Author Topic: $100 1978 Cb750 project (Read 6137 times)

Rydog400f · « **on:** June 24, 2017, 07:38:20 AM »

Picked up this little gem from a friend. Motor was seized and it was missing the title. A little over a week of marvel mystery oil and the cylinders freed up with ease and a little schmoozing at the dmv brought the $610 late fees and penalties down to $400. Thinking about just bringing it back to stock but am kind of leaning towards a gl1000/ '76cb750 spoked wheel conversion. I'm pretty sure this year came with a painted engine which is chipped pretty bad. Other than that I changed the oil, plugs, battery, and cleaned the carbs and it fired up! Easiest project bike I've started in a while!

Sent from my HTC6545LVW using Tapatalk

firebane · « **Reply #1 on:** June 24, 2017, 08:10:08 AM »

As I mentioned in another area you have a F model bike which are a bit more sought after.

SOHC4 Cafe Racer Fan · « **Reply #2 on:** June 24, 2017, 06:07:19 PM »

The F models had black painted engines.

The F1/F2 have comstars and probably the best CB750 SOHC4 brakes. The GL will give you slightly more stopping power and 37mm (versus 35mm) diameter fork tubes. You will need to do a complete swap though -- triples, forks, brakes, wheel, rotors, etc. If you were swapping from a K model, I might recommend it, but here I don't really think the juice is worth the squeeze.

Rydog400f · « **Reply #3 on:** June 25, 2017, 08:10:29 AM »

Quote from: SOHC4 Cafe Racer Fan on June 24, 2017, 06:07:19 PM

The F models had black painted engines.

The F1/F2 have comstars and probably the best CB750 SOHC4 brakes. The GL will give you slightly more stopping power and 37mm (versus 35mm) diameter fork tubes. You will need to do a complete swap though -- triples, forks, brakes, wheel, rotors, etc. If you were swapping from a K model, I might recommend it, but here I don't really think the juice is worth the squeeze.

Yeah after doing more research I think I've decided not to do the swap and really just bring it back to stock with the vfr brake upgrade.

Sent from my HTC6545LVW using Tapatalk

Rydog400f · « **Reply #4 on:** July 08, 2017, 05:22:04 PM »

Got some more work done today and had a LOT of parts come in. I bought what I though was cb900f front and rear brakes. But it looks like the front is for a 900c and the rear is a cb900f. The 900c won't fit the 750f mounts. Got a new headlight and some other bits. Tank is being prepped for por15 now. I'm also having trouble finding a 22mm petcock. Any help is much appreciated!

Sent from my HTC6545LVW using Tapatalk

madmtnmotors · « **Reply #5 on:** July 08, 2017, 05:57:13 PM »

Aftermarket fuel valve (scroll down):

http://www.vintagecb750.com/products/6/fuel-system/67/fuel-petcocks-gas-tank-caps-and-parts

Fitment is determined by measuring the OD and thread pitch of the threaded bung on the bottom of the tank. Be sure to pull the old filter out of the bottom of the tank from inside the petcock bung. New filter can still be had from Honda:

http://www.hondapartsnation.com/oemparts/p/honda/16952-388-015/screen-set-fuel-strainer

How much do you want for the old petcock?

SOHC4 Cafe Racer Fan · « **Reply #6 on:** July 08, 2017, 06:13:41 PM »

That's a bummer about the front calipers. I imagine the dual piston 900f calipers should improve the stopping power. Hopefully the seller will take back the wrong calipers.

Those rotors could use a little TLC, too. I wouldn't ride on those shocks either. I'm looking forward to seeing you bringing this one back.

SOHC4 Cafe Racer Fan · « **Reply #7 on:** July 08, 2017, 06:15:00 PM »

Quote from: firebane on June 24, 2017, 08:10:08 AM

As I mentioned in another area you have a F model bike which are a bit more sought after.

It's funny because 10 years ago, that wasn't the case in California.

Rydog400f · « **Reply #8 on:** July 08, 2017, 06:35:33 PM »

Quote from: SOHC4 Cafe Racer Fan on July 08, 2017, 06:13:41 PM

That's a bummer about the front calipers. I imagine the dual piston 900f calipers should improve the stopping power. Hopefully the seller will take back the wrong calipers.

Those rotors could use a little TLC, too. I wouldn't ride on those shocks either. I'm looking forward to seeing you bringing this one back.

I hope I can just find the 900f brackets and bolt them on. Oh yeah I wasn't planning on riding it with the rotors/ shocks this way. Rotors will get honed and drilled and ordering some hagons shocks.

