Section 4 - Clutching - Drive Belts (types,alignment)
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Picture NOTES, if the wording on last pictures is difficult to read, try printing them out, believe this would HELP. ALSO, posted this thread out of sequence, due to the fact that there are some very good individual posts already on the FORUM, so please guys, add links to the originals in this one.
DRIVE BELTS
The belts that we can purchase currently vary from a fabric type cover to the types that have ridges(rigs,cogs), ranging from small to large sizes. The compounds that the belts are constructed of range from rubber,fiberglass cords to Kevlar.
The latest types are those that have cogs on the top of the belt. These cogs promote better belt cooling(more exposed surface area) and tend to be more flexible. Pictured below are 2 examples of the Cogged Type. One is the standard RZR belt referred to as the “113”, which is the last 3 number of the part #, the other belt is the SEVERE DUTY belt from EPI.
SIDE VIEW
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TOP VIEW
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BOTTOM VIEW
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WIDTH COMPARION (reason EPI wants you to use the white plastic spacer)
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BOTTOM COG COMPARISON
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There ARE a number of belt manufactures/sellers including EPI,Gates,Dayco,Wasteland Peformance,Polaris, just to name a few.
Some DO’s & DON’Ts
One of the best things that you can do before installing a NEW Belt is to wash it with soapy warm water, then allow it to totally dry before installing in the clutch. This washing process will remove any manufacturing/chemical residues that may have been left on the belt when it was made.
It should also be a Good practice to clean the clutch area with an air compressor to remove any belt dust or just general dust.
The belt when installed in the Clutch SHOULD always be installed, so that the writing,name or printing that is on the outside surface of the belt can be read from LEFT to RIGHT. This may be rather simple, but actually the Belts are NOT constructed to be
BI-Directional and this will make it much simplier to remember how you originally had the belt installed if it must be removed.
When a NEW belt is installed in the clutch, it is HIGHLY advised to allow the belt to be broken in. This means that you should NOT do any Full Power or WOT(Wide Open Throttle) runs for any sustained period of time.
I think that it’s also a good practice to measure the belt(both the overall outer diameter as well as the width of the belt. The BIGGEST reason I feel that this should be done is NOT ALL BELTS are created the same even if by the same manufacturer. There may be as much as ½” difference in circumference.
BELT DEFLECTION OR FREEPLAY
Belt Deflection is (in simple terms) is checking the center distance of the belt when it is installed in the Primay/Secondary Clutch. The simple method of checking this would be to place a straight edge across the top of the belt between the Primary and Secondary Clutch Sheaves, then with you thumb, just apply a minimal amount of downward pressure to the top of the belt. The distance between straight edge and the belt should be around 1 ¼ “. If the measurement is not close, you must either get a NEW Belt with a different length or you use Shims in the Secondary Clutch (BETWEEN the 2 Sheaves, NOT to be confused with the SPACERS or SHIMS that are located BEHIND the Secondary Clutch on the shaft between the Clutch and the Transmission.
IF the belt is TOO SHORT, it will ride TOO Deep in the Secondary Clutch, kind of wearing the bearing, resulting in a SLOW feeling ride and result or feel like you are starting out in TOO high of a gear. The engine might even BOG and you could have Bad LOW END Peformance as well as difficulty trying to shift the transmission into gear. This is due to the Secondary Clutch being engaged and spinning even thought you may be in park or neutral.. IF the belt is TOO LONG, it will ride up or outside of the Secondary Clutch sheaves resulting in the machine slowing down due to the fact that it will not get pulled deeper into the Secondary and produce Extreme Belt Slipping..
**** I will leave these MEASUREMENT methods to each individual method of checking, JUST be consistent. It’s also a good idea to check the Clutch operating specs to insure that you’re not trying to install a belt that is either TOO WIDE or TOO NARROW. However, it is possible on the Secondary Clutch to ADD or REMOVE shims to correct for some of these conditions.
I feel that it’s a good practice to periodically check the belt width for wear. I can’t confirm the tolerance, but I’ve been told if the belt is worn more that 1/8”, they are too narrow to be used. The reason for this tolerance is really pretty logically. If the belt is worn, then it will be pulled further into the Secondary(Driven) sheaves in low gear(ratio) resulting in a higher ratio on engagement, kinda of like starting out in 2nd gear if you had a manual transmission. This will bog the RZR on take off and it would tend to slow your speed down. The effect in the Primary Clutch is just as bad, in that the Primary sheaves will SLAM on the belt, thus adding another added stress factor if the normal belt slip on engagement wasn’t enough of a problem to overcome.
