50 C.C. faster than 80 C.C. !?!?!?!?

Hi... my suzuki minicross (4 speed) used to keep up with a 6 speed 50cc (6 speed all standard and mine with tuning exhaust and air filter) now i have changed the rear wheel from 17" to 18", the sprocket from 42 to 40, and now it is quicker than the bike i raced before, and than most 80 C.C.s. Explanation????

Also would it be a huge improvement to run a 35 tooth rear with the 14 front, and an 80cc kit??

Re: 50 C.C. faster than 80 C.C. !?!?!?!?


Different timings, different gearbox, different exhaust, different carb....

Everything different.

A 50cc bike can go up to 140MPH (It has been done) depending on how it is build.

The minicross is build for speed, not for reliability. A normal moped is build for reliability, not for speed. This is a huge difference.

Depending on how the 50cc and 80cc is timed, the other components used and the ratio of the transmission, a 50cc can be faster then a 80cc.

Why you're bike is quicker now, is because you actively increased the gear ratio. You fitted a larger wheel and you increased the amount of turns it makes per rev (Longer gear ratio) so you've increased the top speed. You can only do this so far as you have enough power in the bike to pull that ratio. A 35 tooth sprocket might be pushing it, but I don't know how much power you have left.

One thing is for sure: If you install a longer ratio, you will reduce acceleration.

Re: 50 C.C. faster than 80 C.C. !?!?!?!?

Longer ratios will also reduce the amount of torque delivered to the rear wheel. if you're a fat ass, you may not be able to hit the top speed possible. if you drop the gearing down you could potentially increase your usable speed because there is enough torque to move you

Re: 50 C.C. faster than 80 C.C. !?!?!?!?

rpm is what it is all about. a husqvarna 42cc chain saw will hit 15000 rpm - hugely way above what you are playing with but the torque is low and flat so you probably couldnt get the bike enough to get out of its own way.

Re: 50 C.C. faster than 80 C.C. !?!?!?!?

suzuki minicrosses remind me of derbi's

Re: 50 C.C. faster than 80 C.C. !?!?!?!?

Haha I weigh 280 and my chappy is moving at 43mph. I wonder how fast it would go if we put my friend deane on it who is 103.

Re: 50 C.C. faster than 80 C.C. !?!?!?!?

Probably not that much more. The engine size along with the exhaust seems to limit top speed, downhill or uphill. A 50 cc moped could probably do highway speed, if the exhaust and motor were properly tuned.

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