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Hi All,


Now that the DKW is done and running well, i went out to find myself another project.


Recently i found a BMW R35, 350cc OHV motorbike .

Like most period BMW motorcycles it is driven by a drive shaft instead of a chain.

It has had a previous restoration on which they used some post war parts (headlight, front brake drum,...).


Engine doesn't currently run, will try to start it later. First need to check the Bosch Dynamo and SUM carburetor.

It has quite some play on the rear wheel, I guess the bearings might be worn.

Headlight stays have been mounted incorrect.

It's original color would have been black with white lining, but i plan to restore it as a Wehrmacht (heer) dispatch rider's bike.




Edited by Dodge'40-'45
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Found a nice Bosch Horn today.

Removed the whole rear wheel and drive. it's in quite good condition just the lack of grease made it sound strange.

Oddly enough, the brake shoes have been home made. Not exactly what i hoped to find,

Will need to source a couple of correct ones, will also check the front brakes tomorrow. Hopefully they will be originals.. :D






Edited by Dodge'40-'45
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Front brake did have the original brake shoes and they were in great shape.

I decided to take off the fuel tank and valve cover.

Valves look Ok, engine has good compression so i guess it'll run after i have reviewed the electrics.

The carb is an original SUM 741 which seems to work.





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  • 3 weeks later...

Started dissassembling the BMW today, The seat cover looks like it was made from a Lederhosen...

The thread from the exhaust is nearly gone, so that will also be a problem. They tried to fix it by drilling a hole in the cilinder head and fixing the exhaust pipe with a bolt.

The drive shaft broke during one point and was welded back together. However it doesn't seem centered correctly.


On the other hand, frame is in very nice condition, doesn't seem broken or even repaired.

Rear mudguard has some cracks and dents but nothing serious.


i've decided to not start the engine. Oil lines seem quite rusty and after the home made brake shoes, i'm not sure what to expect.





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dismanteling continues.

Got down to the frame today. Engine will need complete rebuild, gearbox seems ok but will also be checked.

The wiring on the headlight was really bad. They removed the original switch to place a more modern switch.

The front fork came of easier then expected. It's a telescopic fork which is not hydraulically damped, unlike the larger BMW models. It has a Noris ignition which is strange because it should be Bosch. don't know if this is original.

Will have to make new cables, the ones on it are way too long and they did all kinds of stuff to adjust them.

The headlight brackets are also mounted wrong, they are upside down and should switch sides.

The front brake handle was also home made.


Managed to find an original Drilastic pillion seat today, one more item off the list.


Next up will be getting the paint off the frame. And a parts list... :-D






Edited by Dodge'40-'45
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  • 4 weeks later...

Made some progress on the BMW.


-Frame is almost ready for painting, just need to weld some small holes.


-Disassembled the clutch, plate looks ok, but will get a new one while we're at it. Clutch was stuck when i got the



-New brake shoes and cable set arrived.


-Started work on the engine:

Clean oil came out of the engine, this might indicate it ran not too long ago.

Cilinder head is scrap metal. The thread for the exhaust nut is gone. Several cooling fins have broken around the spark plug, likely because of a spanner.

trying to find a nice one, haven't had any luck yet.


Cilinder and piston itself are in quite good condition, no grooves or play.

While trying to remove the crankshaft pulley, a piece broke off... luckily, repros are available.








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Had a look at the sump. Just had to make a small field repair to the oil filter.

Cleaned the ingition, looking for a set of new points and condensator.


Had a look at the carb, it's in quite bad shape, it's cracked so i'll have to source a new one.

Also had a look on the rear stand, has some cracks and needs some welding done.


One step forward,two steps back :rolleyes:






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  • 2 weeks later...

been a while since last post, lots of work happened.


Test fitted the stand, a new shaft for fixing was made.


The engine is ready for assembling. Sourced a new set of gaskets.

Had a look at the gearbox, cleaned it out. No major issues there.

Gears all seem ok, just need to clean up an old repair of the shifter.


First batch of parts is now painted in primer.





