Author Topic: 76 Supersport (Read 17218 times)

Don R · « **Reply #25 on:** January 10, 2014, 09:37:36 PM »

I like your style. That's how I like to do things.

frodef2 · « **Reply #26 on:** January 13, 2014, 12:01:09 PM »

small update with some milling done to the triple tree I'm gonna use on the 750.

The stem is extended at the bottom with 11mm. A plug was machined in a lathe, and pressed in and welded.

The upper tree had to be machined down 9mm at the stem area to be the same thickness as the stock cb750 tree. I just wish i had found a upper triple that i can fit a regular steering bar. I guess i will have to create some risers, or buy a new triple.

Also the bearings for the wheel axle arrived, stock cb750 outer diameter and 25mm inner diameter. perfect fit for the ducati axle.

frodef2 · « **Reply #27 on:** January 14, 2014, 12:30:34 PM »

Update with the assembled front fork and tree.

Now i have to start taking measurements for the wheel spacers.
The new axle is 25mm, so i cant use the old ones.

frodef2 · « **Reply #28 on:** January 23, 2014, 11:03:38 AM »

More front fork mockup.
I am unable to find the bolts for the callipers. They are 10mm fine tread pitch. The old honda triple tree bolts had the correct pitch, but where too long.
So i added lots of washers.

mockup spacer.
Since the ducati axle already has the spacer built in on the right side, the spacer is only 11 mm thick.

Other side.
as you might see, the caliper is disassembled,because it rubs the spokes.

I will machine down the surface where the caliper meets the fork leg. This will give me 5 mm more spoke clearance.

Temporary brake disc spacer.
I have drawn a spacer in autocad that is 15,4mm wide at the brake disk. It also has a centering edge suited to the ducati disc. The Honda disc has a 60mm hole, and this is 64.
Luck is that the ducati disc has the same bolt circle as the CB (6x80mm)

Spacer autocad drawing.
I will source some material and make this on a lathe maybe this weekend.

70CB750 · « **Reply #29 on:** January 23, 2014, 11:23:10 AM »

Nice!

frodef2 · « **Reply #30 on:** January 26, 2014, 05:36:01 AM »

I've been asked to describe a bit closer on how i shortened the seat pan.

I did not take that many pictures while i was doing the shortening, so i hope this helps.

This first picture shows how much shorter the new pan is.
I took a measurement from the vertical part of the seat with the red cowl to the end of the frame.

This is the measurement that you need to cut from the pan.

I do not have pictures of the pan parts before i tacked them together, but this picture shows, a bit what how i cut the pan.
In this pitcure the pan is only tacked together on the sides.
As you may or may not see, the hinge brackets are left in place, i cut around them. as shown in a later picture.
i do not have a picture of the uncut pan, but when you see it, the shape i cut the rear part of the pan should make sense.
The front part of the pan needed some hammering to get the metal to meet up with the rear part.

The next picture show the hinge with the metal supports i made.
sorry for the poor picture quality. Low lighting and shallow DOF. + some shaking.

The supports were welded in after i had welded the 2 halves together.

another picture of the same.
I should change how this support structure is welded together, since removing, and reassembling the plastic rear bit. Is already a pain without the seatcover. This area needs to be wider.

Picture of the lock side.
More hen dropping welds.

When all is done, it should look like this

Frode

SOHC4 Cafe Racer Fan · « **Reply #31 on:** January 26, 2014, 08:28:29 AM »

Really great job of shortening the seat, while keeping the functionality of the hinges. Nicely done!

frodef2 · « **Reply #32 on:** January 31, 2014, 01:07:33 PM »

small update.

I got a new disc for the front wheel. The disc i used for mocking up the build was almost worn out. The new disc was sourced from my local Ducati dealer. Originaly from a 996SPS.
This disc is almost 2mm thicker than the old rotor.

I also got new brake calliper bolts from the same dealer. As you can see here, its all assembled

This picture shows the spoke clearance. the disc spacer is also visible in the lower part of the picture.

Next step is to try to make the stock speedo drive work with a 30mm axle.
Wish me luck

martin99 · « **Reply #33 on:** January 31, 2014, 01:57:17 PM »

With the skills and eye for detail you've got mate you won't need luck. Good job.

Enjoying this one (planning on some seat surgery myself tomorrow). Keep them pics coming!

frodef2 · « **Reply #34 on:** February 07, 2014, 01:50:20 PM »

Small update.

Installed the fork on the bike. I'm not happy with the look. The old lowered fork looked better i think. Maybe i just need time to let it settle in my head.

Since i have even more Ducati parts laying around, i will try to mate the rear disc from the sportclassic with the center of the stock cb750 f1 brake disc.

This is the clearance between the calliper and the disc center. i will turn the center down 2 mm to be sure.

SF · « **Reply #35 on:** February 08, 2014, 03:41:55 PM »

Can we see the bars on? Or you using clipons? The forks are really beefy compared to the tank

frodef2 · « **Reply #36 on:** February 09, 2014, 12:23:19 AM »

I don't have the bar risers ready at the moment, and i am still considering clipons.
I have looked all over ebay, and have not found any risers i like.

frodef2 · « **Reply #37 on:** February 14, 2014, 02:11:19 PM »

I got some bad engine news today.

