Blaster Disaster - Base Blow Out

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-Blaster Disaster-

Base Blow Out

The Question - I was riding my 1998 blaster on ice a few weeks ago. I guess I was reving it high in 3rd gear. The base gasket blew, the piston and rings burnt up and it scored the cylinder. It cost about $150 to get the cylinder bored and for new piston, rings and gaskets. That did not include the labor, I did that myself. So I'd say yes 2-strokes are not meant to be ran with high rpm's and from what I hear they are more of a race bike. So from experience, put your bike up for sell if you like to ride in mud, on ice or run it the least bit hard.

The Response - If you blew out the base gasket on that Blaster I doubt it was because you were revving it too high, more than likely it was because no one performed a leak down test on the motor before you went racing. You may have noticed a air leak in the motor with a leak down test before that ever happened.

The Blaster motor has a short stroke and therefor makes it able to rev very high without fear of failure due to over-rev. As high as a Banshee (9000 to 10000 not impossible). Though it's air cooled it'll still turn those kind if revs. Usually the pipe, ignition or porting will shut down any rpm increase before the motor is actually over-revved.

A two stroke motor will rev WAY higher than a 4 stroke, and more reliably at those revs. For a 4 stroke to even come close to the power output of the same displacement 2 stroke it has to turn in (almost) as many power pulses. Try turning a 4 stroke 22,000 RPM. Very few are made that way (I'm thinking Honda NR500 mid 1980's). Remember the motorcycle Freddie Spencer was riding in the 500 GP's during those (crummy for Honda) years? It revved so high it even sounded like a 2 stroke.

Rick

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Base Blow Out
The Question - I was riding my 1998 blaster on ice a few weeks ago. I guess I was reving it high in 3rd gear. The base gasket blew, the piston and rings burnt up and it scored the cylinder. It cost about $150 to get the cylinder bored and for new piston, rings and gaskets. That did not include the labor, I did that myself. So I'd say yes 2-strokes are not meant to be ran with high rpm's and from what I hear they are more of a race bike. So from experience, put your bike up for sell if you like to ride in mud, on ice or run it the least bit hard.
The Response - If you blew out the base gasket on that Blaster I doubt it was because you were revving it too high, more than likely it was because no one performed a leak down test on the motor before you went racing. You may have noticed a air leak in the motor with a leak down test before that ever happened. The Blaster motor has a short stroke and therefor makes it able to rev very high without fear of failure due to over-rev. As high as a Banshee (9000 to 10000 not impossible). Though it's air cooled it'll still turn those kind if revs. Usually the pipe, ignition or porting will shut down any rpm increase before the motor is actually over-revved. A two stroke motor will rev WAY higher than a 4 stroke, and more reliably at those revs. For a 4 stroke to even come close to the power output of the same displacement 2 stroke it has to turn in (almost) as many power pulses. Try turning a 4 stroke 22,000 RPM. Very few are made that way (I'm thinking Honda NR500 mid 1980's). Remember the motorcycle Freddie Spencer was riding in the 500 GP's during those (crummy for Honda) years? It revved so high it even sounded like a 2 stroke. Rick