Port and polishing

[monkeyballs]

Ok, well im taking off the top end from my ex and I would not minde doing a p&p. Just a miled one.. I will also be droping in a hot cam stg 1 and a wiseco light weight piston at the same time. I currently have a full system yosh pipe and a k&n air filter with a pre charger, running no air box lid. I think this thing should pull pretty hard since every thing is all set up for the p&p. What do you think?

Then if you guys think its 2 risky ill just stick with a polish. I was wondering whats the best way 2 do this.. I was thinking of just using a dremle for the p&p.. (canadian tire 36 piece rotary tool kit lol). Then some one told me to use a ball hone for the polish. But there are so manny sizes and types out there.. I have never done a p&p and I was wondering if some one made a wright up on it?

Thank you

Bracer Buechli

[ds268]

I don't want to bash on your mechanical/performance skills here but if you don't know what you're doing as far as porting, you can cause more power loss than gains. Porting is an art and experience is worth a ton. Its not about hogging out the ports but reshaping the port for maximum velocity. This is one reason you can pay hundreds for a nice porting relative to the style of riding. Be carefull if you're going to attempt it yourself and do your research - call some experienced machinists who specialize in porting atv heads and have them guide you.

[monkeyballs]

I understand that it is an art. Im 17 years old and my minde is fixed on becoming a decent mechanic (preformance I hope :D).. Im not going to go and hire some one 2 do this port job since I want to learn. In your own words "...art and experience is worth a ton.." Im sure that they did not learn by hiring other ppl.. Some day I would not minde becoming that verry person that you pay so verry much.. :P

Knowing that it is such an art.. I am doing my research. Wich is exactly what am I doing this very instant.. I have talked to a couple ppl, but they specialize with 2 stroke porting (both case and..).

I understand that you are trying to help me and stop me from doing any harm, and I thank you for that, but the only way I will be happy is if I learn something.. And "experience is worth a ton" so...

Once again thank you for your concern. I will for sure call up a couple mechanics and see what information I can squeez out of them and perhaps they could even help me :D. Finally, I hope you understand where I am comming from and I hope you have not taken any offence from this. Have a nice day.

Bracer Buechli

[ds268]

Ok, ok. You have the same drive I did when I was 17! You're absolutely right that the only way you learn is by doing it yourself and learning from others. I enjoy someone who has determination to do a great job and wanting to lean. I have seen way to many ruined wheelers because they thought they knew what they were doing but hey, I can admit to screwing up as well but you only learn one way! In your case I think you can attempt porting this yourself and I would love to help ya out. Aluminum has a bad tendency to gall or clog the porting bit. If you plan on using a dremel then you're gonna need a few rough sanding bits to get it done. Use slow speed so it doesn't go soft and gall the sanding bits.

I ported my 400ex head years ago probably when I was about 19. I used a compressed air rotary tool with a couple different porting bits. I didn't want to change the inner part of the port so I didn't port past the valve guides. I basically cleaned up the port and rid of mold lines and cast slag and matched ported to the intake for a perfect transition and knife edged the port split wall. You also don't want a perfectly polished port on the intake because a rougher surface will amplify the air/fuel mix as it travels the port. Polishing is usually performed on the exhaust ports where optimum flow is needed.

Edit: This made for a nice and very noticeable torque increase in the midrange!

[monkeyballs]

:D I dont know why but, your reply brought the bigest smile to my face. You could almost say that im happy that your happy for seeing the passion that I have. lmao

I cant wait to get this started. Right now I am just getting redy to do all this. I dont feel like having to wait for parts half way through..

Any who, more to the point. When I sand down the intake port does it matter what direction I am sanding in? Like im worried about it being to rough? Also I just got a kawasaki Piece Rotary Tool Set kit. It has multiple sanding bits. I was wondering what bits should be used for what.. I realy want 2 do a good job.

Would you happen to have any pics of befor and after or any thing like that?

Then something that I thought of that was inspired by a golf ball this was, dimples. On a golf ball dimples are used to decreas resistance.. I know this is new and pretty strange but just think about it.. I was wondering if it would be smart to make hundreds of dimples in the intake port or exhaust port (very small ones..). to increas air flow. Im pretty curious to see how this would work out.

Something else I am kinda worried about, is crank bearings. This is a 2002 and I have put a good amout of km's on it. I was wondering if I should change em. I rather not since its somewhat of a big job and im missing some good riding time. Then again, I dont want 2 blow it up. Im wondering if it is needed since I am droping all these mods in it and it might offset.. (crank bearing pattern). Also what are adequate ways in telling if they are still good?

Well thank you. I cant wait! :D

Bracer Buechli

[ds268]

It doesn't really matter about the sanding pattern as the overall texture. You want a texture between the stock casting and say a brushed aluminum. As far as your golf ball theory, the dimples actually create air drag but their purpose is to produce a slight air pressure difference as the ball leaves the club face, back spinning at a high rate. These pressure differences make the ball climb if hit properly (backspin). Obviously if you hit the ball and give it a horizontal spin it will result in a slice or hook (too much beer ;)). They only serve a purpose in making the ball climb and giving a steeper decent, which increases trajectory, looking like it has less air resistance. It's all physics boy! I don't have any pictures of my port but I can snap some when I swap another carb probably this week sometime and I will post em up.