SHUDDERING AT SLOW SPEEDS By Alleyoop (Read 3,402 times)

[Alleyoop]

Yes us better oil or grease WD40 will just loosen it up for a bit and is not a good lubricate. The reason the bell gets so hot just revving it on the stand is because the pads are slipping on the bell that is what creates a lot of heat.
Alleyoop

[damorg5623]

Ok Alley, Thanks for the come back. I'll post again tomorrow, after I lube up those pivot points again and test her out, hopefully with positive results.

[Alleyoop]

The only other possible solution is find a performance Clutch that has more pad material on the pads. I have the NCY performance Clutch on mine and you can see the difference on the amount of pad that is on each parm. More pad on the arm MORE material grab the bell less slipping.

Also WHAT COLOR are the SPRINGS that HOLD the Clutch ARMS?
Alleyoop

[damorg5623]

I can't remember what color the springs on the clutch pads were, I believe that they were just like a natural spring color. You know just a metal colored, nothing special.
I'll check tomorrow when I lube them up again, and let you know. My plan is to use some of my 90 weight heavy gear oil. Hopefully that'll do the trick, and I'll be free from this nightmare finally.
It was such a great feeling today when I first rode off after spraying the pivot points with the wd40.
The scooter started off smooth as silk with absoluetly NO shuddering what so ever. I was sure that we had finally solved this. I still think that we have, it's just as you said, the wd 40 didn't last long as a lubricantans it started to shudder again. Only this time not as bad and not as soon.
I was wondering...
Do you think that in time, with a little bit of use, the pivot points will wear a bit so that the clutch pads won't be so tight, and need another lube job in the future, or do you think that this is something that I'll have to do every now and then as needed?
I guess I'd better wait and see if this heavier oil does the trick tomorrow before I jump ahead to the future, huh?

[Alleyoop]

Yea, I have 3 sets of complete clucths and I always experiment. I swaped arms from one to the other and What I did find was that some fit tighter than others and that is why I took the pictures just in case someone had a problem like yours. Now it may also be that the Pads are a little to THICK which would make them bind on the sides and not on the stud. But that can also be fixed by Taking the Arms off and sanding down the arms where it retracts between the two pieces. Also the hole on the pad that fits the stud can be sanded down a little to swivel more freely. Since the entire clutch heats up the metal expands and can cause binding after it heats up. But all that can be fixed with a little sanding and a little grease here and there and you then can have free swivel arms that will not bind due to heat expanding the metal.
Alleyoop

[damorg5623]

OK, The springs are like I said... spring colored.
They haven't got any paint color on them at all.
I lubricated the 3 pivot points on the lutch pads again this morning (yesterday now) I used the heavy gear oil, and then I also applied some grease. A few years ago I purchased a pack of various size syringes to be used to put the gear oil in to my 150cc Roketa. I also ended up buying a pistol grip oil can, so i never used the syringes. I used the largest syringe to put the gear oil on the pivot points, and the smallest to squirt the grease in there. after I had worked the clutch pads a bit, I used a Q-tip to try and make sure that there wasn't any extra grease or oil about, that might get thrown in to the clutch bell when the thing was spinning around.
After I reassembled everything, and was ready to take my scooter for a test drive, I crossed my fingers and took off.
It took off once again, smoooth as silk. That didn't surprise me, it took off smooth as silk yesterday after I had used the WD 40. The test would come after about 30 minutes of riding.
Now, I noticed when I first started off that my rpms had to get higher this time before my scooter would move. I am afraid that I must not have gotten ALL of the extra grease and oil off of the clutch, and it is slipping. It's just a tiny bit, but it is noticable. I rode for just over an hour, stopping and starting about 2 dozen times or so, and NOT ONCE did my scooter shudder. I was able to feel/tell, that the clutch did however slip every time that I took off. I was still able to get the scooter up to 65 mph, it just took a little bit longer. My scooter use to shoot off like a rocket, except for when it would start to shudder of course.
I think that today, and the next few days will be the real test as to whether or not We have solved the shuddering problem. I plan on taking a nice long ride everyday for the next few days. The weather here in baltimore has been excellent for riding these past several days. Not to mention great for working on my scoot. Not hot at all, low humidity, nice breeze blowing, just beautiful.
Ok, I'll get back to you tomorrow hopefully with a short and sweet report, just saying that my scooter is still NOT shuddering during take offs.
I do have one question for you alleyoop...
How serious is the clutch slippage?
I could live with it a whole lot better then I could the shuddering.
I'm thinking about waiting a few days, maybe a week, and then opening up the CVT again, hopefully this would be the last time for a good while, and cleaning up the clutch pads and the clutch bell. You know, cleaning off the excess grease and oil.
Does that sound like a good plan, or do you have a better idea?

