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rebel101150
01-28-2014, 12:43 AM
while running I can only hit 6k and redline isn't even until far past there. I have an 08 VIP future champion scooter. even on the stand it doesnt rev past there. it will hit a little past 60mph even hanging at 6k, can i remove this limit? didn't think 150's would have a rev limit.

gitsum
01-28-2014, 12:44 PM
8000 rpm's is about as far as you should push a GY6 if you want it to last. On a 125/150cc engine the max horsepower is probably closer to 7000 rpm's. If you do a lot of longer highway rides 7000 rpm's is a safer guideline.

Most 150cc scooter don't have a rev limiter. The first step would be to try lighter variator weights. You want the engine to pull 6500 - 7000 or so rpm's under full throttle, probably no more than 7500 rpm's at top speed on level ground with a favorable tail wind. I wouldn't advise running WOT for extended distances.

It wouldn't hurt to check the carb tuning, chances are it is set up borderline lean. 60 mph on the speedo is probably closer to an actual 50 - 53 mph.

rebel101150
01-28-2014, 01:12 PM
8000 rpm's is about as far as you should push a GY6 if you want it to last. On a 125/150cc engine the max horsepower is probably closer to 7000 rpm's. If you do a lot of longer highway rides 7000 rpm's is a safer guideline.

Most 150cc scooter don't have a rev limiter. The first step would be to try lighter variator weights. You want the engine to pull 6500 - 7000 or so rpm's under full throttle, probably no more than 7500 rpm's at top speed on level ground with a favorable tail wind. I wouldn't advise running WOT for extended distances.

It wouldn't hurt to check the carb tuning, chances are it is set up borderline lean. 60 mph on the speedo is probably closer to an actual 50 - 53 mph.

seems like no matter what I do, even sitting on the stand it revs to 6k. It does seem slightly lean, I get a pop from the exhaust every now and then. would it keep revving or stop from there?

and how would I go about adjusting the weights?

skuttadawg
01-29-2014, 11:54 PM
I would first check the airfilter and jets in the carb to see if they need cleaning . Popping from high RPMs is lean misfire which means your a lil lean . To fix that you simply replace the factory main jet with a size or two larger on like in this jet kit here http://www.partsforscooters.com/114-48-Main-Jet-Kit-CVK?sc=34&category=133078


You need to remove the CVT and then the variator in order to remove and weigh the rollers to see you have . A gram or two lighter can help on take off and uphill and often top end if the RPMs get higher than with heavier ones . Too light and you will loose speed . Get a weight set kit like here so you can try various weights http://enviromoto.ecrater.com/p/14177965/prima-roller-weight-kit-18-x-14

Could have some cloggage in the exhaust pipe . Does your needle in the carb have an adjustable clip ? Do you have an air/fuel screw that you can adjust ?

Here is some tuning tips http://www.provoscooter.com/tuning

rebel101150
02-02-2014, 09:16 PM
Multiple issues caused it but it's resolved now for the most part. The popping was someone welded a damn mini chopper exhaust onto it, getting a performance pipe soon. The rev limiting was a bad relay connection which has recently been repaired.