Triton # 2 (T2) 49cc to 110cc & Nearly Everywhere In Between

[90GTVert]

Jul 24, 2018 10:46:56 GMT -5 lordverminaard said:

I'm still baffled that you need weights that high. I'm using a Koso vari made for a Jog 90, so it's slightly oversized compared to a stock one and a koso yellow spring. I have 4g sliders and they are still too heavy. I noticed a big difference in how your variator acts compared to mine when you were off-throttle after reaching higher speeds, almost immediately after my RPM's start dropping, my rear pulley will start closing steadily until all the way closed, which acts a lot like an engine brake, so much that I don't need to use the brakes much when just needing to slow down and it seemed like yours wanted to coast in top gear for quite a while before the pulley started closing.

I also have a stock clutch, lightened, and with generic "yellow" springs in them as well, and I notice that it doesn't hit nearly as hard as I want it too but it does fully engage before the variator starts doing it's thing. I feel like putting any softer springs on it would make it drag too much.

Do you have a stock spring and roller set kicking around? I'd install those just for funsies and see if it's way worse or if it does anything better.

These are sorta light weights to me. With most of my other setups that use the PG pipe I'm 10-12g with the same contra that I had in there. These aren't super stiff contra springs either. Heck, I was using 7-8g with the 70cc sport kit. I tried weights that came with the OR kit IIRC and it hit something like 14-15,000RPM once when I got my first OR on T1 with a 103cc and a Peace Pipe.

I looked back at some info from the 232 0-40 runs that I did ~5 years ago within a month or so with a 70cc to test various variators, rear pulleys, and belts. I was using 4-5g weights with a stiffer contra in the stock CVT. Nearly everything else used 7-8g. That's a 70cc with less torque than this has.

Prob also helps to keep in mind that the OR is designed for high revs. I know one site says it's for use with engines that rev 12,000+RPM. Many people have also told me that I can't use an OR with my low rev engines.

[90GTVert]

Rain, rain, rain. Not a good day for test runs, but the voltmeter that 190mech linked to a month ago came in today. $1.20 shipped and it took 1 day short of a month to arrive.




I thought about putting silicone in to seal it, but it looks like it would be tough to seal from all sides so I just left it as-is.




I made a bracket out of some thin aluminum that used to be a SSD tray. May have to use something more substantial if it doesn't hold up. Luckily it's a large display so I can see it easily enough even low mounted. I was initially going to just use clips for the battery terminals, but thought it wouldn't be a bad thing to have more permanently so I wired it in properly for key on operation.






Checked vs meter.

[190mech]

Glad you got one!Been running that same unit for 4+ years in a couple of cropdusters(for testing only),lens gets faded in sunlight,but is still easy to read..Nice to know voltage in a glance...

[ryan_ott]

I picked up a few of those also mine came late last week. I also find it strange how long it takes for your cvt to “down shift”. I tend to run a stronger spring because I like to pull out of corners strong. Building motors is quick compared to the tuning. There are always improvements to be made.

[90GTVert]

It cleared up long enough for the roads to dry, so I took it down the road. Top speed, 52MPH. Too much RPM as expected. It didn't have such a vibration, but RPM is up too. Haven't even taken the cam off of the scoot to see what the belt is doing. I'll need heavier weights to know if a useful tune with the stiffer contra is better.

Hopped off the scoot and it started raining again.


The NCY stator is pathetic. Headlight on, right at the end of the driveway, it's 12.4V. Headlight off about 12.7-12.8. That's with pulling it off of the charger minutes prior. By the time I got home from a 7 mile test run, with the headlight off 3/4 of the time, 12.2-12.3V or 12.5-12.6V. I think I saw the gauge go up 0.1V once when I got on the gas. Pretty much like the stationary testing already told me, the NCY stator just barely puts out anything with the ground floated. The voltmeter definitely lets me know I better not intend to count on the headlight for long with it like this. I'll be sensible and go back to the stock stator sooner or later. Luckily days are still long ATM.

