Post by 90GTVert on Jul 12, 2009 22:18:59 GMT -5
O.K., so our CVT transmissions don't shift like a multiple gear transmission, but the torque driver should "shift" to let the pulley open all the way to obtain a higher effective gearing. Mine has decided not to shift for me anymore.
I don't have a tach installed, but I can usually go 50MPH at a moderate RPM and the engine doesn't start revving near it's max till somewhere over 55MPH. It's probably a pretty subtle difference, but I cruise at those speeds so much that the difference in sound is obvious to me. Last night my engine started winding out before I was even to 50MPH and I was topping out at around 52MPH. I took it for another ride this morning and it did the same thing.
I pulled the CVT apart and checked roller wear, belt condition, made sure the contra spring was intact, and that the rear pulley moved freely. I took it for another ride and it did the same thing.
I have the clutch assembly from a 139QMB here, so I took a look at it out of curiousity. It looked like the pulley and torque driver were pretty much the same. Everything fit up well, but the splines on the bell were different. I swapped the minarelli clutch on the GY6 pulley using the GY6 contra spring.
Bell size and spline difference. Left :139QMB Right : Minarelli
Left : Minarelli pulley/Minarelli contra spring/139QMB clutch
Right : 139QMB pulley/139QMB contra spring/Minarelli clutch
I installed the hybrid clutch assembly onto it's shaft and then installed the bell. I noticed that the bell and clutch were stuck together, so I pulled it back off. It turns out that the threads on the 139QMB torque driver are too long to work with the minarelli parts causing the clutch bell to sieze against it.
So much for that idea.
I decided to take the torque driver apart to see if anything was amiss. I never saw a problem, but I did clean and grease everything while I was in there. I'll post a how-to in the tech section at some point for anyone interested.
EDIT : Here's the how-to.
I took it for another ride. I pulled out of my driveway and accelerated to about 50MPH and then it shifted, and shifted hard. There was a jolt as it changed positions and the RPM dropped. I went up the road a little and turned around. It never felt like a shift this time, but it would get to 55MPH revving high. I tried a few more times with similar results. It's close to normal, but just not quite there now.
I don't have a tach installed, but I can usually go 50MPH at a moderate RPM and the engine doesn't start revving near it's max till somewhere over 55MPH. It's probably a pretty subtle difference, but I cruise at those speeds so much that the difference in sound is obvious to me. Last night my engine started winding out before I was even to 50MPH and I was topping out at around 52MPH. I took it for another ride this morning and it did the same thing.
I pulled the CVT apart and checked roller wear, belt condition, made sure the contra spring was intact, and that the rear pulley moved freely. I took it for another ride and it did the same thing.
I have the clutch assembly from a 139QMB here, so I took a look at it out of curiousity. It looked like the pulley and torque driver were pretty much the same. Everything fit up well, but the splines on the bell were different. I swapped the minarelli clutch on the GY6 pulley using the GY6 contra spring.
Bell size and spline difference. Left :139QMB Right : Minarelli
Left : Minarelli pulley/Minarelli contra spring/139QMB clutch
Right : 139QMB pulley/139QMB contra spring/Minarelli clutch
I installed the hybrid clutch assembly onto it's shaft and then installed the bell. I noticed that the bell and clutch were stuck together, so I pulled it back off. It turns out that the threads on the 139QMB torque driver are too long to work with the minarelli parts causing the clutch bell to sieze against it.
So much for that idea.
I decided to take the torque driver apart to see if anything was amiss. I never saw a problem, but I did clean and grease everything while I was in there. I'll post a how-to in the tech section at some point for anyone interested.
EDIT : Here's the how-to.
I took it for another ride. I pulled out of my driveway and accelerated to about 50MPH and then it shifted, and shifted hard. There was a jolt as it changed positions and the RPM dropped. I went up the road a little and turned around. It never felt like a shift this time, but it would get to 55MPH revving high. I tried a few more times with similar results. It's close to normal, but just not quite there now.
