Yamaha blaster won't shut off

[Blakely]

I recently just put my 1998 Yamaha blaster back together after putting a new top end in it and started it up for the first time and it just starting revving up super high so I hit the kill switch and pulled the key but it wouldn't turn off I pulled the coil off the spark plug and it just kept going. I ended up having to turn the fuel off for it to finally shut off. I have no idea what could cause this any ideas?

 

[Slydog]

I recently just put my 1998 Yamaha blaster back together after putting a new top end in it and started it up for the first time and it just starting revving up super high so I hit the kill switch and pulled the key but it wouldn't turn off I pulled the coil off the spark plug and it just kept going. I ended up having to turn the fuel off for it to finally shut off. I have no idea what could cause this any ideas?

Probably had an air leak that raised the cylinder temp way up. If the plug gets that hot it can ignite the fuel without the need for the coil wire like you just found out. Hopefully nothing got damaged
You should do a leakdown test. And check throttle operation

 

[DLStryker]

I believe they call it dieseling.

 

[Larry's Shee]

For future reference, to those that might read this, pull clutch, hold both brakes, shift into 2nd, dump clutch to stall. Shutting fuel off takes to long to kill it, and will damage it before it quits

 

[Slydog]

For future reference, to those that might read this, pull clutch, hold both brakes, shift into 2nd, dump clutch to stall. Shutting fuel off takes to long to kill it, and will damage it before it quits

Thats really good advice for those that don't know. It can save your engine

 

[Blakely]

For future reference, to those that might read this, pull clutch, hold both brakes, shift into 2nd, dump clutch to stall. Shutting fuel off takes to long to kill it, and will damage it before it quits

I wish I had a rear brake the quad didn't come with a cable or caliper when I purchased it

 

[Larry's Shee]

I wish I had a rear brake the quad didn't come with a cable or caliper when I purchased it

Then hold front brake, sit towards back and pray

 

[blaster214]

Most likely a left side stator side crank seal base gasket or reed gasket that leaked causing the extreme lean condition. Hopefully it didn't melt down the new top end although it probable that it did.

 

[Slydog]

Then hold front brake, sit towards back and pray

Or have the front against something solid
Do a leakdown test to confirm where leak or leaks are before disassembly

 

[Slydog]

Then hold front brake, sit towards back and pray

Or have the bike against something solid. All jokes aside. You need to do a leakdown test and find your leak or leaks. The above mentioned are very common air leak areas. It needs to be fixed before firing it up again. Hopefully no damage accourred