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Discussion Starter #1
'73 CL350 here. Trying to get this thing running well.

Rebuilt the top end this summer. Less than 100 miles on it, and it has never ran quite right. Starts up really easy (almost too easy...) and idles like a champ. However, from 3-5K rpm it hates life. Sluggish and not smooth at all (as if a cyl is dropping). Above 5-5.5K it seems to smooth out. Valves are adjusted, timing was bang on (and advance seems to work as it should with a strobe). Here my summary of troubleshooting.

- Valves done
- Points timing done
- New coils/HT leads/plugs
- New intake boots
- Throttles sync'd
- Carbs ultrasonic cleaned and blown out. Looks like 115 mains and 68 secondarys? AF set to 1.25 out. Floats @ 26mm (722a carbs)
- Unfortunately, I am running aftermarket mufflers (w/ baffles) and pod filters (no airbox). Pods are pretty big and don't block the 2 air inlets in the intake.

Here are the plugs (L&R in order). I noticed in the problem rev range if I pull the right HT lead, the bike will run worse, but if I pull the left lead, the bike wants to die. Looks to be running rich on the R side?
 

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Discussion Starter #2
A thought I had this morning... I remember when I was first digging into these carbs in the spring I came across an odd thing... the volume between the slow jet and the plastic cap was stuffed with aluminum foil in both carbs. I found it really odd at the time, but maybe it was a janky way to lean it out?


 

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That is a repair technique with which I am totally unfamiliar.

It does appear that the right side is running pretty rich. When one side is different than the other there pretty much has to be something along the lines of a float that isn't floating or is mis-adjusted, a float valve that isn't sealing, possibly a restriction in the air passages in the carb, any of at least a handful of other stuff, but it's not the jets being the wrong size.
 

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Discussion Starter #4
That is a repair technique with which I am totally unfamiliar.

It does appear that the right side is running pretty rich. When one side is different than the other there pretty much has to be something along the lines of a float that isn't floating or is mis-adjusted, a float valve that isn't sealing, possibly a restriction in the air passages in the carb, any of at least a handful of other stuff, but it's not the jets being the wrong size.
...any of at least a handful of other stuff...
Is exactly my issue :p I can turn a wrench well enough, but for whatever reason, carbs have always been the bane of my existence.

Both floats were set to 26mm by me (they were 23 or something before). Float valves seat (I can't blow through inlets when inverting the carb). I noticed this float was a bit dented, but when shook, there was no gas inside.

I may have another set of carbs in a box somewhere. At least to narrow it down a bit...
 

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Discussion Starter #5
Ordered a pair of jet kits from CMC. Who knows how someone in the past 40 some years molested those carbs/jets. Hopefully that fixes it!
 
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