[repherence2]

Jul 24, 2018 14:20:58 GMT -5 90GTVert said:

Jul 24, 2018 10:46:56 GMT -5 lordverminaard said:

90GTVert that video of the CVT was interesting.  the first thing that I thought of when I saw that belt was contra spring, being too light for the amount of weights in the variator.  have you ever read Arnadanoob's  CVT tuning strategy on hondaspree?   his strategy is heavier weights, heavier spring. 

per Arnadanoob,

"Hey 808, I think it's fine, just need to match the weights to that center spring and no, you don't have to have someone follow you around for belt slap, if the belt is that bad you'll notice it when it's on the center stand and rev it with slight rear brake load. 6:9 is rather tall but good overall, 1000 center is around 39-42g at the front pulley usually, depending on quality of center spring and rider weight. If you have problems coming out of corners where you feel it's not downshifting enough, then upgrade to 1500 and start with 42g and tune upwards on the weights to your preference. Lighter guys can go with 45-48g with 1500 center while the heavier guys can go with 42-45g. I know of some guys that go 48g (8g x 6) and like it... but it all depends on the pipe they use too.

There's 2 tuning approaches with a trans...

- heavier weights, stronger center spring
- lighter weights, softer center spring

I prefer to go with lighter weights and softer center spring since it's less taxing on the belt. Each method has its ups and downs.

The softer center spring combo is nice for casual riding or riding that involves a lot of longer distances since the the softer spring combo will want to keep a higher gear easier than one using a stiffer center. The weakness of the softer combo is that if you go from a very high speed into a very low speed corner and try to accelerate hard, the softer center spring will tend to be a little lazy with pushing the rear pulley halves together to give you that really low gear to punch hard out of corners. The softer spring combo is ideal for riding that allows you to carry speed through it without much slowing down.

Then you have the heavier weight combo which uses a stronger center spring, usually a 1500 for a ZX trans. This combo will tend to have higher belt tension in general and the belt will not be drawn into the rear pulley as easily, making your front pulley and weights work more. This setup tends to be friendly for those hard accelerating runs (not so much holding 1 solid speed) since the stronger center spring is more willing to push the rear pulley halves together to provide you a much lower gear faster. If you want to do more cat and mouse type of riding around areas where riding speed ranges differ a lot, this is your setup to go with. If you do a lot of long distance cruising, the trans will want to downshift faster so it's a little more effort on the part of the motor to maintain a higher gear (because the higher spring tension wants to downshift)."

I know it pertains to Dio's but that's the same CVT strategy that I go by.  the Jogs seem to use lighter weights than the Dio's as far as my reading and understanding.  I know having a stock clutch must be making the CVT tuning more challenging.  there's only so much you can do with a stock clutch with heavy springs.  life changed when I bought a Stage 6 Torque Control clutch.  the adjustability of it in regards to clutch spring installation and pre load tension is fabulous.  I don't really understand the art behind the little brass weights that you can insert into each shoe, but the ease of changing out springs and adjusting pre load to get the desired engagement RPM is wonderful.  by the way, the last 3 clutches that I ran were DIO clutches (Polini Evo 2 shoe, Malossi Fly, Stage 6) but I am also using a Polini Evo clutch bell 107mm.

I apologize if what I did by quoting Arnadanoob from the other site is against the rules.  by all means delete/edit this post if it does violate the forum rules.  I just didn't want to paraphrase his words and details get lost in translation, so I thought to quote him. 

[90GTVert]

I've never read any of that. My CVT tuning methods have been from 10+ years of playing with them a lot. Long ago, I kept hearing about stiff contra springs. Gotta use 'em. Tried them. Didn't get it. Tried stiff contra springs back to back with light contra springs. As far as heavy weights, heavy spring and light weights, light spring... that's not a strategy IMO. That's physics. 10+ years ago, before this forum was created, stepthrutuner (then rallyrrr) said he liked the term "contra spring" more than main spring, torque spring, etc... because it portrays that the spring contrasts the weights. That's why you normally see me call them contra springs to this day, because I agree with that. If you use a stiffer spring, RPM will increase unless you increase weight. If you use a softer spring, RPM will decrease unless you reduce weight. That's just how it goes. IMO if it's in tune, as far as keeping the RPM you want, you can't really say this or that is too heavy for the other thing. They have to be right for each other or you can't get the RPM that you're looking for.

