Here is a quick write up on how I installed the Dr. Pulley OD weights.  All of this was done on a 2014 Zforce 800ex.  Im not sure what translates over to other machines but I will keep it as general as possible and more about the weights install than the machine.

You need to take the cover off of your CVT to access your primary pulley.  Put one of the shorter bolts from the CVT cover in the driven pulley threaded hole to give some belt slack.  You then take the nut off the primary pulley to remove it from the engine.  Remove the entire assembly from the engine/trans and the rest of the work will be done outside of the machine.  Remove the cam plate and sliders.  Then you can remove your stock roller weights.  Mine had some flat spots in them that were causing the clutching to hang up and not perform the same every time i accelerated.  Make sure the tracks in the sheave/pulley are smooth and dont have any groves.  It is best to clean them out with air/paper towel and maybe some mild cleaner if there is anything hanging on in there.  Now you can install your new Dr. Pulley OD (Over Drive) weights.  They will go with the tall flat side against the inside of the sheave/pulley with the short side facing the outer portion and the round part down.  Once all the OD weights are in place put the cam plate back in place along with the cam plate sliders very carefully.  You should now be holding the sheave/pulley with your thumb on one side holding the cam plate and your fingers on the sheave face so the weights do not slide/move/come out of place.  From this point on you DO NOT want to let go of the of this grip until I tell you different.  Put this assembly back into place on the machine (DO NOT LET GO YET!!!) and roll the assembly back and forth to make sure that you have the splines lined up and started from the shaft to the cam plate (STILL DO NOT LET GO YET!!!).  Start the nut on the cam place once the splines are started(STILL DONT LET GO YET!!!) and tighten the nut down all the way. NOW YOU CAN LET GO!!!  I stress this be 99.999% of the time people put OD weights in they do not hold firm pressure all the way through the process and one of the weights falls over or comes out of place.  This causes the machine to preform HORRIBLE and everyone asks questions about "Why is it doing so bad?".  If you take your time and hold the cam plate and sheave together you will be able to do it.  At this point reassembly is per normal.  Torque the nut and install the CVT cover and whatever else you did to get in there.

My mini review of them is as follows - I did notice better low end pull and slightly more top end on mine (i stayed with the same weight sliders so they are only different in shape).  Also as my sliders were damaged the shift out and back problem was fixed and I have not noticed any inconsistencies in its shifting.  The OD weights are pricey at $80 vs normal rollers but if you are looking for slightly better clutch performance than there is no other alternative.  I wanted to try slightly lighter weights but they were unavailable at the time so I may swap out for lighter ones down the road and report back after that.  Sorry no pictures this time as I was in a hurry.  The whole process on my Zfoce 800ex took 35 min to do so its not to bad of a job.

This is good info. Where did you get the weights? This may have been covered already somewhere else, if so I apologize. I've been looking around for some but haven't had much luck. Thank you.

[2015 Z Force 800 53/Trail EPS]

This is good info. Where did you get the weights? This may have been covered already somewhere else, if so I apologize. I've been looking around for some but haven't had much luck. Thank you.

ebay

Stock is 30X18 25g. you can search for 30x18 and just pick the weight you want

Sweet thanks. This is good info. I want more low end grunt and a weight change was one of the things I'm looking at.

Update: I think the weights have "settled in" a bit more.  By this I mean I believe that the weights have worn smoother on their contact surfaces that they touch the sheave.  They seem to be sliding easier and better.  Not that it was ever bad...just better than at first. 

At this point i dont really need anymore low end as I dont run big tires (only 26") and I dont play in the mud.  So for me it just spins the tires on command which is great.

Dont expect it to be like buying a 1000cc machine because it just isnt that much of a difference.  It is however better at shifting the power.  I would like to try different weights but I am by no means unhappy with what I got.  I may try some lighter ones at some point but im in so hurry.

I ride tight trails with a little bit of mud and some steep hill climbs. I have 8ply 27's. I want to go to B2 setting. Should I go to 24gr sliders

[2015 Z Force 800 53/Trail EPS]

I ride tight trails with a little bit of mud and some steep hill climbs. I have 8ply 27's. I want to go to B2 setting. Should I go to 24gr sliders

Depends on what you ride and at what altitude. Put what you have in your signature then tell us where you ride and what extra weight you carry.

