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Discussion Starter · #1 ·
Just purchased my first bike 2 weeks ago and have yet to ride it. She won't rev past 4000 and if you force her she dies. Getting some smoke out the pipes inconsistently but more so at higher rpms. Still waiting for a clymers to arrive in the mail but thought you guys might be able to help. Does this sound like a carb issue or ignition issue? Oh yeah its a 71 CL350.

Where do I start?



Thanks, Sarah
 

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Sounds to me like the carb slides are not lifting like they should, Alot of times the diaphragm will tear. I have also seen them (carb tops) put back in with the slide spring all cadywomp, wich will not allow them to travel up. Easy inspection just pop the top off yor carbs and take a look, if its been sitting for a while make sure they are free from varnish as well.
hope that helps
 

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Discussion Starter · #4 ·
Thanks. I'll check the carbs in the AM. And see if anyone has a compressor gauge I can use. I'm sure I'll be back with more questions. Thanks for your answers for now.
 

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Discussion Starter · #6 ·
Yes - I did have the engine warmed and the choke off. :(

I checked the diaphrams and springs - nothing was torn and the spring was all straight and normal (assuming that's the opposite of cadywomp).

I guess I will see if I can get the compression read next.

Let me know if I should check anything else while I'm exploring.


Thanks, Sarah
 

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Discussion Starter · #7 ·
So I checked and have compression, but I need to go buy a reader still to get the numbers.

When I removed the spark plugs - they seem to be carbon fouled. I'm also trying to get the air filter case off to look at that....

Any other suggestions?
 

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Discussion Starter · #9 ·
Okay. Today I decided I'd go start her again. I was told by the previous owner that she rode just fine before shipped here. So I have hope its a simple fix.

Today - with the choke on - she revs as much as I want her to without fail. That's a good sign. But as soon as I turn the choke off... she bogs out at 4000 - 4500 rmps.

Should I adjust the carbs? Starting with what? Maybe dirty main jet?

Help please!
Thanks!
 

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Sensei
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Not to say this is your problem, but, some members have mistaken the choke positions and were actually closing the choke when it should have been open... SO, just to be sure, the choke is CLOSED (on) when the lever is UP (horizontal), and OPEN (off) when the lever is down (vertical)..... I think the confusion comes from the fact that the actual choke plate position is the opposite (90 degrees off from) the lever.....(open when horizontal, and closed when vertical)
Typically, with the choke on (lever horizontal,plate vertical) the engine won't be able to "breathe" enough at higher revs, and will be too rich, fouling the plugs (sooty/carbon fouled or wet/gas fouled).... ;)
 

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Sounds to me like 66Sprint is onto something there. Make sure you follow his directions. If you ever forget the on/off positions, there is an arrow, and the word "Off" stamped into the metal of the choke lever. Rotate in the direction of the arrow to shut the choke off.
 

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This is what I would do if it was in my garage. Pull the carb bowls and make sure there are clean and the jets are still screwed in. I had one jet that was laying in the bowl when I bought mine. Pull the fuel lines at the pet cock and spray some carb cleaner down each line working the throttle a little bit as this works surprisingly well on motorcycles to clear minor clogs. Pull the plugs, clean and replace or replace if needed. Start the bike when cold with the choke as needed and reach down with both hands on the cold exhaust pipes and feel if the both warm up evenly, doesn't take long. DONT burn your self, pull your hands when they get hot and this only works on cold pipes!!. I guess you could use one of those fancy digital laser surface gauges if you had it. When I got mine the right pipe was barely warming up and I could leave my hand on for almost a minute. Then when the pipes are warm feel walk around back the exhaust pressure for balance. Then turn it off and pull your plugs again and inspect for fowling from oil or gas.

I was able to identify the right cylinder was an issue for me as it was not heating the header, had little exhaust pressure and the plug was soaked with gas. Luckily I had good spark so that was not an issue . This was supported by the smell of gas in the oil also. Cleaning the carbs a little, fixing the jet and balancing the carbs helped my bike a ton. This may only rule out some other issues for you but will get you going the right direction and give you something to do until your manual arrives. If you have gas, good compression, spark and timing, it will run well.

Good luck and don't burn your hands.
 

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Discussion Starter · #13 ·
I think the choke might be the issue. Mine says Open with an arrow pointing to the left - which pushes it vertical. . . Which in my head was opposite of you described it....

That would explain it all! I'm going to go test again... You just made my night! :D
 

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Discussion Starter · #15 ·
Crisis averted.

Thank you so much for your help, everyone. So glad it turned out to be as simple as me thinking backwards. :?

Glad everything is okay, and I'm off to ride tomorrow! :cool:
 
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