Honda Metro / Crea Scoopy Un-Restriction & Tun

optionboy /

My friend and i just picked up a Metro / Scoopy 2 days ago. i saw it on the web and had to go check it out at the dealer. Not too many people seem to know a while lot about them, so, I am working on fabricating some parts to open it up a bit. I have gotten it up to 40-45 mph with no prob just cruising around, but i really want it to cruise at 50-55, so i am looking for all information to "unrestrict" these things. With a simple pipe / expansion chamber kinda addition, i think it will unleash a few more mph, but i feel a restriction kick in as soon as i hit around 40 mph. i think a simple tuning of the carb and exhaust will help a lot. D&D makes a carbon fiber exhaust that is pretty small, so myself and a couple people from a shop are going to start experimenting. If anyone has already tinkered with the motor a bit and got some more power, please let me know. I am about 160 lbs., and it has no prob getting up to speed. My friend who is abound the 200 range has no prob either on flat land, but it goes a bit slower up the hills. even for me. it is only 50cc ya know. these little scooters are super perfect for cruising around town, or going to college or something. you can't mess with the gas mileage either. i am working on connections as well to the japanese market that has a lot of stuff for em it seems. i am having trouble finding a lot of it online, so PLEASE E-MAIL ME IF YOU HAVE UNRESTRICTED YOUR METRO**. i need to know exactly how. as soon as i find a nice pipe that works for it, i will post and let everyone know how. i run and will be re-launching that site again soon with step by steps on how to make things things kick more butt. I will be painting a few parts as well as tuning it a bit with a local shop. it will have movies and all of the metro which nobody seems to have yet either. i totally love mine so far and recommend it to anyone who needs to have fun or get around town easily or park at school. enough typing* go buy a metro / scoopy and have some fun

Re: Honda Metro / Crea Scoopy Un-Restriction &

What is the "scoopy" part all about?

Re: Honda Metro / Crea Scoopy Un-Restriction &

it goes 40 to 45 stock?????????? or is the speedometer just bouncing around and you call what the most it bounced 2 the fastest you went

Re: Honda Metro / Crea Scoopy Un-Restriction &

InfectedBootSector /


The Crea Scoopy is the Japanese name for the Metropolitan. The were released in Japan in 1999, but didn't meet emmissions here until they did a few little changes.

Anyway... optionboy.

Don't waster your time worrying about how to get the Metro to go faster! You'll kill it!

I know a lot of different foreign performance dealers, and none of them know about anything for the Metro coming at least until December.

Many places here in the states probably won't even sell the stuff because these bikes were built to meet Carb 2004 standards, and it would be illegal to mess with the echaust system in any way other than replacing the stock parts.

Sure, my Puch with it's 70cc kit would beat the Metro, but for reliability sakes, I'm going to leave the Metro alone. It's awesome enough without the performance stuff!

I've never seen a 50cc bike pull hills like this thing does.

No 'expansion chambers for 4 strokes

4 strokes don't function that way

So different exhaust pipes don't have the effect they do on 2 strokes (big effect).

and ... you are also gonna find that 4 stroke mods are a lot more expensive than 2 stroke mods.

(and less effective)

you would need different camshafts and big bore kits and loud exhaust pipes.

And installing them is a LOT more difficult.

Truthfully .. you are better off just living with Hondas excellent engineering .. and enjoying what you've got.

Good acceleration and over 40mph top speed for a 50cc 4 stroke is pretty darn good.

Re: No 'expansion chambers for 4 strokes

InfectedBootSector /

Ah crap.. Haha.. I forgot we were talking about 4 strokes here.

I agree Fred! A good Honda is a Honda left alone!

I've said it about my Mini Trail 50, and my ATC 70, and I'll say it about the Metro I have. They are great just the way they are!

