my bike ... the lethal threat

rogergendron1 said:

ha ha ha yup ... verry fine small drum and fine stone bits took about 4 hours of carefull dremaling !!!! taking tiny amouts off and looking at it and imagining the combution happen and then grinding a lil more ... then i dremmaled it smooth with scotch brite wheels of various grades...

this is all after hours of hand sanding on glass with sand paper taped to it... it took so long to sand of that mile thick gasket surface off, my shoulder and elbow joint still hurt today !!! lol

reshaping the chamber is easy by hand its just time consuming and you need an imagination of how the fuel explodes... imagine it exploding at the plug and expanding out and eliminate all the obstructions in the way , or at least smooth them out enough to effect the speed and path of the explosion.

for instance the sock chamber had a small dome at the plug and a big dome at the chamber and a tinnnny lil squish at the end all with sharp edges ... now when the plug fired the explosion happened rapidly in the lil plug chamber then has to expand by a sharp corner into a larger chamber where it slowes down and loses energy , like water going from a small tube quicky into a larger tube and slowing down then it hits the squish band witch might as well not even exist its so small , and finnishes burning .

in my mind the head would benift greatly if the explosion were to happen in a single smaller high comp dome and fire out in all direction as fast as possable forcing the piston down with the full energy of the burn all at once.

squish bands have there place and they are proven effective this one on the stock head however is a shame full excuse and poor engineering. i personaly think they just slapped it on there to say it was there and make the NEW head sound better lol

a real squish should cover around 30% of the chamber and be used on high comp higher rpm motors where that secondary burn can be noticed at higher rpms

for instance the puch head i installed ... its about the same comp as the old head but the squish was designed for torque so my bike has a much snappyer midrange now than before
with the hemi type dome it was just broad power all over and some extra emphasis on the top end

well i guess you could say there is a squish band .... it has a 0 degree horizontal squish typicaly assotiated with 4 strokes, now that the chamber has shrunk. its about 10mm wide and is the flat surface that has been sanded off by decking down the head. but it is a verry close squish and fires what little it traps horizontaly into the chamber to make tubulance in the explosion , but its not a typical up swept angle 2 stroke squish.



read...........

http://gasgasrider.org/html/measuring_squish.html

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rogergendron1 said:

i know that plug is longer ..... i would check and do a test fit with the motor at top dead center and see if it hits, or hits wile easily turning it over by hand .
try a champion L86C a nice short plug or a nkg b6hs

i was scared to run that plug with my old angle head but i am looking to buy one now that the puch head i have has more clearance de to the top plug design.

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rogergendron1 said:

A lil les comp and a way better fuel burn would be ideal for a longer running more reliable motor . i would have done the same had i thought of it lol

but i can run it now with the puch 70 hi hi so all is well

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rogergendron1 said:

your right ... the protrusion of the electrode would reach in enough to displace at least a half a cc more than a standard.

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