Page 1 of 2

Re: Rpm drops with speed increase.

Posted: Tue Jun 26, 2012 4:08 pm
by spkrboxx
I am dealing with the exact same thing with mine
check my thread, people have been helpful
viewtopic.php?f=4&t=23846

Re: Rpm drops with speed increase.

Posted: Tue Jun 26, 2012 4:59 pm
by Wheelman-111
Greetings:

I've found that springs grow soft with age, cycling, and heat. Replace the spring or go down 3 grams or so total weight. (You now have 42 grams, so consider 38-40 and test.)

It seems like worn rollers can have the same RPM-dropping effect?

Re: Rpm drops with speed increase.

Posted: Wed Jun 27, 2012 11:23 am
by dv/dt
What wheelman said. You need a new or stronger center spring.

Re: Rpm drops with speed increase.

Posted: Wed Jun 27, 2012 1:12 pm
by Bear45-70
Or it could be a lack of horsepower to pull the final gear.

Re: Rpm drops with speed increase.

Posted: Wed Jun 27, 2012 1:16 pm
by swimmingfree
bear cood be right you need to do a compression test .. it well tell us more ...
swimmingfree

Re: Rpm drops with speed increase.

Posted: Wed Jun 27, 2012 6:34 pm
by Wheelman-111
Greetings:

I don't buy the "underpowered" thing. If you don't have the power to max the variator, it just keeps in a lower "belt-gear" and the RPM stays up, UNLESS you have too much weight in the vario for the spring. So try dropping 3 grams at a time until it's sweet.

Re: Rpm drops with speed increase.

Posted: Wed Jun 27, 2012 7:54 pm
by Dio89Elite
yup, play with the weights... your setup still needs fine tuning.
still looking to hit that sweet spot ;)
well... that's just my opinion. :mrgreen:

Re: Rpm drops with speed increase.

Posted: Wed Jun 27, 2012 9:29 pm
by Wheelman-111
Greetings:

This ain't that hard. Drop 3 grams, gain about 500 RPM. The variator/spring balance does not change depending on what gears are in the case.

Re: Rpm drops with speed increase.

Posted: Wed Jun 27, 2012 10:59 pm
by Wheelman-111
Greetings:

6x7 = 42. Try 39, 36, etc. until the RPM stays where you want it.

Re: Rpm drops with speed increase.

Posted: Thu Jun 28, 2012 1:36 pm
by scottinscotty
i have noticed that too stiff a center spring and you'll loose rpm.. the variator and rear clutch timing have to be pretty precise.. if the center spring is too stiff i strains the engine and will cause it not to "rev" up

Re: Rpm drops with speed increase.

Posted: Thu Jun 28, 2012 5:55 pm
by Wheelman-111
Greetings:

Quoth ScootinScotty:
i have noticed that too stiff a center spring and you'll loose rpm.. the variator and rear clutch timing have to be pretty precise.. if the center spring is too stiff i strains the engine and will cause it not to "rev" up
Huh? I disagree, completely! A stiffer spring keeps the vario from shifting up, so it stays longer in a lower "Gear" for a given variator load. RPMs stay UP, not down.

Re: Rpm drops with speed increase.

Posted: Thu Jun 28, 2012 6:55 pm
by scottinscotty
i agree, and disagree... only due to the fact that when you max out your variator and the clutch is too hard to open it will strain your engine and cause the rpm's to lower with the strain of the clutch.. my cousin had this same issue... the scooter was a rocket, up untill the variator maxed out and his 3000 center spring caused to much strain on the engine to allow it to go anyfaster.. and it' actually bogged down the scooter witch he thought was a jetting issue.

Re: Rpm drops with speed increase.

Posted: Thu Jun 28, 2012 7:02 pm
by scottinscotty
i like to run a 1000 center.. only because i have tried other spring sizes and i think that the 1000 put's the least strain on my drive train and provides the best performance... with my set-up

Re: Rpm drops with speed increase.

Posted: Thu Jun 28, 2012 11:03 pm
by paulpauly7
try 6x6.5g rollers if no good try 3x6g and 3x6.5g

Re: Rpm drops with speed increase.

Posted: Fri Jun 29, 2012 12:34 am
by Trafficjamz
What pipe do you have?

do you have a tach?