Increasing the CC of the super 8 150

[skishades]

I have been coming across several upgrades for the GY6 motor.  A local scooter shop had a 200cc upgrade kit for my 150.  How effective are these kits?  I am assuming they are street legal but I was curious what else I would need to change.  I am assuming I would have to rejet the carbs, change the belt to Kevlar, likely a new pipe to reduce restrictions at the exit.  Do I need to change the weights or the variator too?  I haven't seen anything in the forum about increasing the CC for performance but I don't want to rely on the word of a salemen trying to sell me parts.

[Vivo]

Turbo it!!! http://www.mbe-motorsports.com/catalog/images/thumbs/small_VZ21_turbo_GY6_motorcycle_scooter_dirtbike_atv.jpg

[zombie]

At the 150cc level you would gain MORE by doing the carb/pipe/cvt than you would by going with a cc kit. Get all the goodies for a 150, and you will be blowing away all the other scoots. The BBK for a 150 will add about 7-8 mph, and 2ish seconds in an 1/8 mile but the goodies can get 15mph, and 4 seconds off the 1/8th. If you do both you'd have a rocket but it may not last unless you spend major dollars on quality parts. I njust started getting all the bits for 2 engines (50cc) and spent close to 2g's. For the bbk/bits I'd figure 2g's for a quality 200cc set up, for just good 150 parts about 800-1'000.

[dudley]

Guy on another forum added a bbk to his 150.(very good mechanic)made it a 170cc.
Result was an extra 3 mph. It just is usually not worth it.
Performance variator got me 4.5 extra mph. And that is with the same weights.
If you can't get the speed you want with cvt upgrades you really are better off with a bigger scoot.
On the other hand if you like wrenching, by all means go for it and keep us posted.

[wordslinger]

Insert Quote

Guy on another forum added a bbk to his 150.(very good mechanic)made it a 170cc.
Result was an extra 3 mph. It just is usually not worth it


...that's a shame...sounds like he didnt compensate the cvt...

[zombie]

It's really physics. If you want to double speed you need 100 times the power. Small changes effect a 50cc scoot MUCH more than a 150cc. I suck at math but going from 39mm piston to a 50mm piston is an increase of 22%. A 150cc is 57mm to a 170 which is 60mm for an increase of 1.5%. It's easy to say it don't do much good. If my numbers are wrong I would sure like to know. Thanks...

[wordslinger]

It's really physics. If you want to double speed you need 100 times the power. Small changes effect a 50cc scoot MUCH more than a 150cc. I suck at math but going from 39mm piston to a 50mm piston is an increase of 22%. A 150cc is 57mm to a 170 which is 60mm for an increase of 1.5%. It's easy to say it don't do much good. If my numbers are wrong I would sure like to know. Thanks...

..150s kick my ass top end...with my fleet of 50s....

...but i got them off th line!!!

[zombie]

Hit, and run poster!!!

[wordslinger]

...lika ninja......


       

[dudley]

Is it a true 200cc kit or actually closer to 180?
Get a good performance variator and try that first.
How fast do you want to go? And how long do you want your bike to last.
Ask yourself why a factory 200cc only goes 5-7 mph faster than a 150.
How much work to tune, re- tune, and tune again.
You might have to go with taller gears to really see the top speed benefits.
Almost all added power is used up fighting increased wind resistance and drag.
Not trying to talk you out of this. If you enjoy the tinkering I wish you well.
But if you are looking for a simple way to get sportsbike performance from a scooter there is not one.

[skishades]

I bought my scooter as something very practical and intend to keep it that way.  Not changing a thing at the moment... I will be adding a box on the back and I am tinkering with the idea of making a windshield but that is it.  I saw a kit at a scooter store for the GY6 motor to make it a 200cc.  I asked the saleman the same thing... is it 200 or 180? I have heard of the 180, read about it in the forums but I hadn't heard of the 200cc kit... anywhere.  The saleman insisted it was a 200cc kit and not the 180 kit.  I didn't know if it was something new or just the 180 with a 200 written on the tag.  I don't really trust salemen... which was I asked about it.  I also figured if it was a 200cc kit... someone might actually be interested or have tried it out.  Currently my scooter just does 55mph (speedo says 60)... and the road speed limits are 55mph. Its perfect as is.  No speeding tickets this month ... not the case for my wife in her car... and I am going to keep it that way

[tjupille]

First of all, the GY6 150 engine is actually a big-bore kit on what was originally a 125 (the Super 8 is a 125 in most of the world outside North America). That means there's not *that* much more room for improvement. Basically, our 150cc engines have a cylinder bore of 57 mm. The biggest replacement cylinder you can get that doesn't require machining the crankcase would be 59 mm (which gives 160 cc). The biggest available that I know of is 63 mm (which gives 180 cc).

If you really want to go faster, the cheapest approach is to sell the Super 8 and get a bigger scooter  .

By the way, a good source for performance parts is ScrappyDog (http://www.scrappydogscooters.com/125_150cc_Performance.html).