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Hello All,

Iam from Columbus, Ohio. I have started a Cafe racer project on my 1978 CB750 Supersport. Here is the image of the bike in its original state and also some pictures of the tear down.

The Original
CB750_1.jpg
The plan
Home image.jpg
The Tear down
bikeimg7.jpg
bikeimg8.jpg
bikeimg9.jpg
bikeimg10.jpg
engine1.jpg
engimg7.jpg

For more images
motorcycle
 

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yikes!!!!

So I have to ask, did you even get it running before you tore it down?

you do know the 77-78F bikes are different from the 1969-1976 bikes right? Like really different. I mention this because you used a pic of a 1969-1976 bike to do your "rendering". How different? engine internals, frame, seat, tank, foot pegs, exhaust, forks, wheels brakes, etc....If you are looking to use spoke wheels you need to change the forks, the calipers, the caliper mounting brackets, the wheel, the rotors, basically everything but the trees and the swingarm - and the brake tech is a backwards step in tech and not worth it.

so what's your plan?
 

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just so you don't think we are an unfriendly bunch here are some local resources:

If you haven't yet, sign up to the Google group for Columbus Ohio Vinmoto. It's just an email list for local guys with old bikes but a lot of them have knowledge of cb750s. I think it is called Co-OH vinmoto.

Rice paddy is a great resource for parts. There are a lot of upgrades Honda did to the DOHC chassis that work for the SOHC like shocks (cb900F/1100F) and dual piston calipers. Also rotors that are less warp prone.

Iron Pony in westerville is also a great resource for things you can get out of the parts unlimited catalog. things like handlebars, filters, gasket kits, etc...

not local but dynoman.net has a lot of cb750F specific parts. Remember this bike has different head, pistons, and valves that keep it from interchanging things with other 1969-1976 bikes. if you want a big bore kit, better valves, etc...this is where you get them.

Also not local but Hondaparts-direct.com is a good resource for OEM honda parts. I don't know if they are NLA but they used to be available as of last year that you could get the carb insulators. You are going to need them either way based on the condition of the bike so might as well start hunting them down.


So the reason why you should have got it running before tearing it down was this way you would know the condition of the engine. I would have performed a hot compression and leak down test because that would tell you if you need to re-ring the engine or not. If everything checked out I would have said leave it together and don't touch it. However, now that you have it apart you are looking at several hundred dollars in internal engine parts like new rings, gaskets, etc... I don't know the mileage of your bike but these bikes usually need valve guides at 30K miles. But now that you are in there you might as well do the valve guides as well - maybe new valves.


If you get a chance - the first monday of the month is bike night in Dublin at the Dublin tavern by bridge st. The last thrusday of the month is a bike night at at nutter hardware in upper arlington. Saturday morning is cars and coffee at Lenox shopping center off olentangy. There is also a bikes and BS meetup sat mornings at honda powersports at marysville.

Since you are a local, pm me if you need help. I'm usually pretty busy but I've probably owned more SOHC cb750s than I have fingers and toes and happen to know a thing or two about them.
 

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Never go full retard.
never.


sad to have another bike cut up and abused with no understanding....
 

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I'm assuming the rear tire is like a 16" firestone? if so that's pretty cool, I haven't seen many firestones on gsxr front ends, if you run one up front too you'd be doing something different there, that too would be cool. I like the mini cafe/brat seat idea, with the monoshock it's going to look rad, I think the shock you plan to run should be gold colored, even if it's not ohlins, the gold anodizing on the monoshocks just looks "right" to me. not sure where you could put the oil tank without making the mid area look cluttered, I think having it see through is the right way to go, I've actually heard of a guy who welded the oil feeds on his 750 shut and just kept the crankcase extra full, he told me it worked really well and let him have that clean look in the bike frame. keep posting pics as you go, interesting project!
 

