why did it slow down?

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bryguyinuyasha
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why did it slow down?

Post by bryguyinuyasha »

Ok,

I installed a no rev limiter and I noticed a increase in speed. Then I put on a "performance" clutch, a 2000 rpm clutch spring, and lastly 9g weighs. Its on a 50cc gy6 Chinese motor. When I was taking the clutch apart I somehow managed to bend the pully thing. I bent them back slowly, they are almost the same, just a bit off in 2 little spots. But its not that bad.

I thought that the rollers might just be to heavy, so I went on a straight away and just let it open all up. Before the 9g weights, the clutch, and clutch spring I had it going 30, now its going 20-22. :(

Any Advice?
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Wheelman-111
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Honest Reporting on the Forum

Post by Wheelman-111 »

Greetings:

Yesterday you posted this in Builds:
OK,

I put the new CDI in and I got a 8mph boost with a passenger. I got a 12mph boost with just me
Im putting the 9g weights, the perf. clutch, and the new spring on tomorrow
So what you're saying, if it went 30 for a while, is that your previous top speed was, uhh... 18MPH? And now you're going 20-22? If so you're still ahead of the game!

If not, we can't really help you if you let pride in your accomplishments prevent you from accurately reporting your results.
I believe I cautioned you about changing rollers and spring at the same time.
I'd also advise caution in changing both the rollers and the spring, unless you're following a proven "recipe" amongst the GY-6 Cognisenti. These are two complementary variables; A stronger spring makes it rev higher and lighter rollers also raise RPM. It can leave a feller right flummoxed if the simultaneous swap kills performance. If you're breaking new ground, consider just swapping one or the other and see if you like it better. The rollers are less work.
It now sounds like your stronger +2000 spring is preventing your lighter rollers from shifting the variator all the way through, leaving you stuck in "second gear". Put your heavier stock weights back in and see if that's enough. If not, get rid of that spring if you can. If your pulleys are wobbly, see if you can get them perfect or replace the assembly.

And let us know what really happens. The truth shall set you (or at least your scooter...) Free. Lastly, remember you can always...

Dude! Swap in a Dio!!
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
bryguyinuyasha
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Re: Honest Reporting on the Forum

Post by bryguyinuyasha »

Wheelman-111 wrote:Greetings:

Yesterday you posted this in Builds:
OK,

I put the new CDI in and I got a 8mph boost with a passenger. I got a 12mph boost with just me
Im putting the 9g weights, the perf. clutch, and the new spring on tomorrow
So what you're saying, if it went 30 for a while, is that your previous top speed was, uhh... 18MPH? And now you're going 20-22? If so you're still ahead of the game!

If not, we can't really help you if you let pride in your accomplishments prevent you from accurately reporting your results.
I believe I cautioned you about changing rollers and spring at the same time.
I'd also advise caution in changing both the rollers and the spring, unless you're following a proven "recipe" amongst the GY-6 Cognisenti. These are two complementary variables; A stronger spring makes it rev higher and lighter rollers also raise RPM. It can leave a feller right flummoxed if the simultaneous swap kills performance. If you're breaking new ground, consider just swapping one or the other and see if you like it better. The rollers are less work.
It now sounds like your stronger +2000 spring is preventing your lighter rollers from shifting the variator all the way through, leaving you stuck in "second gear". Put your heavier stock weights back in and see if that's enough. If not, get rid of that spring if you can. If your pulleys are wobbly, see if you can get them perfect or replace the assembly.

And let us know what really happens. The truth shall set you (or at least your scooter...) Free. Lastly, remember you can always...

Dude! Swap in a Dio!!
I didnt notice the post about changing both. I dont know how heavy the stock ones were but they were in great shape. Its pouring rain here so I'll have to wait. I'll put the stock ones in and see what I can do. Im guessing it is stuck in 2nd.

Im confussed as to what the clutch does. I understand the concept, but what is the purpose of the pads on it?
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Wheelman-111
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Clutching Lesson

Post by Wheelman-111 »

Greetings:

Next time you have your belt off, give that rear pulley a spin with your hand and watch it freewheel for several seconds. Thats what the motor turns. Now spin the clutch bell and notice that it moves your back wheel. The clutch pads connect the two.

The speed of engagement is controlled by a balance between the centrifugal force of the pad "shoes" and the grab springs retracting them. Except for a trivial amount of slip, once the clutch engages it becomes a solid connection between the rear wheel and the driven pulley, hence the engine's power.

Unlike your old snowmobiles, (where belt slip is the "clutch" interface) the variator independently controls the ratio between the crank and that clutch shaft. The belt is always tight to those pulleys, and doesn't slip nearly as much as a snowmobile's either.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
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bryguyinuyasha
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Re: Clutching Lesson

Post by bryguyinuyasha »

Wheelman-111 wrote:Greetings:

Next time you have your belt off, give that rear pulley a spin with your hand and watch it freewheel for several seconds. Thats what the motor turns. Now spin the clutch bell and notice that it moves your back wheel. The clutch pads connect the two.

The speed of engagement is controlled by a balance between the centrifugal force of the pad "shoes" and the grab springs retracting them. Except for a trivial amount of slip, once the clutch engages it becomes a solid connection between the rear wheel and the driven pulley, hence the engine's power.

Unlike your old snowmobiles, (where belt slip is the "clutch" interface) the variator independently controls the ratio between the crank and that clutch shaft. The belt is always tight to those pulleys, and doesn't slip nearly as much as a snowmobile's either.
oh, Thanks!
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Re: why did it slow down?

Post by burnt_toast »

well if the revs have gone down, then you still need to less weights. straight away wont matter much if you dont have power to push the pulley

also please post in correct forum
projects galore :nerd:
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