Topic: Marissa's 1972 CB500

[DaveBarbier]

Carbs look killer, hope the paint holds up! And dude, great sandcasting. Yeah, they’ll be weaker for sure but hopefully they’ll be ok. No idea though on that. And yeah, anodizing is very hard to get through.

[przjohn]

The Gold on The Kehin looks great. Lots of cool stuff going on with this build, keep up the great work!

[Godffery]

Dual disc conversion is awaiting front end reassembly, which is waiting for the triple tree to be painted and finished.

*Caution; Shameless self promotion dead ahead:*   
I can help you Pimp those Brakes if you'd like.  (lightened Rotors, Phenolic Pistons, Etc.)
 https://godfferysgarage.com/

[Marissa]

Dual disc conversion is awaiting front end reassembly, which is waiting for the triple tree to be painted and finished.

*Caution; Shameless self promotion dead ahead:*   
I can help you Pimp those Brakes if you'd like.  (lightened Rotors, Phenolic Pistons, Etc.)
 https://godfferysgarage.com/

Lol, these are your system! I bought them from Dave since he's now using a different front end.

[Godffery]

Oh, I see.  sorry, guess I didn't look close enough.
Are you running a stock Speedo or going electronic?

[Marissa]

I want to run a stock speedo! Will there be issues with running that?

[Godffery]

I want to run a stock speedo! Will there be issues with running that?

Possibility. Looking at the photo, It appears the mounting holes have not been counter-bored to recess the bolt heads. That could interfeer with the stock Speedo drive unit. 
 Like in this set:

https://godfferysgarage.com/wp-content/uploads/Xample-CB500-0009.jpg
 Here is a closeup:

https://godfferysgarage.com/wp-content/uploads/Hon-450-500-550.jpg

 If the Rotor bolts are from a GL1000, (with the low profile heads) then they might clear, but if so, just barely.

[MauiK3]

Yamiya carries low profile bolts for 750's, not sure if they are the same and would work on yours.

[DaveBarbier]

I want to run a stock speedo! Will there be issues with running that?

Possibility. Looking at the photo, It appears the mounting holes have not been counter-bored to recess the bolt heads. That could interfeer with the stock Speedo drive unit. 
 Like in this set:

https://godfferysgarage.com/wp-content/uploads/Xample-CB500-0009.jpg
 Here is a closeup:

https://godfferysgarage.com/wp-content/uploads/Hon-450-500-550.jpg

 If the Rotor bolts are from a GL1000, (with the low profile heads) then they might clear, but if so, just barely.

Those bolts will work fine as this was all installed before and fit wasn’t an issue. But, Marissa, you will need to either modify your current speedo drive or buy the already modified one from Godferry. As you can see, the roll pin holes are already drilled for it.

[Register]

Terrific explanation of what to look out for on


http://blacksquaremotorcycle.com/dual-disc-conversion/


110mm bolts should clear the speedo drive fine, Works in my mock-up.

Most of the issues relate to spacing the caliper to suit the disc alignment.

Calipers in front or behind?

[Marissa]

I want to run a stock speedo! Will there be issues with running that?

Possibility. Looking at the photo, It appears the mounting holes have not been counter-bored to recess the bolt heads. That could interfeer with the stock Speedo drive unit. 
 Like in this set:

https://godfferysgarage.com/wp-content/uploads/Xample-CB500-0009.jpg
 Here is a closeup:

https://godfferysgarage.com/wp-content/uploads/Hon-450-500-550.jpg

 If the Rotor bolts are from a GL1000, (with the low profile heads) then they might clear, but if so, just barely.

Those bolts will work fine as this was all installed before and fit wasn’t an issue. But, Marissa, you will need to either modify your current speedo drive or buy the already modified one from Godferry. As you can see, the roll pin holes are already drilled for it.

Terrific explanation of what to look out for on


http://blacksquaremotorcycle.com/dual-disc-conversion/


110mm bolts should clear the speedo drive fine, Works in my mock-up.

Most of the issues relate to spacing the caliper to suit the disc alignment.

Calipers in front or behind?

Not gonna lie, kinda lost on what needs to be modified about the retainer. Everything looks fine, is the retainer just pushing the bolts out?

