Restoration of BMW R69s engine

[Janderso]

Mal,
You obviously enjoy it, good for you.
There is something about riding a powerful motorcycle on a country road when all is right with the world.

When I was a kid I remember my grandfather telling me about riding his Indian. I think the seed was planted.

I had a Suzuki twin 350 as a sophmore in high school. My dad took an R69 BMW boxer in trade.
He said, come on by the store tomorrow on your way to work, I have something to show you.
There before me was this beautiful black motorcycle from the movies. It took my breath away.
I took it out for a ride. The difference between the Suzuki toy bike and the R69 was night and day. The torque was something that took some getting use to.

I was hooked, I told myself there and then, someday my friend, someday.

 

[malmac]

Not all days involve working on an actual part.
Today I worked on constructing a pre-filter housing for the main filter for our new sand blasting cabinet.
Made out of 6 inch diameter heavy duty plastic pipe and other fittings.
Lid screws off so the filter material can easily be removed and cleaned or replaced.

Mal

 

[matthewsx]

Mal,
You obviously enjoy it, good for you.
There is something about riding a powerful motorcycle on a country road when all is right with the world.

When I was a kid I remember my grandfather telling me about riding his Indian. I think the seed was planted.

I had a Suzuki twin 350 as a sophmore in high school. My dad took an R69 BMW boxer in trade.
He said, come on by the store tomorrow on your way to work, I have something to show you.
There before me was this beautiful black motorcycle from the movies. It took my breath away.
I took it out for a ride. The difference between the Suzuki toy bike and the R69 was night and day. The torque was something that took some getting use to.

I was hooked, I told myself there and then, someday my friend, someday.

I had one of those Suzuki TC 305's, two cycle twin people would often mistake for a Honda. Until it took off....

JOhn

 

[malmac]

I had one of those Suzuki TC 305's, two cycle twin people would often mistake for a Honda. Until it took off....

JOhn

It is terrific to hear about the bike you owned. I have never had a 2 stroke bike. It seems I may have missed out on something special.


Mal

 

[matthewsx]

Not smooth like a BMW, but quick

 

[malmac]

Not smooth like a BMW, but quick

So is the model you had?



I had one of these.



"Those were the days my friend, we thought they'd never end" to quote an old song lyrics.


Mal

 

[matthewsx]

Yep, that’s the bike.

 

[Bi11Hudson]

A "beautiful" machine, the R69s. There was a "friend" that left one in my care when he went to sea. I rode it every week or so, to "keep oil circulating", bearings lubed, or something like that. I had a Suzuki 750j, a water cooled 2 stroke. The "Earles" front end and the shaft drive on the BMW was a handful for me, being used to chain drive models. He didn't have a sidecar, so it handled different from the Zuke. But I never dumped it. . . Even when the machine did a "nose dive" on acceleration.

A couple years back I saw a Ural with a sidecar. It otherwise was almost identical to the R69s. I have lusted after the BMW since I had my friend's, in 1972 or 73. So I was familiar with the appearance over-all. I "assume" the Ural to be a Russian copy of the BMW from the '40s. Though the Ural wasn't as "tight" or smooth like the BMW. Again, I assume the tolerances were looser to allow easier assembly. So I passed when I saw one for sale. But I sure did want a machine with the Earles front end.

But by the time I had the funds, the R69s were so "antique" they were hard to find. I ended up with a Moto Guzzi ex police bike. It had a shaft drive too, and the V twin ran good. But, Lord, the top end was noisy. I wired it to suit my thinking, and used Japanese controls. That Lucas (Prince of Darkness) electrical system had to go. And a (one) piston from, I think, a 1200 CC Volkswagen.

Should you stumble over one, Ural makes a sidecar that is almost a bolt-on to the R69s. With that Earles front end, it looks to be begging for a sidecar. A quick paint job to conceal the Russian ancestry and it would fit right in.

.

 

[malmac]

I purchased a new crankshaft for the bike, however when I put it to the test it is not quite aligned to factory specs, so it will need to be adjusted.
While the crankshaft trueing stand was the first step in assessing the crank, the next step is holding it while I adjust it with my hammer.
Today I machined up some custom blocks to sandwich the crank while it gets an attitude adjustment.
But to make the blocks I first had to make the cutting tool out of some O1 tool steel.
That worked out really good. Admittedly only cutting aluminium. I think the temper would need to be ramped up for cutting steel.

Mal

 

[C-Bag]

The predecessor to my R75/5 was a Suzuki 380. 3cyl 2 stroke. Pretty much bullet proof like all Suzuki’s. Pretty quick but definitely felt like a toy compared to the Beemer.