No top end By bigscoot150 (Read 2,978 times)

[bigscoot150]

I got a 150cc gy6 scooter. Changed the rollers to 13 grms while i was replacing the belt and clutch bell. Also went up to and 110 jet and a cold air filter and eliminated the air box. I am better on the bottom end but still i have no top end speed. I ride with two guys with same size motors and they whip my rump on straightways. Anyone got any suggestions.

[sprocket]

Probably carb tuning...might try a decent CDI with spark adjustment...

May change to a free flow exhaust...

Even two scooters of the exact brand and model will perform differently.. just the way it is...

[Bashan]

Do you have a tach? You need to see what kind of RPMs you're turning at WOT. You may have a RPM restrictive CDI. Rich

[bigscoot150]

turning 8000rpm at about 62mph. The other 2 scoots are running over 70 and arent pushing as many rpm's at all.

[Alleyoop]

Well their speedo might say 70 but I guarantee they are no way near that unless they have those suckers modded to the hilt. The 150s are good for 50+ maybe 60 and the speedos are way off on the high side. Check your Variator and see if it is the same size as your front pulley. The Variator might be smaller and the belt will only climb as high as the smallest face.
If your Variator is only 4" across you could get a performance Variator which is 4 1/2" across and if you get the belt to climb to about 1/8 from the edge you will pick up 4-5 more mph on the top end.

Also check your current Variator and see high high your belt is climbing. Mark the Variator and see how much of a mark is left after a WOT run.
Alleyoop

[sprocket]

What are the other two scooters...Kymcos or CFMoto EFI's?

Very different animals to the GY6

If you are doing 62 mph on the Chinometer then you are probably doing 56-8 GPS. That is about tops on a stock GY6 without lots of mods or BBK. As Alley mentioned you might get a gain from the variator and weights or sliders...

[bigscoot150]

thanks alley. i'll try that. I thought about changing the variator when i changed the rollers but i figured lets see what i got first. I'm not wanting to go the speed of sound but i would like the pep those other 2 have. also when should i adjust the valve's. I got 1800 miles on it.

[bigscoot150]

doc all i know is mine is a 2008 tao tao gy6 150. i think theres is 2 but they are 3 years newer. all say vip on them and the motors look the same. there is slight differences on the airbox makeup and on my carb i have screws in the cover where the jet is where theres rivoted

[sprocket]

The valves should have been adjusted at about 800 miles and again at about 1500-2000

You could be loosing power

[sprocket]

OK so they are all GY6s.. but 2-3 years is a big difference.. they could have better electrical and lighter frames deeper head with larger valves, different exhausts...all kinds of things could make them go faster.. but they aren't doing 70MPH GPS...unless they are running off a cliff ;-)

[bigscoot150]

sprocket i was thinking the probably needed adjusting but i got to find out what the adjustments are. sprocket lol to funny on the cliff joke. i know the exhaust are the same as far as valves and go have no idea. the weight of the scoots are the same i have rode theres and theres no difference weight wise.

[sprocket]

The intake valve (top one) is set to .004INCH and the exhaust (bottom) is set to .005INCH.

I would set your valves and adjust your air/fuel mixture.

Also run 87AKI octane fuel (regular)...you will get more power...

After that and tuning the CVT it is engine modifications

[Bashan]

I think Sprocket brought this up on a thread a while back but I couldn't find it. Maybe he can clue us in a bit more on this topic. Apparently some scooters have a restriction collar between the pulleys of the variator. It keeps the plates from coming all the way together. I've never seen one on any of my bikes. Here's a pic and a video:

8K is pretty good on the RPMs but I like to get about 8.2 0r 8.3K. Still, those guys shouldn't be walking away from you. A Kymco or CF would definitely be faster but shouldn't mop the floor with you. I'm also wondering if you might have some bastard tranny gears for some reason. Alley is da man on that topic. Rich

[roketafan]

all those little mods time for a no rev cdi and a perf muffler i have a stock muffler mod u just need a pop rivet gun and a drill

[sprocket]

Rich those washers are on some 50cc, I have never seen them on a 150cc