Topic: 76' 100$ barn find project: Pending.

[kac3177]

My 76' cb750a project. Running but jetting is off.

Frame off: Powder coated frame, tapered steering conversion, larger k series headlight, k-cam, polished motor, new chain/sprockets, tires, fresh paint.

Running way to lean. Tried pd42b w/ 110's, too lean. Tried pd41a w/ 115, still to lean. Waiting on jet kit now. The kit comes with 120, 122 and 125's. It will only run fully choked. Any suggestions?

Steve-o, Enlighten me, what am I doing wrong?

[Stev-o]

Sounds like you possibly may have 2 issues here, but need more info first. 

How have you determined you are running lean?   What do your plugs look like?

I see a header, do you have a muffler?  Stock  air box??

Bike is looking good, like the tank paint and motor looks fantastic. Now let's get it running.

[kac3177]

It has the stock 4-1 but modified to accept a Harley pipe (see pic). It has a 77' k7 cam and the carbs from the same motor. It will not run unless its fully choked. I tried a set of pd42b's with 110's, cleaned twice, no improvement. I then tried a set of pd41a's and same result, a little better but won't run without the choke. The plug's are light tan however it seems to get hot quick. Stock air box for a k series. Timing is about 5 degrees advanced. Fresh head gasket, boots are in good shape. Adjusted the valve's again just in case, they are good. Have a jet kit on the way, hoping the 120's will balance it out, the 115's seemed close.

Thanks for your help. If it's a car I am good, bike's are new to me. The cb750a is the only bike I can ride with one arm and I really want to make the show next month. My '78 isn't show worthy.