By joining you will help ensure that we can continue to provide this service
JOIN HERE!
1937 BMW R5 Restoration
- caker
- Posts: 236
- Joined: Sat Nov 12, 2011 10:49 pm
- Location: Haddonfield, NJ, USA
- Has thanked: 1 time
- Been thanked: 19 times
1937 BMW R5 Restoration
I bought this project maybe 7 or 8 years ago - a non-running (barely rolling) basket case. It was missing a few parts and was far from able to run, so I never messed with it -- it just sat waiting for its turn. Its history before me: it came out of southern California, and before that it was in Ohio. My impression is it was with that owner in Ohio for quite a long time. Amazingly, the bike was really well preserved. Lots of original fasteners and all the "weird" R5-specific stuff was more or less there!
Here's what the archive says:
> The R 5 engine-no. 501140 and frame-no. 502484 are matching. Your BMW R 5 was produced on 02.12.1937 [December 2, 1937] and delivered on the same day to the dealer Falcon Works in Isleworth/Middlesex, Great Britain.
A rare export bike! With a "miles" speedometer. I've reached out to the AFN / Falcon Works / Frazer Nash archive but have not been able to get any response.
Here's what I started with as I brought it over to my home shop. This was Aug 2023:
After some disassembly, I removed the motor and put it onto my engine stand. It did not take long to discover a major problem:
This was more a blessing than a curse - as apparently this was a common problem on R5s, and in my particular case it was a VERY clean break. The pieces fit back together almost seamlessly, so I wasn't that worried about a repair.
The blessing is because I believe this catastrophic fault is what put the bike up for so long in mostly untouched condition. Almost every fastener and all the sheetmetal was original, original speedometer, generator, horn, and so on...
-Chris
- caker
- Posts: 236
- Joined: Sat Nov 12, 2011 10:49 pm
- Location: Haddonfield, NJ, USA
- Has thanked: 1 time
- Been thanked: 19 times
Re: 1937 BMW R5 Restoration
Here is some welding advice my friend Kevin Koch in Germany gave me.
So between that advice, the "precision" jig I made, plus the perfectly fitting break, plus a really good welder and we got it back in one piece!
But what caused the failure originally? This was obvious: both the exhaust and intake valve stems were mushroomed out at the very top. The exhaust was way worse and this was the side that broke. So, I'm guessing the valve guide clearances were too tight and it started to hang valve(s) and, well, something's gotta break.
It is interesting to see the design changes that were made to heads from this generation onward. Definitely lessons learned by BMW...
-Chris
- caker
- Posts: 236
- Joined: Sat Nov 12, 2011 10:49 pm
- Location: Haddonfield, NJ, USA
- Has thanked: 1 time
- Been thanked: 19 times
Re: 1937 BMW R5 Restoration
-Chris
- caker
- Posts: 236
- Joined: Sat Nov 12, 2011 10:49 pm
- Location: Haddonfield, NJ, USA
- Has thanked: 1 time
- Been thanked: 19 times
Re: 1937 BMW R5 Restoration
Here is one of the "weird" R5/R6 specific hardware pieces. This is for the rear flip-up fender stay to the frame. It has a nut captured by a washer you'd stick on the end and then swage out the little nub to retain the washer. I had both sides!
-Chris
- caker
- Posts: 236
- Joined: Sat Nov 12, 2011 10:49 pm
- Location: Haddonfield, NJ, USA
- Has thanked: 1 time
- Been thanked: 19 times
Re: 1937 BMW R5 Restoration
- caker
- Posts: 236
- Joined: Sat Nov 12, 2011 10:49 pm
- Location: Haddonfield, NJ, USA
- Has thanked: 1 time
- Been thanked: 19 times
Re: 1937 BMW R5 Restoration
Todd Hanson out of Ohio did a great job on the pinstripes
-Chris
- caker
- Posts: 236
- Joined: Sat Nov 12, 2011 10:49 pm
- Location: Haddonfield, NJ, USA
- Has thanked: 1 time
- Been thanked: 19 times
Re: 1937 BMW R5 Restoration
It has higher compression R50S pistons and rods and a Chris Chambers crank that's been in a box for years. Reunited and the bike sounds good! Hoping for a nice day soon.
This turned into a photo dump, as I have about 500 pics so it's hard to choose, but it was fun to go back through all of them. Thanks to Jeff Moore for his help getting the plating and welding repair done. I also used PowerSeal USA for cylinder boring (they were awesome), and advice from Randy Long and many others - it takes a village. I hope I can help the next person.
-Chris
-
- Posts: 160
- Joined: Fri Oct 27, 2006 3:00 am
- Has thanked: 7 times
- Been thanked: 14 times
Re: 1937 BMW R5 Restoration
A job VERY well done! Congrats on a great outcome!
Chuck S.
Chuck S
-
- Posts: 250
- Joined: Sat May 15, 2021 5:52 am
- Location: London, UK
- Has thanked: 1 time
- Been thanked: 21 times
Re: 1937 BMW R5 Restoration
Charlie.