Re: Honda Metro / Crea Scoopy Un-Restriction &

thanks for the quick style reply back, I appreciate it. i totally agree with you that it is really peppy for a 50cc 4-stroke. if it were a 2 stroke an expansion chamber would totally help, but it is a 4-stroke. the stock exhaust on this bike is stupid big. as big as a pepsi 2-liter bottle with a straw size opening at the very end to let the yummy fumes out. i think all the low end torque on these bikes comes from the back pressure created by the exhaust. over in japan where these things are everywhere, u don't really cruise crazy top speeds all over town because there is simply too much traffic and too many lights. it was given a lot of torque because that is what is needed over there to get the hell outta the way when the light turns green, hehe... to clarify my itch for modding this thing, i am just a tuning freak. i can't leave anything stock. lmao. just the way i am. just for fun i am going to experiment with a different exhaust, but i am going to take into account the size of the motor and actual amount of gases flowed when strapping on a different pipe. i need the back pressure, but need a little more free flow for the desired top speed. the bike has a compression ratio of 12:1 so i think that is where the power is coming from in the first place. that is high for a little 4 stroke. 2 strokes are notorious for having high compression ratios. that is where their power comes from. honda did a good job creating this bike in the first place, so i am not going to tear apart the motor and change the mechanics. i am howerver going to see what i can do about the exhaust and taking off what "restrictions" honda did impose. knowing typical honda, it is restricted on the intake and fuel inlet side. there is no huge CPU that is holding back the power, but i do need to check on a speed governor type system that i may think is there... also, on a japanese note, there are a bunch of funky accessories for this bike in japan, i am working on getting a couple, as well as obtaining the little digital info-center addition that the bikes come stock with over there. to all that posted, especially INFECTEDBOOTSCOOTER AND FRED, thank u. u seem super knowledgeable and i am sure we will be swapping info down the road*** seek and destroy - ride safe

thanks for the advice and talk at ya later =D

Re: Honda Metro / Crea Scoopy Un-Restriction &

InfectedBootSector /

I am almost certain there is somthing in the ECU that keeps it from hitting too high of a top speed, because you can feel it let off when you hit 40 mph. Have you noticed this?

Re: Honda Metro / Crea Scoopy Un-Restriction &

optionboy wrote:

> the stock exhaust on

> this bike is stupid big. as big as a pepsi 2-liter bottle

> with a straw size opening at the very end to let the yummy

> fumes out.

Yeah .. they are big .. but you know what ?

- Thats the only way to make HP and be quiet at the same time.

You are mistaken in thinking that big means lower HP .. Big mufflers allow big HP .. while being quiet.

I'll bet you $20 right now that whatever exhaust you put on it makes it go slower .. (or .. at least no faster).. and it will be annoyingly loud.

> clarify my itch for modding this thing, i am just a tuning

> freak. i can't leave anything stock. lmao. just the way i

> am. just for fun i am going to experiment with a different

> exhaust,

Fine .. do a test for 0 to 40 acceleration BEFORE you modify it ... then see what happens after you second-guess the smart engineers and computers Honda used to get the performance they did.

The old days of slapping on a pipe and gaining HP are over .. half the guys who slap pipes on their crotch-rockets go slower too .. they just don't realize it.

> 2 strokes are notorious for having high

> compression ratios. that is where their power comes from.

Not really true at all ... their corected comp ratios are down at 8 to 1 or 9 to in most cases

Re: Honda Metro / Crea Scoopy Un-Restriction &

david f martin /

I looked at a Metro last year, after my QT got stolen, but I don't remember much about it, except that it's 4 stroke.

Does it have a variator trans, or a multi-speed trans? If it's got a variator, that's something you can mod or unrestrict without too much trouble.

Another 4 stroke bike I looked at had a 4 speed auto trans:


BTW, these guys have never returned any of my emails regarding parts or their bikes for sale, so I'm not too sure I can trust them... I'm not crazy about the slow crappy midi that loads up every time, either.


