|
Post by scooter7878 on Sept 23, 2021 22:50:11 GMT -5
The rollers weight difference is going to vary depending on a lot of variables. So in a scoot let's say u have a stock contra spring in clutch and 7 gram weight seems the best. Now same scoot u install a 1500 contra spring and keep the 7 gram weight. The rear clutch with the stiffer contra is harder to spread so the shift is gonna happen later keeping a higher rpm bc the weights are same but the rear pulley is taking more force to open so there is a lot of things that will affect the weight of the rollers. The weight of the bike,and of the rider ,the stiffness of the contra ,the angle of the secondary slider sheave slots and if there straight or dual angle,the variator ramp angles, possibly the diameter of the variator and the clutch if they are different,how much tourqe the engine makes and probably a ton more other variables. There's a lot to tuning the cvt a lot of trial and error so many small difference in things can affect things in big ways. U would be amazed at the difference that one gram in weight can make. I was running 6 g ideas and running 0 to 40 in 13 sec. I switched to 7 g sliders and went to 0 to 40 in between 8 and 9 seconds. I was amazed at the difference one gram made. U gotta play with each set up till ur happy. I'm not sure if that answered what u were trying to find out but that was what I could come up with
|
|
|
Post by GrumpyUnk on Sept 24, 2021 10:49:46 GMT -5
Only thing I can add to the above is that having a tachometer is an absolute necessity if you are going to tune. The tach rpm reading will indicate if the engine is spinning above or below the torque curve. In general, the rpm should climb quickly to a set, and the speed increase to catch up the the rpm. If the rpms are too high, you are past the torque peak, and will accelerate slower, too low, and you are below said peak, and the same results. I will guess and say torque peak is around 7k-ish. Any that know, speak up as I only have one machine right now that is working and has tach. IT seems ok, but has not had anything done besides put oil in the sump and fuel in the tank. It is the dual-shock that was broken... tom
|
|
|
Post by andy670ho on Sept 24, 2021 19:20:32 GMT -5
The rollers weight difference is going to vary depending on a lot of variables. So in a scoot let's say u have a stock contra spring in clutch and 7 gram weight seems the best. Now same scoot u install a 1500 contra spring and keep the 7 gram weight. The rear clutch with the stiffer contra is harder to spread so the shift is gonna happen later keeping a higher rpm bc the weights are same but the rear pulley is taking more force to open so there is a lot of things that will affect the weight of the rollers. The weight of the bike,and of the rider ,the stiffness of the contra ,the angle of the secondary slider sheave slots and if there straight or dual angle,the variator ramp angles, possibly the diameter of the variator and the clutch if they are different,how much tourqe the engine makes and probably a ton more other variables. There's a lot to tuning the cvt a lot of trial and error so many small difference in things can affect things in big ways. U would be amazed at the difference that one gram in weight can make. I was running 6 g ideas and running 0 to 40 in 13 sec. I switched to 7 g sliders and went to 0 to 40 in between 8 and 9 seconds. I was amazed at the difference one gram made. U gotta play with each set up till ur happy. I'm not sure if that answered what u were trying to find out but that was what I could come up with Put some 5 gram rollers in from the Kymco and this thing really took off! I can’t believe they had 8 gram in there. How much do pod filters help? How about a little better exhaust?