CLUTCH ALIGNMENT
This is critical to both performance as well as insuring that the life of the belt is not minimized to belt WEAR.
The simpliest form of a misalignment is if the Secondary Clutch is not properly OFFSET from the transmission. This condition can be checked by using an alignment tool as show in the picture below, or by placing a straight edge behind the Primary and Secondary Clutch Sheaves and using a caliper to measure the distance of the FRONT and the BACK of the Secondary Clutch Sheaves to the straight edge. This measurement can be used to determine if you have the proper OFFSET or a WORSE problem of a misaligned engine. If the OFFSET is not to Specifications, there are SPACERS or SHIMS, located between the Transmission and the back of the Secondary Clutch, that can be added or taken away depending upon the inconsistency of the OFFSET.
The other two types of misalignment are I believe rather Rare due to the fact that the Engine & Transmission are Hooked(Tied) together. I could be incorrect about this statement, so CORRECT me if I’m wrong.
The engine or transmission could be misaligned resulting in the engine and secondary shafts not being PARALLEL with each other, OR the engine and drive shaft are not parallel HORIZONTALLY with each other, meaning either the engine or transmission is sitting TOO high. I’m not going into any detail on these topics, since the dealerships would need to check,determine & fix these conditions.(possible manufacturing defect)
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CLUTCH COOLING
Since We ALL have RZR’s and POLARIS has done a pretty decent job of enclosing both clutches in a sealed compartment, the cooling consideration of the clutches is not too great. The fact that the sheaves are made of aluminum and air is being circulated around the clutch cavity is an improvement of past setups. In addition, the back side of the Primary Clutch Sheave has fins or ribs to act as vacuum fan to draw air in, circulate it and discharge the warm air out into the engine area. The fact that the Primary Clutch is OPEN also added in cooling that clutch. With the inclusion of the TOP COG belt, much of problems with NORMAL clutch overheating have been addressed. This doesn’t however mean that you can FORGET maintenance of the system. Not a bad idea to periodically check the clutch discharge vent to insure you don’t have mud or a birds nest in it as well as attempting to insure that the air being drawn into the clutch cavity is as clean as it could be, BASICLY the same consideration that you go thru with the air flowing in the engine.
BELT CONDITONS/CAUSE
I have copied a couple of pages from the Clutch Tuning Handbook by Olav Aaen
Due to their Simplicity and Ease of Understanding.
![]()
![]()
DRIVE BELTS
The belts that we can purchase currently vary from a fabric type cover to the types that have ridges(rigs,cogs), ranging from small to large sizes. The compounds that the belts are constructed of range from rubber,fiberglass cords to Kevlar.
The latest types are those that have cogs on the top of the belt. These cogs promote better belt cooling(more exposed surface area) and tend to be more flexible. Pictured below are 2 examples of the Cogged Type. One is the standard RZR belt referred to as the “113”, which is the last 3 number of the part #, the other belt is the SEVERE DUTY belt from EPI.
SIDE VIEW
TOP VIEW
BOTTOM VIEW
WIDTH COMPARION (reason EPI wants you to use the white plastic spacer)
BOTTOM COG COMPARISON
There ARE a number of belt manufactures/sellers including EPI,Gates,Dayco,Wasteland Peformance,Polaris, just to name a few.
Some DO’s & DON’Ts
One of the best things that you can do before installing a NEW Belt is to wash it with soapy warm water, then allow it to totally dry before installing in the clutch. This washing process will remove any manufacturing/chemical residues that may have been left on the belt when it was made.
It should also be a Good practice to clean the clutch area with an air compressor to remove any belt dust or just general dust.
The belt when installed in the Clutch SHOULD always be installed, so that the writing,name or printing that is on the outside surface of the belt can be read from LEFT to RIGHT. This may be rather simple, but actually the Belts are NOT constructed to be
BI-Directional and this will make it much simplier to remember how you originally had the belt installed if it must be removed.
When a NEW belt is installed in the clutch, it is HIGHLY advised to allow the belt to be broken in. This means that you should NOT do any Full Power or WOT(Wide Open Throttle) runs for any sustained period of time.
I think that it’s also a good practice to measure the belt(both the overall outer diameter as well as the width of the belt. The BIGGEST reason I feel that this should be done is NOT ALL BELTS are created the same even if by the same manufacturer. There may be as much as ½” difference in circumference.