A while back i took the engine apart to do some performance enhancements together with a general overhaul.

Crank bearings showed only some small discoloration on some of the shells. but today i pulled the rods and the rod bearings ....

This is the worst one. Rod number 2

The rod journal also has some scarring on number 2.

I guess i have to pull the crank from the spare engine and pray it is ok.

frode

Jerry Rxman Griffin aka MuthaF'er · « **Reply #38 on:** February 14, 2014, 03:59:21 PM »

Send the crank to Big Jay @ APE and have it lightened and balanced. He'll take care of that slight journal issue at the same time.

frodef2 · « **Reply #39 on:** March 01, 2014, 11:05:00 AM »

Small update with the rear brakes.

I had to use a calliper hanger that has the calliper under the swingarm.
the first hanger i got placed the caliper right where the shock is mounted.
The caliper bracket started its life as a ducati part, so i had to make a bushing. i made the bushing out of center to be able to avoid interference with the brake disc.

Testfitting. The disc is a stock ducati monster disc, where i machined off the mounting tabs in a lathe. then i mounted it in the stock brakedisc center.

Here it is on the bike. I still need to mill the hanger width down 2 mm to center the wheel in the frame.

In this picture the brand name of the ducati brake bracket is visible. You can also the the bolt used to lock it in place.
This will be welded and grinded so it should not be visible when its done.

70CB750 · « **Reply #40 on:** March 01, 2014, 12:13:15 PM »

Looks sweet and I like the excentric bushing. But are you comfortable with the brake caliper udner the swingarm? I know I wouldn't be.

calj737 · « **Reply #41 on:** March 01, 2014, 12:51:29 PM »

70CB - I've heard others mention the position of calipers being a concern. It seems strange to me as I see lots of different bikes where the calipers are "behind" forks, or some where the caliper is under the rotor.

If you don't mind, can you expound on the issue? Perhaps I'm not the only one who doesn't realize the issues involved.

Thanks in advance-

Apology for a slight hijack...

70CB750 · « **Reply #42 on:** March 01, 2014, 12:58:22 PM »

Mainly dirt and water from the road, the caliper will not like it. I cant recall a vehicle now that does not have caliper in the upper half of the disc, can you?

Secondary, and that would not be me, lean it far enough to scrape the caliper, but that would take some serious knee dragger.

calj737 · « **Reply #43 on:** March 01, 2014, 01:12:08 PM »

So if I correctly understand you, you're citing only environmental abuse (or possible conflict under sever lean angles). The reason I asked was I've heard others caution about the position (front forks) of the location of the caliper ahead or behind the fork leg. Thought you might be referencing a similar issue regarding the rear placement (over/under).

Your point is well made, thanks for the clarification.

Retro Rocket · « **Reply #44 on:** March 01, 2014, 01:56:11 PM »

Quote from: 70CB750 on March 01, 2014, 12:13:15 PM

Looks sweet and I like the excentric bushing. But are you comfortable with the brake caliper udner the swingarm? I know I wouldn't be.

Since the early 80's and the advent of the GSXR's FZR's and the like, nearly every sport bike built had or has an under slung rear caliper, thats 30 years of bikes, some of the latest model bikes have gone back to a top mounted caliper but thats more to do with swingarm shape than anything else. I wouldn't worry at all about a bottom mounted caliper or clearance issues, its not a problem.... A lot of newer bikes still have under slung calipers, just look at the Kawasaki Z1000, Ducati 899 panigale, and Suzuki GS1200s, for instance, there's plenty more.....

70CB750 · « **Reply #45 on:** March 01, 2014, 02:08:54 PM »

Thanks, I knew they exist, I justdont know them.

calj737 · « **Reply #46 on:** March 01, 2014, 04:35:50 PM »

Not to belabor a point, but Retro do you have insight on the front fork caliper position issue that I've encountered? For instance, when I attempted to relocate the caliper on my 550 behind the fork, I was discouraged by many from doing this. They gave no substantive explanation, and in the end my custom fender brackets made it unfeasible. But I can't understand why there would be a difference.

Retro Rocket · « **Reply #47 on:** March 02, 2014, 03:32:24 AM »

I've never had the smaller Honda's and don't know if there are any differences in the brakes, I've had 20 odd 750's and most of them had twin discs and Ive had them both with the calipers at the rear and front, unfortunately all 3 750's i have at the moment i got incomplete and all 3 will be sporting different front ends {2x43mm, 1x41mm}with late model rear mounted brake calipers so i have nothing to compare with.... Dave500 knows the 500-550's inside out, he may be a better person to ask...

Actually, come to think of it I am sure we used to just reverse the front end and modify brake lines and guards to suit....

Hon3ybadger · « **Reply #48 on:** April 12, 2014, 02:28:38 AM »

Brilliant idea on the "Cafe'd" F seat! I'm sure many people will think it came from the factory like that. I'm going to replicate that design on my 76F.

Don R · « **Reply #49 on:** April 14, 2014, 10:43:52 PM »

Reversing the fender is as simple as drilling the rivets, swap the fender around and reinstall with some stainless steel button head bolts. At least on a 750.

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Author Topic: 76 Supersport (Read 17218 times)