My old welder went to work for Apple… the nerve of him! Instead of molding metal, he is now working with Jony Ive designing high end plastic components to contribute to the distractions and communications of the universe. Oh well… we all need to expand our career horizons.
I got connected with a new welder and the guy is an artist! Just like the last bike, we filled the holes on the rear main frame tab, added a permanent boss for the rear sets, and reinforced the bottom corner that always cracks. He went crazy and boxed it in. It looks amazing and that rear area will never flex again.
I am glad I am doing a complete rebuild of this bike. The steering was a bit stiff and not smooth. Once I got the neck out of the frame, I realized why.
Rusted Steering bearings.
Since the frame is going to be powder coated, the races have to come out anyway. I could see somebody buying the bike and not getting this deep into the restoration and it would be dangerous to ride with bearings like that.
These went straight to the trash.
These piston and cylinder kits seem to be the rage right now. I used one on the last build and had very little problems aside from the pushrod seals being extremely difficult to install.
The pistons are made to mate with the R75/5 heads and you can use the same carbs (might need to change jetting).
Here is a quick look at the piston and how it compares to a stock R75/5 piston that i have lying around.
I haven’t heard of any issues with these yet. Supposedly they give you a 20% gain in power… so that makes it around 900cc.
I’m pretty sure they are cheaper then replacement BMW parts too.
It really helps to have friends with amazing machinery.
In this case, it is my first time using a Maho milling machine.
I learned the basics and was able to use it to drill out the rivets for this worn rear wheel spline.
Although it could be done as an entire wheel, I de-laced the hub and it was much easier to handle. The hub will will get powder coated and new bearings, spokes and rim anyway.
Here are the various attachments. One was for making a center punch style hole, the other was to drill out the rivet.
There is so much prep work to do that never gets seen for the final bike.
I spent 4 days lining this gas tank to be used for the next build.
The first step of the POR 15, “Marine Clean” is one you have to be careful of.
You can use old petcocks or get corks to stuff into the fuel taps to seal them off.
The hard part is sealing off the gas cap area.
You don’t want to spill this stuff on a tank that you are not painting on the outside!!!
It will leave a stain on the paint.
This tank will get some body work done to it and re-painted so I wasn’t too concerned when some “Marine Clean” spilled out of the gas cap area.
This takes a good amount of sloshing around to clean the tank at least 20 minutes.
Then you need to empty the tank and rinse it thoroughly with water.
Day 2 –
The “Metal Ready” is the second step and it will remove the rust and prep the metal for the paint to stick to it.
This step requires that you leave the fluid on each side of the tank for about 20-30 minutes.
You then need to completely dry the tank.
Day 3 – an extra day in the sun and a few rounds with a heat gun to let the tank dry.
Day 4 – ugg… the Sealer…
A messy process. You have to mix it well, pour it in and then turn the tank in every direction so the goopy paint has covered every part of the tank. If it spills, clean it immediately.
Then carefully pour all the excess paint out. I find that I end up using about 1/2 of the can that comes with the kit.
If you have 2 tanks, or a friend’s tank, you might be able to get two tanks done for the price of one!
This breaks my heart every time I do this…. but it’s gotta be done.
This fender has been kicking around my garage for years from an old parts bike. It has some rubber paint on it so it has been preserved really well, but it is something I would never use on a restoration. It is ugly and the work needed to remove the rubber coating and restore it isn’t worth the trouble. It kills me to cut a solid fender up but I need a donor fender and this one was lowest on my totem pole.
The piece I will make will get trimmed down from this but the first cut hurts the most.
And, the bike I am building came with a set of /5 headlight ears without reflector holes. A rare breed. It saves me the trouble of trying to source a set. But cutting a set breaks my heart. It’s gotta be done for the upper triple plate modification.