|
|
|
Post by scooter7878 on Sept 24, 2021 23:26:45 GMT -5
The rollers weight difference is going to vary depending on a lot of variables. So in a scoot let's say u have a stock contra spring in clutch and 7 gram weight seems the best. Now same scoot u install a 1500 contra spring and keep the 7 gram weight. The rear clutch with the stiffer contra is harder to spread so the shift is gonna happen later keeping a higher rpm bc the weights are same but the rear pulley is taking more force to open so there is a lot of things that will affect the weight of the rollers. The weight of the bike,and of the rider ,the stiffness of the contra ,the angle of the secondary slider sheave slots and if there straight or dual angle,the variator ramp angles, possibly the diameter of the variator and the clutch if they are different,how much tourqe the engine makes and probably a ton more other variables. There's a lot to tuning the cvt a lot of trial and error so many small difference in things can affect things in big ways. U would be amazed at the difference that one gram in weight can make. I was running 6 g ideas and running 0 to 40 in 13 sec. I switched to 7 g sliders and went to 0 to 40 in between 8 and 9 seconds. I was amazed at the difference one gram made. U gotta play with each set up till ur happy. I'm not sure if that answered what u were trying to find out but that was what I could come up with Put some 5 gram rollers in from the Kymco and this thing really took off! I can’t believe they had 8 gram in there. How much do pod filters help? How about a little better exhaust? . Yes rollers make a huge difference sliders are better as I said from 6 g to 7 g made a 3 sec difference in 0 to 40 times. Also the big spring behind clutch a 1000 or 1500 rpm spring helps greatly on hills and also it causes a faster down shift so when u let off gas from higher speeds it goes into a lower gear faster so u don't get that lag of acceleration from a high speed decel to hard throttle again. The uni filter is the only pod to use that and a exhaust with a bigger jet will get u a decent gain in power but may require a spring and roller weight adjustment as it will shift ur power band to a higher rpm get sliders though they last way longer and shift smoother and better
|
|
|
Post by scooter7878 on Sept 24, 2021 23:30:18 GMT -5
If u upgrade to exhaust and uni pod go up at least sizes main if not more and get a 1000 rpm contra spring and yellow small clutch springs and either 5 or 6 g Dr pulley sliders. If u get 5 and 6 g sliders u will have a a range bc u can mix 3 5g and 3 6g in staggered to get in-between 5 and 6 grams
|
|
|
Post by scooter7878 on Sept 25, 2021 0:02:13 GMT -5
Only thing I can add to the above is that having a tachometer is an absolute necessity if you are going to tune. The tach rpm reading will indicate if the engine is spinning above or below the torque curve. In general, the rpm should climb quickly to a set, and the speed increase to catch up the the rpm. If the rpms are too high, you are past the torque peak, and will accelerate slower, too low, and you are below said peak, and the same results. I will guess and say torque peak is around 7k-ish. Any that know, speak up as I only have one machine right now that is working and has tach. IT seems ok, but has not had anything done besides put oil in the sump and fuel in the tank. It is the dual-shock that was broken... tom forget to mention one of the most important things lol. A rpm gauge is a must bc my but Dyno told me 6 g was better than 7g sliders but I did timed runs and from 6 to 7 g sliders was more than a 3 second difference. Sometimes the engine reving higher tricks u into thinking it's faster but timed runs proved it was not
|
|
|
Post by andy670ho on Sept 30, 2021 16:40:14 GMT -5
Only thing I can add to the above is that having a tachometer is an absolute necessity if you are going to tune. The tach rpm reading will indicate if the engine is spinning above or below the torque curve. In general, the rpm should climb quickly to a set, and the speed increase to catch up the the rpm. If the rpms are too high, you are past the torque peak, and will accelerate slower, too low, and you are below said peak, and the same results. I will guess and say torque peak is around 7k-ish. Any that know, speak up as I only have one machine right now that is working and has tach. IT seems ok, but has not had anything done besides put oil in the sump and fuel in the tank. It is the dual-shock that was broken... tom forget to mention one of the most important things lol. A rpm gauge is a must bc my but Dyno told me 6 g was better than 7g sliders but I did timed runs and from 6 to 7 g sliders was more than a 3 second difference. Sometimes the engine reving higher tricks u into thinking it's faster but timed runs proved it was not Getting this thing better, it takes off awesome, rpm comes up and pulls hard but at about 10-15 the rpms drop it seems too much as it starts to shift. How can I keep my shift rpm up just a little? I have a 1000 and 1500 contra spring sitting here along with some 1000 rpm small springs for the clutch. I do have some shims coming for the variator as the belt is sitting up when at the idle position, bringing it down a ways in the rear clutch. Any help is appreciated!
