my moped experment part one -show&tell-video

stay tuned for part2

my moped experment part one -show&tell-video

How did the bike run before you did the porting?

Re: my moped experment part one -show&tell-vid

it was always ported since day one i just opend up the 2 main ports for the intake and ex. a tiny bit but with the V1 motor and this 90cc kit it just never ran with a pipe wtf idk

abd what really dont make sence as i made a homemade stright pipe it was perfectly stight and it wouldint run with that on it ether took it off and sure enough ran good

maybe the exsulst port is to big for the pipe?

Re: my moped experment part one -show&tell-vid


Re: my moped experment part one -show&tell-vid

I'm not an expert by any means, but my crackpot theory is that the aggressive porting is making it not want to run once it falls out of the powerband. The straight pipe can't provide significantly more backpressure than no pipe at all, so it doesn't make sense that it just wants extremely low backpressure. A straight pipe would change the powerband though. The shop vac could be simulating the "sucking" part of the expansion chamber effect, essentially giving you a powerband that starts at 0 rpm.

Like I said, I'm no 2 stroke expert and am probably wrong about this. Just throwing it out there.

Re: my moped experment part one -show&tell-vid

piston upside down?

Re: my moped experment part one -show&tell-vid

Perhaps your seals are blown from the use of the nitrous?

Re: my moped experment part one -show&tell-vid

have you ever just tried pedaling properly?

all you're doing with that vacuum is pulling the charge through to the cylinder better so its obviously gonna start easier

try pedaling quicker so that the engine actually gets a chance to pull the charge through by itself, when you just kick it like that maybe the engine isnt getting enough revs to create the suction to pull air through the carb properly

Re: my moped experment part one -show&tell-vid

never used nos on this motor used it on that kit before tho

Re: my moped experment part one -show&tell-vid

yes i tryed peddlein my ass of as weel as runnin with it can get it to even puff

Re: my moped experment part one -show&tell-vid

My guesses:

Weird port overlap?

Idle circuit in the carb messed up?

Rings stuck in the lands?

You're gonna need a very long extension cord

Re: my moped experment part one -show&tell-vid

Post a picture of the inside of your cylinder? Rig it stock and make incremental tuning changes until you fail and then resolve that issue? That you came up with hooking a vac to the exhaust as a solution suggests you are on the wrong track

Re: my moped experment part one -show&tell-vid

Is your timing set for "juice" and not for normal.

This jacobs ignition had a device for when you hit the button it changed the timing for nitrous, when off, it went back.

Or some ram air, or some porting lessons.

Or an atenna and drive near the trolleys when you need the electricity , get it there.

Shop vac shows the problem, not a solution.

Waiting for part 2.

Re: my moped experment part one -show&tell-vid

Put the shop-vac down.

Re: my moped experment part one -show&tell-vid

look for mopagen on here ask him

I have the 51mm on my minarelli.. but the base gaskets need to be built up on them.. also you should be running the square head.


Re: my moped experment part one -show&tell-vid

I also forgot to mention I have the full circle stroker crank in mine

Re: my moped experment part one -show&tell-vid

Only thing I can come up with is that it's a piston with an intake window near the top, and it's pointing at the exhaust. Pop the cylinder off, and show how your kit and piston are mounted.

Re: my moped experment part one -show&tell-vid

ok will do

hye almost got runnin spryed some premix in the carba dn pushed down the life like my life depended on it and it started puffin and even ran for about 10 secs and pulled me under it own power at about 5mph

when it did run for thoes 10 sec it sounded real week like it was running bun only like half runnin if that makes any sence

i think if I had some nos and give it a lil shot it may be able to really stat runnin and take off

one other thing could get it this lil bit action with the filter off filter on and nothin

Re: my moped experment part one -show&tell-vid

Don't ever hit juice on low rpm's.

Some kid way back in '94 had a 340 with a six pack and NOS, did a power-brake while he hit the button and blew his driveshaft clean off in the school parking-lot.

Re: my moped experment part one -show&tell-vid

Hmm port map the cylinder for everyone to see.

How many base gaskets you have under it?

You know the heads gaskets last like 100 miles on a 51mm..

What range of plug are you running. What is the jetting on the 51mm.. It is bridged exhaust port?

You ... read the .. manual by bell? On how to port a cylinder?

Let me say throw the fucking nitro away.. Piston and cylinder is not meant for this.. its a moped no a bike. My 2 cent.

Re: my moped experment part one -show&tell-vid

im gonna say your timing is way the fuck off?

Re: my moped experment part one -show&tell-vid

perhaps you need a different exhaust to handle the larger carb and cylinder you added... different exhausts are better for different setups... but hey i'm still a novice when it comes to this stuff...

Re: my moped experment part one -show&tell-vid

using 4 base gasket

using a L86c

in the 21mm phbg carb im runnin a 112 main jet and a 60 idal

not sure what u mean by It is bridged exhaust port???

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