I've been extremely busy of late. Mostly helping my friend Matt open up his new retail space (http://metrixcreate.tumblr.com/ for a bit of info.) I'm pretty happy with the shelves I built. I designed them in Sketchup, cut all the bits and screwed it all together with only minor tweaks.

Tonight I installed a new exhaust system on the R50. I was going to keep using the one I had but I got fed up with how poorly it fit (it's for an R60) so I sprung for a new complete stainless system. It's an exact replica of the OEM system only in stainless so it will last nearly forever. I'm pretty happy with it. I no longer have dual exhaust leaks and that's a good thing. I finally got the rear brake shoe today and will install it as soon as I can. I've also got a seat mounting bushing to install which should firm up the ride a bit. After all that I need to get started on the sidecar.

The Rockster is still out of commission as I've not yet had time to replace the fuel filter. Thank you BMW for putting it inside the fuel tank. That's a great place for it I don't think.

On the fluffy flying friend front we have a new bird staying with us for a while. She (He? It?) is a baby black cap conure, about 7 or 8 weeks old at this point. She is smaller than Niko and incredibly cute. I've been taking her to work a lot, my coworkers seem to like her.

The Groovik's cube appears to have gone well. All of the photos look great. I hope we set it up locally one day, though that would take a lot of effort and a good chunk of cash.

Tonight gordonmessmer came over and we installed the exhaust system, put a bit of gas in the tank and did a few last minute checks. The engine started and ran on the second kick. This is even more amazing considering that we soon discovered that the left cylinder wasn't firing (pulling the plug wire did nothing to engine RPM.) Turns out that the left carb was completely dry. The float needle was jammed and there was no gas getting in at all. I cleared that and we kicked it again and it ran way better. Did another spark plug cap pull check and now it was the right side that didn't want to run on it's own. Pulled the plugs and the right side was running rich so after resetting the carbs and a bit of tinkering things were balanced up a bit better. Then the engine really wanted to run. It actually starts halfway through a kick now.

So I took it for a ride around the block. It's been so long since I've ridden it that I'd forgotten what it's like. It was a blast. Gordon had a goofy grin on his face when I accelerated past him on the street. I did a lap around the block with the transmission bolts finger tight to align things. Then Gordon tightened them down and I pulled it around into the driveway again.

I'm having a celebratory drink tonight. There's still some fine tuning to do, the timing isn't right and the carbs are still only coarsely tuned, but it runs and that's cause for celebration!

I pulled the R50 out of the garage today to do some work on it and was startled by how good it looked in the daylight. The clean engine makes a huge difference:



Tonight I filled the bike with fluids, gapped and installed plugs, checked the valve clearance and checked things over. I think that the last thing is the exhaust (that doesn't fit, but that's another story), fill the tank and kick it over. We'll see how well that goes, maybe tomorrow.

On the sidecar front, I pulled it into the garage and had a closer look. I tried to pull some of the nuts and bolts apart but they are pretty well gone. I think that I'll try using electrolysis to remove/undo the rust and see if that helps. In the mean time, have a look at the awesome plate that is mounted on the nose of the sidecar:

I spent most of Friday night playing around with a laser cutter. This is the best toy since the stick. Seriously.

Also, I am now the proud but slightly worried owner of this sidecar:



The price was very good, but it needs work. Fortunately all the parts that I'll need seem to be reasonably easy to come by. I think that I'll leave the boat looking ratty for now, it'll match the R50. The frame will need a lot of work though, and a new wheel.

Oh boy, I have another project. :P

One year after I bought the R50 it was once again in the driveway getting worked on:



I spent the day doing things like installing the carbs and electrics. Surprisingly the battery survived the long sleep with a full charge. I unwired it from the bike (previous owner had hard-wired it in) and cleaned up the connections a bit. While doing so the battery's fuse laid down it's life for the cause.

Click below for more pictures from yesterday. I'm so very pleased with how clean and shiny the engine is now.


There's still plenty to do, but I hope to try starting it in the next week or so. The only piece I don't have is a good rear brake shoe, so while I'll be able to start it I may not be able to ride it for a little while.

...but at the end of it I once more own two motorcycles rather than one plus a pile of parts. It's even close not running yet but all the big pieces are together and I sat on it (and made vroom vroom noises) and rolled it out of the garage.

Pictures to follow.

I'm completely wiped out today due to getting paged late last night for a problem that took a while to clear up. I had intended on sleeping in but had promised a coworker that I'd give him a ride to work so that didn't work out.



