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Discussion Starter · #1 ·
HELP!!!!! I'm so close, but seemingly so far.
Backstory, bought a seized basket case 74 360 two years ago. Completely stripped and and rebuilt into my dream cafe racer. Motor is fully rebuilt with new rings valve job etc. Bought brand spanking new Mikuni vm30's and put it all back together. Fired it for the first time last weekend wth no adjustments to the carbs. Literally straight out of the box, onto the bike, bike fired.
The problem was that the right cylinder was not producing the compression it should and the motor was only firing on the left side. Took the motor back out, tore it back down and found an issue with a piston ring as well as an exhaust valve leak. I fixed the ring, had the cylinders rehoned for good measure, fixed the exhaust valve and got the motor back in the bike.
Since I had some time I figured I would read up on setting the Mikunis, I watched all the videos, read all the posts and really went to town "dialing" them in. Synched slides with 1.0mm wire as described in the tuning manual, synched both cables perfectly.
Went to start and nothing...wont fire. Found plugs to to bet wet and copious amounts of fuel in the cylinders. Of course I did not discover this until I had run the battery completely down and turned every screw I could find like and obsessed crazy man...Of wait, I am an obsessed crazy man.
As it has been often said, nothing good happens after midnight, so I gave up and went to bed. This morning, before doing anything, I gave a shot of starting fluid and it touched right off, no carbs attached just a quick shot in the intake.

SO, where the heck do I start and what would have caused these to flood. I know none of you were there, and I can assure you I know I am at least 99.9% responsible the issue (i lay .1 percent on the dog, he distracts me) but I am wondering about what conditions can cause these to flood at start up. I am 100% new to mikunis, I have had several 360's but always run stock carbs.

Thanks a TON!
Steve
Fargo,ND
74' cb360
85' 454ltd
64' supercub
 

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Edit: sorry, I didn't fully read.

Maybe give the starter motor a break and try the kicker.

Fuel on
4 slow kicks
Ignition on
Choke on
Hard kick x6
Break and repeat.
If it doesn't work out the first two rounds then try and vary throttle opening. Cracked slightly. 1/4 open. Half open. Etc.
Good luck
 

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Discussion Starter · #3 ·
Any recommendations on air screw setting starting point? Does this even affect fuel on start up?
 

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Discussion Starter · #5 ·
I would assume they are clear, they are new, but we both know what assumptions lead to...
I will check them tonight before I embark on the next journey of frustration.
 

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Discussion Starter · #7 ·
Coils,condenser, plugs and points are new. Spark present when plugs are grounded to the case. Timing is dead on set with test light. Compression is solid, cylinders measured in spec, honed and new rings, valves lapped and holding 110psi from leakdown gauge.
 

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Discussion Starter · #8 ·
So yet an other chapter in "nothing good happens after 10:00pm in the shop" book. After trying everything I could think of I happened to have my hand by the intake during a cranking cycle and noticed air being pushed out of the carb... out came the compression tester again and lo and behold my 160psi compression was at 45lbs on both cylinders. It seems in my late night haste to get the motor back together, I did not verify that the cam chain sprocket was properly aligned after tightening the cam chain slipper hold down, I was off 1 tooth. As a result my intake valves were open during the compression stroke. Reset cam chain sprocket,tappets,timing and carbs. Bike fired on the first kick. 10:00pm is officially time to set wrenches down and pick beers up from here on out :).

Thanks to all for suggestions -in the immortal words of Ronald Reagan "Trust but verify". Just be cause things were good before you took them apart, does not mean they are good after you put them back together...

Steve
74 CB360 cafe
85 454 ltd
64 supercub
 
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