What I often do is stick with springs on the softer side unless proven necessary to go with a stiffer contra spring. As I eluded to earlier, at one point I tested heavy springs with heavy weights and light springs with light weights and I couldn't tell the difference. I did it back to back so I'd really notice if anything changed much. I couldn't tell. My thought is that the contra spring gets more credit than it deserves sometimes. The variator is working regardless of spring weight; with the exception of going so light on roller weight that it can't do anything or when you limit it with rollers too light to act against the force of the contra spring to get full travel. Also, the contra spring gets all the credit for stopping belt slip, but it's a joint effort as I see it. Heavy rollers don't so directly and obviously squeeze the belt like a contra spring, but are they not exerting a greater force upon it? If they're heavier, they should move outward with more force than lighter rollers. If they are moving outward with more force, along the ramps, that action is working to close the variator, which squeezes the belt. So thinking about it that way, it seems like all credit can't go to the contra spring. It all goes back to the whole idea of contrasting or counteracting forces.

Since I could never get an obvious result from stiff contra springs, it has seemed pointless to me to use a really stiff spring that is harder to work with. If all else is equal, you'll hate that stiff spring when you break down and try to change a belt on the side of the road. Most of the time belt strands end up in the rear pulley with these kevlar belts and it's hard enough to try and get them out on the road as-is. There's also the argument that some say a stiff contra spring stresses the belt more and could even reduce output. I've never worried too much about that one and I think someone with a dyno would need to figure the output part out.

So pretty much if my belt isn't slipping or slack, I don't tend to move up in contra spring stiffness. I adjust roller weight to get the RPM I'm after. Could be that I'm all wrong, but I've spent a lot of time on the CVT of these scooters over the years and it's gonna be hard to convince me that what I've been doing doesn't work since it has for me. This is not theory or reading or watching anyone else. This is from who knows how many test and tune runs.


There is likely some advantage in contra springs in that they can be designed to have a different curve. Not how they bend, but pressure difference within usable travel. From putting them on a scale on the drill press, I've seen that some springs can have a really similar pressure at installed height (rear pulley closed as it would be for low speed). Then they can have totally different pressures from one another at compressed height (rear pulley open as it would be for high speed). For example, I had 3 springs that I measured within 2 pounds of each other at installed height. They were 71, 72, and 73lb. At compressed height, they were 93, 116, and 126 pounds according to me and my scale. So I had a 73/93, 71/116, and 72/126. Over 30lbs difference in compressed pressure with 3 that you might as well call the same at installed pressure. I would have to think that has an effect on RPM/shifting as speed increases, where the stiffer ones should be holding RPM slightly higher than the softer ones as they open more. If that's enough to notice easily, can't tell you. Probably depends exactly what you're tuning and how picky/precise you are.


Regarding the clutch; if it goes off the line then I don't know that I really have to have a fancy clutch. Pretty much my only complaint ATM is that I have that vibration. Damn rain has kept up for days so I haven't messed with it much to see if the contra does anything. I still think it's a mismatch issue somewhere. Remember, I had it exactly how I wanted it very briefly, and then of course my old steel OR pulley had to blow itself apart and ruin that. It's just now with the aluminum pulley that it doesn't want to act the same.

[90GTVert]

The rain quit today, so I got to work on T2 a little. I started out with 10.25g sliders, up from 9.75g. Top speed still 52MPH. I changed to 11.5g sliders. Top speed up to 54MPH. The heaviest I had was 12g, so I made up 3 aluminum fillers for a set of 10g weights to take them to 14g. Mixed those with 11g to average 12.5g. That got speed up to 55MPH, so still low. The problem is, with it setup like that it's starting get low in RPM and feel softer at times. Still does well taking off, but it seems the contra spring is just too much for it to overcome with reasonable weights on the top end.

It's actually easier to take off easy now, but that's because it's not so snappy. If I wanted to dull it down, I would have already put a sensible flywheel and stator that charges back on it. It will still go hard from a stop, but from a roll there's more of a delay and then a hard pull. For example, instead of jerking the front up; it would start revving and then pull it up. With lighter weights it was still snappy, but then I'm nearly 10MPH slow.

