IS IT SAFE TO RUN MY 660R WITHOUT THE SPARK ARRESTOR? IF NOT PLEASE EXPLAIN.
THANKS FOR ANY INPUT.

 

If you take your spark arrester out, you will need to re-jet both carbs to compensate for the open exhaust. If you don't re-jet the carbs you could lean the air-fuel mixture and ruin the engine.

 

Yes. It's not going to hurt anything. The spark arrestor is there primarily to stop sparks from the exhaust from starting forest fires (hence the name) and to act as a muffler and quite things down. My dealer even suggested that I should take mine out!

But there are some good reasons to leave it in.
Mainly, in many state forests and other government lands, you are required to have a spark arrestor in order to ride.
Also, it might be too loud for you. But like a wise man once said, "If it's too loud, you're too old!"

Bandit99
'99 Banshee (gone but not forgotten)
'01 Raptor (Team Yamaha Blue)

 

SOMEONE SUGGESTED I SHOULD RUN IT FOR A SHORT DISTANCE AND THEN TAKE THE SPARK PLUG OUT AND SEE IF IT WAS WHITE ON THE END AND IF IT WAS PUT THE SPARK ARRESTOR BACK. IF WAS NOT WHITE IT SHOULD BE OK! IS THIS TRUE?

 

That is to make sure you're not running to lean (too much air, not enough oil = BAD). Running w/o the SA would let more air through, so definatly check this.

When you do check it, run the machine wide open for a few seconds, pull the clutch and turn it off. Coast to a stop and check the plugs right there. This will give you the best reading. Otherwise, you may change the color of the plugs while puttsing into the garage, making checking them pointless.

The perfect color is a nice clean tan.