Small Updates

A couple small updates:

First, I forgot to mention that on my first real ride my son and I found this flag laying in the middle of the road at an intersection. I took it as a good omen.

Also, I didn't like having nothing on the sides of the starter cover - obviously I couldn't leave the R90/6 emblems on there though. Besides looking like it was missing something, the casting was really rough and I couldn't clean it up enough to remove the pits. So I got a later model starter cover - the one that's got "BMW" on the side, cut off the emblems, ground/sanded them down and then blasted them clean. I think I'll leave them unpainted as a nod to the original R50/2 engine.

And Done

I'm calling her done - although is that really a thing? I had three great 20 minute-ish rides but now I've got to check for intake leaks - all of a sudden my RPMs won't go down after I blip the throttle.

But, here's "done" pictures and a video. I gotta say, I've very pleased with the result:

First Start and Ride!

The video is a bit shaky, but you can't recreate first ignition and ride! I'll post some finished pictures and a video walk around this weekend.

I'm a little concerned about my charging circuit, but I think it's fine. I'll also do further testing this weekend.

Final Wiring Diagrams

Here are my final wiring diagrams that I used. Although they are fairly specific to my needs, they might be helpful to someone else. Wiring is oddly one of my favorite parts - I like the puzzle aspect to it. Feel free to post questions or comments regarding what I did.

I think most of it is fairly non-controversial, but I'll make 2 comments: (1) someone else might not have included all three relays on the same battery hot wire. My thought was that only one of the relays would be pulling current at a time since I'll start the bike with the lights off. Thus, I didn't think separate power wires were necessary; (2) Reg/rec instructions usually suggest that you hook up the wire that provides current from the reg/rec to the battery directly to the battery's positive terminal. I don't like to do that because I like a fuse between the battery and the reg/rec in case the reg/rec fails to do its job and causes a current spike that damages the battery. So that is why I attached the reg/rec feed wire after the fuse on the same wire that goes from the battery to the ignition switch. This leave my ignition switch unfused, but nothing else.

When I draw up my diagrams I like to put the components roughly in the spots where they are on the bike. Sometimes that creates some space issues, but by the time I realize it it's really to late to do anything about it. So, I'll live with my charging and ignition components kind of being scrunched up.

we're at 99%!

I am all but done with the project - I just ran out of time this weekend to finish up.

The wiring and cables are all installed and working properly (although I haven't tested the charging or ignition circuits).

I was originally going to use the stock points ignition so I had to make room for the Alpha electronic ignition but it worked out. In an ideal world I wouldn't want the ignition module under the tank, but space is limited. Likewise, I wouldn't want my reg/rec right behind the engine, but that's where it fit best.

I just have to fit the gas lines and line up the airbox snorkels - for some reason they're not lining up. I'm sure I put one of the boots on wrong or something. The petcocks should work, but I'll have angle them backwards, even on the right hand side.

I had to make about a 2" spacer to attach the horn so it cleared the front engine cover but didn't hit the front forks.

It turns out the /2 clutch cable has the same amount of exposed cable as the /6 cable, so I didn't have to cut it down like I thought I would. I used Tom Cutter's clutch cable instructions found here to adjust the cable. Ultimately, I used /2 brake and clutch cables since I'm using the /2 hand controls but I had to use /6 throttle cables so they would attach to the /6 carbs. I though I would have to modify one or more cables, but they all worked great.

I installed one of Vech's Brown style side stands. I had to heat it and bend it out a bit to get a better angle, but it seems to work well.

I got some stainless r69s mufflers from Keihan Systems in England. They were great to deal with and had my mufflers at my door in just over a week. I'm sure I'll never see my original mufflers from Epco - that was a very disappointing realization. Now we just have to get Keihan to start making conversion headers.

Hopefully my next post will be of a first start video!

Engine is in the Frame

I picked up my engine and immediately dropped it in the frame when I got home. It does look very nice.

With the transmission and all of the covers (including the deep oil pan) off, it went in without too much fuss. It did take me a couple minutes to realize that I had to tilt the rear of the engine upward in order to get the tranny back in position.

I shimmed the engine all the way to the right and still had to adjust the swingarm to the left of center a bit so that the driveshaft was in the middle of the swingarm housing. Hopefully that won't affect handling.

I've since ran the gauge cables (I needed to order throttle cables - I had new r50/2 cables, but they don't play nice with the R90 carbs. It also looks like I will have to modify the r50/2 clutch cable outer sleeve to work properly) and finished most of the remaining wiring. The rest of the wiring (and my completed wiring diagram) should be done this weekend.

I've all but given up on getting my mufflers from Tom at Epco. He doesn't seem to pick up the phone anymore. I've got some cheap Emgo mufflers I can use in the meantime. I was also disappointed to see that the crossover on the conversion headers he made me was significantly out of alignment. I managed to get them on, but I'll probably have to cut the crossover to ever get them off. Hopefully the misalignment doesn't cause leaks.

Almost there

Engine should be done today. Maybe I'll get a chance to slip it in the frame next weekend!

Engine work!

I worked with Tom Cutter for two days on my engine last week. I did all the cleaning and vapor blasting of parts while he did the disassembly and diagnosis. I still have the engine block and tranny housing to do, so I think I'll try to get back up there this week.

 Among the most painful issues found were: (1) one of the cylinders was rusted beyond honing (looking into nikasil plating), (2) the entire ignition system was hosed (will replace with an electronic unit); (3) one of the head covers was unrepairable (will replace with siebenrock racing repops)  and (4) kicker/tranny cover was cracked (he had an extra). The parts lists just keeps increasing and it's getting intimidating!

I opted not to get an aftermarket charging system, but we are upgrading to a later year that has a little more output. I also added an upgraded starter.