Re: Honda Metro vs. Kymco

I saw a girl riding one today, and I was on lunch break, so I didn't get a chance to race her. I know after my scheduled mods, I'll be cooking up most other "moped class" vehicles for breakfast.

I would like to see how my bike fared against the met, with just my pipe on. I think I would have lost, as it sounds like it has me on takeoff and pulling. Past 40, I know my bike would leave the "scoopy" in the dust..... but before 40, I don't think I'd fare well. 50+ on level ground would be enough to toast s met, but every time we hit a stop, it'd be the other way around.

when I get the 70cc kit ,stiff clutch, carb and torque springs with heavy roller weights....I'll race any 50cc class bike. I think a modded Aprilla would chew up a kymco, modded or not, though. those Aprillas are ver' nice.

the met is a small bike.... I like that....but I also like sitting high up, like on my Kymco super 9....

I think I'd like to see my wife race the met on her people 50.... that thing goes much better than my super 9, at least for now. it has the pulling to keep up w/the met, and it would be a contest to see who could hold the higher part of 45mph....

hehhe... just imagining virtual scooter dragraces---- and drooling over how my bike will soon kick your bikes asses...

heheh piston kits kick ass....!

Re: Honda Metro vs. Kymco

david f martin /

I think they have scooter races regularly in Hawaii... You want a fast scooter, they know how to build them over there. They get speed parts directly from Japan, in blister packs with Japanese labeling... See

There's a drag strip in the town I live in, but I've never been there. Apparently it draws a lot of folks, though I've never been there. They operate on Wednesdays and Saturdays, and anyone can race.

I've never heard of any 50cc racers around here, but it would be fun to round up a couple and go to the races...


Mini's at the strip.

hahaha ... I went to the strip last summer twice .. and both times they had little kids running ... (about 3 of them) .. one had a Briggs and Stratton type minibike .. and the other two had small Jap minis.

It doesn't seem very appropriate .. because they don't have the HP to spin the wheel or anything .. but what the hey? .. they paid their money just like the rest of us.

(takes tham all freakin day to reach the end though!)

I think ther B&S bike was getting 38mph at the end.

Re: Mini's at the strip.

david f martin /

I'd get out there. I love making a fool of myself sometimes... I think it'd be fun to watch, too.

Some of those Hawaiian peds are claiming sub 11 and over 90mph in 1/8. I wonder if they're at all drivable on the street... You'd have to be a maniac!


4 stroke vs. 2 stroke

the mechanics of the two types of engine are totally different. 2 stroke engines fire on every revolution of the engine. 4 strokes, every other revolution.the revolution of the engine that the engine doesn't fire is used to push out exhaust and draw in the fresh air/fuel mixture. the crankshaft is used to 'pump' the air fuel mix into the cylinder on a 2 stroke and the incoming mixture is used to force the exhaust gas out of the cylinder. this is part of the reason that the shape of the pipe is so important on a 2 stroke. like a musical instrument, it is 'tuned' to help optimize air flow. the 'megaphone' cone shape of the exhaust lets the exhaust charge escape easily. the reverse 'megaphone' shape on the other end of the pipe helps to slow down this same charge to keep the fresh air/fuel mix from just following the exhaust out the exhaust port. the more air/fuel mix in the cylinder with the least exhaust in the same cylinder, means more power.

all this is accomplished with camshaft timing, lift, duration, ect... on a 4 stroke engine. fresh air/fuel mix is drawn in thru the intake port, past the intake valve, as the piston reaches the bottom of the cylinder, the intake valve closes, the mixture is compressed. around 10 to 20 degrees before TDC the spark is fired, pushing the piston down. as the momentum of the piston forces it back on the upswing, the exhaust valve opens forcing the exhaust charge out. the size of the exhaust pipe is more important than the shape for a 4 stroke because it doesn't need the shape to help scavenging. port shape is more important. valve size, cam profile (lift, duration, overlap,...), carb size, ect.

tell some guy with a CB750 you can't build a honda. tell the kid in the civic you can't build a honda... I think they'd reply, " you need to quit smokin' that s#!t, it's bad for you.

