1973 honda cb750

Karts of Kaos

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yesterday I got a motorcycle! I cot a honda with a cb750. the motor is seized and has been out in the weather for a long time. the handle bars are broken, the shifter arm is gone, and so is the clutch trigger,there are no valve cover bolts but the valve cover is there. the front break is hidrolic and the hose is cracked. the rear brake is a drum brake and is functional. in total I payed 50$. i will post pics soon.
 

JTSpeedDemon

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Hopefully that lock is as simple as a stuck clutch, but that bike may very well be more trouble than it’s worth. That said, go for it! If it ends up running well, you may have a good flip project or even the occasional around town ride!
Obviously, if you get to ride it, don’t hurt yourself.
Also- just remember parts are a lot more pricey than a 212 :roflol:
 

itsid

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Anyhow, a seventies CB750 Honda is a great bike, and it's a bulletproof engine,
good for well over 200k miles easily.. even mistreated it certainly outlasts quite a few of it's competitors.
You can still buy almost every part of that engine, some bike specifics are harder to find (seats, fairings and such),
and restoring it (the BIKE! not just the engine mind you) will certainly be worth the effort.

'sid
frankly, for 50 bucks.. I'd buy all Hondas I could find just frame, engine, wheels and tank not running IDC...
that's a steal,
waiting for pics :D
 

Karts of Kaos

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oh yeh, i forgot to say it only has 27,794 miles. here are the pics.

and JT I am fairly sure that the pistons are seized because it was left out without spark plugs. it vary well may have a seized clutch too
 

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Karts of Kaos

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today I got the engine out (not an easy prosses I might add.) and I wanted to take off the heads, but I can git the timing chain off . How do I do that with a seized engine?
 

Karts of Kaos

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Anyhow, a seventies CB750 Honda is a great bike, and it's a bulletproof engine,
good for well over 200k miles easily.. even mistreated it certainly outlasts quite a few of it's competitors.
You can still buy almost every part of that engine, some bike specifics are harder to find (seats, fairings and such),
and restoring it (the BIKE! not just the engine mind you) will certainly be worth the effort.

'sid
frankly, for 50 bucks.. I'd buy all Hondas I could find just frame, engine, wheels and tank not running IDC...
that's a steal,
waiting for pics :D
and yes sid I am planning to restore the whole bike
 

itsid

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unfortunately a CB750C bike I'm personally not a fan of those soft-choppers at all
I like the original CB750 four much better but that's just personal taste..
Still the engine is great, only 67 horses but gives you all the torque you need in a bike,

Again for 50 bucks.. it's a steal.. too bad I don't see any tank ..
those can get expensive quite quickly (if in good condition)
and worse the carb manifold flanges are also missing it seems...
that will not only be rather expensive but also not exactly trivial to find,
too many different generations and too many wrong info on offers for motorcycle parts to be sure :(
So chances are you end up with a non fitting manifold.
take great care to pick the right set,
Ideally find the original Honda workshop manual and partslist first.

'sid
 

Karts of Kaos

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thanks Sid, I do have the tank and it is in great con ditio0n on the inside and only has surface rust on the bottom of the tank. it just did not come mounted. same with the headers and exhaust. I just refer to it as a "a bike" but what is the difference between the 750 four and the soft chopper?
 

Functional Artist

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Yes, that's a good deal for $50.00 :)
.,..but, it looks like you have lots & lots of work ahead of you :unsure:

Have you thought about converting it to electric? :popcorn:

My 1980 Kawasaki 440 LTD had a seized engine when I got it
...& now it has an 8,000W motor :cool:

It has lots of torque
...& is super fun to ride :sifone:


 

Karts of Kaos

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I'll consider it FA thanks for the idea. so on Sunday I pulled the heads and well it was rely bad, especially on the #1 and #4 cylinders. so I cleaned it out and put some evapore rust in it and I am waiting for results.

here are some pics of the cylinders. the punch is for scale to show how much stuff there is.
 

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JTSpeedDemon

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YUCK! I think that might be a bit too far gone, but you might be able to get it bored out......*maniacal laughter
 

Karts of Kaos

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sorry i have not updated recently, but i have made a lot of progress. i used some evapo rust (by the way that stuff is amazing) and a heat gun and got the jug off after hitting the pistons with a piece of weewd. I did that i realised that the crank was fine and moved freely. I also honed the borse and they turned out pretty good. I don't have the pics right now. most of the rings were seized as expected. i got the pistons off and opened the case to find that the trans looked fine just a little rust and dirt no broken teeth. but the case has a hole in it (not sure from what) but it had been patched from the outside so I could not tell it just looked dirty. but I think it can be fixed. there really is not that much wrong with this engine. I think it will run for only a few hundred dollars. I think it will need rings, a case weld, crank and rod bearings, gaskets timing chain, and carb parts.
the bike it going to need new handlebars and other things, but I was wondering how hard it would be to make them. I did find them on the internet and they were only lif fifty dollars but I still think it would be cool to make.
also a friend of mine ,a car enthusiast, told me that it has the wrong seat. I was wondering if he was right. it is a 73 I have the title.
 

itsid

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that's an aftermarket saddle, yes
well... chances are it's indeed the original seat-base that was upholstered afterwards,
that was quite common up until the late eighties actually

was quite popular in the 70ies to have a "more pronounced" step
on those soft choppers
so much so that in the late 70ies and early eighties Honda increased that step on the original saddles
quite drastically.
not a fan I admit (the worst about Prince's purple rain is still that fugly CM400A Honda)
similar stepped saddle with a sissy bar cushion cast in. (looks even worse IMHO)

Again a matter of taste.
it's period correct equipment and was rather popular back in the days...
If you want to keep it 'period correct' I think you should keep that saddle as is,
at least it looks to be comfy :D

'sid
 

Karts of Kaos

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the seat is going to need to be replaced. it has holes in it and it is very brittle

I also removed the clutch and I don't know anything about clutches so i can't tell how bad it is but I will post pics.
 
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