Sent from my HTC6545LVW using Tapatalk

Stev-o · « **Reply #9 on:** July 08, 2017, 07:25:23 PM »

Subscribed. You have a name for this bike yet?

seanbarney41 · « **Reply #10 on:** July 08, 2017, 11:16:45 PM »

Quote from: SOHC4 Cafe Racer Fan on July 08, 2017, 06:15:00 PM

Quote from: firebane on June 24, 2017, 08:10:08 AM
As I mentioned in another area you have a F model bike which are a bit more sought after.

It's funny because 10 years ago, that wasn't the case in California.

I dont think that is the case anywhere... its funny because f parts are precious, but the whole bike aint worth #$%*. Don't get me wrong, I love the F's, you just cant sell em.

Terry in Australia · « **Reply #11 on:** July 09, 2017, 04:11:11 AM »

Wow, that brings back memories. I bought an F2 like yours for $400 on ebay 12 or 13 years ago and spent a small fortune restoring it. Thanks to Photobucket holding my pics hostage, I can't show you a before and after pic now, but it looked better than new when I'd finished. It was a great bike when I finished it, but as has been said before, they're worth nothing compared to early "K" series bikes, and I lost several thousand dollars when I sold it. Great bikes, but I'd never restore another one. Cheers, Terry.

SOHC4 Cafe Racer Fan · « **Reply #12 on:** July 09, 2017, 09:09:05 AM »

Quote from: Terry in Australia on July 09, 2017, 04:11:11 AM

Wow, that brings back memories. I bought an F2 like yours for $400 on ebay 12 or 13 years ago and spent a small fortune restoring it. Thanks to Photobucket holding my pics hostage, I can't show you a before and after pic now, but it looked better than new when I'd finished. It was a great bike when I finished it, but as has been said before, they're worth nothing compared to early "K" series bikes, and I lost several thousand dollars when I sold it. Great bikes, but I'd never restore another one. Cheers, Terry.

I thought that was still the case, but I have never tried to buy or sell one.

MauiK3 · « **Reply #13 on:** July 09, 2017, 09:26:43 AM »

I'm glad I'm not thinking about selling my K3 when I'm done. If I added up the costs there would be no way to break even. These bikes are expensive to bring back. I still have some pretty pricy things to get such as calipers, maybe a master cylinder, various nuts and bolts, pistons and I assume valve guides. Oh, I also will be getting progressive fork springs and shocks. It adds up quickly. If I were to sell it someone would want to buy it for what it sold for in 1973. Do it for the joy, not the money. Only a very few vehicles make money. I suppose if someone had a very low number K0 it might bring in real cash. I'll just enjoy putting around with my wife as other "guys of a certain age" look at me and wonder where the bike came from and dream of their youth. :-))

Rydog400f · « **Reply #14 on:** July 09, 2017, 01:09:33 PM »

Quote from: MauiK3 on July 09, 2017, 09:26:43 AM

I'm glad I'm not thinking about selling my K3 when I'm done. If I added up the costs there would be no way to break even. These bikes are expensive to bring back. I still have some pretty pricy things to get such as calipers, maybe a master cylinder, various nuts and bolts, pistons and I assume valve guides. Oh, I also will be getting progressive fork springs and shocks. It adds up quickly. If I were to sell it someone would want to buy it for what it sold for in 1973. Do it for the joy, not the money. Only a very few vehicles make money. I suppose if someone had a very low number K0 it might bring in real cash. I'll just enjoy putting around with my wife as other "guys of a certain age" look at me and wonder where the bike came from and dream of their youth. :-))

That's how I feel too. I've never really built a bike to make money. If I'm lucky I'll make a few hundred. After the first one the money just gets recycled from one to the other.

Sent from my HTC6545LVW using Tapatalk

Rydog400f · « **Reply #15 on:** July 09, 2017, 01:13:09 PM »

Quote from: madmtnmotors on July 08, 2017, 05:57:13 PM

Aftermarket fuel valve (scroll down):

http://www.vintagecb750.com/products/6/fuel-system/67/fuel-petcocks-gas-tank-caps-and-parts

Fitment is determined by measuring the OD and thread pitch of the threaded bung on the bottom of the tank. Be sure to pull the old filter out of the bottom of the tank from inside the petcock bung. New filter can still be had from Honda:

http://www.hondapartsnation.com/oemparts/p/honda/16952-388-015/screen-set-fuel-strainer

How much do you want for the old petcock?

Well I guess I'll keep it. The bike had a full tank when I got it and it wasn't leaking. I think I'll just try to replace the rubber washer and reuse it. Thanks for the link!