BELT DEFLECTION OR FREEPLAY
Belt Deflection is (in simple terms) is checking the center distance of the belt when it is installed in the Primay/Secondary Clutch. The simple method of checking this would be to place a straight edge across the top of the belt between the Primary and Secondary Clutch Sheaves, then with you thumb, just apply a minimal amount of downward pressure to the top of the belt. The distance between straight edge and the belt should be around 1 ¼ “. If the measurement is not close, you must either get a NEW Belt with a different length or you use Shims in the Secondary Clutch (BETWEEN the 2 Sheaves, NOT to be confused with the SPACERS or SHIMS that are located BEHIND the Secondary Clutch on the shaft between the Clutch and the Transmission.
IF the belt is TOO SHORT, it will ride TOO Deep in the Secondary Clutch, kind of wearing the bearing, resulting in a SLOW feeling ride and result or feel like you are starting out in TOO high of a gear. The engine might even BOG and you could have Bad LOW END Peformance as well as difficulty trying to shift the transmission into gear. This is due to the Secondary Clutch being engaged and spinning even thought you may be in park or neutral.. IF the belt is TOO LONG, it will ride up or outside of the Secondary Clutch sheaves resulting in the machine slowing down due to the fact that it will not get pulled deeper into the Secondary and produce Extreme Belt Slipping..
**** I will leave these MEASUREMENT methods to each individual method of checking, JUST be consistent. It’s also a good idea to check the Clutch operating specs to insure that you’re not trying to install a belt that is either TOO WIDE or TOO NARROW. However, it is possible on the Secondary Clutch to ADD or REMOVE shims to correct for some of these conditions.
I feel that it’s a good practice to periodically check the belt width for wear. I can’t confirm the tolerance, but I’ve been told if the belt is worn more that 1/8”, they are too narrow to be used. The reason for this tolerance is really pretty logically. If the belt is worn, then it will be pulled further into the Secondary(Driven) sheaves in low gear(ratio) resulting in a higher ratio on engagement, kinda of like starting out in 2nd gear if you had a manual transmission. This will bog the RZR on take off and it would tend to slow your speed down. The effect in the Primary Clutch is just as bad, in that the Primary sheaves will SLAM on the belt, thus adding another added stress factor if the normal belt slip on engagement wasn’t enough of a problem to overcome.
CLUTCH ALIGNMENT
This is critical to both performance as well as insuring that the life of the belt is not minimized to belt WEAR.
The simpliest form of a misalignment is if the Secondary Clutch is not properly OFFSET from the transmission. This condition can be checked by using an alignment tool as show in the picture below, or by placing a straight edge behind the Primary and Secondary Clutch Sheaves and using a caliper to measure the distance of the FRONT and the BACK of the Secondary Clutch Sheaves to the straight edge. This measurement can be used to determine if you have the proper OFFSET or a WORSE problem of a misaligned engine. If the OFFSET is not to Specifications, there are SPACERS or SHIMS, located between the Transmission and the back of the Secondary Clutch, that can be added or taken away depending upon the inconsistency of the OFFSET.
The other two types of misalignment are I believe rather Rare due to the fact that the Engine & Transmission are Hooked(Tied) together. I could be incorrect about this statement, so CORRECT me if I’m wrong.
The engine or transmission could be misaligned resulting in the engine and secondary shafts not being PARALLEL with each other, OR the engine and drive shaft are not parallel HORIZONTALLY with each other, meaning either the engine or transmission is sitting TOO high. I’m not going into any detail on these topics, since the dealerships would need to check,determine & fix these conditions.(possible manufacturing defect)
CLUTCH COOLING
Since We ALL have RZR’s and POLARIS has done a pretty decent job of enclosing both clutches in a sealed compartment, the cooling consideration of the clutches is not too great. The fact that the sheaves are made of aluminum and air is being circulated around the clutch cavity is an improvement of past setups. In addition, the back side of the Primary Clutch Sheave has fins or ribs to act as vacuum fan to draw air in, circulate it and discharge the warm air out into the engine area. The fact that the Primary Clutch is OPEN also added in cooling that clutch. With the inclusion of the TOP COG belt, much of problems with NORMAL clutch overheating have been addressed. This doesn’t however mean that you can FORGET maintenance of the system. Not a bad idea to periodically check the clutch discharge vent to insure you don’t have mud or a birds nest in it as well as attempting to insure that the air being drawn into the clutch cavity is as clean as it could be, BASICLY the same consideration that you go thru with the air flowing in the engine.
BELT CONDITONS/CAUSE
I have copied a couple of pages from the Clutch Tuning Handbook by Olav Aaen
Due to their Simplicity and Ease of Understanding.
