Clutch Springs, Torque Spring Questions By mikey34 (Read 720 times)

[mikey34]

I am going through one of my older QMB139's and I am wanting to upgrade the top end a little bit. I was wondering, would I want a higher RPM clutch spring setup, with higher torque spring? Do I NEED to keep them the same? Pro's-Con's?


ALL FEEDBACK WELCOME! PS- I am also upgrading the variator side with 8.5 gram weights, I am guessing this will help my TOP END, just take a little while to get there...

THANKS GUYS!!!!

[twowheeler]

LOl changing to 8.5 you can mail a letter to where your're going and it will get there faster!
Im guessing thats too heavy for stock for most and probably way to heavy when you mod the clutch.

[Bashan]

The clutch plate springs control when the clutch engages. Stronger springs take a higher RPM to engage which helps hole shots. Personally, I don't think it's a good idea to slam the scooter's components with a high RPM engagement and it would not help top end. .

A stronger torque spring holds the CVT in the lower gears longer giving you faster take off. These appear to be the best of both worlds by giving you faster lower gears but still providing the same top end. These will also not help top end.

Higher variator weights will help top end if the belt isn't getting all the way out on the drive pulley. Hey Alley, can you go over how you mark the pulley to check belt travel?

Have you considered changing the transmission gears to a higher ratio? If your engine can pull it you will definitely gain top end. Alley's also the expert on that upgrade.

[Alleyoop]

Mark your variator like this 1/2 inch by 1/2 inch and run it at Wide Open Throttle and see how much of a mark is left. That will give you something to work by. And show us the mark that is left on yours after the run.
Alleyoop

[mikey34]

OK guys will do as soon as I can, The scooter has a really strong engine, Uni Free Flow filter, #1.00 Main jet, Gutted muffler, it goes 43 as it is flat, and I can hit 50 down hill, but I wanna hit 55. I know, I need to just buy a 150cc... I know, but I have seen some youtube vids of the guys at 49ccScoot.com get these 50cc going 70mph, and I have NO CLUE what they've done to them, BBK?, Better Trany's, idk...

[mikey34]

AND to be honest guys, when you compare throwing so much money into a 50cc just to get to stock 150cc speeds, I think I fighting an uphill battle here...

www.ebay.com/itm/150cc-GY6-4-stroke-Long-Case-Engine-/141060705465?pt=Other_Vehicle_Parts&hash=item20d7df8cb9&vxp=mtr
I can get a 150cc Engine for $307.00, I know that it won't fit in the 50cc WITH OUT modification. I have found some nice dimensions on a Ruckus frame, and really there's not much to them, I will use the front end of a Honda Metropolitan, and fabricate the rear frame from tubular 1" prolly...

[Alleyoop]

Well since you say you have a strong motor then PUT IN SOME taller tranny gears and give it a shot.
You get a lot of BANG for the buck because they are not expensive at all. If you know what your current gearing is then go 2 up and 2 down that alone should get you about 8mph on the top end. You could maybe hit 55 with 3up and 3 down on the gearing.

Most 50cc scoots the gearing is:
15/51 -15/52

2up and 2down would be 17/49
3up and 3down would be 18/48


Alleyoop

[mikey34]

Thank you alley, I will be researching this... Do you actually change the gears in the scoot? Sorry if that sounds stupid, I am really new at CVT's...I really wish I could throw an 80cc dirt bike and tranny in one of these frames!!! hahaha

[mikey34]

Since I will be changing my gear ratio, do you know where I can purchase them from?? THANKS ALLEY

[Alleyoop]

Google for them for you motor the prices will vary, here are some:
Alleyoop

www.racingplanetusa.com/secondary-transmission-gear-naraku-139qmbqma-p-8550-1.html?cPath=7490&sessID=b7a78015ad7d8

[mikey34]

Let me know if there is anything that can be done Alley, but, I am pretty sure its gonna have to be like you said, new gear ratio, or bigger bike... INNER VARI-PULLEY

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[mikey34]

OUTER

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[mikey34]

I Found out that my starter flywheel had a screw come out of the counter-weight, and got pretty thrashed...

BTW, I Lithium Greased Everything in here...

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[mike6736]

Well!! Fast easy fix... Should be a lot less noise too. I remember this happen on another scoot

Magoo

[LUKE]

put one drop of blue locktite on each of those three screws and your good to go...