Topic: Introducing myself: CB750 in Michigan

[xlemming]

Hi everyone, I've just recently purchased and registered a '78 cb750 here in Grand Rapids, MI.  I had a small issue registering it because the previous title had the engine number as the VIN number, but I got that cleared up with an inspection.  The motorcycle looks a little bit rough, but it seems to be running ok.  I has a seat from what looks like a cb350 strapped onto it, and the tank is painted a stupid color.  It also has a weird aftermarket airbox that doesn't have an air filter in it, but I should have that sorted soon too (might just run some cheap pods).  The ignition is retarded a little too far, so once I get a timing light I should be fixing that also (getting a transistorized ignition from Hondaman to help with this also).  I expect to have a number of other issues that I'll need help on, the information on this board has helped me already.  Thanks for your help and interest.

[burmashave]

Thanks for your help and interest.

You'll find the member a visual bunch--interested in pictures. ;-) Post some if you can.

Good to have you here. I've got a '77 CB750k myself. I'm glad to here that you got the title sorted. From what I've read from other members, that can sometimes be a real pain.

Pods might be a good idea. Unless you really want to keep everything as original as possible, the stock airbox is big and clunky. You might want to check the FAQ's for parts sources. Or you could do a search for Pods. Many members have their favorite brands and filters. Personally, I'm running velocity stacks (non-filtered inlets), which are prolly not the best idea in the world.

I'm also using a transistorized ignition. Less fuss, and I doubt you could go wrong with anything that passes through Hondaman's fingers.

Good luck.

[xlemming]

Well, a picture is worth a thousand words, so here we go.  Its a little rough, missing both sidecovers, some scratches and dings.  Nothing I didn't expect though.  I just stuck on the pods today, they seem to be working better than the previous airbox.  Did i mention that the previous airbox was just a rusty box with no air filter?  I attached a picture of it if anyone is interested, I have no idea where its from and can't find an air filter to fit it.  I am having a small issue with my idle screw backing out (pain in the butt at stoplights), right now its being held in place with a little duct tape.  I will do a search and see if anyone else is having the same issue and if there is any easy way to fix it.

[xlemming]

And one more for the airbox.  Has anyone seen or run an airbox like this before?  I thought it looked ok, so I tried to find a filter for it, but with no luck.  I also attached an older picture of when it was installed.  I got the pods at a decent price though.

[Johnie]

Welcome from WI...

[burmashave]

Great pictures. Those are some funky flames. ;-) She looks like she's in very good shape cosmetically; I don't see much rust at all.

I've seen an airbox like that as a new-in-box custom-type part from the 70's. Some of the oldtimers would know better. I think you might be able to line the inside with proper foam if you want to use it. That should be relatively easy and cheap, and I don't know that you'd be able to track down an original replacement.

I am having a small issue with my idle screw backing out (pain in the butt at stoplights), right now its being held in place with a little duct tape.

I'm guessing you mean the idle speed set screw. Does it have a spring behind the screw to keep it from turning? Also, it appears as if the carbs on your bike may be from a 750 older than the '78. Some of the more knowledgeable folks around here could help you get them identified.

[edit: typo]

[xlemming]

Yes, I do mean the idle speed set screw.  It has the screw and the spring, but I feel like the "spring" in the spring isn't as strong as it should be.  When I was talking to the parts guy from the dealership he said there should also be some sort of nut to go along with the screw and the spring and that Honda sells all three as one piece.  Can anyone shed some light on this?

[burmashave]

xlemming, have you had any luck with the idle set screw? I've looked at a couple of parts diagrams; however, I don't think I can help much. It appears to me as if the '78 carbs have just a screw and spring. Earlier ('76) carbs seem to be the same, but it's difficult to tell from the diagrams. I have a '77 CB750 and would be able to give you a better idea except that I am running aftermarket carbs.

For a quick and dirty fix, would it be possible to "tighten" up the spring by inserting some washers under the spring?

You might try posting this as a new question to the general forum. A picture of the carbs might help because I have a feeling, although I am by no means an expert, that the carbs may be from an earlier bike.

[xlemming]

I have gotten the idle speed set screw problem worked out now.  The spring on the idle speed set screw was not the right spring and a little too short.  I went to the local Honda shop because they said they might have a spring around that would fit it, but they didn't have anything quite right.  A short stop at the hardware store found me a nice spring that seems to be working out well.  Thanks for your help.
I will probably take a bunch of pictures of the carbs and start a thread in the main forum to see if people can help me identify them.  It would be good to know which carbs I have.

[Fuzzball]

Hello from the UP and welcome!
Congrats on the 78. Hope you like yours as much as I like mine. Looks like the makings of a nice bike with a just a new seat and tank paint being your major needs.

Have you been here yet?
http://forums.sohc4.net/index.php?topic=12888.0
It's the famous Who's in Michigan thread started by Chris.

That thread spawned a large e-mailing list of Michigan SOHC4's if you're interested.