Here is a quick write up on how I installed the Dr. Pulley OD weights.  All of this was done on a 2014 Zforce 800ex.  Im not sure what translates over to other machines but I will keep it as general as possible and more about the weights install than the machine.

You need to take the cover off of your CVT to access your primary pulley.  Put one of the shorter bolts from the CVT cover in the driven pulley threaded hole to give some belt slack.  You then take the nut off the primary pulley to remove it from the engine.  Remove the entire assembly from the engine/trans and the rest of the work will be done outside of the machine.  Remove the cam plate and sliders.  Then you can remove your stock roller weights.  Mine had some flat spots in them that were causing the clutching to hang up and not perform the same every time i accelerated.  Make sure the tracks in the sheave/pulley are smooth and dont have any groves.  It is best to clean them out with air/paper towel and maybe some mild cleaner if there is anything hanging on in there.  Now you can install your new Dr. Pulley OD (Over Drive) weights.  They will go with the tall flat side against the inside of the sheave/pulley with the short side facing the outer portion and the round part down.  Once all the OD weights are in place put the cam plate back in place along with the cam plate sliders very carefully.  You should now be holding the sheave/pulley with your thumb on one side holding the cam plate and your fingers on the sheave face so the weights do not slide/move/come out of place.  From this point on you DO NOT want to let go of the of this grip until I tell you different.  Put this assembly back into place on the machine (DO NOT LET GO YET!!!) and roll the assembly back and forth to make sure that you have the splines lined up and started from the shaft to the cam plate (STILL DO NOT LET GO YET!!!).  Start the nut on the cam place once the splines are started(STILL DONT LET GO YET!!!) and tighten the nut down all the way. NOW YOU CAN LET GO!!!  I stress this be 99.999% of the time people put OD weights in they do not hold firm pressure all the way through the process and one of the weights falls over or comes out of place.  This causes the machine to preform HORRIBLE and everyone asks questions about "Why is it doing so bad?".  If you take your time and hold the cam plate and sheave together you will be able to do it.  At this point reassembly is per normal.  Torque the nut and install the CVT cover and whatever else you did to get in there.

My mini review of them is as follows - I did notice better low end pull and slightly more top end on mine (i stayed with the same weight sliders so they are only different in shape).  Also as my sliders were damaged the shift out and back problem was fixed and I have not noticed any inconsistencies in its shifting.  The OD weights are pricey at $80 vs normal rollers but if you are looking for slightly better clutch performance than there is no other alternative.  I wanted to try slightly lighter weights but they were unavailable at the time so I may swap out for lighter ones down the road and report back after that.  Sorry no pictures this time as I was in a hurry.  The whole process on my Zfoce 800ex took 35 min to do so its not to bad of a job.

This may sound stupid, but what are the benefits of installing Dr.Pulley OD weights? How do they work?

[2015 Z Force 800 53/Trail EPS]

This may sound stupid, but what are the benefits of installing Dr.Pulley OD weights? How do they work?

Springs and weights offer resistance and force. Where the spring in the driven clutch requires a certain amount to force to overcome the resistance it has depending on it's setting or clocking, to effect shift-out or parting of the sheaves, the primary or drive clutch generates that force derived from centrifugal effect of spinning weights. The weight of those weights (or in this case rollers or sliders) determines how much force it will generate at a given RPM. So...its all part of clutch tuning. This is important to overcome things like extra weight, larger tires, altitude, types of riding...ect. To answer your question in a short way, a lighter weight in the primary will require the engine to be run at a higher RPM to generate the same force as it did with heavier weights. This and other tuning will help place the engine in or closer to the RPM where it develops the best power or torque for the needed performance. And using sliders over the rollers will allow a wider range of movement of that primary to give you a little lower ratio at starting and a little more closing on the top end which increases the ratio and adds top end. It's not a lot..but every little but counts.  Hope this helps.