|
|
|
Post by GrumpyUnk on Oct 1, 2021 8:12:14 GMT -5
Lighter variator slider weights? The variator works against the contra spring pressure, and if the weights are 'heavy' the variator will squeeze the belt out quicker, getting to higher gear.(dropping rpm) You have to have a balance between the contra spring and variator rollers/sliders. Someone that tunes can explain better. tom
|
|
|
Post by andy670ho on Oct 1, 2021 12:58:59 GMT -5
Lighter variator slider weights? The variator works against the contra spring pressure, and if the weights are 'heavy' the variator will squeeze the belt out quicker, getting to higher gear.(dropping rpm) You have to have a balance between the contra spring and variator rollers/sliders. Someone that tunes can explain better. tom Went with 6 gram sliders and it completely cleaned up the rpm drop on the shift, waiting for the tach to come in but thinking 7 or 8 gram sliders might be better. It is very revy now but acceleration is way better than the 5 gram rollers. It gets up to 35-38 pretty fast then climbs to 40ish. My Kymco Agility 50 is now way slower than this one, need to get that one up to speed, the Lifan has a bigger Carb on it, wondering if that’s the difference?
|
|
|
Post by scooter7878 on Oct 1, 2021 13:46:30 GMT -5
There's such a balance that has to be achieved and everything is different for every bike and rider small changes can make a big difference. My 0 to 40 times with 7 g sliders are 3 second faster than 5 6 or 8 sliders. That's a big difference from 1 g weight. The ideal weight is the one that when u pin throttle from a stop the rpm's climb to whatever that engine power band is and stays at that rpm till u get close to too speed. Mine is about 7800 most are between 7 and 8500 depending on mods. A rpm gauge and gps speed is important bc u thought I was going faster with the 6 g sliders but sometimes just the higher reving tricks u into thinking ur going faster both rpm and gps speed is a must for the best tuning they don't lie so u know 100 percent what is best
|
|
|
Post by scooter7878 on Oct 1, 2021 13:48:09 GMT -5
The yellow contra spring makes a big difference for me my clutch blew a while back and I slapped on a whole clutch assembly I had laying around with a stock spring and when I went back to my regular set up with the yellow man what a difference in power
|
|
|
Post by andy670ho on Oct 7, 2021 18:38:52 GMT -5
The yellow contra spring makes a big difference for me my clutch blew a while back and I slapped on a whole clutch assembly I had laying around with a stock spring and when I went back to my regular set up with the yellow man what a difference in power So I’ve made this bike go much better but it seems to not go much faster then 40-41 on a flat run. What am I missing for a little more speed?
|
|
|
Post by scooter7878 on Oct 7, 2021 23:34:48 GMT -5
I'm not sure what upgrades u have but a stock 50cc does around 35. With some small upgrades u can get about 40 or a little more. If u want more than that u need to up gear but in order to push the up gear u need a big bore kit the stock 50cc can't push the taller gears no matter what u have done without a bigger cylinder and head unfortunately ur pretty much topped out at what u got without a cylinder. U might squeeze 45 from it but that's pushing it. U can get a 50mm cylinder and piston and a big valve head and a intake u will be closer to 45 to 47. I got my 139qmb 50cc doing 62 mph and 0to 40 mph in 9 seconds but I dropped some bucks. Stroker crank,50mm high compression piston,bvh, naraku variator there's really nothing more but nitrous I can do. U can get to 50 to 54 mph with a cylinder, exhaust,bvh,cam,and a few other things and not to to expensive once u start trying to crest over 54 or so it gets expensive.
|
|
|
Post by scooter7878 on Oct 7, 2021 23:35:37 GMT -5
What engine is it a qmb?
|
|