Topic: Good Lord where do I start? CB750... ish

[754]

 I will think about some kind of sidecover for the electrics..
are you going to run a rack and sides to hold up the bags ?

[Killman]

I've thought about racks, but I'd have to wait until I have the exhaust mocked up to see the necessary clearances. Might just put some small brass grommets in the lower back of the bags for tie-downs. The bags sit okay where I've got them, but it's not really practical as is, and when the bobbed fender and shorter tail light go on, they're not going to work that great underseat with the shocks. Thinking I could at least use them until I can make some up myself. Should only take a year or so to get my leatherworking skills up to speed. 

Not really enthusiastic about the idea of using hard bags. Like to be able to just grab the bags off the bike when I'm at a hotel or campground.

[SOHC4 Cafe Racer Fan]

Yeah, that seat looks terrific.  Make sure you have some bracing to keep those saddlebags from getting close to the spokes.  Looks like a fun cruiser.

[Killman]

Came across this pic today. Looks promising 

[Killman]

Wow, time sure flies! This project got shelved for a bit, but it's time is once again nigh. I just had a quick re-read of the thread so far and was really happy at all of the great advice you guys had shared. It looks like I found solutions to pretty much all of my earlier questions and the end result is going to be so much better for your help. It would take a small book to describe all of the improvements that have been incorporated, so I'll just go with huge thanks to all of you guys!

Sadly, it turned out that the frame had some damage. Both down tubes up front were dented and bent. Tough to see until I had the engine out and felt the frame carefully by hand, actually had to hold some white paper behind it to see the damage clearly, but a straight edge confirmed the crappy news. I've got the frame in with a local guy who gives me two options, pay him at least a grand to fab up a jig and do the repairs, or go the quick and dirty route of a few hundred bucks to knock the downtubes straight. If I can't lay hands on a straight frame by next week, quick and dirty it shall be. If it handles like a drunk monkey afterwards I can take it to a guy up-island who's already tooled up for these and pay him a buttload, or just pay the nice man here his money. It'll be what it'll be.

I was hoping to have the project ready for this Summer so a few months ago I tried to save some time by handing the engine off for a rebuild to a local guru with a pedigree racing and building the CB's. Unfortunately the engine work never got finished and I'm heading up-island to pick up my parts this weekend, along with some other bits for a rear disc conversion.

So, more questions.

First up, looks like there's been some kind of changes to Photobucket, how do you guys share pics on the forum now?

Second. Regarding a conversion to rear disc. The parts I'm possibly grabbing this weekend look to include a small section of subframe with a rear mc and spline attached, as well as a swingarm with topside brake mount. Seller believes the parts came from a '75 CB750F. Now besides a replacement spoked rear disc wheel, what other replacement bits might I be forgetting? Anyone know offhand what years/models of wheel will work for my application and will the change mess up the offset for my rear sprocket? Any pitfalls I should be aware of?

TIA

[754]

 I should have  A 77/78 F SWINGARM AND probably  brake and pedal but no 78 rear mc . I do have 75 or 76 rear mc.
 A lot of folks go to other master cylinders .
 I don't think its a bad  idea to go to a late swingarm, its wider and about 1 1/4 inch longer. Even if you don't run wider wheel it will be there should you want it.
 I think 75 76 F stuff is harder to find than the late stuff .

[calj737]

Sadly, it turned out that the frame had some damage. Both down tubes up front were dented and bent. Tough to see until I had the engine out and felt the frame carefully by hand, actually had to hold some white paper behind it to see the damage clearly, but a straight edge confirmed the crappy news. I've got the frame in with a local guy who gives me two options, pay him at least a grand to fab up a jig and do the repairs, or go the quick and dirty route of a few hundred bucks to knock the downtubes straight. If I can't lay hands on a straight frame by next week, quick and dirty it shall be. If it handles like a drunk monkey afterwards I can take it to a guy up-island who's already tooled up for these and pay him a buttload, or just pay the nice man here his money. It'll be what it'll be.

FFS! A $1,000!!?? Geez, I’d almost drive up there, fix it, then drive it back to you for that much dough. 

Willing to post some clear, and accurate pictures of the damage? Might be other “solutions” to your dilemma. You can use Flickr, Imgur, or simply attach them inline to your thread.

[Killman]

So, it looks like I have a new frame lined up, from the guy I had left my engine with. It's a '75 F, with papers, and I'll have the swingarm, both mc's and rear caliper. So disc brakes all around, which is nice. Hopefully I can use all of my parts from the '72. If not then I have a line on another frame closer to home that might work.

Got back the engine and spare parts last week. I'll be doing the rebuild myself now, which should be interesting as I've never had one of these apart before. It runs, but the oil pressure is at 70 and it's smoking like crazy from all four cylinders. Starting to feel kind of bummed out about this project, hopefully my enthusiasm comes back as I make some actual progress.

I'm attaching some pics of the '72 frame that I took during teardown.

[Killman]

Hey guys, I've got a question for you. I've been doing some digging to make sure that 1975CB750F frame will work with my 1972 CB750k parts and it's not looking good. From what I can see my tank is an inch too short and a bunch of my other parts won't fit either. Oil tank, seat, both stands, etc. If anyone knows offhand if these incompatibilities are correct, could you chime in? TIA

[754]

 I have a cheap oil tank   but you side covers won't fit. Your side stand can be extended, tank can work.
Probably less hassle to deal with than setting your 72 up for rear disc.

