Most important mods...

Good nuts and bolts along with different, better mounting studs for the head and mounts. port matching the exhaust. Dont worry too much about the intake unless thier is a lot in the way. a better clutch arm.I made one with a few tools I had around. http://motorbicycling.com/f13/custom-clutch-bar-piston-skirt-trimming-8609.html
After that stuff you have the main stuff in your paragraph you can trim the piston skirt, expansion chamber, different intake.

add a double nut to all bolts.
i would add a metal strap from exaust bolt to top bike frame and a muffler strap.
i added a forced air intake pipe on mine,its a rubber boot from a bike shock hooked on the end of the carb then its turned forward along side of engine and connected(taped)to a 6" aluminum pipe tied to clutch cable. you can add a filter to the end but i didnt yet.
it runs alot faster than a stock airfilter plastic thingy.
plus i use a o-ring in the carb to intake,stops airleaks.

Cabin fever do you have pics of your mods Thanks

Instead of an expansion chamber you could start by making an exhaust pipe with the proper dimensions of it. I did some mic'ing and a pipe with the inner dimension of 21mm should do, and if you make it 20" long then put your standard muffler on it you will get a boost in performance. Make the bends in it look cool too. Thats what i'm going to do then I will by an expansion pipe down the road when I want to splurge on the money. You would have to make your own bracket because the stock bracket for the muffler pipe the Inner dimension is too small, if you can do a little metal fab.

here you go beetle some pics of my mods.

Good stuff guys thanks for all the help I will send pics of mine when I get it finished Beetle Juice

I think another great modification would be to add an electric start, ive been thinking about rigging something up for a while know, i have a 7.2v ni-mh battery 2400mah and r/c car motor with lots of torque enough to turn the engine, i would charge the battery off the magneto, my problem is finding a way to mount the r/c motor so it would disengage from the pinion on the motor once its started because if it spun with the engine it would eventually burn out, if you have any idea get back to me.

Cabinfever- That’s an interesting idea, haven’t seen that before. Certainly looks good. That might be a good way to solve an upgraded air filter space problem. Have you run it with and without the forced air pipe? Could the better performance be mainly from the lack of an air filter? I wonder if the pipe had a slight taper if it would have an increase Venturi effect?

1st pic is MOOP2 upside down full tank not leaking any fuel.
Work on your bike remove wheel and fix a flat do anything practically on the side of the road like any regular bicycle.
Gas tank mod used a filler cap made for a boat picked up at a marine shop.
Used epoxy clay to seal the tank. Also have a spare cap with two small holes drilled
in it for when I ride so my tank can breathe. When it sits I replace the solid leakproof cap.
Someone steals your bike with that solid cap on it will quit on them after about a quarter of a mile. Chances are if witnesses see him he may just dump the bike so it's an anti theft device too.
Even in the float bowl it doesn't leak I think it's because of the vacume this creates in the tank.
And when you store your bike,the gas does not evaporate or disapear.
You can almost store this indoors yo.

2nd pic is my frame mount rethink on MOOP2. Since my frame is skinny enough for the stock mount to grab the frame the stock front mount is grabbing that frame and on the rear I added another rear
mount. It hasn't loosened up or anything. This is idea for the old style frames where the mount
will hold tight. You can substitute that second mount for anything with two holes drilled to it even
a piece of hardwood I would imagine.

3rd pic is an old pic of MOOP1 before this forum was even born. You see my clutch mod but also
check out how I used my derailier cable stay as my clutch cable stay. I redid this to MOOP2 later on
with a frame clamp. Clutch pull is effortless.

4th pic is a choke mount on the handlebar. I used a front derailier clamp for this. With some thinking
anything is possible.
I didn't transfer this to MOOP2. Instead on MOOP2 I moved my throttle to my left and my clutch
lever to my right. That way I can fiddle with the choke with my right hand while my left hand is doing the throttle.
And when you are adjusting your idle when you are stopped clutch is on your right hand left hand is adjusting your idle screw.
It makes things alot easier for me. Also it feels vintage because early Indians have their
throttle on the left as well.
Try it. It may blow your mind so you have been warned.
Throttle will turn the wrong way but I think it gives my bike a certain character.

And this is just the china 2 stroke. Other stuff included my Boost Bottle it's a debate on this but
it makes my engine run really smooth.
Also switching over to metal core spark plug wire.
And zero ringing your carb for a tight fit no air leaks.
Muffler mod too....
I'm missing something....

i ran it with stock filter and plastic cover = 28mph w/fast acceleration-could be better
i ran it with no filter and pipe pointed toward the rear=30-31mph takes off like a rocket
i ran it with no filter and pipe pointed toward the front=30-35mph takes off like a rocket and then once it reaches over 30mph, i here a air noise in the pipe for a second then the bike really takes off.

i will be adding a thin air filter midway between hose and pipe,but nothing to thick as i dont want to loose any speed or power.

i think a spiral shaped pipe would make sort of a tornado effect and help with the mix of gas-oil and air.

Cabinfever- Wow. Thanks for the detailed results. Yet another thing to add to my "to do" list. Please post the pictures of the type of filter that you end up using.

brandongordon2002 said:

I think another great modification would be to add an electric start, ive been thinking about rigging something up for a while know, i have a 7.2v ni-mh battery 2400mah and r/c car motor with lots of torque enough to turn the engine, i would charge the battery off the magneto, my problem is finding a way to mount the r/c motor so it would disengage from the pinion on the motor once its started because if it spun with the engine it would eventually burn out, if you have any idea get back to me.

Click to expand...

some lever so you could engage it then take it off or some type of centrifugal clutch thing maybe just an idea