Finding Contra Spring / Clutch Trouble

[vacationer]

Recently I became unable to push my scooter by hand while the engine was turned off. It would just lock up entirely. I found I was able to fix this problem by spraying WD40 into face of the clutch. Now, I've found that the scooter drives very sluggishly if I don't spray WD40 onto the clutch every few miles. I took the clutch apart to see if anything was clearly wrong but didn't find anything obvious. (I don't doubt that the WD40 has loosened some of the grease thats supposed to be inside the clutch.)

Anyways, I still need take the torque driver apart and inspect it but I'm mostly concerned about the spring after watching one of Brent's videos. He said that I ought to check the length of my spring and compare it to the manual. Currently, mine is about 110mm. The manual says it should be 94mm. 

That said, the scooter was modded a bit by its last owner (70cc big bore, changed the drive gear, new rollers too maybe), so I don't know if the current spring matches the original manufacturer spring. The current one is black and says on it: Stage6 3.6mm x 53.7mm medium.

I can't find another one online anywhere that has these specifications exactly, so I can't tell if this one is stretched or not, but I'm hoping to get one that matches this one rather than what the manual recommends (if the two differ at all). 

What do y'all suggest I do? And is the spring really the problem?

[Zino]

Sounds like a torque driver that is sticking .
Take the spring off and check the open and close by turning it clock wise and counter clock wise functions and see if it opens smoothly.
I would then take it apart and regrease it
Check the guides and pins
Retest it via the open and closing method see if it feels smoother .

Reinstall it

As far as spring tension the medium springs my unscientific method is how hard are they to compress on install.
The lightest springs I can compress easily on the torque driver with just my fingers when I am installing the belt.
The medium springs are a little tougher to compress ,I can do it by myself but appreciate help from my son .
The stiff springs require help .

I also can tell when I compress the spring with my feet when I put on the clutch nut .
The light springs are super easy to compress ( IF i didnt care about safety I could do them with one hand and use the other to put on the nut)
The medium springs require a little more force and there is no way I could do them one handed

[snaker]

Symptoms sound to me like something in the drivetrain on/after the clutch
Hanging up wheel bearings
Hanging up brake
Messed up gearbox
Hanging up driven pulley idler bearings
Clutch itself, clutch springs

Start inspecting and separating

[vacationer]

Zino I took the clutch apart and regreased it. No obvious problems there but nothing changed after I put it back together. The spring is definitely a medium. Just don't know if it's the same length it used to be.

snaker I'm worried I'll be going down a rabbit hole soon enough. Just tried to find out what oil to put in the gearbox if I take it apart and put it back together, and 30 minutes later I have a dozen questions about tranmission fluid, gear oil, motor oil, different ratings, etc. Plus I'm not sure if I'll know the problem when I see it. This would be a lot simpler if the scooter didn't already have so many mods when I bought it.

But the fact that the scooter accelerates a bit when the WD40 hits the clutch face should signal something more specific, no?

[aeroxbud]

If it's that bad I would have thought it should be quite obvious on inspection.
How many miles has the scooter done? The spring should be good for thousands of miles?
Could it possibly be the variator sticking. Giving you symptoms like the clutch.
If you have been spraying WD40 into the clutch. The pads are probably contaminated by now.

[snaker]

Aerox, gotta admit, when I read WD-40 on the clutch, I thought, no way.
Now I'm not so sure.

And just to be clear for the op, the spring(s) at issue for this issue, are the three small clutch springs (assuming this rig has 3)
Not the big contra spring.

This might be one of those times when all have to be on the same page:
The centrifugal clutch is the part piggy backed on the driven pulley.

[vacationer]

aeroxbud It's a 2000 so... a lot? Wish I could give you a number. But there's no telling when the spring was last replaced. I'm happy to replace it but ideally I'd find the same one that's in there now.

What causes the variator to stick? The previous rollers had flat spots but that was true before this problem and I've since replaced the rollers (only after the WD40 treatment began). Pretty sure the belt is fine but, as I said above, I want to see if I can narrow down the problem before I go about replacing everything one part at a time.

At the time I first did the WD40, I sprayed both the brake (the lever part that sits behind the transmission - not the pads or calipers themselves) and the clutch. Then the problem stopped. It was a mistake to try both at the same time since now I can't tell which was the cause, but is it possible that the brake was the problem and that I simultaneously screwed up the clutch in the process?

snaker What makes you think the small springs are the issue? Are you thinking maybe the clutch isn't fully opening?

[sinfull]

With the clutch off the bike, can you push the bike with out it locked up ?? Once reinstall it locks up ??

[vacationer]

sinfull It actually doesn't lock up at all ever since the first time I used the WD40.

[vacationer]

So I bought a new clutch. Speed improved a little bit. Acceleration definitely improved. Still dragging though. I don't know what strength the springs were on the old clutch but I bought a pack to try out a few strengths on the new clutch.

A few things I noticed, though. One, the scooter has been very loud since this all started, but the sound gets a bit quieter and lower when the WD40 hits the clutch. Also, scooter seems to run better when cold. That and the WD40 situation tell me that heat may be the cause of my troubles but I have no idea how. Lastly, There seems to be a moment when I'm decelerating, near to stopping, when the scooter feels like it's dragging just a little less. I don't know how to explain it but it suddenly feels as though it's rolling by its own momentum rather than being powered. I also don't get as fast going downhill as I feel like I should.

So I'm getting the impression that something's actually holding the scooter back from using the power that the engine is generating. That would explain the loudness. Lots of RPM but not translating to speed. If I'm right about the feeling during decelerating, then maybe what I'm feeling is the clutch disengaging. Is it possible that the WD40 was helping to decouple the clutch and the bell, thereby releasing whatever it is that's holding the speed down and thus letting the wheels roll more freely?

I just don't understand the change in sound when I use the WD40. If something wrong in the clutch is causing a change upstream, I imagine it would be the friction causing the engine to work more slowly and therefore making it quieter and lower rather than louder and higher.

[90GTVert]

Maybe the spacing is wrong for the clutch. That can sort of join the gearbox and the CVT/engine if the clutch bell is not spaced out enough. It's normally only a thing with aftermarket clutches, but it's a fairly quick check. The bell should be able to rotate freely without contacting the clutch. If not, spacing may be off. Could be other things, but you may have found those with past inspections... broken spring or shoe.

[aeroxbud]

It's quite normal for the clutch to grip better when it's cold. The CVT can get very hot, this has an effect on everything inside the cover.
What you are feeling when you come to a near stop is also normal. It's the clutch disengagement.
The springs are probably a different strength to your original ones. Making it feel slightly different.

[vacationer]

Spacing appears to be fine. I just took the clutch apart and put some more grease on the little pegs inside - whatever those are called. I also cleaned out the inside faces of the pulleys. That was more difficult than expected. Took parts cleaner and some elbow grease. I'm sure that was doing me no good. Ever since I started with the WD40, the inside of the transmission case has just been an even glossy black. I have no idea where all the grease had been hiding but I wiped up as much as I could just now so the pulleys don't get dirty again.

Anyways, I put everything back together without changing the springs and took it out and it seems faster already.

Also, when I measured the belt recently, it seemed fine but I just compared it to a new one and it might be time for a change. So I'll change that before I try different springs and see what happens.

Out of curiosity, the contra spring isn't meant to spin, right? I can't imagine it would even make a difference whether it did or didn't.

[aeroxbud]

The contra spring should always be under some sort of tension. Otherwise it wouldn't have enough strength the force the pulley closed.

[vacationer]

So it looks like it was, in fact, the belt. I don't know why the sluggishness coincided with the locking up and the WD40 but she drives just fine now.