New to me cb750

Posted: Mon Apr 17, 2017 9:08 pm

ive never really read much into the CB 750's but always liked them...i think i almost bought one years ago when i first started riding but passes on it.

well i stumbled across one a couple days ago for $300 and thought sure lets see if i can get it running and do some sort of build on it!!

ive done a handful of tear downs and restores on newer bikes, all FI so this will be my first attempt with a carb.

so i picked her up last night, shes a little rough but not bad considering, she hasnt been fiired up since 2003 or 04 and has been sitting in a barn.

i think its a 750K seeing that its a 1980, she has about 60,000km on it..no clue if its rolled over or not...whatever.

no throttle on it... battery is cracked open and im missing the side covers..which i dont think ill need.
im debaiting on if i should just replace the whole wiring harness.

the plan is to get the motor running and make sure shes worth investing some money into, then full tear down, powdercoat the frame and build her back up.

i even have the big front fairing with a tape deck and hard luggage for her...but i dont think it will ever make it back on.

http://i804.photobucket.com/albums/yy325/ghettomike20zz/17862317_1520643324614393_1432269747947885364_n_zpsg0xtrodp.jpg

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Posted: Tue Apr 18, 2017 7:15 am

Welcome to the site EaZ8 ... Smile

Please be a bit more specific as to your location .

Your bike is about what I started out with , only mine was torn apart and headed for the junkyard .

Posted: Tue Apr 18, 2017 8:31 pm

updated some info.

can you give me some direction... i want to do a build kinds like this one, and i cant figure out where the battery is. i mean the bike still needs some sort of electrical for the lights and starter..

http://bikevx.com/wp-content/uploads/2014/12/featured.jpg

Posted: Tue Apr 18, 2017 8:52 pm

more importantly... i keep seeing cb750k 750f 750c.... how do i know what model i have??
ive searched and cant find a vin decoder.

i need to chase some wires and try to see if i can get it to turn over eventually, would be great to be able to read a wiring diagram for the correct model lol

Posted: Tue Apr 18, 2017 9:21 pm

There should be a boiler plate on the steering neck with the relevant info.

Posted: Wed Apr 19, 2017 6:19 am

The tank looks like a "K" model. Look on the left side of the neck for the vin plate.

Posted: Wed Apr 19, 2017 10:25 am

Black engine makes me think 1982 model.

Posted: Wed Apr 19, 2017 11:53 am

folsoml wrote:

Black engine makes me think 1982 model.

the ownership and neck both say 1980.

also, i think the engine is silver...just covered in filth and a bad picture.

im going to go play with the bike this weekend(its in my friends garage). local honda dealer has plugs and a oil filter waiting for me.

im going to hook up a battery to it and try to hotwire the starter button..i have working keys for it.

Posted: Wed Apr 19, 2017 12:01 pm

From the NMT :

When you post, you need to make sure the checkbox labeled "Attach signature (signatures can be changed in profile)" is checked. It should be checked by default, but if it gets unchecked, you need to re-check it for your sig to appear. It is supposed to stay in whatever state it was in the last time you posted. So it should always be checked. See the pic below:

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Thanks . Smile

Posted: Wed Apr 19, 2017 12:10 pm

The single rotor, single puck caliper and fork is 1980.

I think it's a frankenbike.

Posted: Wed Apr 19, 2017 6:12 pm

genesound wrote:

The single rotor, single puck caliper and fork is 1980.

I think it's a frankenbike.

could be..ownership and neck both say 1980.
i was at the honda dealer today and got a oil filter, they thought they had the plugs in stock but didnt...they will be in on friday.

apparently some guy that is in sales there is building a cafe' racer or has built a few so i got his card and he says he has some spare parts he would sell...no clue what i need yet though.

Posted: Wed Apr 19, 2017 6:57 pm

Hi EaZ8! Before you get too deep into the project you should know that stock carbs on these bikes don't run well with pods unless they are greatly modified. Good luck with sorting it out.

Those handlebars are interesting too. Maybe custom made? It could be a stock throttle wouldn't work with those bars and someone took it off for another project?

