CB750C 1982 DOHC budget brat/cafe racer build

[SLM]

Hi everyone I have a CB750C but the engine came without carbs or electronics except the dash
so basically what im looking for is;
-first of all what should i do in order to do a stage 0?
-what is a cheap carb setup? single carb? dual? manifold fabrication is not a problem.
-anyone have experience with creating their own electronics and/or custom or different dash?
-anything i should look out for to fix before i start this build?
-any way to make this thing lighter????not a priority but preferable
-and how does the seat attach to the frame??

looking to do a relatively basic cafe racer/brat build, i should mention this is my first bike ( yes i kw it is not a good first bike cause of the power and weight, feel free to scold, i can take it) any advice is appreciated, thanks

 

[DennisAlan]

Great first bike unless you crash lol
It's my 2nd real bike and I love it. It's a mad max looking cafe racer cause I'm stripping it down to only what I need to ride so that reduces weight.
Before going crazy make sure the engine turns and has good compression and get it started. As for carbs I have the 4 into 2 from Murray's Carbs and it makes setup so much easier. He cleans and sets them up free for life. Unless you really know what to do 4 carbs suck.
I have a few youtube videos on my bike and what I've done if you want to check them out. Search for Dennis alan vids cb750 and you'll find them.

 

[DennisAlan]

Oh and good luck with it!

 

[SLM]

Great first bike unless you crash lol
It's my 2nd real bike and I love it. It's a mad max looking cafe racer cause I'm stripping it down to only what I need to ride so that reduces weight.
Before going crazy make sure the engine turns and has good compression and get it started. As for carbs I have the 4 into 2 from Murray's Carbs and it makes setup so much easier. He cleans and sets them up free for life. Unless you really know what to do 4 carbs suck.
I have a few youtube videos on my bike and what I've done if you want to check them out. Search for Dennis alan vids cb750 and you'll find them.

YES omg i´ve seen ur vids, lol i had actually watched ur vid on the unboxing of murray´s carbs recently, super helpfull by the way, I actually did end up going with a twin carb setup except i decided to make my own cause I wanted it and i wanted it now , i made a 3d printed manifold and I got two PWK34B carbs, i still have to print two gaskets but i test fitted the carbs with the manifolds, fit great, ill get a picture when i can, i also have the same seat! im trying to find somewhere to get the horizontal bars of the subframe welded back rn nd then ill have the seat secured.
Im also trying to decide what to do with the elctronics, im definetly going with an arduino for the lights and horn and all that, but im trying to decide what to do for the ignition, wether to go ECU controlled or go electric ignition, one last thing is im trying to raise the rear a bit, idk whether to just buy longer shocks or make some spacers

 

[SLM]

Oh and good luck with it!

thanks man, nie build!

 

[DennisAlan]

YES omg i´ve seen ur vids, lol i had actually watched ur vid on the unboxing of murray´s carbs recently, super helpfull by the way, I actually did end up going with a twin carb setup except i decided to make my own cause I wanted it and i wanted it now , i made a 3d printed manifold and I got two PWK34B carbs, i still have to print two gaskets but i test fitted the carbs with the manifolds, fit great, ill get a picture when i can, i also have the same seat! im trying to find somewhere to get the horizontal bars of the subframe welded back rn nd then ill have the seat secured.
Im also trying to decide what to do with the elctronics, im definetly going with an arduino for the lights and horn and all that, but im trying to decide what to do for the ignition, wether to go ECU controlled or go electric ignition, one last thing is im trying to raise the rear a bit, idk whether to just buy longer shocks or make some spacers

So cool you can 3d print the intake! What year is it? Is there a file I can have my friend print for me?
Can't wait to see some photos. I'm sure yours will be super clean. I'm going for a screwdriver ignition lol

 

[brettp]

Is the filament fuel resistant?

 

[DennisAlan]

Is the filament fuel resistant?

I hope so or you'll be in some trouble

 

[SLM]

So cool you can 3d print the intake! What year is it? Is there a file I can have my friend print for me?
Can't wait to see some photos. I'm sure yours will be super clean. I'm going for a screwdriver ignition lol

Thanks! Its a 1980 C, I can post the file here but It might not work with any carbs, since the pwk is a flatslide its shorter so on a round slide it might hit the frame, let alone have space for ITBs or a filter, but idk, u can try it if u want
Its supposed to attach to the carb with a TPU gasket which ill post later

an update on the ignition, i think I will be going with the electronic ignition in the end, maybe ill upgrade to ecu later on, any advice on setting it up would be appreciated, if not ill just turn to chatgpt lol

And YES the filament i gasoline proof and airtight lol

Does anyone kw how to upload 3d models here?? its telling me stl not allowed

 

[PWBII]

I don't know the company name but, there is one that makes fibre glass cafe bodies for the cb750s I have one for the 1975. It incorporates the seat & tank into one piece. Your pic shows the stock tank which seems large for the bike @ this stage to me. One to 1.5 gallon should be plenty IMHO. Mines a project I started a while ago & haven't gotten back to. I'll take some pics & post them.

 

[DennisAlan]

Never thought about changing the tank and kinda like the larger capacity. I'm new at what you can swap on these bike but will look into possibly changing it. Always open to suggestions.
Here's more pics of my mad max build

 

[SLM]

Alan do you happen to know what the setup is for your carbs? i mean like jet sizes, turns for idle and air mix, power jet size if equipped, thatd be appreciated

 

[DennisAlan]

Alan do you happen to know what the setup is for your carbs? i mean like jet sizes, turns for idle and air mix, power jet size if equipped, thatd be appreciated

No I don't. Reach out to murrys carbs he built them sets them up for you also.