Any chance your throttle cable could be getting hung up and pulling on the throttle when your turning hard?

I asked about the idle because no matter what I adjusted mine would never idle.

 

naw its not the idle i had the air filter off one time and when it started revin hard i checked that and the slide was closed

 

Take a can of WD40 with the straw on it and spray it around the carb boot and case. While doing this, push and pull on the carb and see if it changes speed. Look for cracks in the boot and hoses.

 

If you are looking for sound advice about jetting, read this. It's a PDF file, so you'll have to have Acrobat Reader to view it. The erradic rpms are caused by an air leak somewhere. Check the carb boot, reed cage gasket, and cylinder base gasket. Of the 500s I've seen with this problem, most had a blown base gasket, on the transfer ports between the cylinder studs. The span is fairly long and the clamping force is not high there, so the gasket can blow easily. If it is a base gasket, use a compound like Gaskacinch when reassembling the engine. That will help strengthen the gasket. Good luck.

 

My Rm125 does this a little but only when idling it doesn't affect the running. My 1986 rm comes stock with flat slide mikuni carb. These carbs have a lot of screws and gaskets on them the whole slide bore can be dissasembled on my but you need torque drivers and all kinds of wacky tools to take it apart. My carb is always wet at the seems of these gaskets... time for a carb kit. I think this is why my bike idles eradically because its sucking a little air hear and there. I don't know much about the zilla's carB or if your's is stock but maybe thats the problem. Spray some starting fluid around your carb gaskets as well and if it starts to rev... then you can locate the leak. I did this on my 87 Trans Am when I found out the intake was sucking air below my fuel injection. Now the check engine light doesn't come on and the car doesn't idle erradically and stall.

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