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Scooters - Big Bore => Xciting 500 => Topic started by: HTCneil on November 07, 2010, 01:57:24 AM

Title: CVT belt replaced, something strange happened.
Post by: HTCneil on November 07, 2010, 01:57:24 AM
 I just replaced the stovk CVT belt cause it snapped on my way to galveston. (17,500 miles)

ANyways, my dealer replaced it and I have encountered these strange events:

Before it snapped, I would redline at 75 miles per hour indicated. I generally on the highway would cruise at 70 mph and it would be at 7000rpms.

NOW, with the replaced belt, Kymco belt, I redline at 82mph indicated and when i cruise ay 70mph, the tachometer says only 6500rpms


Sooooo what happened? Did it always redline at 82mph when i first got my bike, but over time when the belt loosens or gets older it increases rpms.

Another odd thing is i have lost about 2 miles per gallon, nbow only at 41mpg with the new belt. You'd think with the reduced rpms i would get better gas mileage.

Help 500ri experts!
Title: Re: CVT belt replaced, something strange happened.
Post by: axy on November 07, 2010, 12:35:41 PM
I just replaced the stovk CVT belt cause it snapped on my way to galveston. (17,500 miles)

ANyways, my dealer replaced it and I have encountered these strange events:

Before it snapped, I would redline at 75 miles per hour indicated. I generally on the highway would cruise at 70 mph and it would be at 7000rpms.

NOW, with the replaced belt, Kymco belt, I redline at 82mph indicated and when i cruise ay 70mph, the tachometer says only 6500rpms


Sooooo what happened? Did it always redline at 82mph when i first got my bike, but over time when the belt loosens or gets older it increases rpms.

Another odd thing is i have lost about 2 miles per gallon, nbow only at 41mpg with the new belt. You'd think with the reduced rpms i would get better gas mileage.

Help 500ri experts!

The dealer has installed a longer belt than OEM belt.
Longer belt = higher revs
It is a paradox, most people would think that longer belt = lower revs.

You need more revs to achieve the same speed.

Your acceleration could be a bit better, because with longer belt, you have shortened the effective gear ratio.

The consumption could rise a bit (insignificantly probably).

Certainy, this is much better option than having a shorter belt that could snap.
Title: Re: CVT belt replaced, something strange happened.
Post by: Hoolander2 on November 07, 2010, 04:30:27 PM
Axy, look at his figures again -- his revs went down, not up!  Maybe the dealer cleaned and greased his torque driver for one thing. 

For another, maybe he left the washer out of the variator.   ;D  Which would be fine, . . . we think.
Title: Re: CVT belt replaced, something strange happened.
Post by: Hoolander2 on November 07, 2010, 04:32:47 PM
By the way, HTCneil, your revs are now more like the rest of us, I do believe. 
Title: Re: CVT belt replaced, something strange happened.
Post by: axy on November 07, 2010, 07:28:35 PM
Axy, look at his figures again -- his revs went down, not up!  Maybe the dealer cleaned and greased his torque driver for one thing. 

For another, maybe he left the washer out of the variator.   ;D  Which would be fine, . . . we think.

You are right.
Everything I wrote is still correct though (in reverse).
I would check the belt length. It would not be the first time they install shorter belt by mistake and these things tend to snap.
Ask MarioG for details... he had too short belt on his Agility, now he has also a new variator and he was lucky for not having bent crankshaft too when the belt snapped.
Title: Re: CVT belt replaced, something strange happened.
Post by: scootergrisen on November 08, 2010, 12:48:36 AM
The old belt was worn to the means it is not so wide and that mean it cant push the variator plate aside as much as a new belt.
I have also changed my belt some time ago a that also increased the topspeed because the old belt was 1,2 mm smaller in width then the new one.
Old belt : 16,35 mm wide.
New belt : 17,57 mm wide.
And they where both the type type of belt.
Here is some pictures : http://scootergrisen.dk/scooterhjemmeside/service_transmission.php (http://scootergrisen.dk/scooterhjemmeside/service_transmission.php)
Title: Re: CVT belt replaced, something strange happened.
Post by: axy on November 08, 2010, 10:15:09 AM
The old belt was worn to the means it is not so wide and that mean it cant push the variator plate aside as much as a new belt.
I have also changed my belt some time ago a that also increased the topspeed because the old belt was 1,2 mm smaller in width then the new one.
Old belt : 16,35 mm wide.
New belt : 17,57 mm wide.
And they where both the type type of belt.
Here is some pictures : http://scootergrisen.dk/scooterhjemmeside/service_transmission.php (http://scootergrisen.dk/scooterhjemmeside/service_transmission.php)

