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Back at the Dyno getting real data and running scary RPM’s

By Rafter


Tony Simoni loves to do Dyno testing. He has been bringing bikes to Carl at Motorcycle Machine Specialties here in Sacramento for about a year now. Carl has a lifetime of tuning knowledge and has been great to work with.

Normally huge motorcycles are propped up on this Dyno getting power readings but on this day 64cc Polini was our subject.

Next years PoliniCup race with have a Polini Puch class. The rules so far include: must be an E50 motor, Polini puch kit, 21 carb, no CDI, any Puch clutch and no case inducting. Sounds challenging.

Tony decided he needed to develop a pipe just for this purpose. So a day at the dyno was in order. We brought with us Tony’s prototype pipe with adjustable header lengths 1 inch 2 inch and 3 inch. Also, everyones favorite pipe the Destroyer, a N8P and even a good ol Techno Boss.

The chart below shows the four pipes best runs.
Green: Destroyer
Red: N8P
Blue: Prototype
Magenta: Boss


The Dyno was collecting data from about 6000 rpm to max.

The Prototype pipe gave us encouraging results for first runs. But it will take some tweaking to be ready for next phase of tests.

Boss pipe did exactly what we always have known it to do. Maxed out at 7.5 HP, hit a wall at 55mph and feels flat across the the whole range. Never hits hard anywhere but for as cheap as it is you do get a good boost.

N8P pipe was true to it’s history as well. Not terrible in the low, hits super hard and pulls crazy beginning at 7HP. Then really enables high RPMs at 9.5 HP. The highest RPM we saw of the day was 11600 on this pipe.

Destroyer was the favorite with best range to top speed comparison. 8.5 max HP during our runs. 10500 RPM at max. Pulls hard right away and only gave up about 2 mph under the N8P.

The Polini Kit we used was completely unmodified out of the box, case matched, HPI ignition, 21 race carb, no air filter, 94 main jet, Malossi 4 pedal reed, Motomatic intake. 11600 RMP outta stock Polini!!!!

Check the Blog tomorrow for results of Tonys bike and road test for top speed.


9 Responses so far

Destroyer in my opinion is the winner!!! On the track it gave me everything I needed to destroy, haha, alan and roundy!!! I can only imagine what the prototype will be like!! and can’t wait to get one!!!!!

where have the rules been posted? No cdi? 21 carb limit? Why?

oh man, no cdi? that’s news to me! hmmmmm

also, do they give out charts that have rpms vs. hp instead of speed vs hp?

i’ve not heard this no cdi rule! that sucks

btw i found your secret hangout, come say hi

datalogs of exhuast gas temperature?

no jetting changes between pipes?

how about timing changes?

what octane fuel and what oil and ratio were you running?

looks like i need to take mine to the dyno.

Do Proma Circuit! Solve the mystery!


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