Author Topic: 1972 CB350f carburetor help needed.  (Read 922 times)

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Offline drew949

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1972 CB350f carburetor help needed.
« on: March 31, 2017, 09:25:00 AM »
Hello. A couple of years ago, my father purchased something he wanted since he was a young man -- a 1972 Honda CB350f. He is not the most mechanical guy. As of late, the bike has had some issues, namely some carburetor problems. This model has the Keihin's without the diaphragm. I agreed to take a look. I took out the bank of four carbs and rebuilt them yesterday. I have rebuilt a few carbs in my life, and found the task to be fairly easy. However, I have not had to sync multiples. The problem I am having is in adjusting the slide height. What position should it be in? (The throttle is in the closed position. I probably should have checked before I started, to at least give me an idea. I greatly appreciate any help. Thanks. BTW, my Dad will be thrilled to have his bike running again!
Here are some pics:
« Last Edit: March 31, 2017, 07:04:43 PM by drew949 »

Offline calj737

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Re: 1972 CB350f carburetor help needed.
« Reply #1 on: April 01, 2017, 05:24:19 AM »
A bench synch is usually performed by using a 1/8" round shank drill laid under the slide, slide adjusted down to "just touch" and repeat on remaining carbs. This should get you very close for a slight adjustment of vacuum when installed and running.
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Offline drew949

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Re: 1972 CB350f carburetor help needed.
« Reply #2 on: April 01, 2017, 10:49:56 AM »
I'll give it a shot...thanks!

Offline flybox1

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Re: 1972 CB350f carburetor help needed.
« Reply #3 on: April 03, 2017, 10:33:30 AM »
When you 'rebuilt' these carbs, did you reuse the OEM Keihin jets, or did you add shiny aftermarket ones?
Did you put in aftermarket float valves?
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
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