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Discussion Starter · #1 ·
My belt is slipping when I am accelerating at speed. From start there are no issues, but after 80kmh (~50mph) if quickly roll the throttle, RPM might drop and then the bike picks up again, and from time to time RPM might drop again. If I roll the throttle slower, there is no issue.

The probable cause that I think of, is the CVT spring being too soft and belt is pushed into rear sliding sheave too quickly.

Thinking of 2 solutions:
  • Reducing the weight of the rollers, may be to 16 grams (17 grams stock)
  • Making the CVT spring around 10% harder

Does anyone else observe the issue? Any known solution?
 

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Discussion Starter · #2 ·
A quick update. After self inspection, what I did:

1. Replaced rollers to lighter once. I thought belt was slipping, as original 17G rollers were too heavy. I have installed 15G rollers, acceleration much better. But after 80, CVT still slipping.

Now I have realized its probably the clutch. I have ordered aftermarket clutch cover, will replace and update.

15G rollers are too light, not fun at all, after 80 its not fun, engine revs high without strong pool. I will mix 17 and 15g
 

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Discussion Starter · #4 · (Edited)
Sorted out the issue with slipping CVT.

My reason was: the larger diameter of rear tire. The bike had Pirelli Diablo 150/70-14 installed. Original Size was 140/70-14.
The tire is slightly taller and heavier, but was enough to make issues with CVT after around 2000KM. Scooter now is at 11,000KM.

The spring was too soft and belt was just pushing through and slipping. Changing spring to a harder one (just around 10% more) sorted out everything.
Now RPM are too high (around 6,500 at 100KMH) as I previously also replaced 3 rollers to 15G (Original are 17G).

Later, when changing the rear tire I will install the original size (probably will use UT or Maxxis) and put the original rollers back in.
 
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