. By rosiemoto (Read 11,486 times)

[rosiemoto]

Oh okay so I won't worry about the weights anymore. Would you say the 115mm fan is the better one to use since it climbed higher? Even though the 108mm revs higher at top speed? Or do they kinda equal out do you think?

[Alleyoop]

I think they both rev the same, with the tachs you cannot tell 100 rpm differences and any change in temp and wind from one minute to another will give you different numbers so go with the one you like best. If you want little more rpms out of either one get 1/2 gram lighter weights, 1/2 gram up or down on weights does change things.
Alleyoop

[rosiemoto]

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.

[rosiemoto]

(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.)

[jaxrhapsody]

Jun 20, 2016 20:13:53 GMT -6 rosiemoto said:

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.)

Sweet, you do that. I want as less work as possible, when I eventually do mine.

[rosiemoto]

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!?

[jct842]

It takes a given amount of power to take you and your scooter up to 58mph.

I think the various pulley arrangements are just compensating differently to come up to the same amount of power. To go faster there needs to be more power available.

A while back I saw a formula that I can't quote, that gave a rate of power increase To speed increase, and it does not increase proportionally. Like 10% more power might only be 4 or 5% more speed. And the faster you are going the less 10% power gets you in speed.

[crwford]

question why can't you get 93 octane? Go to auto parts store and get octane booster at a small shot glass at a time till you get it better just don't go nuts with it. I use in in my trikes all the time they really love it.

[rosiemoto]

Alright I drilled about 15 holes around the clutch on the CVT cover, it kinda looks nice actually! I'll find out tomorrow if that helps with heat (should!).

I went back to stock variator and stock rollers (13g) and the belt refuses to return to the top of the clutch pulley at idle. It used to be right up at the very top when it was ALL stock, so I'm thinking this is likely that 115mm variator fan I put in; it seems to have a different ramp angle or something, and lowers RPM by 500 all across the speed range including top speed.

By the way: K&S variator with 13g rollers gave me almost identical results as Koso variator with 11.5g sliders. I'll be trying K&S + 13g again with my stock 108mm fan instead of the 115mm fan.

I'm thinking the problem lately is possibly I've been getting *too much* increased gearing from a bigger variator AND variator fan, and my engine isn't making it past 6,500rpm at top speed. If I understand right, you want the bike to accelerate WOT at max torque (6100-6500rpm?), then eventually top out at or not too far above max horsepower (7500rpm). This is for the GY6 4-stroke.. so adjust accordingly for your type of engine. With the weird 115mm variator fan I've been using, my engine isn't able to get past 6,500rpm at top speed so maybe that's why the loss of power around 45+mph I've been getting! I guess that added with the belt wear... something like that, still trying to pinpoint it out!

[rosiemoto]

Jun 22, 2016 17:41:58 GMT -6 crwford said:

question why can't you get 93 octane? Go to auto parts store and get octane booster at a small shot glass at a time till you get it better just don't go nuts with it. I use in in my trikes all the time they really love it.

It's that I can't get 93 in ethanol-free form around here. Actually there IS one shop that does 87-93 ethanol-free, but I was told because their gas tanks are above ground in the open, it can collect condensation, and that was told to me after I apparently had water in my float bowl after using that shop's gas faithfully for months. There's a Sunoco that sells the 90 that I've been using, and my bike seems to be happy. My bike hates gas with ethanol in it regardless of the octane, for some reason.

[crwford]

OK then put what ever fuel you use and add octane boost little at a time and check it each time to see if it helps. I use it all the time and it helps me really well.

[rosiemoto]

I know I said I'd hold off on my testing until my new belt, but I've been out there hard at work drilling CVT vent holes and swapping variators and fans, and well I've got some more results to share! I FINALLY got this thing back up to 60mph. This is with the same loose/thinned out belt as the last recent results I posted, so as usual, think of these results as all relative to each other, and not absolute numbers.

As always, the clutch etc is all stock; I only change variator, variator fan, and roller/slider weights.

Stock variator (13g rollers) + 115mm variator fan
Top speed: 52mph @ 7200rpm (ha...ha...)
RPMs: WOT 6300rpm, cruise @ 40mph 5900rpm, 30mph @ 4800rpm
Gearing "runs out" around 40mph, and rpms climb fast.

K&S variator (13g rollers) + 108mm variator fan (smaller, fins stick out past pulley)
Top speed: 60mph @ 7000rpm
RPMs: WOT 6700rpm, cruise @ 40mph 6100rpm, 30mph @ 5000rpm
Gearing "runs out" around 52+mph? I can't really tell.

Next post: CVT cover temperature results after drilling holes to vent CVT!

[rosiemoto]

So I drilled a pattern of 3/4 inch holes in my CVT cover at the clutch area yesterday, because I can't even touch my hand to it after a ride without it burning me. I don't yet have a picture to show, but here's how everything went, in order.

1: Stock CVT cover: Too hot to touch (hot potato)
2: Took CVT intake rubber piece off: No difference
3: Put intake rubber piece back on then drilled ~15 holes around clutch: Strangely, still no difference
4: Took intake rubber piece off: NOW I can touch the cover! Variator area is warm, middle and clutch areas are still a bit hot but I can at least hold my hand on it for 2 seconds.
5: Went for a gentle ride, felt it, and went for a hard ride and felt it: both were the same temperature as above (#4)

So it seems the holes only benefited when it had more air intake. Maybe I need to make more or bigger holes? Anyway, I'm hoping this will let my belts last a "sane" amount of time. I've been through 3 belts in the past 7 months, two of which were "Gates" brand that everyone seems to speak highly of. Honestly? The chinese belt I have in right now lasted the longest out of them.

[cyborg]

Lots of cheap gates copies I've heard,,,Alleyoop raved about bando

[cyborg]

Good idea about the vent holes,,,those cvt's get ungodly hot,,,even after a short run I couldn't put my hand on my vespa,,,,so much wasted energy,,I was working on a thought about putting a derailure style drive chain setup like a bicycle,,,,it would make any scooter seriously fast,,,but the cost was crazy,,,and I sold the bike instead and went to a 4 speed manual scoot