Dan

[Alleyoop]

Fantastic!! The pads were binding a little and not swiveling in and out freely. If it still comes back do what I said sand down a little on the sides of the arms where they retract so when they heat up and expand they will have a little room and not bind.

Many do not realize that with the heat the metal expands and can bind the arms if they have a tight fit when retracted and if they slip enough also causes the pads to glaze prematurely.
Good Job Dan
But at least now you know what causess the shuddering and you still have some options to do on the arms if later it starts to shudder again.
Alleyoop

[damorg5623]

Alright Now,
Here is my final post on the subject of my Shuddering/Shaking MC-54-250cc. Motor Scooter.
It turns out that ALL the shuddering was definately being caused by the drive clutch pads sticking.
After applying a heavy gear oil, and a bit of axle grease, to the 3 pivot points of the clutch pads, 3 days ago, the shuddering has NOT returned. The entire first day, EVERY take off was as smooth as silk. I was able to drive thru a parking lot, at sppeds less the 2 MPH. without a single shake or shudder. The second day, every once in a while, (maybe 3 times the ENTIRE day) the scooter would shudder when going very, very slow, less then 2 mph. It NEVER shook or shuddered on take off.
From my expirence with scooters, and I've had three, a 50cc, (2004 - 2008) a 150cc, (2008 - 2012) and now this 250cc. (2012 - ) Anyway, a little bit of shudddering is completely normal at times during take offs and when riding very slow. It would be so great if every take off, and every time a scooter went less then 2 MPH., it would react as mine did the first day after I lubed the pivot points on the clutch arms, and respond everytime smooth as silk. But they don't. A little bit of shuddering is normal.
Now, if my shudddering/shaking problem happens to return, or get worse, I WILL go ahead and remove it, then dis-asssemble the entire drive clutch assembly and sand the pivot points a bit. I am sure, with out a doubt, that would solve the shuddering/shaking problem once and for all.
Alleyoop, I couldn't have done it without you!
Thank you so very much for ALL of your feedback and insight.
Ben Butin, Thanks for leading the way, and for the postings of your shuddering problems.

Good Luck, and GOD Bless!

Dan

[Alleyoop]

That is some good news Dan, glad I was able to help.
Alleyoop

[damorg5623]

Hello Again Alleyoop,
How have you been?
I last posted back in mid-September. @ that time I thought that, WITH YOUR HELP, and that of Ben Butin, I had found what was causing my "SHUDDERING" PROBLEM.
I contacted Goldenvale and after a bit of back and forth, they sent me an entire new "Clutch Driven Assembly". If you remember, when we first tried to solve this problem, you suggested that I try lubricating the 3 clutch shoes pivot points in the Clutch Assy. When I lubricated the pivot points/pins/studs, the shaking, or shuddering would go away for several days and my scooter would take off as smooth as silk. I also had troubles riding at a slow seep, say thru a parking lot . Lubricating those pivot points solved BOTH of those problems.
My scooter would take off every time, run at very slow speeds, extremely smooooth.
That would last for about 10-14 days, or until the lubrication wore off.
I was extra careful not to use too much lubrication.
I used a syringe type oiler, and a Q-tip to remove any excess lubrication. I also lightly sanded the clutch pads, and the inside of the clutch bell, to remove any excess lubricant.
Like I said this fix would last for almost 2 weeks depending of course on how much I rode.
Anyway, this NEW CLUTCH has the same exact problems.
I received it a few days ago, and I was able, because of the GREAT weather we've had here in Baltimore the past few days, to install it yesterday.
Now, I'm wondering what the odds are that BOTH the original, and the NEW CLUTCH, are both defective, in that the pivot pins/studs are a wee bit too large.
Could the shuddering/shaking problem be caused by something else, and lubricating the pivot points only made the problem go away because it made the clutch shoes expand so easily?
Could I maybe need lighter roller weights?
Goldenvale sent me a new variator in the very beginning, but that didn't solve the problem, so I had to send it back as part of the deal for them to send me the new Clutch Assy.
Anyway Alleyoop, PLEASE try and think of what could be the problem, and what is it that is causing my shaking/shuddering problem.
I am at my wits end here!
I guess that maybe I need top take your other advice and take apart the Clutch Assy. and sand the pivot points down a bit, so that they allow the clutch pads to move more freely.
My problem is this...
How do I determine how much to sand them down?
Is there a chance that I might sand them down too much and cause another different and possibly worse problem?
Or would I have to really sand alot off before that would happen?

I respect your opinion a lot Alleyoop so...
Please advise me as to what you think would be the best way to go about solving this problem... ONCE AND FOR ALL.

[Alleyoop]

Well as you know all the CLUTCHs are from CHINA and quality is not one of their most important interests(HAHA). So you will find that the CLUTCHS are pretty much made sameo sameo and they put those suckers together by hand just as your doing. The Parts are all made from moulds and the problem is they do not clean them off nice and smooth, they just bang the metal off the edges and that is all. Now if they were sanded down and polished nice and smooth that would be a different story(HAHA).

