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Discussion Starter · #1 · (Edited)
We spend alot of time explaining to most that the bike they bought is not 47-49cc and goes 40 plus mph stock.....

Most of the China made bikes have 39.6cc engines. There are a very small percentage that have come over with the big bore head-piston already installed which puts them at..(NO not 47 or 49cc) but at 44cc's measured. I have also seen other "cc" numbers posted for the big bore kit. The main fact is that these bikes are NOT 47cc and 49cc's.

Both the 39cc and 44cc half and full fairing bikes will go 28-30mph stock not 40 plus. Although the ones with the big bore kit will accelerate faster.

I see that there are some new start up companies that are using the 47cc or 49cc numbers to lure customers. I just hope that somewhere in there websites they tell the real specifications of these bikes.

The new water and air cooled B1 replica's are still under 40cc's.

please spread the word to help counter all the innacurate information accross the net.

There are also 2 main pocket bike racing categories... world wide..
under 40cc and under 50cc. Typically anything over 40cc is running in the open class.
 

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i thought the big bores were 48cc?? i dont have one or i would measure myself. but i guess the only way to tell what you have is to measure it. i hear 38, 39, 40, 44, 47, 48, 49...on and on. and everyone says they measured it so someone has to be wrong about the big bore cc's.
 

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Manfactures usually just put these parts togelther its hard to tell what you get sometimes. If your unlucky you get a bad motor. Its dude to poor quality control. With 49cc midbikes I foudn that some 43cc bikes were slipped in. Tagged as 49cc some are 43cc motors.
 

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I really would like to confirm if 39.6cc is the correct displacement. This is the first I've heard of 44cc though. I know for a fact that the non-big bore engines have a bore size of 40.0mm. The Big Bores are 44.0mm. As for the stroke, I haven't confirmed for myself but 32mm is what someone posted. Can anyone comfirm for a fact that 32.0mm is indeed the correct length for stroke? I really need to find the time and just check for myself.

Assuming 32mm is the correct for stroke, with the bore size of 40mm, this would equal out to 40.2cc and not 39.6cc but again I need to confirm the stroke measurement. I'm assuming whoever said 32mm was just rounding it off. For the big bores if assuming 32mm is correct for stroke would equal out to 48.7cc.

If 39.6cc is indeed the actual displacement, then stroke would be 31.3mm (which doesn't explain rounding off to 32mm). Using 31.3mm stroke to calculate the displacement for the big bores, this will give you 47.6cc. I don't see where 44cc came from?

Correct measurement for stroke anyone? Thanks
 

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The so-called 47cc that we have in our shop has a measured bore of 40mm and a stroke of 32mm. That puts the engine size at 40.2cc. If you use the 44mm big bore kit, then you would be at 48.7cc.


I guess the Chinese either suck at math, converting to English, or both. Plus, most pocketbike dealers don't even know what they are selling how how to tell. So, it becomes a numbers game, since everyone thinks bigger is better. So tell me again how the "47's" are faster than the "49's"?!

Here's an easy formula:
Bore x Bore x Stroke x .7854 = cc
Make sure to enter the bore and stoke in cm not mm(move the decimal 1 place to the left).
 

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It's a marketing gimmick. The bigger the better, esp in the good ole US of A.

I bought my FF because it's fun. Not because it has a bigger displacement. I don't think I'll even need to upgrade to a big bore/stroker kit. How fast do you really go in a parking lot anyways? :p
 

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Finest said:
It's a marketing gimmick. The bigger the better, esp in the good ole US of A.

I bought my FF because it's fun. Not because it has a bigger displacement. I don't think I'll even need to upgrade to a big bore/stroker kit. How fast do you really go in a parking lot anyways? :p

i have a 47 cc and 2 49 cc midbikes stock the 47cc blows them away but i have a mid bike modded with exh,rocket key,carb and air filter and it barelly keeps up.
 

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So how do we know what size engine we have without taking th engine apart and measuring the bore and stroke?

How come it also says 49cc in the manual? Can they do that, write false specification in the manual?
 
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Twitch said:
So how do we know what size engine we have without taking th engine apart and measuring the bore and stroke?
You can't.

