No bottom end power

This topic has 4 replies, 3 voices, and was last updated 11 years, 4 months ago by Bruce Woodrow.

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- March 30, 2015 at 6:23 pm #45084
  
  tony zambos
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  Aaron,
  Just because you’re using the jetting other people told you to use does not equate to having the proper jetting, unless you have the same weight floats, at the same height as the other people. Pull the plug and check its color and also check the color of the exhaust header. Also check the packing in the exhaust pipe.
  With a Rotax, you can’t slam the gas pedal down coming out of a turn. Other causes could be the wrong gearing or maybe it’s time for a rebuild
- March 31, 2015 at 8:46 am #45122
  
  Bruce Woodrow
  Participant
  
  Aaron,
  
  Also, assuming that you running a ‘senior’ engine – check the power valve. If the power valve is stuck open, the bottom end power will be terrible and then be OK from about 7500rpm up.
  
  Bruce
- March 31, 2015 at 9:51 am #45132
  
  Aaron Smeenk
  Participant
  
  Bruce,
  
  That’s one thing we’ve thought about and after we did the rebuild we cleaned the power valve blade off. I’m not sure how to check if its working correctly though. I do feel like the kart has great top end power though
- April 2, 2015 at 6:22 am #45281
  
  Bruce Woodrow
  Participant
  
  Aaron,
  
  Once you have made sure that the power valve is moving freely, you can check that it is closing by removing the exhaust from the cylinder ‘socket’ and looking in through the exhaust port – the blade of the valve should close off quite a lot of the port and be pretty close to the piston when the power valve cover and spring are fitted.
  
  Bruce
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