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I’m looking to add a clutch kit to my 05 stock 660, I do have plans to add aftermarket exhaust with jetting and possibly a cam so question is with my riding mostly trails a occasional feeling of getting muddy I’m looking for a clutch kit where when I come out of a slow corner I easily break my 26” tires lose and lift the front a little what kind of kit would help me achieve this thanks for any input
 

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I’m looking to add a clutch kit to my 05 stock 660, I do have plans to add aftermarket exhaust with jetting and possibly a cam so question is with my riding mostly trails a occasional feeling of getting muddy I’m looking for a clutch kit where when I come out of a slow corner I easily break my 26” tires lose and lift the front a little what kind of kit would help me achieve this thanks for any input
The first thing myself and most of the senior members on here and the experience members are going to tell you, do not buy a clutch kit per say. By the part you need individually. It's going to be cheaper You're not going to have a bunch of stuff that you don't need and you'll do it once and do it right.

First a few things we need to know before we can recommend anything. You've already told us what your bike is, what exactly do you have for tires, what are your writing conditions like in general are you just a trail rider or are you a mudder or what mix of those for example.

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My stock 660 could do that.
You really only need a 700 spring (orange) or for a little more use a purple spring.
Lift the tires out of the corner remove the sway bar. Practice this first.
 

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Welcome from Colorado.
Is this a new bike to you, have you been inside the c.v.t. cover to inspect/understand how the systems parts work together?
There's several c.v.t. mods which the 660 can accept, in my case riding at high elevation (down on Ox at high altitude) required more than a spring for better performance.
First of all I highly recommend leaving the jetting alone, and stay with the stock cam if the bike is running well and the engine doesn't require a re-build due to worn parts. I ride from 3000ft. to 14,000ft. on the stock carb and opened the air box lid flow with several holes, I tried reducing the amount of gas delivered to learn that was the wrong thing to do. I needed more air, not less gas.
https://flic.kr/p/fKjh1X
I run 26" tires (true to stated size) which are 11% taller so I raised the pulley ratio 12% to get the stock low-end feel back....then I raised the pulley more for better than stock low-end pull.
I've never unhooked the sway bar, give that a try and let us know your thoughts.
 

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Discussion Starter · #5 ·
The first thing myself and most of the senior members on here and the experience members are going to tell you, do not buy a clutch kit per say. By the part you need individually. It's going to be cheaper You're not going to have a bunch of stuff that you don't need and you'll do it once and do it right.

First a few things we need to know before we can recommend anything. You've already told us what your bike is, what exactly do you have for tires, what are your writing conditions like in general are you just a trail rider or are you a mudder or what mix of those for example.

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First of all I really appreciate the response! My tires are
The first thing myself and most of the senior members on here and the experience members are going to tell you, do not buy a clutch kit per say. By the part you need individually. It's going to be cheaper You're not going to have a bunch of stuff that you don't need and you'll do it once and do it right.

First a few things we need to know before we can recommend anything. You've already told us what your bike is, what exactly do you have for tires, what are your writing conditions like in general are you just a trail rider or are you a mudder or what mix of those for example.

Sent from my Pixel 5 using Tapatalk
First of all I really appreciate the response looking forward to learning more about my quad on this level. My tires are Maxxis Big horn 26/9/12s on the front 26/10/12s on the back with itp rims so they weight a lot more than the stock aluminum rims and tires. As for riding environment My guess would be 80% trail 20% mudding sometimes maybe even less mudding than that
 

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Discussion Starter · #6 ·
Welcome from Colorado.
Is this a new bike to you, have you been inside the c.v.t. cover to inspect/understand how the systems parts work together?
There's several c.v.t. mods which the 660 can accept, in my case riding at high elevation (down on Ox at high altitude) required more than a spring for better performance.
First of all I highly recommend leaving the jetting alone, and stay with the stock cam if the bike is running well and the engine doesn't require a re-build due to worn parts. I ride from 3000ft. to 14,000ft. on the stock carb and opened the air box lid flow with several holes, I tried reducing the amount of gas delivered to learn that was the wrong thing to do. I needed more air, not less gas.
https://flic.kr/p/fKjh1X
I run 26" tires (true to stated size) which are 11% taller so I raised the pulley ratio 12% to get the stock low-end feel back....then I raised the pulley more for better than stock low-end pull.
I've never unhooked the sway bar, give that a try and let us know your thoughts.
When I first got the quad there was problems in the cvt from a previous owner (he stripped the threads off of the primary sheave) I’ve since fixed that and have been inside it a time or two running it with the cover off but the cage on just to ensure everything was working the way it should which it’s seemed to be fine for months now after fixing that I learned the head gasket needed replaced so I did that and also replaced the timing chain while I was in there due to one of the links being worn thin somehow from previous owner this was also months ago and it hasn’t skipped a beat yet. Only reason I mention a cam and exhaust is because of the urge for a little more snap in the throttle but maybe some clutch modifications would be a much better bet to see if it’ll give me what I’m looking for before I go into the engine itself
 

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Discussion Starter · #7 ·
When I first got the quad there was problems in the cvt from a previous owner (he stripped the threads off of the primary sheave) I’ve since fixed that and have been inside it a time or two running it with the cover off but the cage on just to ensure everything was working the way it should which it’s seemed to be fine for months now after fixing that I learned the head gasket needed replaced so I did that and also replaced the timing chain while I was in there due to one of the links being worn thin somehow from previous owner this was also months ago and it hasn’t skipped a beat yet. Only reason I mention a cam and exhaust is because of the urge for a little more snap in the throttle but maybe some clutch modifications would be a much better bet to see if it’ll give me what I’m looking for before I go into the engine itself
Also another question I would I know that my atv is running at its peak performance for being stock? I’ve checked the plug and it does look fine after tweaking it a few times after getting the carb rebuilt
 

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Discussion Starter · #8 ·
My stock 660 could do that.
You really only need a 700 spring (orange) or for a little more use a purple spring.
Lift the tires out of the corner remove the sway bar. Practice this first.
When you say for a little more get the purple spring not to sound dumb but what do you mean by that?
 

