Slant head orientation

Discussion in 'Heads and Cylinders' started by Jellyfish420, Jul 5, 2017.

  1. Jellyfish420

    Jellyfish420 New Member

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    I'm fairly new to the whole engine on the bike thing... But no stranger to engines. I have an 80cc and have done all the little things to it that you can do for free or very little money. Reaches 42mph with the stock 44t sprocket. Not to bad imo. For now I'm running the stock slant head and I've seen pics with the plug facing both forward and backwards...but can't find anywhere that says which way is better. Mine is facing forward... Bit seeing all these pics got me thinking that it may be better facing back as it would be closer to the intake and where the transfer ports face. Any opinions or actual facts anyone can share would be great. Thanks
     
  2. Dan

    Dan Staff
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    Howdy JellyFish, welcome!

    I've never thought about it. But ya got me thinking. 42 MPH is pretty amazing. Don't think I would bother trying to get any more out of her. But if ya wanted to, give it a shot. Keep notes on where, time and barometric/weather conditions.

    But am sure someone will be along who has tried it. Great thing about "here" Some amazing folks. Here is a thread on your question; https://motorbicycling.com/threads/which-way-spark-plug-slant.37384/

    There are a few more.

    But again, welcome!
     
  3. Chaz

    Chaz Active Member

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    Welcome to the forum. If you are hitting 42 mph with stock set up you are doing everything right.
    I don't think it makes much difference which way the head is oriented but it has been pointed out that the bigger fins should be at the exhaust port. Maybe it makes a difference if your ambient temp is high.
     
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  4. xseler

    xseler Well-Known Member

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    A few years back, I tried my angle head the other way........couldn't tell any difference. The angle would come in handy in certain bike frames that were a tight fit for the motor package.
     
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