Rev limiter indications? By new2scooters (Read 637 times)

[new2scooters]

Just curious as to what the indications are for a rev limited CDI? Reason I am asking is I have no additional speed gained from 1/2 throttle to full throttle. Even at 1/2 throttle I am pleased with the speed, indicated on speedometer at 50kmh with engine not even laboring nor really reving to any extent, but am just curious if this is an indication of a rev limiter in action. It doesn't spit, cough, misfire, etc.... and seems as if it is just running fine, just no faster.

Thanks

Bill

[sprocket]

There probably isn't a rev limiter if it is a 150cc...but you should be getting power increases from 1/2 to WOT however.. something isn't right maybe the throttle cable needs adjusting? Other thoughts are the pick-up coil is topping out or the CDI maybe getting old and the capacitors aren't charging fast enough anymore...

[Alleyoop]

Or the weights are to heavy which will limit the rpms.
Alleyoop

[new2scooters]

Apr 15, 2012 13:04:35 GMT -6 sprocket said:

There probably isn't a rev limiter if it is a 150cc...but you should be getting power increases from 1/2 to WOT however.. something isn't right maybe the throttle cable needs adjusting? Other thoughts are the pick-up coil is topping out or the CDI maybe getting old and the capacitors aren't charging fast enough anymore...

Thanks for the reply. It is appreciated. The CDI came from the JMStar donor scooter and the engine is 50cc. I have ordered a new performance CDI from ScrappyDog Scooters just to have a spare on hand but will install it when it arrives to see if it makes a difference. As for the throttle cable, I just checked and the throttle is rotating all the way to the stop on the carb.

Thanks again.
Bill

[new2scooters]

Apr 15, 2012 13:24:46 GMT -6 Alleyoop said:

Or the weights are to heavy which will limit the rpms.
Alleyoop

Thanks for the reply Alley. I'll add your comment to my list of things to check.

Thanks again.

Bill

[sprocket]

Could be a flakey pick-up coil but I would also investigate the variator weights as Alley suggested...

Still when you are 1/2 throttle and you give it more gas... the engine revs should increase...if the engine revs go up but you go no faster then you need lighter weights...

The weights, in effect, shift the power curve of the engine...

[cdoublejj]

why a performance CDI?

[sprocket]

True performance CDIs from companies like NCY have larger capacitors, they jack the spark voltage, can operate at higher RPMS and they may have some spark advance...but they are expensive.

95% of people that use them find no difference from stock...however they are very reliable.. that is why I use one.

www.scootertronics.com/ncycdi.html

They have no rev limiter which is true but most stock CDIs don't have rev limiters now either...

[new2scooters]

Apr 15, 2012 13:24:46 GMT -6 Alleyoop said:

Or the weights are to heavy which will limit the rpms.
Alleyoop

Thanks Alley and Sprocket Your advice was exactly correct. I just changed the roller weights and went to 5.8 gram from 6.5 and it made a world of difference. It has really helped with the scoots ability to climb hills and engine seems to have more power since it is in the power band.... Thanks again!

Bill