Sent from my HTC6545LVW using Tapatalk

madmtnmotors · « **Reply #16 on:** July 09, 2017, 03:16:04 PM »

Quote from: Rydog400f on July 09, 2017, 01:13:09 PM

Well I guess I'll keep it. The bike had a full tank when I got it and it wasn't leaking. I think I'll just try to replace the rubber washer and reuse it. Thanks for the link!

The new strainer/filter comes with a new gasket for the petcock. Be sure to get all of the old gasket out.

Rydog400f · « **Reply #17 on:** July 16, 2017, 06:02:38 PM »

Got the front brakes sorted. Picked up a pair from an '85 honda shadow for $25 and they bolted right on. Plus they're in way better shape than the original! Almost ready to tear the bike down for powder coating. Just trying to figure out what kind of seat to go with. My wife and I decided it would be a single seat. I've been trying to find something that would allow me to use the stock hinge and seat lock. Also looking into the handle bar setup. I have some super motos on now but like the look of the Hyde m bars.

Sent from my HTC6545LVW using Tapatalk

SOHC4 Cafe Racer Fan · « **Reply #18 on:** July 16, 2017, 07:58:13 PM »

Another member converted his 2-up Super Sport to a single. The build currently escapes me, but it use the stock hinges as well.

Rydog400f · « **Reply #19 on:** July 16, 2017, 08:02:31 PM »

Quote from: SOHC4 Cafe Racer Fan on July 16, 2017, 07:58:13 PM

Another member converted his 2-up Super Sport to a single. The build currently escapes me, but it use the stock hinges as well.

I've seen a few. I think the Corbin seat is Bolt on.

Sent from my HTC6545LVW using Tapatalk

Farley121 · « **Reply #20 on:** July 17, 2017, 07:26:44 PM »

IIRC, Carpy has a fiberglass cafe seat that used the the original seat hardware.

Geeto67 · « **Reply #21 on:** July 18, 2017, 10:04:45 AM »

Quote from: Rydog400f on July 16, 2017, 06:02:38 PM

Just trying to figure out what kind of seat to go with. My wife and I decided it would be a single seat. I've been trying to find something that would allow me to use the stock hinge and seat lock.

If you can find one, Giuliari made a special seat for the F model supersports in the 70's/80's that used the stock hinges and locks. they are a bit wild looking and rare as hens teeth but they are out there and you can find them:

Rydog400f · « **Reply #22 on:** July 18, 2017, 11:12:39 AM »

Quote from: Geeto67 on July 18, 2017, 10:04:45 AM

Quote from: Rydog400f on July 16, 2017, 06:02:38 PM
Just trying to figure out what kind of seat to go with. My wife and I decided it would be a single seat. I've been trying to find something that would allow me to use the stock hinge and seat lock.

If you can find one, Giuliari made a special seat for the F model supersports in the 70's/80's that used the stock hinges and locks. they are a bit wild looking and rare as hens teeth but they are out there and you can find them:

Woah!

Sent from my HTC6545LVW using Tapatalk

SOHC4 Cafe Racer Fan · « **Reply #23 on:** July 18, 2017, 11:14:17 AM »

Quote from: Geeto67 on July 18, 2017, 10:04:45 AM

Quote from: Rydog400f on July 16, 2017, 06:02:38 PM
Just trying to figure out what kind of seat to go with. My wife and I decided it would be a single seat. I've been trying to find something that would allow me to use the stock hinge and seat lock.

If you can find one, Giuliari made a special seat for the F model supersports in the 70's/80's that used the stock hinges and locks. they are a bit wild looking and rare as hens teeth but they are out there and you can find them:

If that's wild looking, it's definitely wild looking in a GOOD way!! Very cool, although I'd avoid white as the upholstery.

Stev-o · « **Reply #24 on:** July 18, 2017, 01:51:47 PM »

Quote from: SOHC4 Cafe Racer Fan on July 18, 2017, 11:14:17 AM

Quote from: Geeto67 on July 18, 2017, 10:04:45 AM
Quote from: Rydog400f on July 16, 2017, 06:02:38 PM
Just trying to figure out what kind of seat to go with. My wife and I decided it would be a single seat. I've been trying to find something that would allow me to use the stock hinge and seat lock.

If you can find one, Giuliari made a special seat for the F model supersports in the 70's/80's that used the stock hinges and locks. they are a bit wild looking and rare as hens teeth but they are out there and you can find them:

Very cool, although I'd avoid white as the upholstery.

Better than some of the other ugly colors I've seen

News:

Author Topic: $100 1978 Cb750 project (Read 6137 times)