In the long run however, it worked out very well. Being completely out of it I couldn't really focus on work so I ended up looking on craigslist for BMW stuff. Right at the top was a listing for 'BMW Carbs' for $75 so I had a look. They were listed as being for a '55 R50 so I dropped the seller an email and figured I might hear back. A few minutes later my phone rings and I get his address and head for Burien. Upon pulling into the driveway the guy looks a little familiar. Turns out I met him once at a VME meeting. Why do I remember him? Because he used to own my bike. Yes indeed, the carbs he had for sale were the carbs that were installed on my bike at the factory. Epic Score.

They are in remarkably good shape considering they were pulled and tossed onto a shelf 30 years ago. The only part missing is a slide return spring and the only non-rebuild part that needs help is one of the threaded rings that hold the top on. One odd thing is the red/white dust that came out when I opened things up. I'm not sure where that came from. The inside of the float bowls appears to have corroded a bit but is probably workable. Of course the floats are shot, one has even been patched with JB Weld.

Included with the carbs were an extra set of lever-tops for the carbs. This is extra great because I was on the look out of a set to replace the banged up set on the current carbs.


He also had a pair of bar end turn signals for $50 so I picked those up even though I'm not sure I want to use them. One is new and unused, the other used and in need of a lens. Since they are $90 each new I figured I couldn't really lose.

These are one of my favorite parts of the /2. I just love how they blend into the design so cleanly.

Things didn't work out for me to get down to Olympia to crack open the transmission and deliver the vlave covers so I went ahead and shipped the covers and ordered the tools. They showed up on Wednesday and work a treat. gordonmessmer came over on Thursday and we pulled the transmission apart. All the gears look pretty darned good, including the kickstarter sector gear which frequently has bad wear on one end. I managed to knock out the seals but don't yet have the kickstart lever off. Once I get that done I'll take the casing to the local transmission shop for cleaning in their industrial wash.

Over the weekend I took a look at the rear brake shoes. I've got new brake compound for them so I drilled out the rivets and stripped off the old compound being careful to keep it went to prevent dust. Unfortunately what I found is really annoying. At some point in the past someone has replaced the brake compound but in doing so drilled out the holes that the rivets go through. Unfortunately this means that my rivets won't hold the new compound on. I've got a few options but I've not decided on which I want to use just yet. Ideally I'd get someone to weld up the holes so I could re-drill them to the right size.

I brought heads for the R50 to Kevin Brooks who went over what he could do for them. He's been doing some really interesting stuff with the engine on his "Bonita Rapide" 1955 R50. Most of the really interesting work has been done on the heads. He's lightened the valve train by 40% by replacing the valves with custom stainless steel valves with longer, thinner stems. The keepers are now made of titanium, and the springs have been lightened to suit. The results of this are less stress on the valve train and more room for air and fuel to get into the cylinder. It also looks so nice that it's a shame to cover it up. In theory I'll not only going have a more robust engine but I'll also have a bit more power too.

Next weekend I'll be heading down again. I'll be dropping off the valve covers for cleaning and I'll also be cracking open the transmission with Kevin's help. That's the last major component to be opened up. It really needs new seals and the bearings should be inspected.

In other news, the final drive is apparently on it's way back to me now. Things are really starting to come back together! Here's what's left to do:

• new seals and bearings for the transmission
  
• blast and paint the cylinders
  
• re-line the rear brake shoes
  
• bolt everything back together
  
• profit? hah!
  

gordonmessmer and I managed to remember to take pictures of the crank before we re-installed it. It's not much different, just a bit cleaner. It's most noticeable on the rods:

Yesterday I took the cylinders into a local shop, but they don't do the kind of blasting I need, nor the painting. Instead they referred me to a one of their sister companies that does. I'll have to find time to get out there during business hours. Maybe one morning next week.

Last night I packed up the final drive to ship out for a bearing replacement and re-shimming. I dropped it off at the post office after work today. Hopefully it won't be gone long.

I also mostly closed up the bottom end last night. I've still got to pound the oil pan back into shape but otherwise it's all back together. It looks like this again:


Next up for tearing apart is the transmission. I'm also going to have the heads cleaned up and reworked, but that's not something that I can do myself. I'm hoping to talk to an expert about it this weekend.

I got to hang out with some very cool people this weekend. I met up with cooncat, Morgan and Grant at the Ride West bike swap. I very nearly bought a totally sweet 1979 R65, black with white pinstripes. Fortunately for my bank account I deferred. It was a pretty sweet bike though. After the swap we went up to Capitol Hill for happy hour and just hung out and chatted. I definitely need to spend more time with those folks.

Part of our discussion was of course about the R50 and cooncat requested an update, so here it is!

