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i'llDooit
Well-known member
so in your opinion, will a balanced primary have that nagging bog,,, if it did not prior to balancing?
Balancing question ????
- Thread starter SNOWBUM101
- Start date
so in your opinion, will a balanced primary have that nagging bog,,, if it did not prior to balancing?
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Seeyacop
Well-known member
Beware balancing the primary....
My buddy and I wanted to balance our TRA clutches last year. He decided to do his first and within 2 rides it cracked all the way through because so much material was removed by the balancer. I won't name names on who it was but they have been mentioned already in this thread. When he got his clutch back before putting it on he noticed how thin the material on the primary was where they drilled into it. They told him, it will work fine we have never had one break.
Guess what? It cracked in the exact spot we thought it would. Fortunately the balancer ponied up and supplied a new primary. He is now back to running a non balanced OE skidoo out of the box primary. After this I decided not to balance. Some may be worse than others and perhaps his needed too much taken off to make it balance.
By the way Gus knows his stuff!
My buddy and I wanted to balance our TRA clutches last year. He decided to do his first and within 2 rides it cracked all the way through because so much material was removed by the balancer. I won't name names on who it was but they have been mentioned already in this thread. When he got his clutch back before putting it on he noticed how thin the material on the primary was where they drilled into it. They told him, it will work fine we have never had one break.
Guess what? It cracked in the exact spot we thought it would. Fortunately the balancer ponied up and supplied a new primary. He is now back to running a non balanced OE skidoo out of the box primary. After this I decided not to balance. Some may be worse than others and perhaps his needed too much taken off to make it balance.
By the way Gus knows his stuff!
Well lets be honest. Balancer made an attempt to correct something that never should have been sold by BRP if it was that far out. This event probably saved your bottom end from motor failure. Hmm two side to every story isnt there
Balancing Question?
This is the other side of the story. I've been spin balancing clutches for 20 to 25 years. And before 2008 Ski-Doo clutches were only out of balance on a average about 10 to 15 grams on the front end and 1 to 5 grams on back end. Now the 2008 thru 2011 average 15 grams to 30 grams on the front end and still 1 to 5 grams on back end. And because of this large unbalance I no longer drill 20 to 25 holes in the front sheave. I mill the front edge down and keep the integrity or thickness the same but if they are out 28 grams like the last 2011 I did this week it will have a large area removed. If those two individuals had had their motor balanced that thin area on the clutch would not have cracked. My personal sled has alot of drilled holes and no cracks.
This is the other side of the story. I've been spin balancing clutches for 20 to 25 years. And before 2008 Ski-Doo clutches were only out of balance on a average about 10 to 15 grams on the front end and 1 to 5 grams on back end. Now the 2008 thru 2011 average 15 grams to 30 grams on the front end and still 1 to 5 grams on back end. And because of this large unbalance I no longer drill 20 to 25 holes in the front sheave. I mill the front edge down and keep the integrity or thickness the same but if they are out 28 grams like the last 2011 I did this week it will have a large area removed. If those two individuals had had their motor balanced that thin area on the clutch would not have cracked. My personal sled has alot of drilled holes and no cracks.
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sledsrock
Well-known member
Great info, now get back in the shop and get my clutch done......Please?
LOL
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Red-eye
Well-known member
I have seen a few TRA clutches that have casting flaws in them. I have seen a few that have cracked there also. Now if a hole was drilled near one of these flaws, it would make it crack sooner. Some of these flaws are hard to see and I am sure there are flaws deep inside. There are many sides to each story.
or sooner
Wow. That would scare me to bolt that on my sled. Does it run smooth now?
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Red-eye
Well-known member
That is a disaster just waiting to happen!
I find it hard to believe that clutch was out that much. Watching their video, I can't see how you balance a clutch that has worn parts in it. A clutch should be completely rebuilt before balancing. Never seen it stated that it had to be.
Once a clutch starts to wear, does it go out of balance? With belt forces, reverse, etc. how does it wear evenly?
With the two halves of the clutch surfaces being in contact with the belt on approx. 2/3 of the surface at any givin time, the clutch will always want to wear in such a way that balancing will be short lived.(just my opinion)
It seems more importand to keep your clutch clean and within specs. As soon as it gets worn rebuild and ride. ( I think a Rooster said that )
I find it hard to believe that clutch was out that much. Watching their video, I can't see how you balance a clutch that has worn parts in it. A clutch should be completely rebuilt before balancing. Never seen it stated that it had to be.
Once a clutch starts to wear, does it go out of balance? With belt forces, reverse, etc. how does it wear evenly?
With the two halves of the clutch surfaces being in contact with the belt on approx. 2/3 of the surface at any givin time, the clutch will always want to wear in such a way that balancing will be short lived.(just my opinion)
It seems more importand to keep your clutch clean and within specs. As soon as it gets worn rebuild and ride. ( I think a Rooster said that )
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i'llDooit
Well-known member
Roosterbuilt had there shop E-rect sled primary balanced. cockadoodle doooo!
