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I have to pause my testing for now, and possibly redo that last test - It seems no matter what I do, I'm always capped at 58mph, and the same struggle from 50 up to top speed. So I decided to measure my belt as it was looking kinda thin, and there's so much belt dust everywhere, and yep it's slightly under 19mm already! I just replaced it a few months ago and it began at slightly over 20mm! Last night I spent some hours trying to figure out why I'm going through belts so quick. Here's why I think: my CVT case gets VERY hot after a ride, even when I ride it gently. You can't EVEN touch the case for a half second, it's that hot. I had no idea there's supposedly an air filter in the front of it; I thought it was just simply holes, so I'm going to give that a look today and clean that out as it's NEVER been in in 15,000 miles! Possibly remove it if it continues to get hot. If there's NOT an air filter in there, then I'm looking into drilling holes in the back where the clutch is, to vent. I've read many posts and clutch area is where a lot of people have very good results.

On another note I believe I've improved my takeoff power in the most simple way - I cleaned my clutch bell with soap+water, rinsed, then rubbing alcohol'd the area where the clutch pads grab onto the inside, got it "squeaky clean". Then I scrubbed the clutch pads with a paper towel to get the belt dust, dirt, etc off, then alcohol'd them too (no soap or water). After all was done, I eventually gave it half throttle at a stoplight for the fun of it, and wow I didn't expect it to pull that hard from a stop. For the first time I was actually wondering if I went WOT if it would've popped a wheelie!?

(NOTE/edit: this test may be invalid; I'm having CVT heat issues, and my belts are "thinning" too quickly... looking into it! But I'll leave this post here for now)

Here's my results from going from 12g sliders to 11.5g sliders. In a nutshell: Low speed acceleration (0-30mph) is the same. Acceleration at midrange speed (30-45) was improved (I felt more pull). Top speed dropped 1mph, and high speed acceleration (50mph+) seemed more sluggish.

SETUP:
- Koso variator
- 11.5g Dr Pulley sliders (3x 11 + 3x 12)
- 115mm variator fan (generic)
- Stock clutch stuff (generic clutch bought from eBay)
- Stock chinese belt 842-20-30 ($9)

RPM behavior: When WOT, rpm stays at 6,100 after clutch grabs, then around 30mph RPM starts climbing to 6,500 and stays, then at 45 slowly goes up again and hits 7,000 at top speed (57mph). So, RPMs from 30mph up to top speed are 500 higher than the 12g.

Throttle response: feels nicer during acceleration, but worse when cruising. Cruising feels like you're in 3rd gear instead of 4th, and needs more throttle to keep the bike up to speed. I found I was going 38mph instead of 43 with the same amount of throttle I normally cruise at. Everything about 50mph felt lacking. On the other hand, acceleration was noticeably improved in midrange speeds.

---A note about Koso: After reading a review, I now understand with a stock setup, the Koso variator may/will cause the belt to ride lower in the clutch pulley at idle/takeoff, which is like taking off in 2nd gear. This may not be a huge deal unless riding 2up like I commonly do, or if you're a 250lbs+ rider.

Final ratings (out of 5 stars):
- *****: Takeoff acceleration (0-10mph @ 4,000 rpm)
- *****: Low speed acceleration (10-30mph)
- ***** Medium speed acceleration (30-45mph)
- ***** High speed acceleration (45mph+)
- ***** Top speed (57mph)

Next test: Same setup, but swapping to K&S variator + 13g rollers (yes ROLLERS next time, not sliders!)

(Eventually I'm going to compile ALL my testing info neatly in one spot like I did some pages ago, and stick it on my first post to make it easy for those interested to see and keep up with. I'll keep updating it as I do more experiments.)

