Topic: Another '75 CB750F Project

[Milkman666]

Well, I picked up this ol' girl about 3 weeks ago now, for $500. She didn't run when I got her, but after the usual troubleshooting routine I got her going.

I plan to make this a(nother) cafe racer... eventually. I have a new baby around so I don't have as much time as I'd like, so hopefully next summer I'll have her on the road again.

Here she is as I got her (with 17,000 miles on the clock):



Note the 4 clamps holding the universal muffler on! I took care of that today. I added a Supertrapp that I had laying around, and she sounds pretty good with it on there. True, it's meant to be on the other side of the bike, but it'll work out just fine. I'll zap off the bracket when I get a chance and hold it there with a stainless strap I think. I could probably use the bracket with some creative bending... hmmmmm.

[cafeconleche]

Looks like the bike is in good condition.

Good luck, can't wait to see the outcome.

[dieselndixie]

awesome!  have fun.  I am working on a 75 cb750f as well.  i will be watching this.

mine so far...
http://forums.sohc4.net/index.php?topic=47398.0

[Milkman666]

Ahhh, yes. I've been watching your build as well. Keep up the good work.

[Lee in Ottawa]

Nice Bike. I've been looking for a local bike recently. Where did you find this one? Any chance you know os any others?

[Milkman666]

So here's the plan for attaching the fiberglass tail section I'll make in the future. I used this system for an '86 GSXR streetfighter project once and it worked well.

First I got the latch/release mechanism from a '98 Suzuki GSF 1200S Bandit complete with the cable and key. I had this one lying around, but you can get 'em used pretty easily. Suzuki used this type of latch on MANY bikes, so it's easy to find. This latch works well because it's very wide and has two pins to support and hold the seat unit in place.

The first hiccup (maybe) is that I have to order the "striker", which is the piece that attaches to the seat. I hope I can simply order this from Suzuki with no trouble, but if you've ever owned a Suzuki you know I'm nervous about this.

Here's a pic of the parts. I will need part #11 to complete this.



I hope to mount the latch mechanism (part #5) on the frame cross piece behind the battery box, put the striker in it a mock up the seat/tail unit using foam, etc., and 'glass it up. Then I will bolt and fiberglass the striker into the seat unit to keep it there nice and solid. Then I will 'glass up a seat pan with integral bolts that will protrude through the seat unit and bolt from underneath.

Does any of this make sense? It worked on the Gixxer!

[DollarBill]

Your starting off with a nice looking bike.  Can't wait to see what you do with it.  I have a 75 F too and have gone from the cafe idea to a more semi-modern cafe-street fighter look. http://forums.sohc4.net/index.php?topic=41900.0

I'll be watching your build.  Good luck!

[Do0ki3 PWNS]

wow! looks real nice.

[Milkman666]

Well, it's getting chilly outside so I finally had a few minutes to spend with the ol' girl.

I popped off the tank and gave it a good look inside. It looks great! No real rust at all, just some slight discolouration. A big relief.

I then proceded to wedge the engine in the frame on the way out! I tried the lay it down and lift the frame off method but it all went sideways on me when I got all excited and tried to remove the power plant before removing the chain (first of several bonehead moves to come, I imagine).

Oh well, I'll try to get it out of there again tonight.

This bike is in very good shape. The more I tear into her, the more I realize that I got a very sweet deal here.

[Slayer]

The bike looks nice, I am going to have to follow this one.

[Milkman666]

Well, hopefully life has finished, or at least slowed down with the curveballs for now. The bikes been sitting in my garage for quite some time in a state of partial disassembly, but I'm ready to get back at it.

First up is the swingarm. I was gonna send it to Hondaman, but the shipping is killer from here, and I've discovered that all the bits and bobs are in pretty good shape. I've ordered some bronze bushings, and picked up a brake cylinder hone at Princess Auto for $8.

I'll set the bushings in the swingarm, then measure them and hone them round/to size as required to match the collar with .008" clearance

I'm gonna cut grease grooves in a spiral pattern along the whole length of the collar (as recommended in Hondaman's book), then create a slight groove at the point where the grease enters to help it get into the system.

I have no choice now, with babies in the house, but to work late at night, so I aplogize to all my co-workers in advance for my general bad humour.

[Milkman666]

Well, I got the swingarm bushings out using a washer that I smashed into an oval shape so it could be inserted into the tube, then driving them out with my B.F.S. (Big Screwdriver)

I also started cutting the spiral grooves in the collar as outlined by Hondaman in his book. I don't know if I'll post pics... mine are nowhere near as pretty as Hondaman's! I had to stop cutting the grooves because of a crying baby. I have decided that she will not be going for a ride on my CB 750.

