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Discussion Starter · #1 ·
YP400 Majesty 2006, 40K miles : Have just had a reputable shop replace rear tire and V-belt, and all was fine for ~ 100 miles. A few days ago spent 30 minutes in hot traffic jam creeping along, stopped to re-fuel, and then found that I had lost significant power (~ 45 MPH full throttle, very slow acceleration). I pumped out the fuel tank and refueled with know good fuel. No unusual noise or resistance. Spark plug, oil and filters are all looking fine. Engine starts great. I understand the it might be a fuel pump filter clog, but not sure where to access that. Any suggestions?
 

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Hi Frank, Welcome to the forum.

The first thing to check is the speedo drive which is located in the front wheel, It will break if not greased properly.
The net likely problem area is the throttle body diaphragm, this is located on top of the motor just where the air intake and fuel lines intersect. You will have to remove most of the body plastic to get to it. I would preorder a new one as the dealers usually don't stock them.
Let us know what you find.
Tony in Tn 06 Majesty with 72k on the clock
 

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So what did the problem turn out to be ? And what was the fix? Did it just overheat?
 

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Discussion Starter · #5 ·
The word I got was that there where flat spots on the CVT rollers - although they say they inspected them prior to installing the new V belt, and said they where fine. The assertion was the that perhaps the new belt "did in" the old rollers during that first few hours of operation. This adds ~ $300 to the existing work of changing the belt and rear tire 3 weeks ago.

Has anyone experienced "quick roller failure"? Or is it more likely that something happened to the rollers when the V-belt was replaced?

Thanks for your replies to date! This is the first serious issue with the Majesty in 11 years of ownership....can't complain!
 

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If you didn't see the rollers taken out of YOUR Majesty, I would be suspect of the repair shop. Yeah that sounds ugly but I have seen many things like that in my life. The rollers were fine and 100 miles later they are bad? The new belt did in the rollers? If you know how the belt and rollers relate to each other, you would know how ridiculous that sounds. I smell BS. Either they were already bad and they lied about checking them, or something else happened and they are trying to cover it up. Or the rollers did really go bad in 100 miles, after being fine for 40K miles and X number of years. Something ain't right with all that.
 

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Frank, your problem sounds like a faulty fuel injector diaphragm, as Tony mentioned. When mine developed a small hole, the symptoms were exactly as you described.
 

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Discussion Starter · #8 ·
It looks like faulty fuel injector diaphragm may be the issue.....replaced rollers only had minor improvement on situation. Thank you Jim and Tony for suggestion.
Will keep things posted on outcome.
 

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If you click on the "How To" page, you'll find a thread called "Replace the throttle diaphragm." That will be helpful, if you do it yourself. I added a few tips further into the thread. It's not hard to do, really, but a lot of plastic has to be removed, which is tedious, time consuming, and will run up the labor charge at a repair shop.
 
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