88cc head porting part deux

So to start with this head is off a 107cc, it has a large angled squish band and more meat and length to the inlet, it also uses the longer cam here:


pic of the stock intake, horrible casting, spring seat protrudes really far into the throat. pretty much the same as a stock honda 90 head.

Valve seats first, much sand paper and course lapping compound. crap job, so i went back to taking lumps out of the intake.

raised the port roof, smoothed down the spring seat hump

i say smoothed…

back to vavles seats

after many many little bits of sandpaper and some help from a drill to spin the valve, the seats are good enough.

Porting is complete, spent more time opening the valve seat throats, they did not match the head very well at all, also widened the port where the stem sits, i could do better but i do i need to spend that much time and foul-stroke?

24mm carb fitted, note how close the bowl is to the head, i think it would not fit a stock 90 head, but it fits this one so i’m all ready!

Race bike needs both brakes, i don’t have a two foot long foot so to match my rear sets i gotta make a brake pedal. and i don’t have a lotta spare metal lying around so the original super tucked in pedal will have to be sacrificed.

scraps of metal found and half the day spent poking at stuff

original pin chopped down and welded to frame as pivot.

Discovers my nice inverter arc welder is actually a piece of shit. i thought it was damp rods, but no, it’s just shit. super cheap tiny AC buzz box welder worked flawlessly.

Nope! pushing the rod is not going to work, feck. problem for the next day.

you know them niggly problems that take years off your life? this wasn’t one thank feck it, converted the throttle cable from a tiny nib thats supposed to act on the carb slide, to a…

..Large round nipple, yeah suck it SEO.


things to do before race day on the 23rd:

lots, not gonna lie and attempt to make a list, i just have lots to do and tools to buy.

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