Motor Scooter Discussion Thread

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kizza1645

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Motor Scooter Discussion/Pictures Thread

Thought a few of you might own one of these babies.

This one is completely custom, and made in the USA. I put it together here.

Used to ride to work, hit 75kph.

Goes fine on the jumps and dirt, very reliable engine.

Constructed mostly from ddm racing parts

Specs:
47cc USA made engine (pings like a good 2 stroke)
SikM1 pipe
Fusion Deck
K&N High flow chromed race filter
Allow Cooling head
Nitrous Oxide injection
Boost bottle double rich rejection system ( yes I meant rejection not injection, more explanation if asked)
Racing slick tires
DDM bars
Lizard Grips

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Thing was built like a tank, unbreakable and very fast. Actually probably faster than those ones you see on the street those 49cc ones.

Quite loud as well, hit top 10k rpm id say easy.

Heres a video
YouTube - GSR-40 Fly-By
Video is quite old to be honest, didnt have any moto helmets back then. But safety first.

Heres a video before it was rebuilt completely, still sounds crazy compared to some other scooters.
http://www.youtube.com/watch?v=4_RdGAtNVa0
 
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FOOK! id be ****ting myself on that at 75k's unless i was in full leathers and gear lol,

another thing.. how do ya go with the exhaust there? looks like it would be easy to burn yourself? and looks to blow the exhaust gases right onto the deck?

never the less looks insanely fun, and dangerous... which makes it funner :D
 
FOOK! id be ****ting myself on that at 75k's unless i was in full leathers and gear lol,

another thing.. how do ya go with the exhaust there? looks like it would be easy to burn yourself? and looks to blow the exhaust gases right onto the deck?

never the less looks insanely fun, and dangerous... which makes it funner :D

Its safer riding this then my old atomik which started shaking, passing 80.

The exhaust wasnt a problem for ME, but when doubling people they got burnt.

I have at least 4 permanent scars from exhaust burns, contributed to this very scooter.

Theres nothing you can do, it was the only way to mount the exhaust, and i needed it because it was a tuned pipe. Btw that little exhaust on the end is actually a silencer, and it seperate by some high temp hose, it didnt get as hot as the actual exhaust.

The even funnier thing is, 2 strokes will spit oil from their exhaust, and when I lost my stance on the deck id enter the path of some extremely hot liquid. But who cares its all just a bit of fun. Just man up and your good to ride this death machine.
 
would love to see the nitrous injection up close. how did you plumb it? wet or dry? what solenoid did you use?

kinda makes scooters a bit more cool. wouldnt see justin bieber on that scooter.
 
would love to see the nitrous injection up close. how did you plumb it? wet or dry? what solenoid did you use?

kinda makes scooters a bit more cool. wouldnt see justin bieber on that scooter.

Well they way I had it rigged. Was by using medical grade nitrous oxide through an injector kit from Boost Industries. The kit was a connected to a manifold after the carb, so its wet. Mixes with the fuel and air.

You would almost think your going to flip it when you rip the nitrous.

The second boost industries product was the double rich rejection system. In 2 strokes, upon hitting the powerband, the heat created can cause the carb to run different, providing a double rich fuel mixture, obviously ruining anyway you had it tuned.
So this removes that double rich, by storing excess and not required atmoized fuel in a bottle that looks like a boost bottle. And providing that fuel when needed.

Its a much more technically advanced scooter than you can just buy.

I only have one photo of the setup, and it doesnt include the nitrous bottle, as i was out at the time and this is also prior to head rebuilding.

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This scooter is no toy, and i wouldnt trust justin bieber on this. He's high pitched voice wouldnt be heared over the roar of two stroke awesome anyway.

Ps if anyone is looking for some nitrous oxide pm me, as I have some available to me.
 
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And there is not problems with it. Like your steering?

But orther wise nice work.
 
And there is not problems with it. Like your steering?

But orther wise nice work.

Steer exceeds 100 degrees degrees in any direction, as opposed to our motorbikes.

So steering is perfect
 
thats not a scooter... this is a scooter lol (shty pic but does the job)

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also that boost thingy design has been around for decades... i think it was from 1982 yamaha had a system called roost boost on there yz engines (and possibly others)

also if your adding nitrous what method are you adding fuel?

if your not adding extra fuel then the nitrous while adding maybe a hint of performance is also killing your engine quicker than running it in a dust storm without and air cleaner

worst thing with 2 strokes is its very hard to hear them ping...

also with nitrous.. then more bottle pressure you have the better the blast..
heat the bottle for more pressure...

i built a mate a nitrous spec roller cam'ed 350 chev a few years back and thru a 250hp nitrous kit on it. (obviously heaps more specs than that but)
off the bottle it ran like mid to high 11 second 1/4 passes.. on the gas at normal bottle pressure it ran close to 11 flat every run...

