My bike gave me the bird today

4 replies to this topic
  • 450_gal

Posted March 22, 2008 - 04:14 PM


So, my husband and I were on a ride today. This is my first ride since adding a PMB spark arrestor.

I felt like there was a little power loss when we were riding by the roads, getting to the trails.

As soon as I shifted up into third and started to drop the hammer, I noticed a substantial power loss. After about five minutes of running the bike, I had it up into fourth and was getting ready to go up a hill, so I shifted down into third. As soon as I did this. My bike completely stalled. I shifted down to second and it sounded like the engine hit one stroke and then it died, locked up, and I was stuck sitting on the trail.

We checked my gas flow, that was good. We checked my plug, that's fine. We checked my oil; checked fine too.

At this point, we put it in neutral and rolled as far as we could, then bump started the bike and rode the couple of miles home. After bump starting the bike, there was a substantial loss in power in 1st and 2nd, as soon as shifting into 3rd, the bike wanted to die. There was a definite bogging sound. we're home. Pulled the magnetic drain plug and there's a chunk of metal stuck to it. It doesn't look like a piece of a gear tooth; it looks more like a flat piece of metal.

Also, when we got home, I looked at my new endcap and all the rivets, but four, are sheared off the pipe.

Any ideas?

I'm not even sure where to start.

  • MaxPower

Posted March 22, 2008 - 04:55 PM


[COLOR="Green"]you have compression?
metal in the filter?
Did you try it without the new spark arrestor?
Does it kick over in the garage without making any noises?

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  • sirthumpalot

Posted March 22, 2008 - 05:02 PM


Any story that includes "locked up" should unfortunately be followed by a disassembly to see what happened. Keep your eye on things such as the timing to make sure it's correct while you disassemble (did the cams spin in the sprockets), etc..

  • grayracer513

Posted March 22, 2008 - 09:18 PM


Check for compression at normal levels, then check for a sheared flywheel key by comparing the TDC mark with TDC as found by using a pencil against the piston crown. Also check for muffler packing blocking up the spark arrestor.

Then, start into it. But analyze things as you go Check the cam timing before you pull the cams, etc.

What you might well find is a failed connecting rod bearing.

  • TahitianRed

Posted March 22, 2008 - 09:34 PM


I would definitely have a talk with the previous owner.

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