Posted: Wed Apr 19, 2017 9:24 pm

DRF64 wrote:

Hi EaZ8! Before you get too deep into the project you should know that stock carbs on these bikes don't run well with pods unless they are greatly modified. Good luck with sorting it out.

Those handlebars are interesting too. Maybe custom made? It could be a stock throttle wouldn't work with those bars and someone took it off for another project?

you are talking about the mini cone filter pods that go on the carbs?
right now i want to make sure the motor is still good before i start modding and restoring.
starting with oil, new fuel and seafoam, then ill have to hotwire the starer because there is no start button.

after i make sure the motor is fine then ill dig into more modding...pods are definitely what i want to do so if you can give me some direction that would be appreciated.

so do i just need so rebuild them with different parts or complete different carb...or is it just a matter of tuning?

Posted: Thu Apr 20, 2017 12:27 am

I went with Mikuni smoothbores years ago (pretty much extinct now) to get rid of the stock carbs. Get ready for sticker shock though if you want some Keihin CR29s.

Posted: Thu Apr 20, 2017 9:29 am

Fuel tank is a 82-83 750sc tank. Chrome chain guard is 750 custom

Posted: Thu Apr 20, 2017 7:03 pm

holysmokes wrote:

Fuel tank is a 82-83 750sc tank. Chrome chain guard is 750 custom

ok...getting a little more info on it i guess.

is there any sort of reference chard that i can look up vin and motor s/n?

Posted: Thu Apr 20, 2017 7:39 pm

it came with this fairing and matching hard bags.

http://i804.photobucket.com/albums/yy325/ghettomike20zz/P_20170416_214657_vHDR_Auto_zps7hsx4xvm.jpg

Site image limit is 640x480 . pd750

Posted: Fri Apr 21, 2017 8:02 am

I can't see your pic, but none of the 79-83 750-1100 DOHC models came stock with a fairing or luggage; unless you count the little bikini fairing on the 1100F.

We're trying to tell you the model (C, K, F, SC) is on the neck plate. Go look at it again.

The engine number will tell you what model it came out of, but that's not really useful except to tell you the displacement (which I believe is stamped on the front of the head or cylinders anyway). There is an engine number decoder floating around the site somewhere. Maybe in the tips n tricks section, I think PD750 was the author.

Posted: Fri Apr 21, 2017 9:43 pm

im heading to the shop to tinker around with it after work tomorrow...so ill take a look at the neck at that point.

Posted: Fri Apr 21, 2017 11:02 pm

It should have a plate something like this on the steering neck, but a different model of course, this one is from my 83 1100F

Posted: Sat Apr 22, 2017 9:09 pm

Well i didnt get to tinker with it much today but i did check the neck...it matches the ownerships vin, its a 1980 CB750 C
i should have taken a pic but i didnt...

one thing i noticed is there is oil coming out of the left exhaust.

the oil thats in it doesnt look all that bad, it was probably changed then put into storage.
i put it in 4th gear and we were able to kinda push it a little so i dont think the motor is locked up.

the choke lever is jammed, she isnt moving at all, so i have to get that sorted out obviously to get her running.

i just placed a order for Honda GN4 so im waiting for that to come in so i can dump the oil and then see what it takes to turn over.
so here she is out of the carage and in good company.
My buddies Chopped Sportster, my 1980 CB750 and my 2009 CBR600RR... few cool mods on her.
wish i still had my sportster but i sold it...years later i came across the new owner and she is being treated well and knows if it goes up for sale i want it.

http://i804.photobucket.com/albums/yy325/ghettomike20zz/IMG_20170422_213448_324_zpsmbg2uubg.jpg

anyway.. shes not looksing all that bad... the motor is definitely dirty, cop webs in all the cables. im going to degrease it, scrub it down then get it painted and casings powdercoated.

Site image limit is 640x480 pd750

Posted: Sun Apr 23, 2017 8:49 am

If you have a choke lever you have a 750sc

Posted: Sun Apr 23, 2017 4:26 pm

holysmokes wrote:

If you have a choke lever you have a 750sc

its more of a plunger and its close to the ignition

Posted: Sun Apr 23, 2017 5:44 pm

Then it's not as you say a lever