Custom 78 KZ650b Cafe Racer Build

Hey Guys I have a Custom 1978 Kz650b, Its my first bike and I have worked the past year to get the bike running and into drivable condition, but now I have plans to finish the build. During the next few weeks I will be making a series of videos of the build, I don't have much experience but I am full of passion and I hope to inspire others to customize or buy their first bike.

Here’s what I have done so far.
Suspension: swapped with a 1998 Honda CBR F4i (Front and Rear)
Points: swapped with a Dynatek Dyna 2000 CDI and connected it to the electronic starter from the Honda CBR.
Front Fork: Clip On Handle bars, cut kz650 front fender, new grips and throttle/break cables
Exhaust: It was missing the exhaust when I purchased, so I bought a 1977 kz650 exhaust and bent it to fit the frame.
Carburetors: Cleaned and Rebuilt.
Rear: Modified to fit the tailpiece from CBR F4i, 200 lbs. rear suspension spring.
Tires: 120/70 fronts, 170/60 rear 17-inch rims.

This site along with videos from YouTube have helped me learn a lot and I hope this post can help others, feel free to ask me any question.
In the next few weeks I have a lot of changes and additions I plan to make. I will be replacing all fluids, points cover, gauges, rear lights, side covers, building a new seat, and either repairing the gas tank or buying a new one and modifying it to fit. I will also be painting the tank, engine, and exhaust.

Currently the Carburetors are having flooding issues so I need to figure out if the fuel level is too high, or if the jets need resizing, or if the jets are getting stuck, If anyone has any suggestions or helpful tips, It would help me a lot. I think they are getting stick because sometimes the bike will only run of 3 cylinders and then bog down when using the throttle.

I will be stripping the Bike down today and uploading the video soon; any suggestions or tips would be amazing. I want this bike to be a tool to bring people together and hopefully build friendships. I hope you guys like it and we can help each other built the community as well as a cool bike.

Interesting build. Way better than the typical "hack the seat rails at the shocks and use a board for a seat" version of cafe that are so common.

Keep going...

Quite the project.

Do you know what jetting is in the carbs?
If one cylinder is cutting out, either that carb has an issue, or something electrical is cutting out. Try swapping the spark plug wires. 1&4 share a coil, as do 2&3, so you can swap 1&4, or 2&3.
You can try swapping spark plugs too, as you may have a bad spark plug.

Fuel level is important, best checked using a tube off the drain and held next to the carb.
If the carbs are flooding, and fuel is coming out of the overflow tubes, the float fuel valve & seat may not be sealing, and in need of cleaning.
Sometimes tapping the bowl of the leaking carb will stop the leak, by freeing a sticking float.

SupStin wrote: Currently the Carburetors are having flooding issues so I need to figure out if the fuel level is too high, or if the jets need resizing, or if the jets are getting stuck, If anyone has any suggestions or helpful tips, It would help me a lot. I think they are getting stick because sometimes the bike will only run of 3 cylinders and then bog down when using the throttle.

Jets do not actually get "stuck".

When you say "flooding issues" do you mean the plugs are wet with gas or that there is actually fuel running out of the carbs? A float that is stuck can result in gas running out of the overflow.

I think your issues may stem from using pods without rejetting the carbs, Pods allow more air flow than the stock airbox does, and when you open the throttle the mixture may be leaning out too much for the engine to run properly. (You didn't mention rejetting the carbs so I'm assuming you didn't.)

Hey guys, Sorry its been a while. Always lots to do when you got an old bike. I finished up painting and making the bike look good. Carbs have been fixed for the most part still leaks gas after riding, but the bike is running and driving. The clutch is worn but not bad, 3rd gear is slipping so I need to take apart the tranny & engine to fix. Bike is for sale now, Im tired of fixing it so time to move on to the next project.