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Re: CB350 keihin re-jetting: uni-pods and no mufflers

Flooding is only caused by your float taking on gas, being at the wrong height adjustment, or your needle valve not seating properly.

All three of these things are problems I keep dealing with ;)

My needles have grooves worn into them from age. I need to buy new ones. What I've done though to combat the problem was to put toothpaste on a q-tip and run it in a drill inside the needle seat. This ever so slightly polishes the needle seat so it'll hopefully shut off better with the needle.

I bought some aftermarket brass floats on ebay.. 12 bucks a pop.. even though my stock ones looked fine. Therefore I know it's not because my floats are taking on gas now. My stock ones had hairline cracks in the brass.

It's probably best to run the bike with some sort of mufflers. I JUST put on shorty glass packs last night. Having them on really helps it not cackle.. No mufflers is so obnoxious. You may have actually upjetted more than necessary depending on your elevation, but until you solve the overflowing carb you wont' be able to dial that in anyway.
 

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Re: CB350 keihin re-jetting: uni-pods and no mufflers

When the engine revs high after riding, that is usually due to a lean mixture. The proper stoich mixture also helps to cool the engine. Lean mixtures burn very hot, thus causing the high reving you mentioned. Ran straight pipes on my 450 with stock jets. idled so high i had to shut it off at stop lights.

Due to the lack of back pressure, you may need to re-jet your carbs again.
just my .02

-Dan
 

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Re: CB350 keihin re-jetting: uni-pods and no mufflers

That rubber gasket looks completely trashed to me - toss it and get a new one, I think it's still available from Honda.......or get a petcock rebuild kit somewhere.
Don't mess around trying to bend the spring washer, you'll screw things up even worse.
 

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Re: CB350 keihin re-jetting: uni-pods and no mufflers

I bought a new whizzer valve (that rubber thing with the holes in it) last year and the stupid thing leaked worse than before :)

Here's how I sealed mine up:

I wet sanded the face of item 5 (the lever) and polished it to a mirror shine where it mates up against the rubber whizzer valve.

Then I SLIGHTLY bent item 10 a bit so that when the screws are installed it applies more pressure on item 5 against the rubber valve.

The rubber valve? I smeared it in vasoline to soften it up a bit and reinstalled it.

No more leaks after this.
 

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Re: CB350 keihin re-jetting: uni-pods and no mufflers

That petcock Dime City is selling looks exactly like the stock CB400T petcock. You'd need to get a tee if you went with that one since it only has the one outlet.
 

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Re: CB350 keihin re-jetting: uni-pods and no mufflers

NO, put the hondabond back in the drawer and forget about it till you need to open up your engine cases.
you seem to have a multitude of issues so sort them out one by one and do a complete tune up of your bike.
first: buy or download the Honda factory service manual and read it cover to cover twice
second: fix your battery / charging situation... a poor electric system will never alow your bike to run properly
third: set your valves to spec and take a compression reading to make sure your motor is good
fourth: static time and set your points (its a good idea to replace points and condensers)
fifth: buy a handful of spark plugs they are cheap and make sure you are getting good spark on both sides
sixth: buy new petcock seals (all of them) in line fuel filters and fuel hose
seventh: get the proper floats for your carbs and make sure your inlet valves work properly (and replace them if they don't)
eighth: buy OEM honda carb seal kits if you haven't already done so
ninth: start the motor and check for air leaks around the intake manifolds


Once all of those things are done properly and within spec you can begin to tune your carbs.
It should also be noted that your slide diaphram with the hondabond on it will not function as well as a good one and may still prevent you from properly tuning.
 

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Re: CB350 keihin re-jetting: uni-pods and no mufflers

according to the Honda manual, valves and points should be adjusted every 2000 miles on a perfectly tuned motor...it's a safe bet that anything sitting for that long will at least need the points adjusted to account for deterioration from sitting. file them with a points file and readjust. the valves on these motors are some of the easiest out there to adjust...they tend to tighten over time from metal fatigue.

over all though you should never begin on the carbs untill everything else is perfectly tuned since it will throw off your carb readings.

you can wing it and hope things are in good shape but personally I wouldn't.
 
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