View Full Version : stupid scooter drag rules

tiba karotsu
02-05-2003, 10:40 AM
they won't let any modular head cilinder equipped scooter to participate in the 70cc & 90cc class, the only class we're allowed is on the OPEN class category meaning my 70cc is going up against monster 125 to 180+cc drag scooters.

the organizers who made this regulation don't know jack sh!t about scooter tuning and the irony is they sell scooters for a living.

i'm so pissed off by the stupidity of the race organizers and that makes me so mad:mad: i wanna get an assault rifle and pump their heads full of lead.

if they use their brain some of the time they could've figured out it's still a 70cc, local perception is that the reason modular head cilinders are powerful is b'coz of the heads and that is farther from the truth as every self respecting scooter tuning enthusiast knows the modular head's high HP output is achieved by a superior exhaust & transfer port design & not from the cilinder head.

we're now in the 21st century but these guys think like neanderthals " Booga: look this scooter has modular head him not allowed on 70 & 90cc class right?" "Dooga: yes you right modular head very powerful so him only allowed on OPEN class!":lol: :rollin:

02-05-2003, 01:35 PM
Hey Tiba, if you got a spare head laying around send it to the rules committee so they can see that there's nothing to it. Other than shaving it down for more comp theres not a much that can be done. (maybe try to dual-plug it?) My impression with the ``average'' scooter sales shop is that technical knowlege is somewhat lacking. You obviously have the technical expertise to win any argument they have, go for it.

Error No usernames avail
02-05-2003, 03:37 PM
Why do they call them "modular head cylinders" anyway? Are they easily removable or something?

02-06-2003, 01:46 AM
i think they want to stop kits with 2 exhaust ports since all modular heads kits come with 2 ports if so get a jog 90 by all means !

all of your pulies parts fit (plus i have special gears machined for 90 which i can donate) reeds carbs ignation frame etc all bolt on --so real easy to set up and cost less to built than a 70 because you use stock crank and cylinder-- i wish i stil had my 90 --i had countless hours spent and it was fast --it would pull power wheelies with +%20 gearing and stock pullies !

tiba karotsu
02-06-2003, 09:18 AM

KOSO has 47.6mm cast iron AC race cilinder kit and it has 2 ports also. it comes with single ring piston in 10mm gudgeon pin which is useless for a road racing scooter.

with my old MHR LC cilinder & the EVO pipe it would power wheelie using a 40% gear up kit with MHR overrange kit of course, i think the EVO pipe will serve you well for the moment until the custom pipe made by Mr. MBX for our scooters is done.

my old MHR cilinder (both LC & AC) were of the 2 port design, the reason for banning the modular head for competing in the 70 & 90cc class is the power output made by the superior port design, i suppose they want to keep scooter racing in the stone age so that they won't look like idiots when their scooters can't measure up to todays standards.

if ever worse comes to worse i'll be forced to run it in the OPEN class category so i'll put everything i know into squeezing every last ounce of power & rpm out of this engine combo.

it's going to be a very long week ahead of me so if i'm not posting here in the next few days that means i'm back home in the province builiding & testing the scooter.

C U L8R when i'm done.|I

micah apriliaforum com
02-06-2003, 10:13 AM
Do you want me to send you an assualt rifle with those jets? I have an AR15 ready to ship....just joking. Email me today with your address information.

Dutch Royal T
02-06-2003, 05:34 PM
Wow Tiba, that sucks. Finally you was getting ready to take a 1st place after all those first loser places :lol: .

No really, too bad. Start your own league!

02-06-2003, 06:27 PM
well you can port AC to MHR Speed specs and it will perform the same

koso kit is interesting , can drill piston to 12mm from one end and plug it with teflon tubing on other end

Dutch Royal T
02-06-2003, 08:46 PM
Why not get a 12mm piston right away?

tiba karotsu
02-07-2003, 09:16 AM

even if i bring the whole kit to show them that there's nothing to it that can increase power (the heads) their feeble minds wouldn't comprehend nor understand the point i'm talking about but i'll try to convince them one way or another for my sake.:mad:


they're called "modular head" b'coz of it's design, the cilinder head has 2 parts the INNER head & the OUTER head as we refer to it.

the INNER head has the combustion chamber & the spark plug thread machined into it and covers the piston & the cilinder bore.

the OUTER head is then installed over the INNER HEAD which when filled with coolant it completely submerges the INNER head providing better cooling efficency than the old 1-piece head design as found on most road cilinder kits and also on some race cilinder kits.

hope that answers your question.

IP & Dutch,

i think there could be a 12mm pin KOSO piston kit but the Malossi or Polini piston kit will also fit but the cost of those pistons will be the same as getting a new KOSO race 70cc AC cilinder kit.:lol:

02-08-2003, 12:36 AM
Tiba obviously oranagizers trying to controll the costs because slower guys complain that you run special parts which they cant afford , so show them an AC MHR can be ported to Speed specs so they are equall for drag racing as far as water cooling one can just throw a wet towel on a AC ----

i need to make correction : drill 12mm from one end and plug same side (just one plus on one side)--the other end not drilled through so no need to plug

Dutch Royal T
02-08-2003, 10:07 AM
Hey they is a nice idea if I get it right.

Put a 12mm pin into a 10mm piston, of xourse you need drilling, but you only drill one side + the inner side of the other side (still with me? :) ) The you indeed just need one circlip.

tiba karotsu
02-09-2003, 06:32 AM

yup that's what he said.