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Discussion Starter #1
Got my CB back from the shop for the second carb cleaning. Thing was running ok for a bit. Not great very rough felt some flat spots in the rev range but when the rpm's built it smoothed out. Mechanic told me that the idle circuit on carb on is partially clogged like someone was trying to clean it out and broke something off in there. That air mixture screw was missing and is installed. When the mechanic test road it he said it ran ok and would die if you hit the throttle too hard but was rideable. So the bike was running and got up the road. I pulled into the gas station to fill up. Then then bike wouldn't go anymore. It just died when I tried to put it in gear and move. It still idled. I couldn't get it to ride a foot further without choking it. After I chocked it I got it going and turned off the choked because it didn't ride at speed with the choke. So at lights I chocked it and on the road I turned the chock off and got it home. I am going to pull the plugs and see what they tell me but I think I might need new carbs or re jetting. Any other bright ideas would be appreciated.
I know I am a retard for not buying a bike that ran well in the beginning. I'm kicking myself in the ass everyday for it.
 

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Discussion Starter #2
Oh yeah and this mechanic put brand new plugs in so maybe that is why the jetting could be suspect the performance worsened as the plugs fouled?
 

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I'm sorry, but your mechanic sounds like he doesn't have a clue about your carbs. Don't kick yourself in the ass. This an opportunity for you to get in there and learn what makes those carbs work. GET A FACTORY SERVICE MANUAL!
Here is another thought. Maybe somebody here has a set of proper carbs for that bike that you can buy. Get that thing up and running.
Take the old carbs and find somebody here who knows them inside-out, and get them serviced correctly.
As Yoda might say, "valuable knowledge here to be learned,,,, you will."
 

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Seem to remember this guy doesn't want to work on the bike at all....
 

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Is this the same spot you took it to the first time around? Weren't they supposed to have cleaned your carbs initially? And he still found shit busted or missing? I hope this guy is paying you...
 

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Discussion Starter #7
No this new guy very good clean. Took pics and fixed last guys clean. Bike ran good for a few miles. Maybe not good good but ok. Then it went downhill at the gas station. Mechanic asked me if I put diesel. Old school Jardine turn out pipes with stock airbox. A proper chop test is performed by getting on the road and getting up to speed then closing the throttle and finally killing the bike after engine braking for a bit? Is that the gist?
 

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Discussion Starter #8
BTW Jag what are you bored? Just go around after me posting that I don't want to work on my bike? Must be nice to have that kind of time on your hands. Can I borrow some? Then I might be able to wrench a little more.
 

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Discussion Starter #9
BTW Jag what are you bored? Just go around after me posting that I don't want to work on my bike? Must be nice to have that kind of time on your hands. Can I borrow some? Then I might be able to wrench a little more.
 

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Nope not following you around here...sorry

In your other threads you were given info, ideas and manuals from myself and others.

I'm kind of lost as to what you want.
YOU need to read the manual and try and understand how your bike works then figure out what it needs. Taking it to a bunch of shitty shops will not help.
Might have some luck if you find a shop that works on old bikes only

But maybe this is a fresh leaf for you
Let's start at the basics.
What's the compression in the motor?
Motor is timed 100%?
good spark?
How old is the fuel?
Seem to remember something about a different set of carbs on your bike? If so what year are they off of?
Carbs syced?
Pods?
Have you pulled the plugs? Do you know how to read plugs?
 

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Also what jets are in the carbs?
New seals in the carb?
What are the floats set to?
Floats tested to see that they float?


I'm going to assume that you don't know the answers to alot of that because you didn't do the work and it's hard to get that info from a shop.

It's a game of telephone from the bike to the shop to you then to the interwebs
 

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plug chop is getting it up to speed WOT in a higher gear, hitting the kill switch while pulling in the clutch. come to a stop (you can use the brakes) and pull all four plugs. read them for color.

my CB350 manual gave me a color chart and diagram to diagnose situations.....your 750 manual prolly does the same.

tex
 

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Color charts in manuals are there to show what a plug looks like under gross conditions. They don't show you what a plug looks like when you do a plug chop.

But if the plugs come out all black and fouled it gives you some indication. In a plug chop, the tips should basically have just the slightest color, if any. Mixture is read down inside the plug.

What year CB are we talking here? SOHC motors will splutter or die if you bang the throttle wide open at low revs. DOHC motors should be OK but that's how bikes with slide carbs run. They can't take WOT at low revs.

The fact that it ran OK for a while and then needed choke suggests that debris has clogged the pilot jets again. I'd rain and clean the tank and petcock filters and fit an in line fuel filter
 

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Flat spots mean either your accelerator pump isn't working or is working too well. To test, take the carb rack off and hit the accel pump manually. If it squirts then it works.

What does the inside of your tank look like? All the carb cleaning in the world isn't going to help if you are putting fresh junk in there because your tank is rusty.
 

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Discussion Starter #15
A fuel filter was installed when the carbs were cleaned by the second mechanic he is a good mechanic by the way not some cheapo like the first one. Also the gas that was in it was fine it is only after a longer ride and I put fresh gas that it started running strange. Also the bike runs worse as it warms. Of course I don't have the right wrench for the plugs so I need to get that before I can pull them out.
 

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You mean those plastic little filters? Yeah, not doing much except maybe getting clogged up when the fresh fuel stirs up the crap in your tank.

So, I ask you again (and this time answer the fucking question) what does the inside of the tank look like?
 

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Discussion Starter #18
Here is the story the plugs told.
Cylinder one is running lean. But not too bad looks ok actually. This is the carb with the idle circuit blocked almost completely. Compressed air and a 14 hour soak in hardcore carb cleaner did not clear this circuit it is looking like something is jammed in there. That is cylinder one.
Cylinder two is running rich. You can still see the white of the plug core but barely.
Cylinder's three and four are very rich plugs were wet when removed and completely black.
These plugs are brand spanking new. I rode the bike about a 3 miles before experiencing a drastic change in the performance.
 
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