I'm attaching photos of everything as of current to help give a perspective:

[Godffery]

That tin cover is eliminated, and the Speedo drive recesses slightly into the rotor center.

https://godfferysgarage.com/wp-content/uploads/Xample-CB500-0009.jpg

[Marissa]

That tin cover is eliminated, and the Speedo drive recesses slightly into the rotor center.

https://godfferysgarage.com/wp-content/uploads/Xample-CB500-0009.jpg

I'm not sure I understand why though, haha. The tin plate (at least, with how it's set up currently) doesn't affect placement of the speedometer at all, as the speedo seats on a piece inside, not the tin plate. If I cut the tin plate there's no way of mounting it to anything. Is the point of cutting it to make the OD of it fit inside the disc and help "seal" the speedometer backing since the o ring is removed?

[DaveBarbier]

Does the wheel fit inside the forks?

[DaveBarbier]

I believe the speedo needs to sit inside the rotor against the new modified speedo drive plate since you’re adding the thickness of an additional rotor.

[Godffery]

The Speedo drive will not seat fully with the tin plate on.

[Register]

As you have things at the moment, everything outside the new disc is spaced off further than originally.

The speedo drive won't engage and the wheel won't seat correctly in the forks - spindle bolts up too wide.

You will need to trim the speedo drive plate to fit inside the new disc centre and pin it to prevent rotation.

Then omit the cover plate.

Should work fine as long as you shim the calipers to suit fork sleeve mounting.

[Bankerdanny]

Here is the modified drive for the twin disk conversion on my 750F and the drive seated on the wheel. Ignore the two carved out sections of the rotor center that look like tabs. That was from a bad attempt to adapt the stock drive that I haven't fixed yet.

[Register]

As the previous post, the only bits you need are the drive plate and the speedo ‘gearbox’.

If you fit as attached photo everything is spaced too wide.

You need to cut the shoulder off the drive plate, as the previous post and then fix it with a short dowel or similar to the hub.

The drive plate rotates with the wheel, the gearbox stays still.

[Marissa]

Thanks for the pictures guys, definitely have a clear idea now. Dave, I see the roll pins now. Too bad I used my current hub for the assembly...

For now, I'm just going to run single disc until I have time to modify everything else. I'm pushing to get the bike on the road for right around end of May. Realistically it's smart to start with single disc and see if I wanna upgrade after I get comfortable with this set up.

Front end is together but waiting for top triple tree to come back from paint. Wiring has to be redone when that comes together.
Found out my master cylinder set up won't clear with clip ons, so I'm going to have to order something. I personally hate the rectangular shaped master cylinders, especially with the style going on my bike. They just scream 80's. Maybe I'll get the Nissin Retro styled one off Dime City, it would be smart to get a good brand instead of my current reproduction one.

Carbs are almost done being put back together. I got glass bead, however it looks like I'm not using enough material and I think I could use more air (Think I have a 5 gal tank and just 25lbs of glass bead)? So media blasting took painfully long. I decided just to wire brush hardware gently without removing the old chromate plating and reassembling the carbs like that. I will still plate some pieces but not nearly as many as I planned. Oh well!

It's really hard to capture good shots with this lighting lol.







Making a nicer room for the CB to live in too

[DaveBarbier]

I have the Nissin Retro master cylinder and I like it a lot. 14mm for me works well for single disk and dual disk. Even with my dual 4 piston caliper R6 front end.

Space is looking good. Hope you get the bike up and running soon, I’d be down for a ride.

[Marissa]

I have the Nissin Retro master cylinder and I like it a lot. 14mm for me works well for single disk and dual disk. Even with my dual 4 piston caliper R6 front end.

Space is looking good. Hope you get the bike up and running soon, I’d be down for a ride.

Any chance you can measure it out Dave? I have very little room to work with haha.

[SF]

Carbs look friggn brilliant


Sent from my iPhone using Tapatalk

[DaveBarbier]

I have the Nissin Retro master cylinder and I like it a lot. 14mm for me works well for single disk and dual disk. Even with my dual 4 piston caliper R6 front end.

Space is looking good. Hope you get the bike up and running soon, I’d be down for a ride.

Any chance you can measure it out Dave? I have very little room to work with haha.

Sure, I’ll do that when I get out in the shop. So it’s just the space the actual perch takes up? I’ll just give you a handful of measurements. My concern was that the clipon clamp was too bulky so I wouldn’t be able to slide the master cylinder up all the way on the bars. But my clipons are pretty low profile and I can get the master cylinder up right against the clamp.

[DaveBarbier]

The perch width is just over 1” maybe by a 1/16”. The back side of the perch, like the clamp part that you screw onto it sticks out about 1/2” off the bar. The reservoir sits about 1/4” away from the bar. Like there’s a gap enough where I can slide my mirror right up in there.




Are you worried about any specific part interfering?