2 stokes in general make about 50% more power for their displacement, but they don't burn their mix completely (that's part of the reason they smoke, VOLUMETRIC EFFICIENCY) if they did it would be closer to double.

both can be made to make power, just gotta do like the nascar boys. "you can make any engine go as fast as you want to spend your money."

Re: 4 stroke vs. 2 stroke

A CB 750 is ancient history ... In the old days it was easy to hop them up ... it is NOT nearly as easy to hop up any modern Jap 4 stroke bike.

If you think it is .,.. you have no clue what you are talking about.

They are already running stratospheric RPMs

They are already running very aggressive cam lift and timings

They are already running very high comp ratios

They are already running huge carbs or injection bodies.

The stock exhaust flow huge quantities with little restriction.

I'm talking the bike motors (not cars).

The modern engines (like this Metro) .. are already very highly tuned .. and most attempts to speed them up .. make them slower.

... and the costs to hop us 4 strokes us way more expensive and more complicated than 2 strokes.... which I already stated.

Go ahead ... knock yourself out .. its not my money.

.. and we'll see if it gets faster ... or slower .. when you are done messing it up.

Make sure you measure the performance first before mods.

(now .. if they have an RPM limiter you can eliminate .. thats another story)

Re: 4 stroke vs. 2 stroke

Like I said you can make ANY ENGINE FASTER. how much money do you want to spend.

as for honda, they're worried more about RELIABILITY, emissions laws, noise laws, LAWSUITS, WARRANTIES... not saying that their engineers aren't worried about performance. just that it's just a Piece of the puzzle for them.

the basics of making power have been around since the internal combustion engine itself. if you want to make power, just putting a pipe on ain't gonna cut it. Gotta MATCH PARTS. CAM TO INTAKE TO CARB TO PIPE TO BREATHER, ECT...

like you said, check out what you have before you go messing around with.

It's like martial arts, just because you know how to break boards doesn't make you a black belt. it's just PART of the big picture. you have to work on ALL OF THE BIKE to make it faster... and remember that to make it faster, you may be trading off, reliability, takeoff, quietness,idle quality... so is it worth it?

Re: Honda Metro / Crea Scoopy Un-Restriction &

yeah, it is an auto variator trans type... it's pretty smooth actually. does well... no complaints so far

Re: Honda Metro / Crea Scoopy Un-Restriction &

david f martin /

The variator may have a limiter on it that you can remove. Go to, they have an article with pics on how to do it to an Elite. Your variator may have the same type of restrictor on it.

I don't know how much top end that will add, because I had to replace a belt within a week of doing that mod, and I noticed a much bigger difference with the new belt (8-10 mph)... I'd expect around 5 mph better.


hawaiin scoots deluxe

when it comes to mobbing scooters all over town, hawaiin's got it down. they are the middle ground between here and japan, and many locals are japanese that go back and forth all the time, so they get all the deluxe parts and mods. we have a totally different view of scoots over here in the US. over in japan and parts of hawaii, it is the differece between practical and rotting in traffic for hours. so, they turned the whole scooter transpotation gig into a total sub-culture. it is the same way in a lot of parts of korea and all over the world* the U.S. always gets the leftovers when it comes to cool motorized toys. i am actually amazed the metro made it over to the states. i am personally into the 250 and 500cc 2-stroke japanese street/race bikes. evil ass powerband. omg. too much fun. they are super light, sick power to weight ratio, and have a huge cult following in japan that people here have no idea about. they are wayyyyyy hard to find these days, but if u can get one u are stoked. i just rode a friends 250cc 2-stroke yamaha and it bones out! wayyyy to much fun. they are ultra light with huge brakes and are easy to throw around. they were made with the circuit in mind originally, and actually hit our shores for a short time... i am sure there are people on this board that know what i am talking about. i have a big poster of an RGV-500 in my appt that i drool over everyday. someday, oh yes, someday i will have one. mmmmuuahahahhaahaha!