How come it also says 49cc in the manual? Can they do that, write false specification in the manual?
Of course they can. Who is going to go to China and stop them?

The manufacturers, importers, distributors and dealers who post these false claims of CC's, HP and Top Speed KNOW that 90% of the population is either going to be too lazy or in too much of a hurry to research for the correct information.

I'm not saying the Cagllaris are not a welcome addition to the pocketbike community because they are. But it just goes to show that most Americans are easily fooled into buying something just because someone says it's BIGGER.
 

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Webmaster said:
You can't.

Of course they can. Who is going to go to China and stop them?

The manufacturers, importers, distributors and dealers who post these false claims of CC's, HP and Top Speed KNOW that 90% of the population is either going to be too lazy or in too much of a hurry to research for the correct information.

I'm not saying the Cagllaris are not a welcome addition to the pocketbike community because they are. But it just goes to show that most Americans are easily fooled into buying something just because someone says it's BIGGER.
Well Robert we finally agree on something.
People were so willing to believe the ads that nobody took it to heart
when several knowledgable people posted their findings. This information
about the chinese bikes not being 47 or 49cc has been around since the
beginning.
I would take to heart what ADA said. They manufacture parts for a lot of
motors from 22cc on up, so it is important that they know what size motor
they're dealing with.

The chinese bikes are what they are, inexpensive bikes that allowed the
masses to get involved.

End of Story.

Scott
 

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Ok, mabey this can shed some light on the situation.
I bought my cag full fairing bike and it didn't run very well, so I took it apart found the cyl had a nick in it, no big deal, but I went and raised cain with the place I bought it from.
The guy gave me a new cyl and I went home happy.Only to find the cyl he gave was smaller than the origional.(nobody knows what they are selling,really)So back I went, he couldn't find me a good "big" cyl, so he have me the whole rest of motor(sweet).Put the smaller motor together and it runs awsome.
Now for the clarification.
Big piston is 43.77mm as you can see in the pic, but from the exact same bike the new piston is only 39mm.
So whoever wants to do the math, these mptprs are not the same, and it's hard to tell who has what..

enjoy
Jethro
 

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pintsizemoto said:
does anyone have information on the bore and strokes of the different size engines?

i am wondering - rather than measure both, is there a sure fire way to measure your bore and base that off of someone elses findings?

perhaps all with 44mm bore have Xmm in stroke? etc.?
I have measured the bores for myself and I posted my findings earlier in this thread. The only thing I was not 100% sure of was the stroke since I did not measure for myself at the time which is why I did not say I was 100% sure on it. Well ADA verified what the stroke was in the post right after mine and our numbers agree.

Recap:

Standard bore engine: 40.2cc (40mm bore, 32mm stroke)
With "big bore" barrel: 48.7cc (44mm bore, 32mm stroke)
Standard bore with FCSC: 44.0cc (40mm bore, 35mm stroke)
"Big Bore" with FCSC: 53.2cc (44mm bore, 35mm stroke)



jethro said:
Ok, mabey this can shed some light on the situation.
I bought my cag full fairing bike and it didn't run very well, so I took it apart found the cyl had a nick in it, no big deal, but I went and raised cain with the place I bought it from.
The guy gave me a new cyl and I went home happy.Only to find the cyl he gave was smaller than the origional.(nobody knows what they are selling,really)So back I went, he couldn't find me a good "big" cyl, so he have me the whole rest of motor(sweet).Put the smaller motor together and it runs awsome.
Now for the clarification.
Big piston is 43.77mm as you can see in the pic, but from the exact same bike the new piston is only 39mm.
So whoever wants to do the math, these mptprs are not the same, and it's hard to tell who has what..

enjoy
Jethro
Those measurements may be correct but will not help in calculating engine displacement. When calulating the displacement of an engine you measure the size of the bore and not the piston. The numbers I posted above and earlier are correct.

ADA posted earlier an easy formula on how to calculate displacement:
bore x bore x stroke x .7854 = cc

The formula I was taught in school and use is:
(bore/2 )² x 3.1416 x stroke x number of cylinders = cc or cui (depending if using metric or standard measurements)
 
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