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

[Killman]

The PO's seem to have welded a tab over the original tank bolt hole. Anyone care to share a pic of their stock frame in this location so that I can use it as a guide as I try to cut off the added piece?

[Stev-o]

Tank bolt? You sure about that??

[Killman]

Nope, but it's dodgy looking welding, (matches the relocated hinges on the seat pan) and I'd like to get a look at an original frame to see what it should look like.

[Stev-o]

Post a pic of the area you at describing.

[754]

 When you were talking custom sidecover did you mean electrics side only, or oil bucket side as well ?

[Killman]

Just electric

[Killman]

Here's a few pics of the area of the frame that I was talking about.

[seanbarney41]

the thing with the prongs is original, the thing with the bolt hole is definitely not

[Killman]

Thanks, that's what I figured. Anyone have a picture of a stock frame I can use as a guide when I take it off?

[seanbarney41]

You are gonna need the rubber cushion that goes there.  Get a new one from Honda.  Once you have it on hand, its easy to see ho it works.  Sorry, I don't have any pics.

[Killman]

I've got the rubbers. Just want to make sure I don't take too much off the top.

[SOHC4 Cafe Racer Fan]

Just grind off the weld attaching that tab to the piece with the prongs, which needs to stay.

[Killman]

Sounds like a plan. Just like to make sure before I start trimming bits

[Killman]

May as well post some pics of a little mock-up of some bits I did the other day to lift my spirits. Wanted to at least see what the new tank, seat, front fender and saddlebags would look like. Put on the place-holder stocker shocks I picked up for now, just to raise the ass up a bit. I'll be using the taller Konis for the real thing. Nothing's actually properly attached at this point, pulled them all off, except for the shocks, and re-crated them afterwards.
Been too busy with work to do much wrenching. Trying to clear some computer and bookkeeping stuff off my plate so I can get on with things. Hoping to run the frame, wheels and exhaust up-Island next weekend for some powder and ceramic.

The overcast really made that chrome look good in the pics. In person it's all pretty wretched. lol

[Bootsey]

I dig that seat, where's that from? Are you sticking with the ape style bars?

[Killman]

Thanks. Had the seat made custom by the Vietnamese guy in Socal on EBay. Looks pretty, but it took two months, and was a PITA the whole way. Looks like I'll be needing to peel back the cover and foam to mount hinges as well. Hoping it lays down as nice the second time.

Hopefully swapping out a set of 60's Tomasselli tracker style bars for the apes. There's a pic of them a few pages back in the thread, I think. If they don't work out, I've got a nice vintage set of Renthals I can throw a brace on.

[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 .

[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.