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head porting (how to?)

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LongMooie

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Discussion starter · #1 ·
ok i have some free time on my hands and untill i can afford to get a 70 head worked for my 50 id like to try to port my stock 50 head, ive looked but cant find and information can anyone help with info, photos, video etc



thanks
 
#4 ·
Well the key is obviously more air flow....so make sure your valves and springs are out and then get the intake gasket and scribe around the opening where theirs extra metal inside the gasket to see how much you can cut but dont do to much cause youll get gasket faliure......the object to opening the ports is not really to make them bigger but to clean them up and cut down on turbulence and alow the air to flow more smoothly because air doesnt like to turn corners or go around corners. Use an abrasive roll to cut it i recommend an 80 grit, but remeber just be patient or else youll cut to much
 
Discussion starter · #6 ·
klxrider245 said:
Well the key is obviously more air flow....so make sure your valves and springs are out and then get the intake gasket and scribe around the opening where theirs extra metal inside the gasket to see how much you can cut but dont do to much cause youll get gasket faliure......the object to opening the ports is not really to make them bigger but to clean them up and cut down on turbulence and alow the air to flow more smoothly because air doesnt like to turn corners or go around corners. Use an abrasive roll to cut it i recommend an 80 grit, but remeber just be patient or else youll cut to much
Click to expand...


sound simple enough! i know theres more that can be done thats not so simple but this is a good start thanks



i also read about the exhaust pipe outlet being drilled out with a tapered bit anyone have info photos would be great
 
#8 ·
i can see the needle files working well for a 2 stroke ports, but on a 4 stroke head you cant get the angles you would need to do a good port job. What is on thumper talk is more of a port clean up than an actual port job.



What you need to get is a dimond grinder bit and a drill or a dremel works well to. This will take material off much faster. Like others have said your dont want to reem the crap out of it so its giant. On a stock head going a little bigger is ok but not to much as the valves are so tiny as it is. Some people cut the guides while others dont think thats safe. Its all opinion.
 
#10 ·
LongMooie said:
ok i have some free time on my hands and untill i can afford to get a 70 head worked for my 50 id like to try to port my stock 50 head, ive looked but cant find and information can anyone help with info, photos, video etc



thanks
Click to expand...


Do you smoke ? If so port a little and blow in the port.
 
Discussion starter · #14 ·
50rider340 said:
i can see the needle files working well for a 2 stroke ports, but on a 4 stroke head you cant get the angles you would need to do a good port job. What is on thumper talk is more of a port clean up than an actual port job.



What you need to get is a dimond grinder bit and a drill or a dremel works well to. This will take material off much faster. Like others have said your dont want to reem the crap out of it so its giant. On a stock head going a little bigger is ok but not to much as the valves are so tiny as it is. Some people cut the guides while others dont think thats safe. Its all opinion.
Click to expand...
so how do i cut the valve guides while im in there?

We have burrs at work i have access too

Im not looking to go crazy as this is the first time i have attempted this type of engine work apart from building big bore engine, clutch kits etc etc...

i would like to do big valves but i think thats beyond my skill level



as i start ill post some photos as this might help anyone else thinking about doing the same to there 50 head
 
Discussion starter · #17 ·
Well its too late to turn back ive been hard are work in the garage ****ing around with the ports on the 50 head, ive never done porting before so i dont expect it to be up to par and ive most likely taken too much out or not enough but i gave it ago. i still have to take the head to work and wash it out and blow it out with the air line



comments welcome:)



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