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Red-eye
Well-known member
I know very little about balancing, but I do know a little about metal. The problem with taking metal off a clutch like that, is that it can crack on either side of the outter drill marks. Therefore becoming a risk of coming off as in a missile at 8000 rpm. Perks would have be better off in removing metal from the outter flange edge only or drilling right through the middle of the flange and not the edge. I have read that Perks is doing something simular now. Probably because of testing failures. No disrespect to them intended. R & D takes time. I have not seen any pics of this.
I find it hard to believe, with Roosters reputation, that he would put a clutch looking like that on one of his sleds. My guess is that it his clutch was done in the new way. Plus his would have been sent in top condition, as to make sure it was done right.
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jrt6457
Member
This clutch was sent to Perks last summer, it was my first time sending a clutch out to be balanced so i wasn't sure what to expect. I also thought it looked like a disaster waiting to happen and only ran it once.
I honestly didn't notice much of difference in the vibration of the sled, vibrated alot before and after.
Ended up putting a new crank in and showed a mechanic(30 yrs of wrenching on sleds, including owning a skidoo dealership at one time) doing the work the balanced clutch. He was in shock and said he had never seen a clutch balanced this way.
He took the clutch to another balacing shop he uses and they told him it was way off exactly where all the material had been removed. He also showed a skidoo r&d guy who said without a doubt it would eventually come apart.
I didn't want to chance it and ended up buying a new sheave.
I honestly didn't notice much of difference in the vibration of the sled, vibrated alot before and after.
Ended up putting a new crank in and showed a mechanic(30 yrs of wrenching on sleds, including owning a skidoo dealership at one time) doing the work the balanced clutch. He was in shock and said he had never seen a clutch balanced this way.
He took the clutch to another balacing shop he uses and they told him it was way off exactly where all the material had been removed. He also showed a skidoo r&d guy who said without a doubt it would eventually come apart.
I didn't want to chance it and ended up buying a new sheave.
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i'llDooit
Well-known member
perks comented on this type of mutalation to the primary being done different now. SOME PICS of the new way would be nice. i would never send my clutch out to have that done to it. if i got the clutch back and it looked like that,,,, i would ask for a new clutch.
Balancing Question
The clutch in those pictures was out of balance 30 grams on the front end (where all holes are). As I mentioned in a previous thread we mill down the front edge of the sheave now. Let me explain what 30 grams of unbalance generates = 120 grams or 975 LBS of centrifugal force at 8000 rpm. at the crank radius, then add the 115 grams that's in the crank (not counting the 115 grams of unbalance on the Mag. side of crank at the opposite angle) and he now has 235 grams of unbalance if the clutch is put on at the same angle of unbalance on the crank which generates 1800 + LBS. of centrifugal force and THAT'S WHY HE HAS PUT 3 CRANKS IN THAT SLED.
His dealer called me and tried to tell me that I didn't know what I was doing. He also told me he had a Hines Balance Machine. I asked him a couple of questions about balancing come to find out he didn't know much. I first told him I would do the customer's motor for half price but he didn't believe it was the crank, I then told him to get a hold of this guy and I would do it for FREE just to show both of them. I would put my balance experience up to any one in the world.
I have several Polaris 800 sleds that have been balanced out there that have alot more then 3000 miles since 2005 that have not broken another crank but who had replaced one to two before my balance job.
The clutch in those pictures was out of balance 30 grams on the front end (where all holes are). As I mentioned in a previous thread we mill down the front edge of the sheave now. Let me explain what 30 grams of unbalance generates = 120 grams or 975 LBS of centrifugal force at 8000 rpm. at the crank radius, then add the 115 grams that's in the crank (not counting the 115 grams of unbalance on the Mag. side of crank at the opposite angle) and he now has 235 grams of unbalance if the clutch is put on at the same angle of unbalance on the crank which generates 1800 + LBS. of centrifugal force and THAT'S WHY HE HAS PUT 3 CRANKS IN THAT SLED.His dealer called me and tried to tell me that I didn't know what I was doing. He also told me he had a Hines Balance Machine. I asked him a couple of questions about balancing come to find out he didn't know much. I first told him I would do the customer's motor for half price but he didn't believe it was the crank, I then told him to get a hold of this guy and I would do it for FREE just to show both of them. I would put my balance experience up to any one in the world.
I have several Polaris 800 sleds that have been balanced out there that have alot more then 3000 miles since 2005 that have not broken another crank but who had replaced one to two before my balance job.
I
i'llDooit
Well-known member
His dealer called me and tried to tell me that I didn't know what I was doing. He also told me he had a Hines Balance Machine. I asked him a couple of questions about balancing come to find out he didn't know much. I first told him I would do the customer's motor for half price but he didn't believe it was the crank, I then told him to get a hold of this guy and I would do it for FREE just to show both of them. I would put my balance experience up to any one in the world.
I have several Polaris 800 sleds that have been balanced out there that have alot more then 3000 miles since 2005 that have not broken another crank but who had replaced one to two before my balance job.
I think everyone would like to see what milling down the front edge of the sheave will look like as apposed to the shotgun dimple look!
