Overflow tank cap popped of twice during riding

[fck55mph]

I have a 97 shee that runs fine,jetted perfect. Yesterday while riding, i noticed the coolant overflow cap popped off. Didn't think too much of it,put it back on and the coolant level was still fine. A while later, it had popped off again. It was not running hot nor has it ever been run hot or low on coolant. Would a bad radiator cap cause the pressure in the system to pop that cap off?? Just wondering if anyone has seen this before....Thanks for any input!!!

[VegasJeff]

I have a 97 shee that runs fine,jetted perfect. Yesterday while riding, i noticed the coolant overflow cap popped off. Didn't think too much of it,put it back on and the coolant level was still fine. A while later, it had popped off again. It was not running hot nor has it ever been run hot or low on coolant. Would a bad radiator cap cause the pressure in the system to pop that cap off?? Just wondering if anyone has seen this before....Thanks for any input!!!

I had mine pop off once and it was because I blew an o-ring on the dome.The overflow bottle has a vent

tube on there as well. maybe its plugged?

[KEVSWS6]

This is usually caused by a leaky head gasket or O-ring if you have a cool head. You likely have exhaust exiting your coolant system.

[fck55mph]

I will check the coolant bottle vent tube and go ahead and replace the head gasket. I think I have one in the garage. Thanks for the input guys and especially to Kevin...love the power you hooked me up with!!!