Topic: My first 750: '76 CB750F

[Bankerdanny]

I used my new master cylinder to push out the pistons from my F3 calipers. They are shiny and free of pitting, so next week they get a nice cleaning and new seals and should be ready to go on the bike along with the front Lester and freshly thinned and drilled rotors.

I thought you were going to do the twin-piston caliper upgrade?

Maybe eventually. Right now I am going to stick with stock. I've spent quite a bit more than I intended and still need to buy paint. the twin piston calipers may be next year's update.

[Bankerdanny]

Slow progress continues to be made. Today was all about the wheels and brakes.

The F3 got a good cleaning and fresh piston seals. The pistons themselves were in great shape with no pitting.

A couple weeks ago I sent 3 brake rotors to Godffrey for thinning and drilling, 2 550 fronts and one rear. Scottly recalled that the 550 rotors would work with the F3 forks and calipers and Lester front wheel for my twin disk conversion. They are definitely the same diameter as the ones on the Comstar front. We should know for sure in a couple weeks.

I installed the rotors on the wheel, but first modified the right side rotor to hold the F3 speedo drive. I had to mess up the freshly painted center of the rotor, but you can't tell unless you get down and look really closely.

I pulled off the rear Lester I had installed last weekend, polished up the outer rim, installed the rotor, and back on the bike.

I also took time to take pictures of the wire wheel drive flange and the Comstar flange side-by-side. If you look you can see the obvious differences.

[Bankerdanny]

Here are the drive flanges. The one on the left is the wire wheel and the one on the right is from the Comstar.

[scottly]

Danny, the speedo drive plate needs to be underneath the rotor hub, not on top of it. You need to cut the recesses on the back side of the hub, and the plate should be trimmed so it fits loosely through the center hole. The rotor hub basically replaces the stock thin chrome plated drive retainer. 

[Godffery]

 This modification will do the job best.
https://godfferysgarage.com/wp-content/uploads/z-Mod-Speedo-Plate-280.jpg

[Bankerdanny]

Danny, the speedo drive plate needs to be underneath the rotor hub, not on top of it. You need to cut the recesses on the back side of the hub, and the plate should be trimmed so it fits loosely through the center hole. The rotor hub basically replaces the stock thin chrome plated drive retainer.

Hmm, that's annoying. I should have done better research. I was thinking the spacing was a little different. This may slow down the conversion slightly. Fortunately I have the original single disk from the 750 I can send to Godffrey to have the carrier section modified for use with the rotor I already have.

[seanbarney41]

Danny, get the kit pictured above by goddfrey.  It's really cheap and easy.

[seanbarney41]

Do you have spacers to line up your 550 rotors with the f3 calipers?

[Bankerdanny]

Do you have spacers to line up your 550 rotors with the f3 calipers?

No. I figured I would have to sort that out once the fork legs were swapped.

[scottly]

This is how I was doing the speedo drive:

[Bankerdanny]

This is how I was doing the speedo drive:

Basically the opposite of what I did.

[Don R]

 I looked on the bucket for pics of hen I did my 76F but they must be on the old floppy discs from the modern digital camera. lol.

[Bankerdanny]

I didn't think that I would be able to work on the bike this weekend, but it turned out my Sunday was free so I was able to enjoy a warm Spring day and open the garage door and work on the bike.

Yesterday I removed the exhaust so I could use my bike jack to lift it off the ground and remove the front wheel and swap the stock fork legs out for the F3 legs. I also needed to paint the bracket I made for the muffler and the small adapter I made for the replacement rear master cylinder I installed last summer.

With the fork legs swapped I confirmed what Scottly had told me that the wheel wouldn't fit with the speedometer drive on top of the rotor the way I had it. So with some help from my brother-in-law, a cutoff wheel, and a bench grinder, I cut down the drive to fit under the rotor, problem solved. I haven't decided yet if I am going to install roll pins the way Godffrey does. Right now I am thinking yes; they may not be 100% needed, but they are a "belt and suspenders' approach to make sure the drive stays fixed.

The next step was to work on the spacing of the caliper brackets. I only had time to work on the left side, but I think I got it. I measure, but I tried a variety of washer combinations and found one where the rotor appears to be well centered in the slot on the bracket. Next week I need to do the same thing for the right side.

Finally, I installed my weldless frame kit from Frank and Scottly that I got last summer. I didn't necessarily need it (which is why I have had it for almost a year already without installing), but as long as I am doing all these projected I thought I would knock this one out too.

[Bankerdanny]

Fixed my out of round front tire (installation issue) and checked the balance on the stand I picked up at Harbor Freight today. Its livable, but I'll pick up weights tomorrow to get it perfect.

I also installed new fork seals today. I am debating repainting the lowers before I reassemble. I've put so much effort into it it seems stupid to not make everything as nice as I can

[Bankerdanny]

Good progress this weekend, but still didn't finish the mechanical.

