Engine sizes

GoldenMotor.com

wheelbender6

Well-Known Member
Sep 4, 2008
4,059
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TX
Good question. I guess we can't tell for sure until somebody uses a micrometer and dial indicator prove it.
 

Venice Motor Bikes

Custom Builder / Dealer/Los Angeles
Mar 20, 2008
7,266
1,797
113
Los Angeles, CA.
Im pretty sure that the seller is mistaken... From everything I know about these engines, there are indeed three different sizes... But they are 49cc, a mid size engine thats about 55cc & 66cc. (The 66cc is the one that was mistakenly called 80cc by the Chinese, but is really only 66cc).
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
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As far as we could tell, he is full of ****. He wouldn't respond to any of the messages I sent him and that photo is from another sellers website from when he had 50 60 and 80cc engines (47, 58, and 68cc)

So no that's a scam.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
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Littleton, Colorado
Buy one. Then measure the bore and stroke and you'll see the seller is scamming.

The term 80cc is a marketing ploy used by sellers to get the Internet search engines to take you to them. The idea of an 80cc engine uses an untraditional method for determining engine displacement by including the combustion chamber in the calculation. The only true way is to measure the bore and stroke and when you do that you'll see that the advertised "80cc" engine is actually not what is promised.

Tom
 

Geezer

Member
May 2, 2011
94
1
8
Illinois
thanks guys, I had a feeling this was BS... but i did learn something. I didn't realize there were 3 different sizes... always thought there was just 49cc and 66cc.
 

donphantasmo

Member
Oct 3, 2010
372
11
18
Middleburg, FL
Every few months, this same discussion comes up. There is no such thing as 80cc. If it makes you feel better to say that your bike is a 80 cc, while mine is a 66cc, then go ahead. lol.

They are all 49cc or 66cc.
 

Geezer

Member
May 2, 2011
94
1
8
Illinois
well don, i guess you didn't view the link i posted or read any of the previous posts... the link shows 3 different sized pistons & venice posted that there are indeed 3 different sizes just that none of them are truely 80cc. I realize there has been a lot of debate on what the true size of these engines are but it doesn't matter to me what they call them, i just want mine to all be the same size so that the parts are interchangeable...

they're all 49cc if you ask me :) at least thats what i'll be sayin if i ever get pulled over :)
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
252
63
up north now
Every few months, this same discussion comes up. There is no such thing as 80cc. If it makes you feel better to say that your bike is a 80 cc, while mine is a 66cc, then go ahead. lol.

They are all 49cc or 66cc.
Except for the 60cc(58cc) and 55cc(47cc)(45cc) engines. I have one of each.
 
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biknut

Well-Known Member
Sep 28, 2010
6,631
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Dallas
It's been common practice since the beginning of time for manufacturers to call their motors something they're not.

For years Sportsters were called 900s, but they were always 883s.
 

donphantasmo

Member
Oct 3, 2010
372
11
18
Middleburg, FL
well don, i guess you didn't view the link i posted or read any of the previous posts... the link shows 3 different sized pistons & venice posted that there are indeed 3 different sizes just that none of them are truely 80cc. I realize there has been a lot of debate on what the true size of these engines are but it doesn't matter to me what they call them, i just want mine to all be the same size so that the parts are interchangeable...

they're all 49cc if you ask me :) at least thats what i'll be sayin if i ever get pulled over :)


Geezer. I saw your post, and looked at your link. I didn't think the two on the right are very different. If they were, oops, my bad.

I have always had motorcycles waaaay before I even looked at motorizing bicycles.
BIKNUT was right, R1 is a 998. ZX6Rs are 636s.

But, some engines are pretty much close. The 49cc bikes are called 49cc because they're 49cc. 66cc is called 66cc, but often the 80cc motors are mistaken for 80cc, when they're actually 66cc.

Use the search tab, and look at the posts. There are a million other posts just like this one that say the same thing..