. The engine is fine when solo but is a bit gutless 2 up and tends to need to be thrashed to within an inch of its life.

I have been toying with doing this swap for a few years but the recent oil leaks which I can't stop have finally decided it for me.

So the first thing is too strip the Ural of its engine and gearbox. The gearbox will be mounted on the back of the BMW engine. This is the first item i need to sort. As the gearbox will need a bit of welding and the clutch plate off the BMW needs altering to fit the splines on the gearbox input shaft. Once the engine is out of the BMW and the gearbox is off i can see what needs doing to achieve the mating.

Here is the Ural minus its engine and gearbox. I have got its down to about an hour to drop the engine out.

http://i.imgur.com/YzzCe5R.jpg

Hi, would it not be easier to fit the complete engine and gearbox from the BMW and then hook up the final drive? Trying to match up that Ural gearbox to the BMW engine l fear would result in even more trouble.

Hi, would it not be easier to fit the complete engine and gearbox from the BMW and then hook up the final drive? Trying to match up that Ural gearbox to the BMW engine l fear would result in even more trouble.

The main reason to use my gearbox is the reverse. Plus there are various ways to connect the 2 items together so it's just a case of finding the best way

Well my first update on this project. The engine is out and round at my garage. The clutch has been taken apart and a new plate ordered from a German mate on my Russian bike forum. The gearbox is off being welded up and should be Back with me in a couple of weeks. I have took some photos and will update the stuff needed to fit the Dnepr box on the BMW engine.

But I thought while I am at it then I can fit the BMW handle bar levers and controls to my Ural. So after popping round my dads to remove them I tried to fit on on my handle bars. AARRGGHH . The bloody bars are 7/8 " ( 22.4mm) and the controls are to fit on 22mm bar. So after about an hour of filing with a round file the twistgrip and brake lever are mounted.

http://russianbike.co.uk/gallery/albums/userpics/10002/grip.jpg

I have now borrowed an adjustable reamer off my dad which should help to make it easier to fit the other side. I will keep the controls I have on the clutch side for now and will fit the new one once I rewire the bike next year. I am just going to add the wiring for the BMW to the loom I have fitted for now as i just want to get the bike running first.

I have just spent a couple of hours knocking up the clutch Pushrod and roughing out some ali spacers on my lathe.

These will be finished to size once my gearbox is back from the welders this Friday ( fingers crossed)

I have managed to find a place on Ebay which will make stainless exhaust pipes which are either swaged out or reduced in size. As I have the front curves of the old BMW pipes I will need 2 straight bits to link them up to the silencers. So a couple of straight pipes will do nicely. It all seems to be coming along nicely. Oh and a mate is coming round soon to help me sort out the wiring . Fingers crossed it will be back on the road for our Boxing day run.

We have major progress. I dropped my gearbox off at a welders a couple of weeks ago. He filed in the bolt holes and then added weld onto the location lugs for the Dnepr box. He also added a couple of bits of weld down near the lower bolt holes to match the location pads on the BMW engine. I have now been round a mates house and mounted the gearbox on a rotary table on a vertical milling machine. I then machined the weld down to replicate the original lugs on the BMW box. I did a quick trial fit tonight and the gearbox fits nicely onto the back of the engine with no play at all.

My next job is to drill the 4 bolt holes and then mount the gearbox properly. I have a plan to help mark these holes out. I will take some photos later and post them at a later date. But I am aiming for the engine to be back in this weekend.

I promised some photos so here we go. The gearbox is now loosely held in place by the top 2 mounting bolts. I am going to drill the other 2 holes tomorrow. I did wonder how to transfer the hole positions from the engine to the box and had thought of a few ideas. I settled on getting a couple of grub screws and turning the end to a sharp edge and then screwing them into the bolt hole one at a time and using that to make a mark on the case. Then I would centre punch this mark and drill the clearance hole. But unfortunately the grub screws I brought home from work were not metric. SO another plan was needed.

So I cut an M8 bolt down to give me a threaded length. I then turned one end slightly to remove thread and give me round part. I then cut a slot in the end to allow me to use a screw driver to turn this stud into the bolt hole. I then used engineers blue to cover the end of the threaded part. I then screwed this in so it was just proud of the mating face. I then assembled the gearbox onto the engine and lined it up into the correct place. I then gave the lug on the box a sharp smack with a hammer. This left a blue indentation in my gearbox face. I then centre punched this and then drilled it out. I then moved the threaded item in to the next hole and bolted the gearbox on with the one bolt.

So here is the gearbox roughly mounted to check its all ok. I am using the original air filter and will use the alloy spacers I turned the other day to connect up the air intake bikes. I am hoping to also mount the breather pipe in to the intake as per the original bike. I will have a lot of filing to do to clean the welds up.

http://www.russianbike.co.uk/gallery/albums/userpics/10002/gearon.jpg

There has been more progress. I have managed most of the weekend in the garage. Along side selling some bits of bike. Saturday was spent slightly hung over and then finishing off drilling the gearbox mounting holes. A mate popped round and helped me sort out which wires I need to connect my engine up. So I then ordered all my wiring stuff today. I have measured up the pipes and have ordered some swaged ended repair pipe in stainless to make the BMW pipes long enough to mount the silencers which I am ordering tomorrow. I have a week off in a couple of weeks so am trying to get everything I need for the final assemble.

Today I cleaned the gearbox bits up and started to rebuild it. First off I fitted new bearings all round. This entails knocking one gear off a shaft to remove the bearing as my puller wouldn't fit under the bearing to pull it. Half way through knocking the gear off I heard a sound and thought I saw something drop off the bench. It was then I noticed that there is a woodruff key holding the gear in place. Arse thinks I. But no worries its must be some where easy to find. After about an hour of looking I managed to find it. Only to see that the key was sitting only just proud of the shaft. So I decided to make another key up out of the head of a bolt. So a few minutes on the lathe and in the vice with a hacksaw and file and a nice new tight fitting key was made.

