74 CB750 Project: Reassembly Help

[Nightviper19]

Howdy,

Like title says, I got a 74 CB750 Four K. I got this bike from a friend, and it is in several boxes and pieces as the picture shows. I did not take it apart, and Im not familiar with older bikes since the oldest bike I own is a 2001 ZR-7S. Therefore, its kinda difficult to find out where all the bolts and nuts and washers go, especially since they are all in a ziplock bag, not sorted in the slightest. Any help would be appreciated, like pictures of rebuilds and such. Im sure I'll get stuck somewhere along the line.

Right now, I just got the frame blasted and painted, and got all the chrome (Except for the stock tail pipes) back to looking very shiny. Next up is cleaning the tank, and replacing the clutch and head gasket.

Thanks in advance. I've restored a 70 Ford Mustang, 90 Yamaha Radian, and used to work at a bike shop, so Im not exactly new to the work, just having trouble putting bolts in the right places and finding the right place for a bracket to go, etc.

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[Re-run]

Well good luck there.
You will want to get a manual. Dont even bother without one. There are so many different torque specs used that it will kill ya. Get a honda shop manual, the 71-76 should do just fine. If you have to get a different one, get 2, a haynes, clymer, or chilton. None of them cover it all like the honda one does.

[combat]

trial and error good luck with it

[combat]

forget clymer and chiltons they are a waste of money go for factory manual they can be found on ebay for a reasonable price

[Nightviper19]

So where would I begin? Does the engine go in first? I did a compression test, checked/replaced all neccesary gaskets, and made sure the motor turns over and does what its supposed to do. I got everything prepped to go back on, but should I put the suspension and wheels back on to get the frame up in the air, or what?

[Re-run]

Get the wheels on first. You do not want to try and put the motor in a hanging frame. The motor must have the head and valve cover on. You cant put them on with the engine in. You can leave the stator off and the starter out and make sure no oil and then you can leave the clutch out. Anything to save weight as the engine is quite heavy.

[Nightviper19]

Ah, that was the kind of tips I was looking for, Thanks! I gotta change the clutch anyhow.
Should I take pictures of the progress as a sort of rudimentary write up or for you guys to give advice?

[Re-run]

Maybe keep a log of what you do for your records. Pics are not required for us unless you have a hard to describe problem.

[Nightviper19]

Ok, what about getting the steel balls back in the steering stem? I got the top in, but it appears the guy before me lost a few balls. 4 to be exact. The bottom is frustrating me greatly. I tried globbing on the grease and sticking the balls in the grease, then tightening it down, but somehow a few balls manage to fall out everytime.

Any ideas?

[Re-run]

If some are missing already, junk it. Get a new kit or better yet a new tapered bearing kit. Make a nice improvement in steering. z1enterprises.com has them for a decent price. About $45 or so.

[Nightviper19]

The manufacture date is 03/76, but it says CB750K Four on the side panels. Sorry to sound nubby, but what would I be looking for? How does the new tapered kit improve steering?

[Re-run]

You would have a k6 then. The tapered kit allows better centering on the steering for better straight line stability. It also operates smoother for better turning.

[Nightviper19]

Hmm, wonder why the original side panels say Four and the manufacture date suggest 6. Whats the difference? Would the tapered bearings be the same for both? If so, what set should I get?

I got the wheels on, and did the compression test, suggesting that the engine is good. Any other body parts/panels/brackets need to go on before the engine gets mounted?

Thanks again for the help. Sorry, I dont know much about these bikes.

[Nightviper19]

Hmm, wonder why the original side panels say Four and the manufacture date suggest 6. Whats the difference? Would the tapered bearings be the same for both? If so, what set should I get?

I got the wheels on, and did the compression test, suggesting that the engine is good. Any other body parts/panels/brackets need to go on before the engine gets mounted?

Thanks again for the help. Sorry, I dont know much about these bikes.

[CB750Winger]

   Like rerun says, you have a CB750K6 such as I have a CB 750K5 (1975) model for example. The 750 Four on the side covers is just a plug for (4 cylinder). I have a flat spot at the straight ahead (center) position on mine so I'll be doing the steering head bearings soon for smooth operation. Go by the manual on this so you don't get too tight and have a problem with handling or too loose will also be a safety issue like a wobble at high speed. If you run into a snag, you can ask for example pictures from these guys. There is a lot of great help here.

[Nightviper19]

Im gonna get the tapered ones since I cant get the balls in place. Anybody got a link or know a good brand to get?

[Nightviper19]

Uh oh. I did the compression test myself after being told that it was good, and cyl 1 was 150, 2 was 60, 3 was 90, and 4 was 120. Im gonna put some compresses air in the cylinder while its at top dead center and try to find the leaks, but do you guys have any other ideas?

Sorry for all the questions. Im just trying to get this project knocked out soon...

[Re-run]

1 sure looks good. redo the test just to make sure, #2/3 are kinda hard to get to and so may not have read right. If the readings are repeated, put tablespoon of oil in each cylinder and try again. If it goes up quite a bit, then you need rings or a cylinder hone. If no change, you are looking at valves most likely.

[Nightviper19]

Wow, you guys are good. I just got off the phone with my mechanic that owns his own bike shop (The one I worked at during the summer) and he told me to do the exact same thing.

But, my compression tester was losing compression consitently, probably because it was a harbor Freight special.  I replaced the shrader valve and shrader O-ring, and redid the test. All cyl except 2 got 155, and cyl 2 for 145. So I should be good.

Anything else I should do/check on the engine before putting it on the frame?

Again, thanks for the help, and sorry if Im a nuisance.

[Re-run]

Comp is good all around then. I would get the head and valve covers all on and get them torqued to spec.
One thing to leave off is the oil filter and it sticks out and would make it a pain to put the engine back in.