Topic: 1970 CB750 fouling plugs

[kaysystems]

The manual says 26mm float height for the K1 & later. I assume the K0 & Sandcast are the same. They used the same brass floats

David

[Bob Wessner]

Dave,

Yes, uses the same 26mm. I've been using a small steel rule with a sliding "T" sort of a pain to keep making sure the slide hasn't moved, thought about riveting it in place. To make sure I uderstand, re: your diagram, the square part rests on the carb edge and the arm/rectangular part is rested against the float bottom? And yes, the floats are brass on the K0 also.

[kaysystems]

Just put all the Honda jets & neesles back. Since it is pouring with rain here today, I had nothing better to do so I took the carbs off & cleaned them with spray carb cleaner to make sure all those small passages are clear. I'll rebalance & go for a ride tomorrow.

David

[kghost]

Bob,
The notched part acts like your sliding T rule. The square part is just a check to make sure thier not too low. GO-NO-GO. Floats are composite on the K2.

[kaysystems]

Nice & sunny again today, but only 50 degrees.

Started it last night and ran it for only a few seconds to se if everything was connectoed OK. Wouldn't start this morning - wet plugs.

Changed the plugs and then balanced the carbs (4 cables are so much fun)

Went for a ride. Yes it runs much better, but there is still a little hessitation when trying to accelerate from slow running - let's say 30mph in 3rd or 4th.
I may drop the needles one more time. Currently they are in the second from top, which is still way leaner than those Keysters in the top notch.

Certainly rideable, even if the plugs are still nice & black, but not quite as hairy.

Also trying to figure out how to recut the plug seating faces without removing the head. They are not flat & can give minor leaks, but not enough to cause major grief.

David

 

[kaysystems]

Tanks guys for all your info & encouragement. Finally took my wife for a ride today. The stock Honda needles are in the lowest position and it works. Still very minor hesitation after slow running but not bad.

I found some 110 jets (Standard is 120)......maybe I should change them?

Thanks again

Davod

p.s. Maybe now I'll get time to restore the first bike I ever bought. A 1966 Ducati 250 single - overhead cam - 8500 redline - 5 speed transmition. Handles like a dream. Bought it in 1974 & still have it.