As you found out it is the Clutch that is causeing the shuddering and usually that will always happen at very slow speeds. The only other thing that may cause that are the tranny gears slipping but you already proved that is NOT the problem.

The slipping is due to NOT ENOUGH CENTRIFIUAL force to throw out the PADS with enough force to really grab the bell good and hold the bell without slipping. So if there is any amount of binding on the SWIVEL part of the ARMS the BELL will slip on the CLUTCH PADS due to not enough pressure. Another thing you can do is rough up the inside of the bell so that the PADS have something rough to grab on. Yet another possible fix ALONG with sanding down so it does not bind is VERY LIGHT CLUTCH SPRINGs. With Very Light Clutch Springs the ARMS would get thrown out with more force at very low RPMS. I do not know what the OEM springs on that CLUTCH is rated out. So maybe you can ask the dealer about weaker springs and see if they do have weaker springs.

But I do have to say roughing up the inside of the bell will eventually not last and get smooth again over time. I believe the best solution is work on the Swivel Part of the Arms and try to find LIGHTER SPRINGS so it does not take a lot of rpms for the ARMS to be thrown out. That will allow the pads to grab the bell with very low rpms.
I do not have anything else that I can think of Bud.
Alleyoop

[damorg5623]

OK, I WILL take the original clutch apart, since it is already off of the Scooter, I WILL carefully sand, and polish the swivel points.
I have noticed a slight slippage in the clutch bell, but that is definately from the lubrication that I applied. It is really hard to get ALL of the lube off, even using A Q-tip. The only thing that the slippage seems to cause is a much slower take off.
I WILL let you know what the final outcome is.
It may take me a week or two to get the job done, because I have to decide how I'm going to get that BIG nut off. Whether I'll borrow a large socket from somone, or take it to a neighborhood corner auto shop and ask for a BIG favor?

Thanks Again Alleyoop... for everything!

Dan

[jct842]

For what it is worth a lot more scooters esp larger ones shudder when taking off from a stop light or what have you than people let on about.
I have a 400cc one. Mine shudders. I have repaired it several times only to have it start doing it again. What I did was to remove clutch bell and sand it good and evenly. Then I sanded the shoes. Lubed and it was fine for a while.

I have noticed if I do hard starts and lots of throttle it seems to hold on longer but I can't do that all the time as I live on a 2.2 mile dirt road. I have just decided to live with it as the only time it does it is when start rolling. Once it is at 5 mph it is fine.

[damorg5623]

Hello jct842,
Thanks for your input.
I went around to several local, neighborhood auto shops today trying to find one that had a 38mm socket, so that I could open up the clutch and get to the pivot points in order to sand them down a bit, so I wouldn't have to lubricate them ever again. I couldn't find one. The largest metric socket that most of them had was a 36mm. So, I looked around the internet at the auto parts stores, and I finally found a 38mm at a place called Salvo Auto Parts here in Baltimore. I took my clutch with me, thank GOD, because as it turns out the nut that secures my clutch together is 42mm. One of the places I had passed earlier in the day was a place that worked on BIG trucks. So, I thought what the heck I'll ask there. Sure enough, one of the mechanics there had the exact size that I needed. He was glad to help me out. He just loosened the nut and I went on home. Now I have the clutch ALL apart, and it seems to me that the arms are moving freely enough. What does seem to be sticking is...
There are three really small rubber(?) bushings that the arms seem to get hung up on when the release. They sit on these three little tits that are pressed in to the clutch cover. The part of the cover that also has the pivot pins pressed in to it. The clutch pad arms have a notch in the middle of them, on the side that isn't visible until you take the clutch apart. These rubber(?) bushings seem to me, to be too large or too something, because the clutch pad arms are definately getting hung up a little bit.

Hey Alleyoop, if you don't mind... As soon as you read this could you PLEASE give me your insight on these rubber bushings? You could call me on the phone if you'd like, that would make it easier to discuss this problem. I can be reached at 4436531674
If you don';t want to call, PLEASE write and tell me what you think I should do now.
I hopnestly don';t believe that sanding the pivot studs and shinning them up is going to help.
Those seem to me to be very free moving.
Thanks!
Dan

[Alleyoop]

Hi Dan,
Sorry I forgot to mention those little rubber bushings for each arm to come back and sort of lock down. And yes they do tend to hold the arms pretty good. I know because when I took some of my clutchs apart I took the springs off and it took some pressure on my part to pull the end of the arms out. I think they are there so the arms do not rattle when the arms are retracted, I see no other reason for them. Maybe you can slice a little rubber off each side to lessen the hold on the arm.

OR maybe sand around the indentation on the arm that fits the rubber bushing.

Since you got a new clutch and your messing with the old one you can experiment a little. Since the arms do come out withoug binding now that may help even more.

Alleyoop