Tuesday, April 05, 2016

Fiona Facts and Mods

Mostly as a reminder to myself in the future, here's some of the known facts and changes done to Fiona so far.

Here's how I came to be her owner:  LINK

Based on the VIN number off the motorcycle from which her BMW engine came from, it was a 1984 BMW R80 RT (800cc) that came off the factory floor in 12/83.  Below is what the motorcycle looked like, in fact, RichardM has one up in Alaska!

source: theboltguy
Specifications for the R80 RT: LINK

The URAL itself was a 1999 Patrol, with a blown 650cc engine that the previous owner, Bud P., had found neglected under a tarp in someone else's back yard when he was seeking a sidecar for his RT.

Long story short, Bud encountered issues with the clutch after some time of ownership and after it had been converted into a Ural/Beemer rig.   The link above explains it in more detail if your curious.

The conversion of the URAL gearbox was done by Richard Winter aka Bural on sovietsteeds.  He's a master mechanic and known for his knowledge and vast experience in doing these conversions.

The flywheel on the '84 R80 engine had to be removed and the 1976-1980 heavier flywheel installed by Bud.

Then, the clutch pack from a /6 model BMW engine is used along with the clutch disk from a /2 BMW clutch because it's got the coarse splines that mate up the to the input shaft splines on the URAL gearbox.

More details and pics here on the clutch parts involved:  LINK

The wiring work involves three wires from the URAL harness to connect to the BMW engine.

There's wiring that was done by Bud P. that I have to someday research and explore in order to understand what was done, but its not your standard URAL wiring harness I believe.  Suffice to say for now, all the lights work as they should.

The URAL frame blocks access to the cover behind which is the engine's oil filter, so each time that filter is replaced, one must drop the front end of the engine in order to get a the cover.  It's not supposed to be a big deal, just a bit of a pain.  I'll let you know how that goes in a future post.

The main drive shaft is the original one from '99 with the fine splines which is connected to the transmission donut by the yoke piece.  Newer URALs have coarse splines for more durability and the connection point is closer to the final drive instead of the donut.  I am ordering a newer drive shaft as Richard Winter has cautioned that the fine splines currently in use will inevitably wear out.

The rest of the rig is all URAL components.  So, the final drive, which is the 2WD version, is only designed to handle the torque delivered by the 650cc engine, or about 27 HP I think.  The BMW engine has 50 HP, so the rig must still be driven like it's a URAL or expect to be replacing the final drive in a very short time.

1984 BMW R80:
Power: 50 hp @ 6500 rpm 
Torque: 42.8 ft/lbs @ 4000 rpm

1999 URAL 650cc:
Power:  35.00 HP @ 5600 RPM
Torque:  33.1 ft/lbs @ 4800 RPM (according to the manual)

2014 URAL 750cc:
Power: 41 HP @ 5500 RPM
Torque: 42 ft/lbs @ 4300 RPM

So, 15 more HP and almost 10 more ft lbs of torque than the original engine and 9 more HP and same torque output as a 2014 Patrol!

Basically, she can do 60 mph all day, with Beemer reliability, and not break a sweat.  Probably can go faster but URAL rigs tend to get a bit squirrely at speeds above 70 MPH in my experience.

One does not own a URAL, if one wants to go fast.  Period.

There were fuel issues, most likely due to the engine sitting unused for a long period of time, that had to be dealt with once I got her home.  Carburetors had to be cleaned out, fuel lines unkinked, old fuel removed and replaced with fresh gas and different clutch parts and cable components sourced/modified by Richard Winter.

Her stock petcock on the URAL gas tank apparently doesn't flow enough gas to feed the two thirsty 32mm BING carburetors the engine came with from BMW (Bing V 64/32/353-64/32/354).  So Bud had run a fuel line from the bungs normally used for a crossover tube between the two halves of the gas tank; directly to each carburetor, installing a small valve/petcock to shut off fuel flow when desired.

Today, I got all the components needed to ensure either petcock can supply fuel to both carburetors simultaneously.  This is to avoid blockage of the unfiltered bungs in the fuel tank by fuel contaminants, tank rust, what have you.  While dealing with the fuel delivery issues, that had been a main problem, one bung would get blocked temporarily, leading to one cylinder getting fuel starved and the engine running like crap, with no power.

 Brass Tee Adapters used to allow either petcock (red handles)
to feed both carburetors.

The above arrangement is similar to what is on my '87 BMW R80, Brigitta, who's fuel tank has a petcock on each side of the tank.

Oh, and I got Fiona registered today as a Colorado motorcycle, so she's a Coloradan now!

Re-mounted the base mount for the pillion seat so I could use the pillion's grab handle, but removed the torn up pillion tractor seat for now.  I added some padding to the handle, now it's comfy for my lower back.



The journey continues to build up trust between myself and this URAL/Beemer Patrol Sidecar Rig.  She's running good, tested the new fuel distribution setup by closing off one petcock and running for about 3 miles then switching over to the other, and running the same 3 miles.  She did great.

Upcoming tasks:

  • Replace her turn signal flasher with a modern electronic one vice the existing thermal/mechanical one to save on electrical consumption.
  • Fabricate an air box to shelter her air filters from the weather, as you can see above, she's using cone shaped air filters or "muffin tops" to prevent stuff from getting sucked into the carburetors.
  • Replace the NGK spark plugs with BERU spark plugs which should last much longer.
  • Maybe, get better 6 Volt coils to get a hotter spark, presently getting a yellow spark from them.
  • Check the greasing of the sidecar and front wheel hubs.  Repack with grease as needed.
  • Hook up the auxiliary lights to a relay and drive them off the battery.
  • Route the crankcase relief tube to ground.
  • Etc....Etc...Etc....wrenching is one constant of URAL ownership.  :)


6 comments:

Bruce White said...

Better thee than me. big task but remember, blue is faster.

Charlie6 said...

Bruce, I'll race ya, up hill, into a strong headwind.... :)

RichardM said...

Now that this rig is running so well, which one is the "spare"?

Charlie6 said...

Once Fiona is as trusted as Scarlett that becomes a great question!

SonjaM said...

I really like this chronicles of Fiona. Good stuff, Dom.

Charlie6 said...

Danke SonjaM, its more of a record for me, but glad you didn't find it boringly mechanical.