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Well another episode of the story..


After 3 weeks the replacement cilinder head finally arrived.

Decided to assemble both cilinder heads.

Disassembled the cilinder head that was on the BMW when it arrived first.

We had to improvise a tool for disassembling the valves, since we're only used to working with sidevalve engines :-D.


Does anything seem odd about the valves that where in it???

Yep, non original valves... probably car valves that they've cut down and grinded a new groove in...

with non original springs and home made adjustment screws.

I wonder how it would have sounded with all these modifications...


Well then i had a look at the replacement cilinder head.

Finally i had some luck, the valves there were original. Exhaust thread,rocker arms and valves were in great condition.

we just had to grind the valves, and then reassembled them.

I'm no expert on valve grinding but they've told me how smaller the surface, the better the valve will seal.

So seems about right, or atleast i hope.

The 6th picture shows the original groove of the valves.


i've read some stuff about replica carbs for these BMW, most say they are cheap copies which have problems idling.

I've decided to restore the original sum carb that was with it, although in bad condition and cracked, once done it should be as good as new.


Another part finished, next job will be clutch. got a new set of clutch plating while we're at it.








Edited by Dodge'40-'45
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Last week and yesterdays work.


Finally got to removing the flywheel. Had to improvise a tool. Another surprise... seems like the shaft was quite worn and they made a speedy sleeve to go over it and fitted an undersize seal. They also made a new wedge groove, and crudely welded the old one..

Luckily i found a replacement flywheel in Germany at quite a cheap price.

Crankshaft and bearings are in good condition, just need to clean out the housing.

Just need a new seal and then the engine and gearbox can be fully assembled


Adjusted some spokes of the rear wheel and removed the broken bearing of the front wheel.


Carburator is beyond saving, it's an original carb, it has a cold-start helping channel , but they removed the plunger and pourred tin in the channel.


Welded the rear mudguard. originally the mudguard and luggage rack are riveted together, we've separated them but kept the original rivets so we can weld them back on. it's the only way to get them both fully cleaned.

For some reason they also removed a piece of the rear mudgaurd stay. we had to weld a new piece on it.

just need to get 2 rivets now to make it look original again.


Some friends came over to fix some broken bolts, quite tricky drilling in an Aluminum crankshaft case.

But in the end they're all fixed.


Put new plates on the clutch.


Seeing all these mods on the bike and these crude repairs, i'm starting to think this bike was used for motorcross.

Which might explain the off-road rear tyre when it arrived...











Edited by Dodge'40-'45
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  • 2 weeks later...

Disassembled the gearbox,just waiting on some parts now to put it back together.

No major issues just some worn sleeves. one repair made on the kickstarter gear but it seems well done.


Painted and reassembled the horn.


Started derusting the fuel tank, electrolysis rust removal and a new coat after should do the trick.

Last picture is the result after 2 hours.


Generator is in good condition, thought the bearings were worn but after opening, it's just a lack of grease which made them noisy.





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Still waiting for engine and gearbox parts to arrive, so i decided to have a look at the rear drive.

With the cardan shaft broken, i was expecting quite a mess.

I heard some clunky noises when turning the pinion gear.

After opening up, it seems a lack of oil caused the noises. it had stood dry for quite a while.

just needs some new seals and it's good to go.


Also managed to reassemble the gear shifter. Just need to find the correct springs for the locking plate.

They used twisted copper wire to keep the bolts in place...





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Thanks' date=' the engine and gearbox housing are made of aluminum. I just used some steel wool to get the dirt off and then some aluminum polish.[/quote']


Wow thanks - why do I always assume things are harder than the obvious. :)



Sent from my iPad using Tapatalk

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Work goes on..

Engine is now fully reassembled and ready for mounting into the frame. Once it's ready that is. :rolleyes:

new gaskets, new crankshaft pulley and generator belt.

Just waiting on one bearing before i can put the gearbox back together.

next major problem will be the drive shaft.








Edited by Dodge'40-'45
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  • 3 weeks later...

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