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When you say for a little more get the purple spring not to sound dumb but what do you mean by that?
The little more is referring to spring tension effecting the back-shift rate for engine decel, and up-shift rate for increasing speed.

C.V.T. MODS ARE THE BEST BANG FOR THE BUCK!
I think the back-shift rate is more important to focus on.
Changing the secondary spring is actually more important to prevent belt slip with higher than stock pulley ratio(s) which magnify torque to the belt. The higher tension puts more squish on the belt in the secondary to prevent belt slip, so then also requires more rotational force on the weights to move the movable primary, which means heavier weights or more engine r.p.m.
Getting the right combination can take time depending on your want and how much time youy have to get the set-up right.
The trick to this whole deal is to determine what tires you want, as the tires are part of the total drive line to the ground. Mostly its determining the tire diameter which is critical, yet many here think its the tire weight that causes a drag to the drive system.
Most here have learned the purple spring is a great choice which I confirm.
Now its important for YOU to determine your stock pulley ration, be very accurate in the measuring as very small changes can be felt. Also c.v.t. mods magnify each other as the ratio gets higher, they build upon them self.
I run a very high ratio for get snap by magnified torque to the belt. My 660 will go from a standing start to 20 m.p.h. in one second, in 20ft. and the belt doesn't slip.
Once I had great take off bite to 20 m.p.h. I worked on continued great forward bite as the Griz gained speed, I added heavier weights to keep the engine in the torque producing range longer as the heavier weights forced the primary to close faster than stock.
As I got the ratio up which caused a lowering of top speed I focused on a cut cam-plate to add top speed with the heavier weights driving the primary.
 

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The little more is referring to spring tension effecting the back-shift rate for engine decel, and up-shift rate for increasing speed.

C.V.T. MODS ARE THE BEST BANG FOR THE BUCK!
I think the back-shift rate is more important to focus on.
Changing the secondary spring is actually more important to prevent belt slip with higher than stock pulley ratio(s) which magnify torque to the belt. The higher tension puts more squish on the belt in the secondary to prevent belt slip, so then also requires more rotational force on the weights to move the movable primary, which means heavier weights or more engine r.p.m.
Getting the right combination can take time depending on your want and how much time youy have to get the set-up right.
The trick to this whole deal is to determine what tires you want, as the tires are part of the total drive line to the ground. Mostly its determining the tire diameter which is critical, yet many here think its the tire weight that causes a drag to the drive system.
Most here have learned the purple spring is a great choice which I confirm.
Now its important for YOU to determine your stock pulley ration, be very accurate in the measuring as very small changes can be felt. Also c.v.t. mods magnify each other as the ratio gets higher, they build upon them self.
I run a very high ratio for get snap by magnified torque to the belt. My 660 will go from a standing start to 20 m.p.h. in one second, in 20ft. and the belt doesn't slip.
Once I had great take off bite to 20 m.p.h. I worked on continued great forward bite as the Griz gained speed, I added heavier weights to keep the engine in the torque producing range longer as the heavier weights forced the primary to close faster than stock.
As I got the ratio up which caused a lowering of top speed I focused on a cut cam-plate to add top speed with the heavier weights driving the primary.
Fyi, tire weight does cause drag on the system. It also depends on where that weight is on the tire. You take two tires of exactly the same diameter but one has much larger lugs than the other one, yet in this case for an example because of the casing of the tire being lighter weight we will say that the tire with the larger lugs is actually lighter than the other one. The first tire being the same diameter but lighter yet having most of its weight at the outer diameter of the tire will actually put more drag on the system then the heavier tire. If they were both the same weight tire, the one with the more mass at the outside diameter of the tire will still cause more drag on the system. Now as you mention, start changing diameter and that just throws another kink in the system to try to figure out. Diameter mass and centrifugal force of that mass all combined together to play a part in the amount of drag on the drive train.

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I am so happy, a good clutch thread. 😀
 
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I am so happy, a good clutch thread.
Oh yeah it always starts out with the words clutch kit then the next thing you know you're talking shims and tires and weights what colors shoes you're going to wear how heavy is your helmet And did you poop after your last meal.......
Oh wait I'm mixing up the different kinds of low end torque

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I am waiting for the moderators to need to step in and sort out the flames, WE ALL have STRONG opinions on clutching.
 

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Seriously, try and figure out what you have before you jump in, somebody might have already modified your machine.
 

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Oh yeah it always starts out with the words clutch kit then the next thing you know you're talking shims and tires and weights what colors shoes you're going to wear how heavy is your helmet And did you poop after your last meal.......
Oh wait I'm mixing up the different kinds of low end torque

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I guess you need to be an anal expert to mod around here, I knew you had expertise in something.
 
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