This has been happening for a while and didn't seem to be too bad, but this morning I came out to a big dried up circle of oil on the ground, and I actually had to top up my engine oil a little (was down to 1/4 on the dipstick)! The "puddle" was located straight below the airbox, and I think the oil on the ground may be coming from that little clear/yellow vent hose that dangles from the airbox (the bottom airbox hose; see pic). Every hose that comes out of the airbox is saturated with oil where it meets. Messing with their hose clamps seemed to temporarily stop the oil leaking out from the hoses before, but now it's just like it's "overflowing" from the airbox. I have the engine oil filled up to the center of the dipstick.

It won't leak to the ground right after a ride; it only does it behind my back when it's been sitting.

Also maybe related - this morning the bike was HARD to start and took a lot of cranking with some throttle. Until today it has been starting perfect since I did my valve adjustment about a month ago. Seems it doesn't want to start cold? Once it was warmed up it would restart no problem like nothing ever happened. Did the valve adjustment pop loose?? But what's with all this oil...

This picture is from it being parked for 1 hour after a ride. I'll add more in a new post when/if I can get more:

Yeah Cyborg, I think it has that play. I definitely get it when doing the front brake.

Do I have the procedure right in this picture?

Hobbles,

Thanks for the pictures! Mine seems to be a little different than yours and the one I saw on YouTube by Rolling Wrench. I'm not sure how to proceed... I don't have any wrenches that big. A video said use a spanner wrench, but I don't know the first thing about those, what size to get, etc.





I'm assuming I'd loosen the top nut, then tighten that huge white one, then tighten the top nut back to it?

Oh, is there just 1 nut for the front end then?? For some reason the way he did it made me think there was 2 different nuts, but then I wasn't looking!

On the scraping, so far it's been while 2-up, and we both notice it while going slow in a parking lot. I haven't ridden solo since it started, but will do. It doesn't seem to be affected by engine RPM (happens with engine off too!). I didn't notice it at road speed at all... only scrapes in parking lot. I tried rocking the bike and jumping on the bike to bounce it, and I didn't hear any weird sounds there.

I forgot to mention, I tried manually spinning the rear wheel with bike on center stand, and it sounded normal. 

I'm back, and got some more tuning info and experimenting yet to do! I know some of you wanted me to chill out on all the tuning and just enjoy the ride, which I did for a little while, but I can't help it! Well, it's really because even with the valve adjustment and A/F mixture, I'm still stuck at 57-58mph indicated top speed, and it takes quite a while to get up to it. I feel my bike is running good, but not to its full potential. My goal is to get it back up to 61mph like I was getting when I first started all this.

So, first thing I've got for you all is, regular 87 gas (+10% ethanol) was a big no-no in my bike; I lost power to the point I was beginning to think something was wrong with my bike. Also my RPMs were noticeably lower; unable to reach 6k rpm anymore. I didn't hear any pinging or strange engine sounds though. I have just gone back to 90 ethanol-free gas and still on my first tank, so I'll be back with results, but so far can already say "much better" vs the regular 87 gas. I've concluded my bike runs best on non-ethanol gas, even after the valve adjustment etc, and whenever I put gas with ethanol in, I lose the linear throttle response and it feels like I'm riding uphill.

If with this 90 non-ethanol gas my bike is still stuck at this stubborn 58mph top speed, I'm going to do more variator/roller/slider tuning. If this happens (I think it will), my next experiment is going to be swapping to lighter sliders, by mixing 11s and 12s. The reason for that is, my RPMs may be a little too low (and below powerband) to reach top speed, so hopefully top speed and acceleration would both be improved.

Current setup:
Variator: Koso 115mm
Variator fan: 115mm
Roller weights: 6x Dr Pulley 12g sliders
Belt: Cheap chinese 842-20-30 belt
--Top speed: 58mph @ 6500 RPM
--Cruise speed 40mph: 5,200 RPM
--Acceleration WOT from a stop: 6100-6300 RPM

Since I'm using the 115mm variator FAN now (previously 108mm), I'm getting different results (RPM all around lower by 200-400) and I'm thinking the setups that were too light in my previous tests, may work good now.