BMW CAFE RACER R75/7

This is the BMW R75/7 Cafe racer build. Its been in progress for some time. I wanted to do the frame stiffening and the stiffened swing arm. The tank will be aluminum as well as the tail piece. I will be showing more on this build in a while.

side bracing turned out well-the sockets have internal tapers that seat on tapered bosses welded to the frame.

Final drive in place to add rigidity while I welded.

Tacked and ready for beads

DOM tubing, torch bent over a mandrel

Tank coming together, its quite large.

OUT OF THE SHOP

Philip is on a buisness trip, he's in a far away land, northern Jersey to be exact. He is peddling his wares as they say, "gone to market" might say others. So why is Philip writing in third person? Drama, simple as that. He is not in his shop where he can access photos and work on bikes and make postings of real metal bits being added to motorbikes, and he resents it. My friends, this will be an intellectual posting, when we set down our wrenches, we click off the Miller Synchrowave, and we reflect. Its time for some prose.

   The jacket is on already, the gloves are stuffed impossibly into a side pocket. The helmet is in the left hand and the keys are in the right. All time stops as the key is slid into the ignition switch. The kill switch is then flicked on and the starter button pushed. The engine fires, time starts again. As the bike warms up, we gear up. The air rich with hydrocarbons  as the machine is rolled out, and mounted. We are chambered and cocked, kick down, eyes up, and now clutch release. It begins...this dance we do, this song we sing, our bodies riding an impossible projectile traveling in our minds eye. Not only head but heart as well for our reference point. This exercise we move through has a cleansing effect, scrubbing away all but the essentials of the moment, such as braking and entry, apex and track out. Our attention riveted to road and target, the two hundred yard focus and glimpses of red line. Are we not space men? Are we not Cyclonauts drawn desperately to our type of space, the one in our minds, where we fly using our organic instrumentation  and the most spectacular invention...our beloved  motorbikes. Ride we say, fly... escape this world.

BMW CHOKES - The Blue Rat Drops A Valve

My '74 BMW R60/6  ...AKA The Blue Rat...dropped a valve due to badly worn valve guides. Learning curve...if you get a flat spot after 3000 RPM's it may not be the carbies. Here are some nice shots of the damage.









Very nice cratering of the piston crown!











Beautifully embedded valve tulip. Well done!








One cycle lift is not enough.

Bragging rights...got her down low enough to grind her heads! She's an old girl...but she puts out.
(yes I was scared)

HONDA CM400 CAFE BUILD-Steel Tailpiece

 The tail piece  is fabricated out of steel sheet. First card stock patterns were cut to lay it out on the sheet steel. I then made a run to my bud Jim at Marquise Auto Restorations to use the shear and box and pan break. The seat pan was done in one piece and the round tail, in two. One hour and the two tail sections were shaped on the english wheel, trimmed and ready to be tacked together. The seat pan was pretty much done on the break, I just needed to tack and weld the cuts. A hump had to be put in the front of the pan for some clearance for the frame, visible just behind the tank. Next the round tail and the seat pan were tacked in place and final welding was done. As a finishing touch, I ran the lower edge through a Pexto bead roller to stiffen the assembly and define the bottom of the tailpiece.

I wanted to slam the pan as low as I could against the frame, following the contour of the frame. So far Im ok with how it looks. Its coming together as a "look" with the modified tank. Right now I have an 18 inch rear wheel temporarily on there to make it a roller, and my brother says I gotta keep it. The CM400 had a 16 inch rear wheel which does look stupid in this case. so I will probably stick with the 18 inch rear. Tail lights are always in issue/decision with a cafe bike. Im really not sure what I'm going to do with this one. Possibly a little 2" red dot in a sheet metal cone contoured into the hump. but the hump has a beauty left naked. That's for a later day.

HONDA CM400 CAFE BUILD - Fuel Tank Modification

Sorry folks, I grabbed the whizzer before I grabbed the camera, so I don't have a before picture of the tank, but there were two styles on the CM400 and this was the type with the ridge on the top and not the tear drop cruiser tank. I believe these tanks were on the CM400T. I also believe the T stands for turd, but I'm not 100% certain. The plan was knee cutouts and a lower deck top with a weld in filler cap. First I stripped the paint with a super aggressive twisted wire brush on an angle grinder. I would say in the end it was as quick as using Tail Strip. Next, I whizzed the top off and made two circular cuts, and started to warp the surfaces into shape. and did some dent work. I then tacked in some scalloped shaped parts that I cut out and hammered up.





   Sorry I seem to work faster than I can photograph.  I cut a deck lid and gave it some shape on the english wheel. Cut the hole for the fuel cap and welded that in. Then zipped it shut. I just need to pressure test it now. Think I got pinholes? I"ll let you know how many later.


 





  Here is the tank on the frame ready for grinding, mud and sanding. Once the tank is in primer the shape will read much better.

HONDA CM400 CAFE BUILD - HOMEMADE CLIPONS

These are the clipons I machined for the project. They are pretty much just billet aluminum with holes punched in the right places and as much excess aluminum removed. Not sexy, but shop made. The aluminum is 7075. The real fun is making parts, not ordering them. Cutting metal and thinking through the process is a healthy endeavor, and much of what this blog is about.

HONDA CM400 CAFE BUILD - Frame Modifications

The bike was totally stripped and the frame modifications were the first order of business. First I cut the rear part of the frame off. These are often built up pressed metal components on UJMs. I wanted a cleaner more visible tube frame in the rear. This also gave me the opportunity to relocate the rear shock mounts to adjust the steering geometry. Raising the rear of the bike offers up less trail in the forks, and a little better handling in the turns.

I needed a set of new studs for the rear shock to frame mounting points. Two studs were turned out of 1" steel stock, and then a length of 1/2" square steel rod was tacked between the two studs to keep them in alignment.

I torch bent a tube forming the loop and cut two shorties making up the sub-frame. I fish mouthed the tubes and started to mock-up the layout.        








   

All the parts fitted and in place, Time to tack and lay beads.
















The finished frame modification. Yet to come are any mounting points , like battery box, tail piece mounts and turn signal mounts. These will come later as I start do the mock build and get all the components back on.