Post by littlered50 on Apr 22, 2009 15:44:45 GMT -5
So, a couple of months back I replaced my CVT weights with Dr Pulley sliding weights.
At the same time I also replaced the slides on the backing plate, thinking that the Dr Pulley slides ought to be better than the original no-name Chinese sliders. And they where included in the pack together with the weights I bought so I thought "Why not?"
About a week ago, I started to hear what I can only describe as grinding, metal-on-metal noises from the front part of my engine, up where the front CVT pulley is located. Since I have made pretty heavy modifications to my CVT (see scootdawg.proboards.com/index.cgi?action=display&board=discussion&thread=20361&page=1) and I run a 72cc with a HP cam I thought I had killed some bearings with all my mods.
After having dark thoughts about having to replace all bearings in the engine, and starting to look for a replacement engine while I was at it I decided to pull the CVT apart and check it just to make sure. Who knows, I might be lucky...
When I tore it all down and opened up the variator, these fell out:
They where the leftovers of what had been the 3 sliders guiding the backing plate... I did not find the other bits, they must have been blown out of the CVT (I hope, or they are stuck in the clutch somewhere...).
The lack of sliders had caused the backing plate to grind away several millimeters worth of material from the guide rails inside the variator, causing the grinding noise.
Here's a pic with the new guides installed, you can clearly see where the steel backing plate has ground away material on the aluminum guide rails:
After installing the new sliders I did a few trial runs and the grinding noise is gone, much to my relief.
The CVT seems to be a bit reluctant shifting into high gear though and it is also a lot more noisier, a sort of rattling sound. Most likely because the guide rails no longer are smooth and uniform.
If you hear grinding noises from the CVT it could possibly be caused by the sliders having been damaged as above.
I am planning to fix the reluctant shifting with a new variator kit I just ordered from Autotech355, possibly I'll get some more speed out of it too since it has a different ramp angle and length.
/Otto
At the same time I also replaced the slides on the backing plate, thinking that the Dr Pulley slides ought to be better than the original no-name Chinese sliders. And they where included in the pack together with the weights I bought so I thought "Why not?"
About a week ago, I started to hear what I can only describe as grinding, metal-on-metal noises from the front part of my engine, up where the front CVT pulley is located. Since I have made pretty heavy modifications to my CVT (see scootdawg.proboards.com/index.cgi?action=display&board=discussion&thread=20361&page=1) and I run a 72cc with a HP cam I thought I had killed some bearings with all my mods.
After having dark thoughts about having to replace all bearings in the engine, and starting to look for a replacement engine while I was at it I decided to pull the CVT apart and check it just to make sure. Who knows, I might be lucky...
When I tore it all down and opened up the variator, these fell out:
They where the leftovers of what had been the 3 sliders guiding the backing plate... I did not find the other bits, they must have been blown out of the CVT (I hope, or they are stuck in the clutch somewhere...).
The lack of sliders had caused the backing plate to grind away several millimeters worth of material from the guide rails inside the variator, causing the grinding noise.
Here's a pic with the new guides installed, you can clearly see where the steel backing plate has ground away material on the aluminum guide rails:
After installing the new sliders I did a few trial runs and the grinding noise is gone, much to my relief.
The CVT seems to be a bit reluctant shifting into high gear though and it is also a lot more noisier, a sort of rattling sound. Most likely because the guide rails no longer are smooth and uniform.
If you hear grinding noises from the CVT it could possibly be caused by the sliders having been damaged as above.
I am planning to fix the reluctant shifting with a new variator kit I just ordered from Autotech355, possibly I'll get some more speed out of it too since it has a different ramp angle and length.
/Otto