Re: 4 stroke vs. 2 stroke

okay, i might as well draw the line for sanity sake... 2-stroke and 4 stroke engines are completely different worlds. they react differently to mods, have entirely different engineering principles, and are the difference between night and day when it comes to talking about how you want to tune. faust, it totally sounds like you know what you are talking about. i agree with a million things you are saying. my actual background comes from road racing and mountain racing (togue) a honda civic hatchback. when it came time to tune i asked my self a simple question... what will i be using it for? i wanted a shiet load of top end, wanted to compete on a circuit style track, and wanted reliability. i chose the twin cam honda b16a motor. i am not trying to shove honda's principles down peoples throats here, but when it comes to stock engineering for race purposes, honda has been doing it almost longer than everyone when it comes to four cyliners. all the engineering and research they did for their gas saving cars of today all originated from race bikes of the past. honda to date has one of the best flowing head designs on the market. hence the crazy gas mileage and power to displacement ratios. N/A (naturally aspirated) tuning has become a passion for me. i love the principles behind it and believe it is the core of true engineering. FAUST was completely correct when he was stating that if you begin to modify a 2 stroke, or even a 4-stroke motor, you have to be careful. the exhaust size, intake size, internal measurements, and compression ratios are very carefuly matched to provide PEAK hp, and PEAK reliability and mileage. i am not intending to jack with my motor in some dumb effort to make my bike louder and slower. i actually stated that the size of the exhaust MOST LIKELY gave the bike more hp in the first place, as well as torque. like i said, what was the metro originally designed for... tokyo streets... why? so kids can get to school and work... what did they need? a balance between torque and top end out of a 50cc. honda nailed it pretty well when they mixed up the metro / Crea Scoopy. however, honda is NOTORIOUS for restricting their engines as well as exhaust specs. look at the emissions! their are none! lol. of course it is restricted. honda often actually displays the speed and tach accordingly so u think u are going faster than u are, and always sets the red line of their cars and bikes WELL under what the motor can safely go to. so, if the bike says it can go to 14,000 rpm and the rev-limiter kicks in at 11,000 you better believe that the motor can safely be driven up to 13,000 safely. they set it up like that so their are fewer reliability issues and corporate doesn't have to lose money replacing busted warrantied parts. it is all about the bottom dollar. that is why you go by those stupid radar signs (at least here in CA) and it says you are doing 38 and your speedo says you are doing 42. it is all about staying safe, avoiding lawsuits, and providing reliable vehicles. i think with a few SIMPLE mods, i can uncork the metro just a little. all mods will be done and measured AFTER i run base line testing on bikes weight, fuel in tank at testing time, temperature, altitude, rider weight,etc... i am used to fab/tuning principles and know that a simple thing like ambient humidity can add or subtract tons of power... welcome to the world of N/A motor tuning. lmao. like i said. much fun. hehe. long live the scoot*!!!

Re: Honda Metro / Crea Scoopy Un-Restriction &

thanks for the heads up, i will check it out* =D

street drags????

ohhhhhh not good.....just watch a few shows on street racing. bad stuff :(

Re: Honda Metro / Crea Scoopy Un-Restriction &

my metro only hits 33 mph how do i get it up to 40...i wish....tried everything....when i first got the bike it went 23mph...i made a pipe and mest with the carb but only was able to get 1omph more......anyone??????????????

Re: Honda Metro / Crea Scoopy Un-Restriction &

need help only 33mph on my honda.......and im a 160pounder....when i first got the bike it went 23mph...have made a pipe and mest with the carb..... got the extra 10....want the 40 you guys talk about ...just ordered the belt hope i get a little more...but when im at 30 feel that restrictor and then only 3 more

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