Helping buddy w/ CB350 twin. It runs! Sorta...

I know it's not a Z, but I'm sure some of you have had one of these along the line. Maybe you can help... Been helping my buddy getting a 1970 CB350 twin back on the road for his girlfriend. It sat for 15 yrs. We're going through it step by step (seal tank, clean carbs etc) and actually got it running :woohoo: - on left cylinder only :pinch: .

Cyl #2 is getting fuel (plug is wet) and spark, piston moves freely so next thing is replacing points and checking timing, then checking valve clearances.

Now for my question: Upon opening the alternator cover to turn the crankshaft there's oil seeping out of the alt housing. My first thought was a blown engine seal, but somebody told my buddy that on some CB350s the alternator housing is "wet", in which case some oil in there would be normal. Anyone know?

Post edited by: dutchz, at: 2006/01/30 02:31

The alt. on my 71 CL350 is "wet" but I consulted my shop manual anyway. From what I could find in it,all of the 250-350 twins from 64 to 74 have "wet" alternators.

Thanks man... That's all I needed to know. They paid very little for the bike but I wasn't looking forward to splitting the cases. We can go ahead and mess with it some more then :whistle:

If you have spark and you have fuel in the cylinder that isn't firing, do you have compression? I would certainly do a compression check before investing a lot of work on this bike.

Thanks WG... I'll take my gauge with me for sure.

Alright, spent most of the day getting the piece of crap going. Oh, that's right, CUTE piece of crap, I'm sorry. If I never have to work on a KEIHIN carb again it will be too soon. Stupid plugged in jets (vs screw in) with decrepit o-rings.

Anyway... she runs, intermittently on TWO cyls but mostly on one. Camshaft is so worn that you can't get the timing right if you set the point gap within spec. The point gap (new points btw) can be set with a match stick from now on, it's about the right size. Only took me two hours to figure that out. Alas, she's firing. Now if we can get fuel into the right carb consistently we're rockin and rollin'. For some reason the fuel supply jams if I put the bowl back on. Gotta fiddle with the floats I gues...
What's a good Mikuni equivalent for a 1970 or so piece of grml&%... CB350 twin?

Post edited by: dutchz, at: 2006/01/30 02:30

Dutchz, Measure the inside diameter of the Keihin carb where it fits into the intake manifolds on the cylinder head. You can generally find all kinds of Mikuni singles that should pretty much swap in. You would want to keep track of the pilot jet (or slow jet) size on the Keihin as well as the main jet for a reference and then jet your Mikuni single accordingly. Keihin pilot jets tend to be a bit bigger as near as I can recall... you will want a #15 or #17.5 in the same sized Mikuni but main jets should be similar...

My lack of knowledge regarding the 350 twin keeps me from getting more specific. I personally don't like to use the word Hond... errrr Hon... errrr I just can't say it, sorry. hehe

Thanks wg, we might go carb shopping later this week. Notice I can't say Hon...Hon...Hon$% either. I already called her a lot of other things though haha.

Single Mikuni VM carbs seem to go cheap on eBay. Make sure you get the kind that has some way of actuating the throttle and some way of getting the choke open as the Mikunis use plungers which would be kind of hard to grab with your fingers.