I got the crankshaft back from Brent's Motor Works last week. It looks great and was essentially completely rebuilt. gordonmessmer came over and we spent an evening getting the crankcase back together. We were not as well organized this time and had to take the front bearing carrier off an extra time because we forgot the oil pump. We also forgot the oil splash ring so the crank had to come out again. In the end we got it all back together and everything seated properly. I'm glad that I sent the crank out because it's slightly shorter now which keeps the rear slinger from rubbing on the inside of the crankcase.

Then last night I heated up the flywheel (all 12 pounds of steel) and fit it on the end of the crank. The runout is just slightly over the limit at about 0.0045". I'm ready to call that good enough unless there's a fix that doesn't cost too much.

Tonight I sat down with the pistons, cylinders and my set of micrometers. The cylinders are dead on round with no taper. The pistons are as close to the exact same size as makes no difference. The wrist pins are pretty much perfect. The only thing that's possibly out of spec is the piston skirt to cylinder clearance. At the moment it's 0.006". The book says 0.0046" is the max, but I've got it on good authority that the book is being stupid. The pistons are aluminum and the cylinders are steel. It doesn't take too much heating up before you've used up that 0.0046 and are looking at a seized piston. I've got an email out to an expert asking his opinion. If he says they are too loose then I'll find someone to knurl the piston.

Tomorrow I may take the cylinders into a local shop to see about getting them cleaned up. They really need a good blasting and a lick of paint.

Pictures are still on the camera, I'll try to post them soon.

I finally packed up the crank and shipped it out to Brent for inspection and truing.

The final drive is also still in pieces while I figure out how to get the pinion needle bearing removed. It's pretty happy where it is but needs replacing. I want to get the final drive back together so I can start on the transmission.

Last weekend I got the crank out of the engine again and put aside all the engine parts on a tray. I've yet to pack it up but it will be headed out soon for rework. After that was all cleaned up I started looking for something else to work on. I momentarily considered disassembly of the transmission, but wisely left that alone for now. I tried removing the rear shocks for inspection but found that the caps had seized to the shafts which is something of a pain unless you have a special tool to assist getting them off. I then turned my attention to the final drive, which when we last saw it looked something like this:



I picked up the service manual and did a bit of reading. There were a number of special tools listed as being required. I then poked around on the internet and found that really you only need one. The others can be replaced with a blow torch, a piece of rope, a soda can[1] and careful application of several foot pounds of torque. So I ordered the tool for the final drive and the one for the shock cap removal.

A few days later I got the tools. Well, mostly. There was a bit of a mis-ship so I don't have the shock cap tool yet, but it'll get here soon.

To make a long story[2] short I now have the final drive mostly disassembled:



The only thing that I have left at this point is to remove the axle tube and inner seal. The good news is that everything looks to be in very good shape. The only potentially bad news is that proper reassembly requires a set of parallels and a depth micrometer, neither of which I own. If I can't find someone who a set of these that I can make use of then I will have to acquire a set. This isn't a job one should rush.

The information here about rebuilding the final drive has turned out to be extremely useful. None of my manuals actually tell you how to remove the axle tube so you can get at the inner seal.

[1]: Not kidding
[2]: Involving me balanced atop a contraption built out of among other things: the rear wheel, a tie-down strap and a breaker bar

I asked around on the /2 mailing list and got a few suggestions. I can either buy a crank balancing stand and a big hammer and true the crank myself, or I can do it right and send it off for a proper rebuild. Since the crank is already borderline in a couple of other areas I'm going to send it out. It's the core piece of the engine and if I'm going to rebuild this thing right I need to get the crank right. Either way I've got to take the engine apart again, which I might start on today.

I haven't done anything with the R50 in the last month. Discovering that the runout was out of spec kinda took the wind out of my sails. I finally got back to it today after discussing the issue with a coworker. I hadn't used any lube on the end of the crank, nor had I properly torqued down the flywheel bolt when I did the last test and we agreed that could factor into why I got the readings that I did.

So tonight I went back to it. I removed the flywheel and inspected the mating surfaces, then applied some moly grease and re-installed it. This is where the lesson in physics happened. The torque specification for the flywheel bolt is 150ft-lbs. I weight about 165lbs at the moment. The torque wrench is about 2 feet long. The distance from the center of the crank to the engine mounting bolts is less than 12 inches. The full repercussions of these facts were not immediately obvious to me. After attempting a few different positions I figured out that I could stand on the end of the engine mounting bolt and pull up on the torque wrench to attain the required torque specification.