Wow! This is what I call proper documentation! :) :) :)
Btw. I guess that Danish rigtigt means the same as german richtig or correct?
The picture on the right shows correct placement of roller weights?
Title: Re: CVT belt replaced, something strange happened.
Post by: ts1 on November 08, 2010, 03:30:25 PM
I too just changed my Xcitings belt and sliders at 25'km.
As expected, the rpm decreases. Still can't definitely compare the new mileage (dithers too much).

rigtig (dk) = richtig (de).
Title: Re: CVT belt replaced, something strange happened.
Post by: axy on November 08, 2010, 04:15:56 PM
I too just changed my Xcitings belt and sliders at 25'km.
As expected, the rpm decreases. Still can't definitely compare the new mileage (dithers too much).

rigtig (dk) = richtig (de).

For how many kms did the last belt turn around? :)
The same question for the rollers.
Title: Re: CVT belt replaced, something strange happened.
Post by: ts1 on November 08, 2010, 04:23:19 PM
Both 25'km. Finally they rubbed off below their safe tolerance. I dislike certain surprises and took no risk.
Title: Re: CVT belt replaced, something strange happened.
Post by: axy on November 08, 2010, 09:55:26 PM
Both 25'km. Finally they rubbed off below their safe tolerance. I dislike certain surprises and took no risk.

Wow!
I was thinking the belt would be below specs sooner than that, like 12K kms or so, as for 125 cc machines...
Title: Re: CVT belt replaced, something strange happened.
Post by: HTCneil on November 09, 2010, 08:44:14 PM
So what you all are saying is, I am back where i needed to be in regards to the rpms per mph.

So its safe to say, that over time maybe my redline will decrease as the belt gets worn?

Then why the reduction in Miles per gallon. 3 miles per galloon is significant. I aint getting no better than a Harley at 40-41mpg.?????
Title: Re: CVT belt replaced, something strange happened.
Post by: scootergrisen on November 13, 2010, 11:54:55 PM
Quote
rigtig (dk) = richtig (de).
Das ich richtig  ;D Seer gut.

I dont know what you only go 41 mpg. Maby the belt just needs to be used a little... but have you changed the rollers also ?
Check your tirepressure and pump to the right pressure.

And then ask some one with the same scooter as you have and ask how maby mpg they ride.

Title: Re: CVT belt replaced, something strange happened.
Post by: axy on November 14, 2010, 04:57:54 PM
So what you all are saying is, I am back where i needed to be in regards to the rpms per mph.


To be honest, after 12 years on scoots, I have never noticed revs going up or down after belt replacements.
However, I have noticed, and only on 50 cc 2strokes, that they accelerate maybe a tad faster and have a bit higher top speed after new belt is installed.
For 125 and 250... nothing.
Title: Re: CVT belt replaced, something strange happened.
Post by: Hoolander2 on November 23, 2010, 03:16:36 AM
Hey, HTCneil.  I just replaced my belt too and got the same symptoms as you.  I think the reason the gas mileage went down is, with the lower revs, I was having to twist the throttle more to get the same acceleration I used to get.  I'm guessing that on a long highway trip we'd see the mileage go up nicely, though. 