So the great assembly commenced. Bearing in mind I have taken a Dnepr box apart before. But it was fairly self evident how it goes once you start. Getting the 3 selector forks and spindle and output shaft in is a bit taxing . But after much swearing it went it.

Here is what the inside of a dnepr box looks like.

http://russianbike.co.uk/gallery/albums/userpics/10002/gearend.jpg

You can see the kickstart shaft lower left with the kickstart ratchet mechanism above it. The input shaft is the middle shaft with the output shaft next to it. The large gear on the end of the output shaft is the reverse. The plate at the top holds the smaller reverse gear. ( more of that anon). You can also see the 3 selector forks on the smaller shaft. I then fitted the end cover on the box and loosely bolted it up to try the gears. I then spotted that I had a spacer and a spring left over. Which when I looked at the photos I had taken when I dissembled the box were meant to be on the kick start ratchet shaft. Arse says I again.

So off with the end cover again and then fit these bits. I then fitted the cover again and tightened it down. The output fork was fitted and we were good to go. I then started on the BMW clutch. I worked out how this went together and loosely bolted it together for a trail fit. After about 3 attempts i managed to get everything lined up and my box bolted up and everything seemed to work. The engine moved when the kickstart was pressed and the gears selected and turned when the output fork was spun. I then thought that will do for the day and I will make the push rod up tomorrow.

Here is the box mounted and working.

http://russianbike.co.uk/gallery/albums/userpics/10002/revers.jpg

I just need to drop it off again to tighten the clutch bolts and stick the shake proof washers on. It was while I was sorting through my bits for my clutch for tomorrow that I spotted the reverse gear for my gearbox that I hadn't fitted because of all the dicking about I did taking the cover off and on. AAARRRGGGHHHH

So the bloody end cover has to come off again. That is the gear sitting on top of the box in the photo.

[emoji38] [emoji38] Sorry for laughing.....but that's the kind of thing I do....... [emoji38] [emoji38]

Np mate. But if it makes people smile then even better

I have actually ordered some of this for when I tackle the wiring. It getting very hard to find nowadays and I used my last tin up a few years ago. But I found this at an autojumble the other day.

http://russianbike.co.uk/gallery/albums/userpics/10002/smoke.jpg

I managed another few days in the garage. The good news is that the gearbox has been put back together with the reverse gear fitted. The clutch has been properly assembled and the gearbox is now bolted in place ready to mount in the bike. I also finished making my clutch pushrod and hardened and tempered it today.

http://russianbike.co.uk/gallery/albums/userpics/10002/push.jpg

Here is the finished item with the dimensions I used to suit the engine gearbox combination. I used 9 mm silver steel as that is easy to harden and temper with a blow torch at home. As I can't file either end now and they "sound" hard then I am happy with the result. If people want to now how to do this then post here and I can tell people.

I found out today my spare Amal choke lever will fit the BMW cables and also fit on my bars so thats one more job that I don't need to worry about. I have got an issue trying to line the air filter up with the carbs. But after a bit of trial and error and some on line searching I have managed to find some 50mm flexible intake hose which I think should do the job. So fingers crossed the lump is going back in the frame this weekend and due to having next week off work then I fully expect to have it mobile again.

OH and my exhaust parts arrived as well so I think I have everything I need to complete the bike.

Sounds like it's all coming along nicely mate....... nice job......

I'm enjoying this thread no end, I can't wait to see the finished combination. When I first started riding bikes in the 1980's, you could pick Ural Combinations up for peanuts. Not so much now. Keep it coming Gautrek.

Well another few hours in the garage have passed. Fingers crossed a mate is coming round tomorrow to help me lift the lump back in the frame. I decided while it was easy to work on to sort out the intake area today. My 50mm flexi intake hose came so I cut 2 pieces up and then mounted them on the carbs. The LH adaptor I had made needed its end turning down to suit the new hose and the RH adaptor really needs a new one making which is slightly longer as its a tight squeeze getting the pipe on. As its fouls on the top of the gearbox. But that is something to worry about in a while once I have proven the bike out. I also drilled and tapped 2 4mm holes through the gearbox casting into the 2 alloy tubes i made up to secure these into the air filter .

I also managed to make the BMW breather pipe fit into my housing. The original top pipe which mounts into the air box on a BMW was too short. I have pondered various ways of connecting the pipe to the air box. I thought of copper pipe fittings drilled and mounted in place and various other systems. But today I found the easiest way of doing it. I took one of the original pipes from inside the BMW air box and this slid up into the engine breather pipe. I then cut one of the original plastic pipes which used to fit in the intake tract and this mounted inside the smaller pipe. I will make a plate to hold this more securely in place after we fit the engine. But I am pleased with the result and it cost me no money to achieve. I just had to drill a 12mm hole in the air filter mount and then force the pipe through.

http://russianbike.co.uk/gallery/albums/userpics/10002/filter.jpg

Here you can the original breather pipe laying along the top of the engine with the smaller piece I slid inside. The white piece at the end is the original part which fits in the inlet tract on the BMW.

i know this is an old thread but I'd like to reach out to gautrek. I'm new here and not sure how to do this. I'm grafting a r60/5 engine into my DNEPR in the coming months and would love to see the images contained in this forum.

i know this is an old thread but I'd like to reach out to gautrek. I'm new here and not sure how to do this. I'm grafting a r60/5 engine into my DNEPR in the coming months and would love to see the images contained in this forum.

I have sent you a message.. with details of how to contact this former member.