Author Topic: question for top end rebuilders  (Read 358 times)


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question for top end rebuilders
« on: January 15, 2020, 11:23:18 PM »
just looking at the cylinder and notices a small hole right at the top of the exhaust port .. is it supposed to be there? a friend who has a 2017 ser-300 ours id a 2014 ser-300 has the exact same hole in the same place!!! anyone enlighten me ??


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Re: question for top end rebuilders
« Reply #1 on: January 16, 2020, 12:11:37 AM »
This FINALLY answers my question ,since no one else could confirm  ::)
this hole is there for better starting. at slow crancking speed, this hole releases some compression to help the startermotor overcome too much resistance.
look in the exhaustport on the outside of the cilinder and notice where that hole ends up (above the powervalve)
once the engine's running this no longer has an effect.
thank you for posting this  ;D
cheers, Hannes.
« Last Edit: January 16, 2020, 12:13:21 AM by hannesd »