I wound up putting my old belt back on cause it seemed to ride smoother with it.  I'll leave it that way till I tune my clutch a little with some stiffer springs.  Then try new belt again. 
Title: Re: CVT belt replaced, something strange happened.
Post by: EFIALTIS on December 21, 2010, 02:38:04 AM
Try to install MALOSSI belt, and check the nut and washer if they install correctly
Title: Re: CVT belt replaced, something strange happened.
Post by: HTCneil on January 31, 2011, 06:06:30 AM
still only getting 37-39mpg
Title: Re: CVT belt replaced, something strange happened.
Post by: HTCneil on January 31, 2011, 06:07:25 AM
Try to install MALOSSI belt, and check the nut and washer if they install correctly

how do i check that?
Title: Re: CVT belt replaced, something strange happened.
Post by: Hoolander2 on January 31, 2011, 04:43:31 PM
Unfortunately, you'd have to take the variator off to see if dealer installed the washers correctly.  It can be quite a job if it's your first time and you need a tool to hold the variator plus a big breaker bar or impact wrench.  You could take it back to the dealer and report your symptoms --see if they'll agree to take it apart and inspect their work.  It's possible they didn't reassemble it right. Of course, try to be respectful in approaching the subject so they don't get the feeling you're accusing them of doing anything wrong.   

There are 3 washers associated with the variator.  2 of them must be put in in exactly the right way.

Inner washer has a "step" which must face the crank case.  Middle one must be between the two halves of the pulley and must not be confused with the outer washer. 

One thing you could do which is simple is take off the CVT cover and look to see if they installed a Kymco belt or some other replacement belt.  Kymco belt has cogs on both inner and outer surfaces and has KYMCO written on it. 
Title: Re: CVT belt replaced, something strange happened.
Post by: htcneil2 on January 31, 2011, 05:27:16 PM
hoolander or sprok3et,

do ya'll have pictures or a diagram?
Title: Re: CVT belt replaced, something strange happened.
Post by: spr0k3t on January 31, 2011, 11:28:19 PM
I'll check when I get home.
Title: Re: CVT belt replaced, something strange happened.
Post by: spr0k3t on February 01, 2011, 03:45:52 AM
Found it.  I tell you, I love having that service manual around.  Just let me know if you need finer detail of a certain area.

(don't mind the lack of Microsoft or Apple in that screenshot, I use what I like).
Title: Re: CVT belt replaced, something strange happened.
Post by: Hoolander2 on February 01, 2011, 04:05:56 AM
Hey Htcneil2.  I sent you an email on how to view my service manual pages online with me.  I guess you didn't see it in time -- I put it up for 25 minutes or so.  Can try again sometime if you want to set up a time, I can let you look through it while I'm online.  Something new I'm trying through Adobe kind of like computer sharing online.  Shares my screen with people I invite. 

Hey, spr0k3t, I don't know how to do a screenshot!  Ha!  How do you do that? 
Title: Re: CVT belt replaced, something strange happened.
Post by: Hoolander2 on February 01, 2011, 04:16:25 AM
Ok, I see you're online again Htcneil2 so I'm putting it up again for 20 min.  Click the link in the latest email I sent you.
Title: Re: CVT belt replaced, something strange happened.
Post by: spr0k3t on February 01, 2011, 04:36:27 AM
Hey, spr0k3t, I don't know how to do a screenshot!  Ha!  How do you do that?

Well, on Ubuntu, I just hit the Prt/Sc button and a requestor pops up asking for details of how I want the screenshot saved and cropping methods.  Then I make any edits needed using Gimp.  How to take a screenshot in windows or mac... no clue.
Title: Re: CVT belt replaced, something strange happened.
Post by: spr0k3t on February 01, 2011, 04:46:45 AM
Found a good detail pic of one of the primary washers that is specific to the side it is connected to.  This should help.