50cc or the 80cc?

[MelvinSWE]

I was thinking of buying a kit for my bike ...
Wondering if I should have 50cc or 80cc. The website claims that the 50cc engine has a top speed of 19 mph or 30 km / h. Feels like it should go faster?
And 80cc it says it should do 25 mph or 40 km / h. It also feels like it should go faster without modification.
Am I right? And yeah. It is a Chinese kit!

 

[MelvinSWE]

Both are wrong on speeds. The 80cc is actually 66cc.

Everyone gets the 66cc (80cc) as their is the biggest selection of parts.

The 66cc (80cc) and 49cc (50cc) is hard to visually tell apart and a replacement 50cc label on it makes it much safer unless it gets inspected.

So. whats the topspeed of the 50 and 80cc?

 

[Street Ryderz]

Big misconception here and the usual incorrect displacement's the smaller one is 48 cc and the bigger one 66-69cc both come with the same gearing and both will do the same speed being geared the same and having the same rpm potential, reworked the 48 cc can out run the 66-69cc stock or even slightly modified. You can turn the 48cc into a true 50 by swapping out the crank to the 40mm stroke and with a bit of work on the jug make a very strong better on gas performance engine that actually run's a bit smoother and if not over geared unload's or rev's up faster.

 

[MelvinSWE]

Okay, I mean that the website (Banggood) claims that is going 19 and 25 mph. Just wondered if it does going faster. Cause 19 and 25 mph is not much for a 50cc and a 66cc engine

 

[Chainlube]

Okay, I mean that the website (Banggood) claims that is going 19 and 25 mph. Just wondered if it does going faster. Cause 19 and 25 mph is not much for a 50cc and a 66cc engine

Most likely those speed claims are for legal purposes, people will just buy the smaller motor if they know it won't go over the legal limit for a motorized bike. So they say 25 for the bigger cc motor so people will buy them.

My 48 cc Auto-Mini will do 40 k/h or 25 m/h with no mods and 20" wheel.

 

[Axl Myk]

For the difference of what, $20 between the 49 and 66cc, get the 66/80.
Both motors rev the same, it's just that the 66 MIGHT get you to speed a little quicker.
With the supplied 44 tooth sprocket and a 26" bike 30mph is doable.

 

[YetiWoodz]

Nice thing about these engines is that you can make them go much faster than stock. Stock is no less than 25 mph. Plenty of modifications you can do some of the best being jetting, porting, adding an expansion chamber, you can go into the 40s mph. Takes time, its a neat hobby to work on these engines if your up to it. We all modify them, got plently of good info here on this forum and knowledgeable people to guide you. Personally, I'd go with the 66cc as mentioned there's more part selection.

 

[Will'smotobikes19]

49cc with a 4g is a good combo easily get 30+ mph.

 

[DAMIEN1307]

49cc with a 4g is a good combo easily get 30+ mph.

OK...totally confused here with the lingo "4g"...im used to Computer lingo where 4g means 4 gigs as in gigabits or gigabytes...what does 4g's mean in this context???...lol...DAMIEN

 

[Will'smotobikes19]