I didn't notice the bad vibes. There are still vibes, but not like the one area that I got with the softer spring. It seems like the stiff spring and heavy weights do control the belt better as expected. Not sure what good that does me since I want to use more of the variator. Could be just differences in RPM/speed/pulley position. Maybe a slight change in weight could get the old setup working better. It's not like a spent a whole lot of time on choosing weights for it.


One option would be a spring with similar installed pressure, but less compressed pressure. That's easier said than done though. As I said in a previous post, I have a bunch of springs and half don't even fit the OR how they should and none of them fit that bill. I'm not really interested in a wild goose chase for the perfect spring (after who knows how much more money in additional springs).


Here's a video of it to compare to the one with the softer spring so you can see for yourself. Maybe I'm just dense and I can't see what everyone else does with these stiff springs, but to me it looks real similar to the softer spring... just with lower speed. I put "Slow Acceleration" at the beginning of the vid. To clarify, that was me accelerating without a lot of throttle to slowly move through speeds.

[pitobread]

Change moving sheath ramp pins to other angle and try those?

[90GTVert]

I have tried those, just not with this spring. With the other spring, these grooves work better. Could change with the spring, but I wasn't anticipating a 5MPH gain from that. I may try it just for the sake of science. Not totally sure if I will do that or just go back to the other spring.

[Lucass2T]

I keep looking at this thread and keep thinking how you can have so many problems with the CVT and getting it tuned right? Boggles my mind. Especially with the consistency you keep and still haven't been able to get it right. Have you tried just for the f#ck of it swapping to totally stock CVT parts and see how it does that way? Dunno, maybe that'll give another insight on the situation.

[90GTVert]

To me it really comes down to the rear pulley. I know long drawn out stuff is a pain to keep up with, so let me make a quick summary.

-Everything was great with the steel pulley, till it came apart.
-I try to use the aluminum pulley and suddenly it acts different.
-After a little work for more clearance it improved. I still think there was some lack of effort in the aluminum pulley's design.
-Then my main complaint was that vibration which looks like it was the belt tension at a specific point based on what the first CVT observation vid on the previous page shows.

That's really not that bad. Most of the aggravated fiddling with the CVT from earlier in the thread was because of the big carb and intake and I just wasn't sure if it was the clutch and CVT.

When I did take the long ride with the newer setup, to be fair to it that was not at all extensive CVT tuning. I tried 2 or 3 weights, called it close enough, and rode it. Performed well and consistently all day, with again the complaint being the vibration at low speeds. Now a secondary complaint is belt life. Not enjoying seeing .75mm gone in 300ish miles, but it may just be what happens when you put 300 pounds on a scooter and try to make it go hard.

Oh, and the reason I have totally not put anything near stock on is because I don't care how it works. I don't mean that as any sort of insult to anyone suggesting it. I'm saying I've tested stock and OR back to back and the OR does wonderful things for performance. I'll have a whole new set of headaches with the Peace Pipe and a stock CVT and it will never do what it does now. Even with a HOCA rear pulley and a HOCA variator with mods, when I had a Peace Pipe on my first high rev 103cc I had to hit 12,000RPM to get max speed. Switched to the OR and suddenly it could stay around 10,500 and response was more immediate. This thing really isn't going to pull that high. Pipe is pretty much the same, but I didn't go crazy on durations this time.

[90GTVert]

I'm starting to loathe this thing. Put back the old spring, 10g weights. Decided to cut the face of the variator down so I could make more slack for the belt with hopefully just as much squeeze for the high end. Worked in mock up. In practice, didn't do a whole lot. Top speed about 60MPH. Pretty much normal. I stuck another OR vari on. Little worse takeoff than the modified one, similar top end. I think there's just a certain amount of travel that's willing to happen on the drive boss. Taking material off the the center makes it have to travel more to get to max travel. Thought maybe that would be OK with the longer grooves in the torque driver, but it's like I've hit a wall.