[Killman]

Yeah, I decided I didn't want to have to modify or replace half my parts, so I turned down the F frame. Had a line on a guy from Langley, with a couple of frames, but no papers for either. There's another unpapered frame locally that I can pick up for cheap if I have to go that route. So basically I'm stalled out again, until I can hopefully find an early papered K frame.

Frame on the brain.

[754]

 Are you going disc on rear or not..?

[Killman]

Maybe, it would be a nice mod and I've got most of the parts I'd need for it, but it's not going to ruin my day to just move on with the rear drum. Priority for now is to find a good titled K frame.

[Killman]

All right, back to work on this beast! Guess I should update.

Tore down the wheels today, so the hubs can go in for powder coating with the frame. Rims are pretty banged up and rusty, thinking new ones are the way to go. Frame is straightened and the frame kit is installed.

Got a running engine, (that in theory has a big bore kit, no idea on size) that's going in for walnut blasting this week, to take off the old rattle can that's on it. Then I'll put some new rattle can on it.  Bunch of stuff going in for plating as well. Once all of that cosmetic stuff is done, it'll be time to put everything back together.

[Killman]

The frame and hubs should be back from powder coating within the next week. Also managed to finally find what seems to be the only guy on the Island that blasts with soda, so I should have the engine back within the next week as well.

I'll be stripping paint from the fuel and oil tanks in the meantime, so I can send them in for plating with the front fender once I get it mocked up and modified for size and fitment. Did a bike last Summer where I copper plated the fuel tank and front fender, looking to go with brass on this one. Wanted to brass plate the rims as well, but they sent me chromed ones, and my local plater says they wouldn't fit in his tank anyways. Kinda bummed about that, but oh well. Still undecided about plating the engine covers, thinking it might just be too much, sometimes less is better.

Looks like Canadian Tire is going to be putting an engine stand on sale this weekend, (http://www.canadiantire.ca/en/pdp/maximum-engine-stand-1000-lbs-0090223p.html) thinking it would make painting the engine much easier. Anyone have any ideas about how to modify that thing so that I could use it to hold the CB engine for painting?

[Killman]

Got the frame and hubs back from powder coating, and the engine back from soda blasting, last week and they all look great! Wish I remembered how to post pics on here. Going to spend the day lacing the hubs to the new chrome rims, maybe even tape off the engine for painting too, if time allows. Using Black Pearl for the fins and Titanium Blue Silver for the crankcase, engine covers will be polished, think it's going to look pretty trick when it's done.

It would be awesome if I had a roller by the end of the week!

[Killman]

Well, got the wheels laced today and they sure do look purty! Plan for tomorrow is to pressure wash the engine, drive the bearings into the hubs and true the wheels while the engine dries, then with any luck I'll have time to tape off and paint the engine and drop the wheels off to have the new tires installed on the way to my night job.

Other chores for the week as time allows, polish my fork lowers, front fender, triples and engine covers and build my forks. With any luck I can scrounge up someone to give me a hand getting the engine back into the frame on Saturday and then it's full speed ahead to get this thing together!

[Killman]

Success, I have pics!

So here's the engine nowadays. The cam cover was pitted and peeling like crazy, so I didn't bother taping it off. I was originally going to go with black for the fins, but the silver laid on so bright and clean that I just stuck with it. Think it's going to be tits with the replacement chromed/polished engine covers.

[Killman]

And here's the frame and wheels. Bit of a piss-off with the powdercoat, when I went to install the bearings in the front hub, I found pc in the retainer threads. Chasing the threads and installing the retainer caused the pc to crack and flake away from the surrounding hub surface. I already had the wheels laced and didn't want to have to break it down again, so I'm going to have to figure out some sort of cosmetic fix, depending on how noticeable it is when the wheel's installed.

The dude in the pic is the guy that shot the powder. It's really pretty stuff, doesn't show properly in the pics, but it's a metallic 2 coat set-up, so it's an iridescent brassy green and changes color in the light.

[calj737]

Next time, you can very carefully use a product like Aircraft Stripper with a Q-tip and brush it on the threads, let it soften or remove the PC, then use a thread chaser to remove the PC without damaging the area.

Sorry this comes a bit late 

[SOHC4 Cafe Racer Fan]

Next time, you can very carefully use a product like Aircraft Stripper with a Q-tip and brush it on the threads, let it soften or remove the PC, then use a thread chaser to remove the PC without damaging the area.

Sorry this comes a bit late 

Cal endorses the careful use of strippers.

[calj737]

Next time, you can very carefully use a product like Aircraft Stripper with a Q-tip and brush it on the threads, let it soften or remove the PC, then use a thread chaser to remove the PC without damaging the area.

Sorry this comes a bit late 

Always use care with Strippers. You never know when an NDA is in your future.   
Cal endorses the careful use of strippers.

[Godffery]

Came across this pic today. Looks promising 

Holly Crap...! I think I know where that photo was taken?  That looks very much like a place I use to ride dirt bikes when I was Young & indestructible.

[754]

 You grew up in Canada ? Or along the border ?
 The helmet makes me think Canada.
 My buddy who weighed about 150 lbs, used to ride his like that, once I  a while..

[Godffery]

You grew up in Canada ? Or along the border ?
 The helmet makes me think Canada.
 My buddy who weighed about 150 lbs, used to ride his like that, once I  a while..

Not IN Canada but close, Wisconsin USA.