i knew it had more in it so i put a bottle warmer on it for about an hour.. and bingo 10.34 on the 1/4 and wheel standing... (i think it is in the second edition of the grunt files video if anyone has them.. shtty looking black UC torana)

word of warning tho, dont leave the bottle warmer on for ages lol. we had a nitrous bottle tap blow off a bottle... froze half the boot lol...no danger tho..



anyways, enough talk of nitrous as its illegal to run on the streets. just as i believe these scooters are also illegal to be ridden on the streets..(i could be wrong tho...)
 
these things are mad !. love the idea, gets me keen to go and build one :p. i believe that as long as the engine size is bellow 35cc then you don't need a license or have it registered. Well that the case here in Tasmania anyways.
 
Sean, the effects of the nitrous, with the gasses expanded as you say, will not make much difference in a single cylinder 47cc motor. The jets where always run a little rich to compensate. But the nitrous cancels out most effects from the carb.

Something alot of people dont know is that nitrous will retain heat inside its molecular structure, thus reducing alot of heat. If you ran pure oxygen through your engine it would melt - which is why nitrous is one of the most useful performance gasses available - because of its heat retention.

Depends where you live as well for legalities.

Btw my bottles were compressed beyond their set limits - legal and safety.
So pressure is no problem, holding the solenoid trigger for 5 seconds emptied a bottle.

You must understand, I can go out right now, get my motorbike, hook the nitrous up to my air filter and would go faster than ever before. These little motors dont care much about specifics.

Also why did you mention that double rich rejection has been around for a while? I know that, its tried and tested technology. Theres just companies now which specialise in this.
 
these things are mad !. love the idea, gets me keen to go and build one :p. i believe that as long as the engine size is bellow 35cc then you don't need a license or have it registered. Well that the case here in Tasmania anyways.

Go ahead build one there fun.

ddmracing.com

Going to cost the amount of a 140 but..
 
lol.. your not getting it...

to add nitrous you need to add fuel to get extra power or it will lean the hell out of the engine and melt sht...

i suggest you do some more home work and take a look at proper nitrous systems... they have a fuel solenoid and a nitrous solenoid.. some 2 of each some 2 solenoids for each inlet runner...
in your case the trigger acting as the solenoid...

i know a car setup and your setup is totally different but basic rules still apply...
 
lol.. your not getting it...

to add nitrous you need to add fuel to get extra power or it will lean the hell out of the engine and melt sht...

i suggest you do some more home work and take a look at proper nitrous systems... they have a fuel solenoid and a nitrous solenoid.. some 2 of each some 2 solenoids for each inlet runner...
in your case the trigger acting as the solenoid...

i know a car setup and your setup is totally different but basic rules still apply...

I understand this, but im stuck with my current equipment. And it works.
Why bother changing or messing with it? nothing has gone wrong for years and its run 100s of grams of compressed nitrous through it.
 
id just build one from scratch. chop up a 12inch bike frame. and whack a chainsaw engine or something on it. deffently a custom exhaust to quiet it down some what tho. when running nitrous, its gonna make the engine rev faster yeah ? , so its gonna need more petrol in theory but the nitrous also burns and since it such a small engine it wouldnt matter too much would it ? have you thought of running it on methenol ? im not sure if you can though because its a 2-banger?.
 
id just build one from scratch. chop up a 12inch bike frame. and whack a chainsaw engine or something on it. deffently a custom exhaust to quiet it down some what tho. when running nitrous, its gonna make the engine rev faster yeah ? , so its gonna need more petrol in theory but the nitrous also burns and since it such a small engine it wouldnt matter too much would it ? have you thought of running it on methenol ? im not sure if you can though because its a 2-banger?.

ahahah 2-banger.

Na you should mess around with fuel sources. Btw a wipper snipper wont have the power even if its a 47cc. Their engines just arnt designed like that. Ive seen it done, but there slow. You can import one of these us engines for under $250.
 
Fair point. But what about a chain saw ? they sound like they got plenty of power or are they just all bark and no bite ? i cant really import i dont have the funds i cant work atm cos im having chemo therapy and that knocks me around .
 
Fair point. But what about a chain saw ? they sound like they got plenty of power or are they just all bark and no bite ? i cant really import i dont have the funds i cant work atm cos im having chemo therapy and that knocks me around .

Well the chain is designed to run really high rpms, but only for a short period. If you can obtain a 2 stroke lawn mower engine, 125cc or similar you can strap that on to anything. Change your carb, you got a machine.

If your short on funds id be happy to help you out, I have boxes of carbs, and some engine parts. If you ever need them.

cheers
 
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