I have a raw engine which was running fine at 30 + mph but over the past week it tops out at about 23-25 mph it also is not reaching as high of rpm's I noticed some oil around the air filter please help
i would check my gaskets if you haven't already replaced them. and the oil around the air filter may be leaked gas that collected dirt, it was for me anyway. are you running the right mix? oil tends to settle after a long time and it may have gone down your tube, it may be a while b4 it runs out but it wont hurt the engine.
Has it backfired on you? If it has,as a last resort, pull the head off and look for scratches on cylinder lining. If your losing power you maybe losing compression. Where you riding on wet roads? If you where, pull the head off and look for damage.
no i dont have a pic of the pipe. but it is a black solid pipe with a little hole at the end the whole thing is welded together from the factory. i have changed the plug. tried ajust on carb could it be the kill switch? i took the pipe off and ran it for about a block and noticed a dramatic increase in power and top end. please help.
You said you get a dramatic power increase running with no muffler. You can get a replacement from most of the suppliers. Or, do as David suggested and grind the welds off the end.
If it is totally welded up it may be a (badly) repaired muffler. It would not surprise me to find a repaired part in a kit if, say, revolution was low on parts. It is rare but not unheard of.
Why don't you try this: Remove it and (using a piece of rubber hose if you don't want black lips) blow through it from the manifold end. Any obstruction?
My muffler (chrome) is short and fat compared to the one in your pic.
The thing about plugged mufflers is the engine usually won't start if they are plugged. An old wedding reception trick is to stick a potato in the groom's tailpipe(s). No man, on the car! It won't start. Easier than trying to remember which plugs the wires went to.