Hello there JR.
My name is Dan & I'm one of the the guys with the shuddering MC-54-250
As I understand it, there are several out there.
Just to get this out of the way, This is an almost brand new "2011" scooter.
I purchased it this year, back in July.
It does have the big rubber center stand stop/bumper attached, so that is not my problem.
I called Goldenvale/Roketa months ago asking about this shuddering problem, and the first thing they did was send me a new variator.
That turned out not to be the problem.
Then by posting on scooterdoc.com I was given some other suggestions on how to solve the shuddering and shaking problem.
I tried lubricating the clutch arm, pivot studs with some heavy gear oil, using a syringe oiler.
This did, as I posted solve the problem for several days.
My scooter took off from a stop as smooth as silk. I was also able to ride slowly thru a parking lot at speeds of less the 5 mph.
Before I lubed the clutch arm pivot pins, my scooter would have shuddered like crazy.
It was real embarassing when people would see how much my scooter would be shuddering.
Goldenvale/Roketa then sent me a new clutch assembly, I had to return the Variator, but this new clutch does the same thing, just not as bad.
The funny thing is that later on in the day that I installed this new clutch, I was supposed to go to my grandsons soccer game.
Because I was afraid that this new clutch might not solve the problem, I lubed it's pivot studs before I installed it.
Just like my original clutch, this new clutch took off as smooth as silk. The soccer game was about 25 miles away, so a round trip was about 50 miles.
Just as I was pulling up to my house, on my return trip home, this new clutch started to screw up.
However, the problem is a little bit different.
For a lack of a better way to express it, I will say it like this...
When I take off now, it's like I have a real motorcycle clutch and when the rpm's get to a certain speed, the transmission SLAMS in to gear.
It also shudders a bit, but no where near as bad as the original one did.
Now, I did notice the belt size, and it was different then what i had expected it to be.
The belt that is on my MC-54-250 says that it is a size 918 x 22.5
I sent an e-mail to Goldenvale/Roketa and asked them about this, and I was told that it was correct.
The reason that I questioned this is...
If you go on to the Roketa.com web site, and look up the MC-54-250 parts breakdown it doesn't show a picture of my belt, in the exploded view of the engine parts, nor does it list it in the parts breakdown list.
They do however list the belt for the MC-54B-250 and it is a different size then mine.
Anyway, It was suggested to me that if I were to sand down and shine the clutch arm pivot studs, that most likely would solve my shuddering problem once and for all.
I took the original clutch apart, since it was already off of the Scooter, to do that and I noticed that there are 3 little rubber rollers that the clutch arms lock on to when the clutch is idling, and I'm wondering if they are the problem. The clutch arms seem to really get hung up tight. I've sent some picture of this clutch and it's associated parts, including the little rubber rollers, to goldenvale/Roketa for their help.
I'm hoping that whoever built these clutches back in China put the wrong size little rubber roller on them.
They seem to measure (using a metric ruler) 11mm across.
Also, I noticed that there are 2 dings, it looks like they were made with a special tool. I'm guessing to balance my clutch assembly, they are in the clutch face plate.
There are also 2 dings in the clutch bell, I'm guessing for the same reason.
I've seen pictures of other clutches and they don't seem to have these dings.
Anyway, I'm currently awaiting a response from Goldenvale about the rubber rollers, and the dings.
If you have any other suggestions, I would greatly appreciate the help.
I am so tired of trying to figure this problem out.
I'm glad that winter is coming, that way I won't feel so bad when I see others happily riding down the road.
Thanks for your time and for any help you can give.
Dan
I tried to attach pictures of my disassembled clutch, I don't know if it worked.
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