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Discussion Starter #1
I purchased my bike a few weeks ago and have come to learn that several aftermarket parts were installed on it. My main question is, how do I identify what kind of exhaust did the last guy install? The bike backfires quite a bit and have been told that I need to re-jet my carbs. Do I need to know brand and model of my pipes to re-jet? Are there common locations for part numbers or any form of ID on pipes?


Thanks for the help!
 

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KK, for us to better help you out, you shoulg post a few pics of your 650 so that we can see whats installed. You may not need to rejet but rather adjust the PMS depending on what you have for an exhaust system. An other cause for backfiring is air leaks. Is your system tight? Post the pics and let's go from there.
 

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Discussion Starter #3
nope!!

I was just looking into that today. My intake manifold tubes are cracked in several places and actually move while the bike is running. I understand that will affect my air/fuel ratio and cause the bike to run lean which will affect the performance of the bike. That said, I think I still want to know what kind of pipes are on the beast so I can plan accordingly. I hope the pics help. Thank you.
 

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KK they look like Cobra dragsters. If they are, they should have a removable baffle and the Cobra logo some where near the end. That's a full system and would require rejetting but like you said the intake boots are cracked to the point of moving. I would start by changing them out, verifying the jets in the carbs for the proper ones and go from there.
 

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Discussion Starter #5
Corsair, thank you! I'll check for that logo when I get home. The baffles are removable( and the bike sounds horrible when they are out). I have the intakes on order and if the pipes are indeed cobra drags I'll order the jetting kit as well. Thank you for the help! And thought on removing/disabling the air injection system on the bike? We don't have emission checks where I live.
 

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Discussion Starter #7
Thank you nick57. I'm still researching everything I can on this thing. I'll take a look at the link you sent later and see what more I can learn. Thank you!
 
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