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[chris72]

Hello all,

Please forgive me if I'm not posting in the correct section. I do not see the primary section. I picked up an 81' cb750 today that I will be converting to a cafe style bike. I just finished building my first bike ever. An 03' vt750dc.

So I've seen pictures of cb750 's with a single sided swingarm and a mono shock. I'm really interested in doing this. Could someone point me in the direction to source the parts? Pros vs cons?

Thanks.

Here's the bobber I just finished.
 

[chris72]

Not sure why the image is sideways. Sorry.

Here's the cb750 too.

[LukeM]

I think this location will work just fine, as you're a projects kinda person.  Welcome to the forum.  Feel free to take LOTS of pictures to document your process, and to inspire others. :-)

Luke M

[chris72]

I saw in your description that you're in cetral ohio. What part? I'm in Dublin.

[Re-run]

Good luck on that. The dohc bikes don't lend to cafe as easily as the sohc years. It can still be done, but may need more work. Biggest bit of advice I can give you, do not use pods on those carbs. It CAN be done, but it doesn't work very well most times. Get a breadbox style filter housing. They look cool and will be much better at making the vacuum required for these carbs.

[chris72]

What kind of obstacles are you talking about? Would you happen to know where to get the bread box style airbox?

[Re-run]

You can find some sites that make new ones, but they can be expensive, depending on your idea of expensive of course.
Otherwise, it is a hunting game to find them. However, if you even a small amount of tools for metal, you could probably make 1 yourself with some aluminum. Probably spend more time trying to find a filter to build it around.

Another option would be to paint or otherwise dress-up the airbox. A painted airbox can look fairly decent.

[shinyribs]

Hope you dont mind me rotating your pics. That was just to pretty to leave sideways.




As far as monoshock on a DOHC CB, you don't have an oil tank to relocate like a SOHC does, but be prepared to find somewhere else to hide the battery and all of your electrical bits. I monoshock'd a SOHC in the Hackjob thread on here. All depends on what s-arm you go with. Some mono arms will require you to mount a point for the dogbones to pull against ( like mine did), but some other s-arms house the linkage in the arm itself, requiring only an upper shock mount. CBR RR arms are like this. Single sidded swingarms (SSSA) are typically veeeery heavy and expensive compared to traditional s-arms. And you are stuck with the stock wheel, unless you are able to re-machine the wheel hub yourself. Or are willing to pay to have that work done.

Welcome to the forum.  Looking forward to what you will build.

[chris72]

I appreciate it and thank you. So what are we talking about to go.with a cbr rr swingarm? Is this a direct fit? What year are you talking about. I've been having a hard tkme finding information on swapping on a dohc. Seems like all the precious years are easier, cbr f2 or the swingarm from a dohc.  Thanks again. I appreciate the help and the warm welcome to the forum by everyone so far.

[chris72]

As far as the battery and electronics my intention is to go with a smaller sealed battery like in did with the bobber. I'll build a seat frame and seat to try and make that happen. Probably extend the depth of the seat frame an inch or so and fab up a pan to go under the seat. At least that's what I have in mind right now lol.

[chris72]

I've also started to look into the parts I'll need to build the breadbox style airbox. Thanks re-run.

[Truck]

Is this what your talking about? I've been thinking about trying to build one, do they really work on the DOHC's

[chris72]

Yes but I have no idea how well they work. I was taking advise from re-run. The precious owner had cone filters directly off of the carbs. Said that he jetted for them. I've yet to start the bike. I did make sure it cranked, brought a battery withe but barely had a charge.  I've been a little under the weather the past couple of weeks due to a stupid heart problem so I haven't even tried to start it. However it's giving me time to research ideas that I have and suggestions that i recieve.

[chris72]

Stupid auto correct lol previous not precious

[shinyribs]

chris72 wrote

Stupid auto correct lol previous not precious

Re: the s-arms. Nothing will bolt in. But according to my measurements the RR arm is close as far as overall width and it looks like the pivot bolt size is a match.

Here's the thread where I put a typical mono arm on a SOHC. vvv

http://honda-cb750-s.456789.n3.nabble.com/78K-Resto-Mod-quot-HaCkJoB-quot-td3941340.html

Here's a build I haven't has time to start yet. But it has some pics of the RR arm. You'll notice the pivot it two ears, rather than a continuous tube. All things that have to be addressed on a case by case base. It a modification I was willing to do to gain the advantage of not having to mount the dog bones. vvv
http://honda-cb750-s.456789.n3.nabble.com/Another-twin-cam-F-td4053992.html#a4056281

If you really just want to go mono,and don't care what the arm looks like, find a mono bike that originally didn't use any type of linkages or dogbones. Get the shock off that bike and mount it to your stock swingarm. That's the easiest way to ditch twin shocks.

[chris72]

Awesome thanks for the input.

[Re-run]

That's it Truck. I have heard those work ok. A lot depends on the filter and how restrictive it is. However, the open area for the filter could be reduced using an aluminum shield, effectively reducing the amount of air that can be sucked in continuously. The breadbox also provides a slightly smother airflow into the carbs that the pods don't do at all.

[Truck]

Thanks Run.

Not sure about how well it would fit, but early 80's Yamaha Viragos had internal mono shocks.

[chris72]

Would anyone happen to know what years have interchangeable parts with the 81' cb750c? From what I found so far it looks like the 79' - 81' are but I n want to confirm. The stator cover needs to be replaced and im trying to find one.

[TOOLS1]

All 79-83 CB 750 DOHC engines are the same. The only differences in the "K", "F", and "C: models were just mostly cosmetic.
TOOLS