- I drilled and installed 2 roll pins like what Godffrey does with his kit to make sure the speedometer drive flange doesn't move.
- Balanced the front wheel.
- repainted the center of the right side rotor center where I had gouged out a pockets in my early attempt to adapt the drive flange.
- Installed new fork seals and fluid and reinstalled the forks.
- Sorted the spacing for the caliper brackets and installed the calipers.
- Swapped the front master cylinder and mocked up the lines.
- Made up a bracket for the brake line splitter. The dual brake splitter won't just bolt up to the '76 lower where its splitter went. I had some spare aluminum around the garage I was able to repurpose.
- I replaced one of the headlight shell bolts that had gone missing and painted up the shell.
- Replaced the burnt out bulb in my right rear turn signal.

[Bankerdanny]

I ordered all new front brake lines earlier this week that are scheduled to be delivered tomorrow. So Sunday I should be able to get the brakes sorted and be done with the mechanical portion of the Spring upgrades. I decided to try these: https://www.ebay.com/itm/Venhill-Braided-Brake-Line-Kit-6-32-Inches-Long-Banjo-Fittings-No-Bolts/112908770674?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

They are braided stainless that use an AN type fitting with screw on banjos, so I should be able to get the clocking of the eyes perfect for the MC I bought, an 80's style square with the exit on the back rather than the end like the original. The original fouls a bit on the gauges because of the lower bars with a slightly narrower center.

Next will be paint.

[Godffery]

 Just a heads up; The Banjo ends on Core Moto lines can swivel to allow for exact clocking.   https://www.coremoto.com/
https://www.coremoto.com/

[Bankerdanny]

Just a heads up; The Banjo ends on Core Moto lines can swivel to allow for exact clocking.   https://www.coremoto.com/
https://www.coremoto.com/

Those look like the same lines I have coming. I'll post pictures once I have them in hand.

[Medyo Bastos]

Looking good. These are what I use ->






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[Bankerdanny]

Looking good. These are what I use ->






Sent from my iPhone using Tapatalk

Nice. Do the tabs on the bottom fit into the existing voids on the hub?

[Bankerdanny]

Well, I didn't get my new front brake setup completed as planned because USPS screwed me (shocking I know). My lines were on track for Saturday delivery until about 1:30 PM when the status changed to "delayed", which is what it still says. Hopefully that doesn't mean lost.

While I am waiting I did have other work to do. So the headset bearings got properly tightened, the center stand spring installed, and the paint stripped off the tank and filler applied over a couple of small dents.

Next Sunday should see fully functional front brakes and a prepped and primed tank ready for paint as soon as I settle on a color. I want to have it back on the road before the end of May to put some miles on it before heading up to Kalamazoo June 7-8 for the Gilmore Classic Bike Show then off to the Carolinas and Mid-Ohio Vintage MC Days at the end of June/beginning of July.

[Medyo Bastos]

Looking good. These are what I use ->






Sent from my iPhone using Tapatalk

Nice. Do the tabs on the bottom fit into the existing voids on the hub?

Yes, they do


Sent from my iPhone using Tapatalk

[Bankerdanny]

I got notice yesterday that my brake lines were finally delivered, so this Sunday should be the last of the mechanical work for this year.

Today I finally ordered the paint. I agonized over what to buy, the color, the style (metallic, pearl, flake, candy etc), do I want to try and paint the stripes on the side, is there any other detail I'd like to add, a rally stripe down the center of the tank and the tail, white checkerboard, ghost checkerboard?

When I bought it my bike was a bad rattle can metallic blue. I know from sanding the original tank down that was originally the fairly rare Sulfur Yellow, I color I like well enough, but it just doesn't pop for me. I really love the Flake Sunrise Orange from the F0 (here's a picture of SeanBarney's spectacular F0), but at the same time I wanted something original.

So for the past couple months I have been looking at shades of copper from various sources, I watched bunches of videos of different painters on techniques for painting flake and pearl. Then I happened to randomly search for Roth (as in Big Daddy) Flake, and found the company's website and line of can based paints, which seem perfect for the small project of painting the tank and tail. They also have some YouTube videos of how to do the job using a MC tank as an example.

So today I went back, hemmed and hawed about color options, and settled on a kit in a color they call Bad Azzz Blue.  My order won't arrive until sometime next week, but hopefully by the end of the weekend of the 24-25 the paint will be done.

[BigJimG]

The lighter version of that color looks similar to a metallic version of Candy Sapphire Blue.  (at least on my screen)

[Bankerdanny]

The lighter version of that color looks similar to a metallic version of Candy Sapphire Blue.  (at least on my screen)

Yes it does. I'll be looking for the darker blue as my primary color