[Milkman666]

I got the swingarm all prepped and ready for bushings; now I just have to wait for them to arrive.

Got the front end off tonight... pretty smooth sailing. Everything looks real good on this bike, even where problems are expected; swingarm was well lubed and nice looking, and same with the steering head; all well greased and no visible signs of distress. Waiting for tapered bearings to arrive too. Should I put the races in before powder coating the frame, or after? I couldn't knock the races out yet because of sleeping babies, so I'll put it on the weekend agenda.

That's it, pics to follow.

[immortal]

Great looking project you have there,  Good luck with it!

[Milkman666]

Thanks immortal.

I went out to look at her tonight to get ready for some seat action. I'm very excited for a couple of reasons; first, my method of attaching the seat using the Gixxer seat hardware mentioned and pictured above really looks like it will work well, and second, I put the tank on to see where the seat would line up and took another peek inside - it looks marvelous in there! I have a fibre optic camera at work. I'm gonna send it in there and look around; I'll try to take pictures somehow.

[Milkman666]

Like many of you out there, I was faced with the decision of how to attach my cafe seat unit... velcro?... screws?... zip ties?... duct tape?

Well, like many of you out there I have quite a few parts of bikes past laying around my house, and while I was basking in the glory of my milk crate of '86 GSXR parts, I saw it... the seat hardware. It looked perfect! I finally got around to installing it today.

The firt picture is a shot of the striker mechanism (on the bike) and the latch (in my hand).

The rearward holes of the striker did not land far enough under the frame cross member to allow me to drill holes for bolts to pass through, so I ground away a portion of the cross member (see second pic) with the idea of welding or bolting a plate in there, but as it turns out, I don't need it. the frame cross member bears almost all of the weight, so the two screws holding the striker should be plenty.

The third pic shows the latch engaged with the striker. Now I just have to attach the latch to my seat unit and I should have it!

If you're interested the hardware came off a 1986 GSXR-750, but Suzuki used these parts on several of their bikes (and maybe ATVs too). They're all over eBay.

The release cable will be run along the frame rail toward the front of the bike and simply held in place using zip ties or clamps. It's very easy to release and doesn't take much pressure, but I'll probably fashion some sort of pull-ring on there.

[Milkman666]

It's official; the engine has left the frame! It's on the engine stand now (thanks to the Tips and Tricks section here).

Only a couple of snags really. First, one of the little studs that hold the breather cover got bent. I'm really hoping this isn't a big deal. The shifter mechanism got disengaged too, and I'm totally in the dark about how it's supposed to go back together right now. I guess I'll have some homework to do.

I'm tired. Good night.

[Milkman666]

Got the steering bearing races out. Easy-peasy.

Also got the shifter mechanism figured out... not the most complex problem in the world!

Next steps: remove VIN plate, grind off seat bracket and hinge, disassemble wheels and generally get ready for powder coating.

[Milkman666]

VIN plate is off, with some damage. Making the plate out of tissue paper was definitely a poor decision.

The unnecessary seat hardware is gone too.

The bad news is that the rockers were all pooched:



Then, after removing the camshaft, I discovered that the lobes were all crapped out as well. I put a straightedge across them and shone a light behind, which let me see the little tiny mountain range profile, where there should be a nice flat plain. Oh well, new cam. I guess I'll just have to lift 'em a little higher and a little longer.

My theory is that the bike sat for a long period of time at some point, and the top end dried out and got crusty, then someone fired her up and messed up all the rockers/cam.

[Milkman666]

Yeah Baby! Seat unit arrived today from Twinline Motorcycles (http://new.twinlinemotorcycles.com).

[Milkman666]

Resurrection.

It''s been a long while. My kids are getting bigger (and stronger)  now, and I hope to have some more time to dedicate to this.

I started installing the "Gordon" frame kit I purchased from member 754. Should be all ready for welding this week. I don't weld, and while I'd like to try, this is not the time or the project.

I have started learning to paint while I've been away, so I'll get some paint and try to shoot the frame myself. I'm a stubborn ol' boot, so I'll probably try to do the tank and other stuff too.

Anyway, I'm still here, and still plugging away.

[SOHC4 Cafe Racer Fan]

Yeah Baby! Seat unit arrived today from Twinline Motorcycles (http://new.twinlinemotorcycles.com).

That's a great looking seat from Ian!