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Discussion Starter · #1 · (Edited)
Hey guys --
This is my first post here, so hopefully i'm not out of place.
I just recently purchased a non-running 1968 CL350 (with a 1968 CB350 engine on it), and I've been slowly working on it trying to get it back up in running shape. I knew it was going to be a project, so I'm not bent out of shape from it (yet), but I just can't seem to get this thing firing correctly. Just for sake of details, it also has Mikuni VM30 carbs on it. Came on it with the bike, I have the original carbs with damaged diaphragms.

Here are the things I've done so far:

  • Verified spark, verified gas
  • Flipped the advanser plate cylinder/shaft/tubething (it was on upside down/reversed so my breaker timing was crazy off)
  • Set the breaker timing with a light on compression strokes
  • Set the tappet clearance per the manual at tdc on both cylinders

Symptoms:
Bike doesn't start, exhaust sucking in air, carbs barely sucking air.


The only thing i can think is that there's something wrong with the valves, just not sure if there's anything I should try BEFORE ripping apart the engine/taking it to someone.
It does have some form of compression that I can feel when I put my thumb over the spark plug hole and rotate the flywheel - it doesn't feel very strong though.

Thanks in advance
 

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take a compression test and let us know what you get.

I have a feeling your valves (the exhaust ones) are not sealing. Could be a bent or damaged valve, could be valve seals.
 

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I would go for the stock carbs, and buy some new diapragms.
But check the compression first with a gauge
 

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remove the bolt from the end of the cam shaft where the ignition advancer attaches and post a pic.

I think your still timed off somehow and want to see what you have

have you confirmed your cam timing is set to the crank properly?

advancer index pin on end of cam at 12 o'clock
crank on LT
 

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Discussion Starter · #5 ·
Hey guys, thanks for the replies/help.

My compression is real low.
Left: ~90
Right: ~60

On compression stroke with crank at LT, index pin is at 6 o'clock. Is this normal?
A full rotation on non-compression stroke and crank at LT, index pin is at 12 o'clock.
Cam sprocket shows "L" when index pin is at 12 o'clock.

Attached pics.
index pin at 6: IMG_2400.JPG
index pin at 12: IMG_2403.JPG
index pin at 12, sprocket at "L": IMG_2406.JPG
 
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