Phantom85 falters at high rpms

TheSpeedyNeighbor

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I’ve been and currently am running 16:1 gas in my Phantom85. I got through my third tank so got my nerve up and and started gradually doing WOT runs for a short period. At full throttle or even 3/4 throttle the engine seems to falter. It kinda seems to turn off and restart when I slow down a bit after going WOT. I thought that my fuel was bubbling because of the vibration and I did some work on the bike and now it vibrates less so I don’t think that is the cause. My c-clip in my carb is in the middle position so I’m not sure if it’s running lean or if it’s right where it should be because it runs fine at lower rpms. The only abnormal thing that I can think of is my muffler. You may have seen my last post where half of my muffler cracked off. So basically I’ve been driving around with half a muffler (sorry DAMIEN). Would that cause the engine to be lean or behave like it is? I’ll add pics of the muffler just for kicks. Thanks…
 

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Post a pic of the plug, might be too rich and need to re-jet.
 
So basically I’ve been driving around with half a muffler (sorry DAMIEN). Would that cause the engine to be lean or behave like it is?
I think I was perfectly clear on your other thread about this problem...lol.

They are out of stock at the moment. Would it hurt the engine to run it with the pipe only? The part that fell off was just an extending straight pipe so I doubt it did much other than help decrease the sound but I’m not an expert.
Personally speaking I would NOT run a Phantom without the exhaust...These motors are made to run precisely with what they come equipped with and that includes its exhaust system which appears to me to have the perfect amount of back pressure for these motors.
The Phantom 85 motors can be very unforgiving if not run with the proper equipment that they come with as well as not following the 310 mile breakin proceedure to the letter.

Have you even called B-E.com for a warranty replacement for that exhaust system yet???

Ps...Also just as a side point...Breakin fuel/oil ratio is supposed to be 20:1 with the P-85s for the first 310 miles...Then NO LESS than a 25:1 after breakin is over.
 
I think I was perfectly clear on your other thread about this problem...lol.


Personally speaking I would NOT run a Phantom without the exhaust...These motors are made to run precisely with what they come equipped with and that includes its exhaust system which appears to me to have the perfect amount of back pressure for these motors
Technically I’m running half a muffler. I get where you’re coming from and I know I’m being a bit careless but come on. You can’t expect me to believe that every part was engineered like it was a Bugatti. It’s a Chinese bicycle engine with a larger piston and a few upgrades. Ignorant and naive I’m sure and feel free to prove me wrong but when it comes to these bikes an engine is just an engine as far as I can tell. B-E.com was supposed to send a replacement muffler but they had to back order it because they’re out of stock. I actually am doing 20:1 (6.4oz to one gallon). I made a mistake when I said 16:1.
 
Technically I’m running half a muffler. I get where you’re coming from and I know I’m being a bit careless but come on. You can’t expect me to believe that every part was engineered like it was a Bugatti. It’s a Chinese bicycle engine with a larger piston and a few upgrades. Ignorant and naive I’m sure and feel free to prove me wrong but when it comes to these bikes an engine is just an engine as far as I can tell. B-E.com was supposed to send a replacement muffler but they had to back order it because they’re out of stock. I actually am doing 20:1 (6.4oz to one gallon). I made a mistake when I said 16:1.
Would the lack of the exhaust pipe be the cause of my issue though? It runs fine at low rpm but at high rpm it bobs and weaves and acts like the fuel is turned off. I think it’s getting adequate fuel bc the carb is stock and the c-clip is in the middle position. I don’t think there’s a leak anywhere bc I replaced my gaskets and properly tightened everything down.
 
Technically I’m running half a muffler.
Technically NO, your not...You are running a piece of straight pipe with no muffler attached whatsoever, therefore no necessary back pressure, hence, if you keep running it like that, you deserve what you get for not heeding the fact that at least on either the Phantom or Avenger motors, that entire muffler assembly is absolutely necessary.

Do as you wish, it may not be a Bugatti, but the P-85 motors are the cream of the top when it comes to CG motors...If you wish to damage and or destroy it running it without the full exhaust, be my guest because it is your bike, not mine...lol.
 
I think I was perfectly clear on your other thread about this problem...lol.





Have you even called B-E.com for a warranty replacement for that exhaust system yet???

Ps...Also just as a side point...Breakin fuel/oil ratio is supposed to be 20:1 with the P-85s for the first 310 miles...Then NO LESS than a 25:1 after breakin is over.
I believe he didn't order from bicycle engines. If I remember right he said he ordered from elsewhere
 
I believe he didn't order from bicycle engines.
OH...Really???

 
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