Maybe a softer torque spring would do it. From having 11g in before, it does travel more with heavy weights, but they have to be heavy enough that it's a compromise. Never felt like I had quite so much compromise with the old steel pulley. As I've said, that's what is really irritating me. I wish it were possible to get a no BS answer about the engineering of this thing, to know if it was mostly marketing to sell a higher dollar pretty part that doesn't have crappy welds with little concern of not using the whole grooves like the steel pulley used to... or if there were some actual engineering reason like maybe this thing is an improvement if you have 30HP and rev to the moon. I know that's not even in the realm of possibility though, because if there's any truth in the former it would be awful for business. I don't claim to know what's the truth. I'm merely interested for educational purposes.

At any rate, I can see from just changing weights around that there may be some merit to a stiff contra for control, but the vibration is not always as severe... depending where it happens related to weights.

For now I've got a brand new belt in there, because I'm starting to not trust the "old" one. Not using a spacer in the var either. Not taking off as hard, but judging by the way it has gone, it won't be that long before it's worn down and taking off harder again.

If money were no object, I'd pick up another steel pulley and a couple more new belts and not worry about it. Not quite that lucky. I may have to do the belts before too long if I ride much.



In addition to that crap, the weather is horrible. The dew point has been following the temperature closely so it's really wet air. My rich tune does not like that. I tried moving to a 98 main from 100 and W4 from W3. The W4 is exactly the same as a W3, but 2mm shorter taper. That small change put it from blubbering if I stick around part throttle to smoothing out, but spark knocking. I think that likely means I'm way rich there with the W3, but my timing is probably a little high so the richness is necessary. For now, I've stuck with the 98 main, but went back to the W3.

It may be that I've got a plug fouling though. One day I had a hard time starting it. The last couple of rides it has ran awful at first. It sputters and blubbers and doesn't want to go... but then I get some heat in it and it runs alright. After a little distance I can go WOT and it will slowly come around till it's clean. May still break up a little under heavy load, like during a shift in the CVT (that shouldn't be there, but that goes back to this aluminum pulley I guess) or occasional quick WOT after slower riding. I suppose all of the fouling could be telling me I should try a heat range up, but I still run it hard on long stretches and I feel safer with the BR8HS that I normally use.



EDIT : Oh yeah, and just to pile one more thing on; my rear tire is down to wear indicators already. Can't be that many miles on this thing. I have even told myself no burnouts so I don't wear everything out so fast. Still big chunks of noisy tread on the outsides, just worn down in the center. Sad to see the TMAX tire next to it with no chicken strips and then this thing new with the little nubs still on the outer inch. I'm sticking with it for now. Not unusable, just way more worn than I think it should be. May consider street tires again for max grip and perhaps getting rid of the whine whenever I bite the bullet.

[90GTVert]

Just checked. 924 miles on this build and the tire. I did so many burnouts on the last tire that I never really thought about it. Not impressive for such big blocky tread and a J (62MPH) rating.

[oldgeek]

Tuning woes. I am having the same problems. The high humidity here has been a nightmare for me too. Likewise my current tune sputters here and there but is better when it thoroughly warms up. Stop and go traffic on the strip gives me time to try and dial in the low speed circuit, and I dont know how many times in the last few days I have pulled over to move a needle clip. Gonna start carrying a different needle to swap in I guess Lol!

I also started this rebuild with a Polini HS variator, aluminum drive face and a longer boss. I have moved back to the other aftermarket variator, shortest boss and stock drive face.

I sat down today to try and figure out something about the variator and belt on this Kymco. I put the weights in the variator, installed the ramp plate an shook it in my hand. I could hear the weights rattle a bit, which in theory has to rob you of some variator travel. I did some minor grinding here and there to get the ramp plate to sit as low as possible in the variator, no more rattling weights. I took a spare crank I had laying around, installed the variator, boss, sliders and drive face then tightened it all up. I looped the belt over the boss to see how it fit as I held the belt tight. With the longer boss it was way too loose. I ended up using the shortest boss and the belt was still just a tad looser than I wanted. I figure any looser than necessary and it HAS to rob some of the top end because some of the variator travel is being wasted. I am experiencing a small amount of slip occasionally, but this belt is worn about .4mm Also I am back to the softest contra spring I have. As you have pretty much proven, a stiff spring is not necessary in most cases.

I dont know if the above will work with the Mina stuff, but it may be worth a try. It always bothered me adding shims testing, removing shims testing.............