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who's corey? naw, I think it's awesome that the everyone gets a trophy generation is modifying dangerous machinery based on instagram appeal, and when going out in a brave new direction, it's usually best to avoid interference from people with their heads stuck in old ideas, they'll only crap on fascinating new ideas
 

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Hey, good dreams. Since the Wrenchmonkees have now sold out, and its up to young dudes to refine the true café racer.

Personally, I'd go rigid with struts on the rear frame, slam the gixxer forks to zero and ditch the front disc for clean looks.

Danger, is my business.
 

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to be fair there is a certain year GSXR fork that if used maintains the stock front end geometry. Of course most people know this by reading the search results at SOHC4.net and not actually getting out the tape measure to verify. the internet can only give you enough information to be dangerous, it's up to the individual's common sense to keep them safe.

Monoshock conversions on SOHC cb750s confuse me. The frame/swingarm wasn't really rigid enough to handle the dual shock setup that was on there in the first place - a bigger lever out back with a single point of connection and no strength of triangulation always seems dubious to me. Or more simply put: look at how beefy a modern sportbike monoshock frame is at the pivot and shock mount, and then look at how unbeefy the cb750 is at the same locations. I mean there are people who have done it, but when it is done in racing those people usually remake the entire frame.

And before someone speaks out of their ass and says "but what about ducati", remember ducati swingarms attach to the engine, not the frame and that part of the engine case is hella beefy. It's easy to be fooled because the individual tubes in a duc trellis frame don't look that thick, but when you compare the whole structure to an alloy jap wishbone you get the net same effect.
 

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Uuummmm
seeley......

Working on getting the chain adjusters made for mine.
hope to find a parts bike over the winter and have a seeley beater bike for the spring.

now that I have a proper job I can fund the project.
 

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All those late F bikes really need are a good pair of slightly longer, quality rear shocks, A rear muffler that doesn't weight 100lbs, and a good set of tires. Sure the Comstars don't look as retro as spoked wheels but the fuctions better, and have much easier to upgrade brakes on them. The bike is still gonna corner like a truck though
 

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All those late F bikes really need are a good pair of slightly longer, quality rear shocks, A rear muffler that doesn't weight 100lbs, and a good set of tires. Sure the Comstars don't look as retro as spoked wheels but the fuctions better, and have much easier to upgrade brakes on them. The bike is still gonna corner like a truck though
And you can make the handling even worse by adding a monoshock rear end, since that will extend the wheelbase even more. So then you can have a top heavy overweight pig that handles like a locomotive.
 

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Oh I know. I tell people that all the time. In fact I told that Gasser Customs guy that to his face when I saw his CB750 that was featured on Jay Leno's Garage. I then proceeded to confirm my bone stock motor with 30k miles on it, AAA 4-1 pipe and velocity stacks is faster stop light to stop light than his 836cc kitted bike with a cam, custom exhaust and pods.

1975 Honda CB750 ?Titan? by Gasser Customs | Pipeburn.com

From what I hear he begged and pestered Jay all over Burbank until he got the bike on the show.
 

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Oh I know. I tell people that all the time. In fact I told that Gasser Customs guy that to his face when I saw his CB750 that was featured on Jay Leno's Garage. I then proceeded to confirm my bone stock motor with 30k miles on it, AAA 4-1 pipe and velocity stacks is faster stop light to stop light than his 836cc kitted bike with a cam, custom exhaust and pods.

From what I hear he begged and pestered Jay all over Burbank until he got the bike on the show.
You have managed to include Tripebuns, Leno, Lame-O , and a junk bike in one post. Good work.

Danger, is my business.
 

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Looking at pictures of that gasser bike I now realize why it is so slow, and sounds so underpowered. He used the fork, wheels and swing arm off an Interceptor (adapted to twin shocks). But if you look at the rear sprocket, also off the Interceptor, its about 10 teeth smaller than a stock CB750 rear sprocket!

jlglicenseplate.jpg
 
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