66cc porting

Discussion in 'Performance Mods' started by Amberly Spellend, Oct 21, 2011.

  1. Amberly Spellend

    Amberly Spellend New Member

    i just got my engine to today and all ready have it striped down anyways i have shaved the head to the fin and bump it up by 1.7 points

    anyways as far as porting

    i want to port for more power low end power so would that mean i would want to make them a bit wider and not thouch the port timming :-/

  2. Neon

    Neon Member

    I could be wrong here and i'm sure someone will correct me if i am. Porting increases midrange and topend not bottom. Shaving the head will get you your increased bottom or torque. You have already done that though. Go ahead and port if you want to. It's always a good idea to at least port match if you can.
    Last edited: Oct 22, 2011
  3. Amberly Spellend

    Amberly Spellend New Member

    Port matching ?

    what else can be done to this engine ?

    Would you recamend porting a little bit ?
  4. Amberly Spellend

    Amberly Spellend New Member

    I got a stock kx65 pipe i am thinking of modding to fit the 66cc

    would that be a good idea ?
  5. Neon

    Neon Member

    Port matching is making sure the intake ports open at the same time. they are the two ports on the side of the cylinder. if you can get a side on a circle. If you can get the kx65 pipe to fit give it a shot i'm not sure what it would do, but why not? There is a lot to be done to these engines, but the thing i would do first and foremost is replace the bearings and seals with better quality ones. you can either order them online or take them in to a local bearing and seal shop. They can match them up with better quality one's.
  6. jaguar

    jaguar Well-Known Member

    these are things you can do for better low end power:
    change the transfer ports so that the fuel/air is directed more towards the rear of the cylinder.
    Use my formulas to determine if the ports need to be widened or changed in their height.
    Lower the head for more compression (or shave metal off the bottom of the cylinder).
    Buy a good carburetor that will atomize the fuel better for better combustion.
    Buy the CDI/coil from JNMotors and throw the stock junk far far away.
    Pipes; best is the torque pipe I make. Second best is any other pipe as long as you experiment until you find the optimal distance from the motor for best low end power and best top end speed.
  7. Amberly Spellend

    Amberly Spellend New Member

    so what would wideing the ports do ?
  8. Amberly Spellend

    Amberly Spellend New Member

    would you say it would be a good idea to raise the ex port and lower the in port for long distance riding ?
  9. max350

    max350 Member

    Hello! Before you start trying to tune your engine. build your bike, run with the original engine. when you get tired of it, try to read everything you can about the two stroke tuning. As you ask quite elimentära questions so I assume you have no more knowledge in this area, my advice run the original engine and have fun
  10. Amberly Spellend

    Amberly Spellend New Member

    im building an all around bike that will hopefuly do 50mph and ride at 20mph at vary low rpm and not make a racket

    but im gong to do this in one shot so i want to do this right

    so for porting

    what dose widing the ports do ?
    Last edited: Oct 25, 2011
  11. Neon

    Neon Member

    What is it with kids trying to kill themselves these days? The best advice anyone can give is to wait a year buy a "real" motorcycle, go take your road test and prove you can actually handle yourself. That way you can cruise at 20 or 50 all day long if you wish. You won't make a lot of noise either.
  12. Amberly Spellend

    Amberly Spellend New Member

    i have a 1997 cr500 with a overshaved head and a bored jet running running 95%methol and 4% nirto and 1% water with 40:1 castor in the mix pushing 140 hp and i race 125s

    i do not think a bicycle can be something i would have a problems with how ever hydro v breaks are thouchy

    could someone please help me with the porting
    Last edited: Oct 25, 2011
  13. Neon

    Neon Member

    You are talking about completely different worlds here.
    That is a motocross racing bike.
    Playing in traffic is completely different. Smash into the back of a car, or have a car rear end you and you'll understand. A bicycle is completely different.
    You should also pay more attention to your spelling. Don't know what "nirto" is. You probably mean methanol not "methol". Touchy not "thouchy". Never heard of hydro v brakes. Heard of hydraulic v brakes though. What's the 1% water for, to make the engine run rough. Good to see you found something that will stay mixed in with an alcohol based fuel.
    I believe people have already tried to help you with porting. wouldn't hurt to read them again, Or go learn some basic engine tuning and actual terminology.
    Last edited: Oct 25, 2011
  14. Amberly Spellend

    Amberly Spellend New Member

    water in alcohol based fuals stops it from pinging and alowing for better conpression and nitro content

    i run 19.5:1 and at 5% nitro with 1% water

    sorry about my spelling but i fractured my arm 3 days ago and im slighty high on meds
  15. Amberly Spellend

    Amberly Spellend New Member

    All i want to know is.

    1) What dose widing the ports do ?
    2) I now want mostly mid range power so how much should i change the port timmin?
    3) would you recommend any porting ?
  16. max350

    max350 Member

  17. Abeagle

    Abeagle New Member

    mountainman_oef likes this.
  18. lazylightning@mail.r

    lazylightning@mail.r Active Member

    Hi Amberly!

    Look, that Jaguar fellow has a link at the bottom of all his posts. If you navigate to it, you will find a porting section. http://www.dragonfly75.com/motorbike/timing.html

    Here is the whole list of mods he suggests: http://www.dragonfly75.com/motorbike/index.html

    Is that nitromethane or nitroglycol you running in the motobike mix. I think a 95% alchohol mix would fry one of these little cChinese babies. I've thought about the nitromethane thingy though...and anti-ping or other octane boosting modifications to the fuel mix. Any ideas?

  19. lazylightning@mail.r

    lazylightning@mail.r Active Member

    Now I see. Methanol is usually mixed with nitromethane.
  20. mountainman_oef

    mountainman_oef New Member

    Holy crap... this is amazing....if anyone is serious about squeezing everything out of your ht engine this is way to do it....Thank you so much for sharing this..