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Discussion Starter #1 (Edited)
Little less then a week ago I tried to fix a poogs syndrome, I removed the tank and checked the pet cock reassembled it and noticed a piece of the front carb wasn't plugged what I thought was not deep enough in the engine block, I removed one of the air intakes and put the carb in deeper. After taking it for a test spin I noticed it backfired like crazy around 5k rpm its so bad that the bike shocks with shots of power/no power when it does that (its mostly around 5k rpm) to fix this I just switched back to 4th gear and let it sit at 6k+ rpm until today where it did it even when driving slowly, the shocking is so bad you can't drive nicely when I pulled over I noticed the idle made jumps from 1k to 3k to below 500rpm for a while almost as if there isn't a good combusting. Shortly after it hit 0rpm and the engine shut down. Luckily I was at work and waited till I was done to see if it still had the problem. It didn't for about 5-10 min when I went off the highway to check it out, same problem. I waited a couple of minutes and drove home. Does any of you have any idea what this could be? Could it be clogged carb?


Edit: sorry for the crappy writing. I did this on my mobile phone
 

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Sounds like an Air leak between carb and intake.

Carb Boots have alignment marks to help you get them oriented correctly, clamps need to be snug
 

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I had the boot come loose from what I guess was the constant vibration. Idle went crazy while I was sitting at a stop light. I was holding in the clutch and it jumped to 3.5k. I’d be lying if I said it didn’t scare me. I managed to reseat it without shutting the bike.
 

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Try some water in a spray bottle, warm the engine fully and spray the boots while listening for changes in how it's running, and steam at the exhaust tips.
 

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I took it to mean a sudden burst of power, which points to dirty carb jets (but could easily be ignition), but the high rpm moments point to an air leak.

Should also check the vacuum line at the left carb, it should be dry at all times.
 

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Discussion Starter #10
By "shock" I assume you mean "shake".

Sounds to me like you have one cylinder cutting in and out. Possibly a carb issue but could be electric.
By shock I mean when driving you get a switch between power/no power about 10 times a second resulting in shocking acceleration/no acceleration, acceleration etc
 

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Is there a easy way to upload videos to a forum post, might be Easyer to show you
Upload to youtube, flickr, or maybe imgur, etc. Post link here.

Won't hurt to make sure the ignition coil connections are tight.
 

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Discussion Starter #14
I took it to mean a sudden burst of power, which points to dirty carb jets (but could easily be ignition), but the high rpm moments point to an air leak.

Should also check the vacuum line at the left carb, it should be dry at all times.
I noticed the vacuum line was sitting against the engine so it was melting. I think it's not melted all the way through though. I'll disassemble it to see. If not then that should not be the problem right
 

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Here it is

https://youtu.be/fcItzaRepEY

Note that so far its more likely it does this when heated. Even at idle speed. Which causes the bike to shut off if not keeping rpm above 3k
"Video Removed By User"

As posted earlier, sounds like two problems, by the description. Leaking boot after it heats up, clogged pilot jet.

Check the vacuum line from the left carb, should always be dry.
 

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I noticed the vacuum line was sitting against the engine so it was melting. I think it's not melted all the way through though. I'll disassemble it to see. If not then that should not be the problem right
\

Is it wet or dry inside the hose?

If it's wet, and also leaking vacuum, there's the rev issue.
 

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Discussion Starter #17
I noticed the vacuum line was sitting against the engine so it was melting. I think it's not melted all the way through though. I'll disassemble it to see. If not then that should not be the problem right
\

Is it wet or dry inside the hose?

If it's wet, and also leaking vacuum, there's the rev issue.
Is this considered wet?

And how would I fix this problrm if it is?
 

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Is this considered wet?

And how would I fix this problrm if it is?
I'd say yes, but only you can tell if that smells like gas and is wet. There should be no gasoline in that vacuum line, ever. If there is, a petcock rebuild is needed, and probably an oil change after it's repaired.
 

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Discussion Starter #19
Is this considered wet?

And how would I fix this problrm if it is?
I'd say yes, but only you can tell if that smells like gas and is wet. There should be no gasoline in that vacuum line, ever. If there is, a petcock rebuild is needed, and probably an oil change after it's repaired.
I would say that it doesn't smell like gasoline. Where would it come from? I've removed all the tubing and the only tube that has this is coming from the rear cylinder and only at the connection point.

Also looked at the petcock vacuum seal. And I would say it could use a replacement.
 

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Discussion Starter #20
Here it is

https://youtu.be/fcItzaRepEY

Note that so far its more likely it does this when heated. Even at idle speed. Which causes the bike to shut off if not keeping rpm above 3k
"Video Removed By User"

As posted earlier, sounds like two problems, by the description. Leaking boot after it heats up, clogged pilot jet.

Check the vacuum line from the left carb, should always be dry.


With vacuum line from the left carb do u mean the small tube in the Pic? No that's dry.

Sorry I tested the vacuum line coming from here (second Pic)
 

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