"Mototune" porting: anyone try it?

[VTRDark]

Argh Mototune I went through this site about a year ago. Terrible web design but hey ho the info is very interesting.

Did you find this link on the site.
http://mototuneusa.com/thanx.htm

and then this one
http://mototuneusa.com/power_news_--_homework.htm

I'm not sure about using epoxy (JB Weld) I don't like the sound of that. Would it really withstand the temperatures and test of time I think weld or pouring in some molten metal or something would be better. Interesting site though if one can cope with reading through it all. Love the super glue trick.

That would be due to the gas laws. http://en.wikipedia.org/wiki/Gas_laws

Thanks for posting that Mike, it reminds me of my Scuba diving days.

This causes the outside pressure to push harder and harder on the plunger.

A bit like pressure in the ear canal as one dives (or drop to the deep end in the swimming pool ) without equalising to ambient (outside) pressure.

Back to the cylinder heads I would like to have a go at what they say on the site with some spare heads but without a flow bench I think it would be hard going. Either pot luck or a lot of trial and error and dyno time.

(:-})

[rollingthunderx2]

There's nothing new in this, decreasing the throat of the inlet gives better midrange, but most sports bikes are made for ultimate hp bragging in magazines, so have big valves and carbs for high rev power.

This was covered in Irving's "tuning for speed"..written 60 years ago. A good newish book is Robinsons engine tuning
https://www.google.co.uk/#q=john+robins ... tuning+pdf

Ducati were one of the only manufactures who stuck with high velocity narrow extreme downdraught inlet tracts.

[CruxGNZ]

Love the super glue trick

Be carefull not to glue your skin together before cleaning the wound. You don't want an infection. Also, the US military used superglue to close wounds during the Vietnam War, so it's nothing new. I've used the super glue method several times, but only if the duct tape wasn't around. It works well.
Sorry, a little off topic. Now, back to our regularly scheduled program...

[VTRDark]

Found the following article which supports the technique of making ports smaller to increase flow. Interesting read.

http://cycledoctor.com/the-johnson-syst ... from-less/

(:-})