Whooshing noise at high rpm's and possible overheat?

[Vikingimike01]

Take it apart and check the inside of the cylinder.

 

[crassius]

if it is surging at that speed, most likely cause is excess vibration - check motor mounts

 

[dparenti13]

Replaced the CDI with a new one I had around and it ran alot better at higher speeds. I fixed the chain rubbing completely. The bike runs good for a solid 15-20 mins then I let it cool down for 5 minutes before continuing. But normally at the end of my rides (30 mins total maybe) the bike starts misfiring, shaking back and forth and when I pull the clutch in the bike stalls. It starts right up again if I let the bike cool down. Also I noticed after coming off the throttle after being at high rpms, the engine runs kind of rough. Not really sure whats causing all of this...

 

[Frankenstein]

Replaced the CDI with a new one I had around and it ran alot better at higher speeds. I fixed the chain rubbing completely. The bike runs good for a solid 15-20 mins then I let it cool down for 5 minutes before continuing. But normally at the end of my rides (30 mins total maybe) the bike starts misfiring, shaking back and forth and when I pull the clutch in the bike stalls. It starts right up again if I let the bike cool down. Also I noticed after coming off the throttle after being at high rpms, the engine runs kind of rough. Not really sure whats causing all of this...

Wasn't there a cdi heating up issue that could be causing this type of problem? They warm up and get funky, unless this has been happening before the cdi swap.

 

[dparenti13]

Yeah, my cdi is mounted fairly close to my exhaust and head, should I try relocating it? Both CDI's have had this issue, but the bike overall ran better before it heated up.

 

[crassius]

that heat problem was mags internally arcing due to loose rivets or loose ground

there was an air leak earlier in this thread, so may be just motor overheating

 

[dparenti13]

that heat problem was mags internally arcing due to loose rivets or loose ground

there was an air leak earlier in this thread, so may be just motor overheating

I don't think I have an air leak, it idles fine when I start it and the spark plug is a nice tan color. What is this internal arcing, and how can I fix it?

 

[gary55]

The chain thing is total bulls**t. The vibration thing is highly possible, but generally that causes a oscillating speed up slow down speed up slow down cycle without the engine dying and no change in throttle position. I'm leaning towards CDI just on account of the misfiring.

 

[TruewoC]

I've had this problem before and found out it was the spark plug. once the spark plug gets over a certain temp it stops firing. i recommend you go replace the cheap Chinese spark plug with some ngk plugs

 

[dparenti13]

I've had this problem before and found out it was the spark plug. once the spark plug gets over a certain temp it stops firing. i recommend you go replace the cheap Chinese spark plug with some ngk plugs

Already have an NGK, its a B8ES i think... is that too hot of a plug?