Unfortunately even taking these steps did not solve the problem. The runout was still 0.012. I removed the flywheel again and rigged the dial indicator so that it rode on the flywheel mating surface at the end of the crank. Unfortunately this showed some lateral movement as I turned the crank. This is where the lesson in economics starts. I'm going to have to strip the engine down again and inspect the crank more closely. I may need to send it out for rebuilding which is not cheap and would blow the rest of my rebuilding budget. :(

So that I can end this post on a happy note: my brother gave me a most excellent christmas present. I unwrapped it and found a painted canvas. I had to stare at it for several seconds before I figured out what I was seeing. It looked very familiar and yet....



Click the image to see a high res scan as well as the answer to where the image comes from. It makes an excellent desktop picture.

I've done a bunch of little things to the R50's engine over the last week. It was but the work of a few minutes to repair the cam gear with a small file. The clearances are all good there now. I also installed the new bearing on the end of the crank and replaced the gear case cover. Then the seals went in, which meant removing the gear case cover again so I could get them seated properly. The bottom end is pretty much back together now.

I also dropped the cylinders and pistons in a bucket full of kerosene to try cleaning them up. A stiff wire brush was able to remove a lot of the gunk, though not all of it so they went back in for a couple of days. I need to see if they are further improved.

Tonight I installed the flywheel and tried checking the lateral runout. I'm fairly sure that I did things right, but unfortunately the runout is about 3x what it should be at 0.012, it should be less than 0.004. I'm going to have to see what can be done about that. Hopefully it does not require removing the crank again, that would rather frustrating having gotten this far. It could well be that I'm reading the gauge wrong.

gordonmessmer and I put most of the bottom end of the R50 back together on Saturday. We spent most of the time prepping things and waiting for the parts to either heat in the oven or cool in the freezer. The actual assembly took about 30 minutes. When bringing the parts together it was amusing to hear the sizzling as the frost on the cold parts boiled off on contact with the hot parts.

We made sure to take plenty of pictures this time. We didn't get every little step but you can pretty much see how it all goes together.

I love checking out the before and after shots:


Quite a difference!

Before I can close up the case I need to do some repairs to the cam timing gear. I managed to damage two of the teeth when I was trying to pull the gear off the camshaft. Nothing terrible, but those two teeth don't have the proper clearance now and will need to be dressed with a file.

Thanksgiving was pretty good. We went down to my parent's house and had dinner with them and my brother and his family. Jack is getting big and is still as cute as a button. Friday we went over to Julie's parent's house for dinner and they had a smoked turkey. It was amazing. I've found a new food to love. It was like a turkey that had been made of ham. I'm definitely going to try smoking my own one day.

I made fudge earlier this week. The first batch turned out ok, but the second was better. The only difference was how I handled the temperature control. I let the first batch cool down too much before stirring which resulted in the need for a lot of upper body strength to actually stir the stuff. Both batches were fun to make.

I finally ordered the parts for the R50 last week. New bearings, seals and gaskets all round. I also included a new rear main bearing holder since mine was borderline and it's the single hardest part to replace in the entire bike so I might as well do it now. Next weekend should see the bottom end going back together. Then I need to figure out what to do with the top end.

I drove down to see Kevin Brooks today. He took a look at the crank, cam, cylinders and pistons from the R50 and deemed them perfectly acceptable for re-use. I had planned on getting the cam re-plated and ground due to the small amount of pitting but Kevin said that it was best to leave it be as those pits will work as tiny oil reservoirs, protecting the lifters. That's fine by me as it means even less money spent. Kevin said that I just need to hone the cylinders and install new rings and I'm good to go. He said that one of the pistons had run extremely hot at one point which resulted in a bit of melting on one edge, but that it was still perfectly serviceable.

Kevin was also kind enough to make use of his oven (best shop accessory ever) and hydraulic press to press the cam gear off for me. I left the crank with him so he could replace the small end bushing on one of the rods.

Now I get to sit down and make a shopping list for all the little pieces that get replaced in the rebuild. Thanks to some advice from Kevin that'll be a little cheaper than I anticipated.

I got the bottom end torn apart today (see previous post about tools.) My dad came by this morning and helped with getting the cam out. The bolts holding it in were something else and required rather vigorous use of the impact driver (what a wonderful tool.) After that it was mostly just a matter of using different puller configurations until everything was apart. The slingers were full so that means that the crank really does need to come apart for inspection and cleaning. I was going to do it anyway so it's not a big deal. While the top end has been apart before the bottom end appears to be completely original. It's amazing how well it all worked for over 50 years with minimal maintenance.

Pictures here. Note the amount of crap that came out of the forward slinger. I haven't been able to look in the rear slinger yet but suspect that it'll be about the same.

I still find it amazing that the tolerances on this engine are so close that just heating the engine casing to 200 degrees (this takes longer than you'd think) will allow you to simply slide the bearings out. When cold there's no way you could pull them without damaging something.