CB750.... hmmmm

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Arne
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CB750.... hmmmm

Post by Arne »

I picked up a fixer upper 1981 CB 750c from my brother in law.

Its got 24,000 miles on it, in okay shape (never been down)

It ran well a year ago or so when I went through it for him (its since been sitting).

It needs sidecovers and exhaust, and the tires mounted on it (previous owner picked up new tires but never mounted them). Other than that it runs right down the road.

Soooo, the question is what to do with it. I can get my cash out of it fairly easily as it sits, or I can use it as a rider for awhile and sell it in the spring. The CX650 is a bit too small for me (my knees come up too far)

I've been thinking about turning it into a street racer, as some of the CB750's look pretty good, but already have enough projects floating around....

Anybody have one of these in the past?

How good are they for miles without overhauling?

Hmmmm... choices choices.
1954 Harley ST165 basket in the attic
1972 Suzuki GT750 project in the works
1981 Honda CB750-1000 driver
1982 Honda GL500 easy project
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tz375
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Post by tz375 »

Arne,

You know the answer. Look into to your heart and what do you see? A space where that bike should be sitting with a Cafe Race look.

No need for big bucks. get it running with good rubber and then find/make clipons/clubman bars and rear sets. Find a cheap cafe seat and a 4 into 1 pipe and you're good to go. It can be done progressively once it runs.

Those motor can run for big miles but keep and eye on all those chains - cam- primaries- rear.

The carbs are OK for about 80 plus HP. Dyna ignitions are still available as are exhausts etc. Did you check out the cafe racer website for SOHC 750's?

A man can never have too many projects - except I have too many already... :roll:
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frappy
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Suzuki 2-Strokes: T500M, T250-II, GT750J
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Post by frappy »

I remember reading someone here used to work on them and recently (past 6 months) picked up a red one - was it possibly Wayne?
'75 - T500M
'72 - GT750J
'70 - T250-II
Wayne Meuir
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Suzuki 2-Strokes: 1976 GT750
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Post by Wayne Meuir »

Yea, I picked up a 78 CB750F about six months ago. Rebuilt the carbs, checked the timing and put a battery on it and it fired right up, but the cam chain was REALLY making a racket and the adjuster would not stop the noise. I pulled the engine out last week and was planning to top end it, but once I got it out, I worked on the cam chain tensioner a little and I am just going to adjust the valves and put it back together and see how it sounds.

This is a big heavy bike. I had a 78 750E Suzuki and I really don't remember it being this big and heavy.

Working on one of these really makes you appreciate two strokes. :lol:

Wayne
Luck will beat skill any time you have enough of it!
Gordon
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Post by Gordon »

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Last edited by Gordon on Tue Apr 14, 2009 7:26 am, edited 1 time in total.
Arne
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Post by Arne »

Well, I saw these on my local craigslist today, so I took it as a sign.

Image

Looks like the CB750 will be a streetrod after a few more parts like that!

Thanks guys - Arne
1954 Harley ST165 basket in the attic
1972 Suzuki GT750 project in the works
1981 Honda CB750-1000 driver
1982 Honda GL500 easy project
Arne
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Post by Arne »

I picked this CB1000 engine up off the local craigslist, with a little crankcase modification and jug swap action I'll have a chain drive CB1000.

Now it's starting to look like a project!

Image

I'm not quite sure how racy it'll end up.... as it's going to be a sizeable bike when its all said and done. Maybe just a ducktail seat and a new paintjob will wrap this one up....

QUESTION:

They've been telling me that the stock CV carbs will need limited adjustment (apparently they're tolerant of changes on these honda 4 strokes)

With new exhausts and 350 more cc's I'd be surprised if I didn't have to re-jet, but I'm not a four stroke guy. Anybody know the answer?
1954 Harley ST165 basket in the attic
1972 Suzuki GT750 project in the works
1981 Honda CB750-1000 driver
1982 Honda GL500 easy project
rngdng
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Post by rngdng »

I'm not sure the answer is known! Good luck with it. Should be interesting.


Lane
If you stroke it more than twice; you're playing with it.

Too many bikes, too much time, ENOUGH SPACE, FINALLY! Never enough money.........
Gordon
"Which one is not like the others?"
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Post by Gordon »

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Arne
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Post by Arne »

Gordon wrote:Here's mine -- pretty much bone stock except for the Supertrapp exhaust and the paint job.

Image
Very cool. Did that DOHC come with the CB750 four logo on it?
1954 Harley ST165 basket in the attic
1972 Suzuki GT750 project in the works
1981 Honda CB750-1000 driver
1982 Honda GL500 easy project
Gordon
"Which one is not like the others?"
Posts: 169
Joined: Sat Nov 22, 2008 3:50 pm

Post by Gordon »

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Last edited by Gordon on Tue Apr 14, 2009 7:26 am, edited 1 time in total.
Arne
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Post by Arne »

So I picked up some honda line rear hardside luggage pieces. In decent shape, but they have a couple hairline cracks in them around the handles and latches.

I'm going to paint them, but don't want the cracks to transgress through - I'm not a body work guy by any means.

Options that come to mind are:

Epoxy

Fiberglass patching kit.

Plastic welding.



Anybody ever done this sort of thing before?

Image


Image

(I didn't pick up the parts bike, just the hardsides off it.)
1954 Harley ST165 basket in the attic
1972 Suzuki GT750 project in the works
1981 Honda CB750-1000 driver
1982 Honda GL500 easy project
rngdng
AMA Superbike
Posts: 1769
Joined: Tue Oct 14, 2008 6:47 pm
Location: Blythewood, SC, USA

Post by rngdng »

I had a similar set of bags. I did lots of repairs on them with fiberglass.



Lane
If you stroke it more than twice; you're playing with it.

Too many bikes, too much time, ENOUGH SPACE, FINALLY! Never enough money.........
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m in sc
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Post by m in sc »

i had an 81, i hated it. was a tank and those carbs were a PIA. but, it ran for 3 years till it slung the timing chain.

the sohc bikes, much better imho. had a75f for 6 years. never missed a beat.
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tz375
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Post by tz375 »

I had a CB900 along with a few spare CB750 and 900 motors a few years back. The worst job was grinding valves and setting the shims.

Once I had it together it looked great and sounded great but I struggled with the carbs and in the end I put the stock airbox back on. Those carbs are not easy to set up.

As soon as it ran great i sold it. Time to move on to the next project...
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