Primary clutch

[GreenMtnRx1]

On my Gt I was looking at the primary clutch and the marks on it show that the belt is only coming up to a inch from the top. Would it be better to have that come closer to the top.

 

[ROCKERDAN]

only way it will come to near top is if you are hitting your theoretical top speed..which 130+ on radar.....

dan

 

[kviper]

You will not get the belt to the top unless you have the primary clutch and helix in the driven clutch machined to allow them to shift all the way out in to over drive. (aprox 1.1 to 1) Matt at the speed shop (BBY 2000 in here) can take care of that for you. If you are 1" frome the top you are not even to it's current capacity. kviper

 

[Racy2]

Kviper, my dealer wanted to machine my primary but then I heard that you will have to gear down as 150 HP will not pull it when it shitfs out. Your thoughts on that.

 

[ROCKERDAN]

You will not get the belt to the top unless you have the primary clutch and helix in the driven clutch machined to allow them to shift all the way out in to over drive. (aprox 1.1 to 1) Matt at the speed shop (BBY 2000 in here) can take care of that for you. If you are 1" frome the top you are not even to it's current capacity. kviper

i agree machining is needed to make clutches come to top,however i think that is misleading alot of people..

you WILL NEVER get your belt to top with stock HP motor...so maching your clutch is a waist of money IMO..the only way to run out of gearing on stock sled(130+ radar) would be to have a SC or turbo...then all you simply do is go to 25 or 26 tooth top...

simply put,your sled is overgeared and will not have belt ride to top,unless you do it on a jackstand...you can gear it lower(23 top) and get belt closer to top,but that is when machining your clutch MIGHT be needed only.

hope this clarifys

dan

 

[Racy2]

Thanks Dan, My thoughts were the same as yours unless we are both wrong on this one.

 

[LazyBastard]

A combination of gearing WAY down and overdriving the clutches makes a sled REAL fun. My RX is overdriven and geared 23/42 (about 15% lower than stock). When going blisteringly fast (120+ on the gigglegauge), it just starts to creep over 10500 rpm.

The real advantage of doing this is to reduce belt stress (greatly improve efficiency and belt life) on engagement, as well as prolong the clutch life (won't groove nearly as bad at the center when geared down real far). Secondary advantages are you now get to blow the socks off any sled you race against, and pull wheelies on command at any speed.

 

[zipclean]

I don't really don't agree with your ideas on stock hp. can't pull the primary to to the top.Every 2 stroke I have owned pulled it to the top of prim. when clutched right.If the belt will not pull to the top then you have to clutch and gear or you aren't set right! Just how mine have all been.Maybe 4 strokes are different but the pencil marks should be worn off very close to the top.

 

[GreenMtnRx1]

I was thinking the higher the belt on the clutch the faster it will turn the secondary.

 

[GreenMtnRx1]

That motor should have the power to turn it with The belt at the top.

 

[ROCKERDAN]

I don't really don't agree with your ideas on stock hp. can't pull the primary to to the top.Every 2 stroke I have owned pulled it to the top of prim. when clutched right.If the belt will not pull to the top then you have to clutch and gear or you aren't set right! Just how mine have all been.Maybe 4 strokes are different but the pencil marks should be worn off very close to the top.

you guys are killing me here...its common theory what our sleds are geared for,and it is a fact that a 24/38 stock apex is theoretically geared for a top speed of about 131.98 mph when revved at 10,800rpms.

NOW,since the above statement is FACT,how can you expect your belt to ride to top of primary???...the only way to run it OUT OF GEAR and hit top of primary with belt would be to hit 131.98mph on radar gun!..and without a turbo or SC its impossible...that is a fact.

Now,alot of guys think marking there clutch with marker,then seeing it take off by belt means you are hitting that spot..not true.....if you run it on a stand or SPIN your track,it will overshift and take off the marker on primary.

You should only run belt to top of primary IF you gear down as i said before to 22 or 23 top,then the theoretical speed is reduced..and clutches are running to full shift..

I beleive if you gear down,it might be quicker,but you also need more traction to hook that quickness up...if not it will spin more...this is why yammie gears them tall,for more fuel economy at cruising and also less track spin at takeoff..

i beleive running your clutches out of gear is LESS EFFICIENT,then stock gearing for lake running and top speed running...and here is why..

If you run your clutches at low gearing and run belt to top of primary,you are now pulling your belt around a large diameter primary circle,but a very small diameter secondary circle..this becomes IN-EFFICIENT.....the motor for top speed running can much more easily pull the belt around two CLOSER sized circles...meaning the belt not so high into primary and not so low into secondary.

the main reason turbo and SC guys go UP in gearing to 25 and 26 top teeth is because it helps put power down upon takeoff(less track spin) and then can pull big top end numbers...most guys want to go to 26 to help their blown motors work more efficiently on top end...

Guys gearing to 23 top and running clutches to top,are wanting more quick bottom end and mid,which is fine but then you need to machine clutches to get the full shift on top.this is proven by many to be quicker and snappier in trails and bottom but i beleive will result in LOWER radar speeds on ice and in long hauls...anyone running speeds over 118+ on gun has used stock gearing or higher like turbo guys.

It all depends what you do and how you ride..radar and lake haulers stock(24) is best....trails and drag racers,short runs ect...23 top should make you quicker....you cant have it all,which is why yammies came with apex 24 and attacks with 23..they KNOW.


but the fact remains,you will never have belt run to top of primary with stock 24/38 gears unless you go 131.98 on radar at 10,800 rpms..just cant happen!

dan

 

[zipclean]

AS I said you have to gear and clutch ,and yes you CAN pull to the top if you want to.Mark a Polaris clutch and you will see why most have great top end after 1/2 mile.

 

[machj]

machz your wrong on the gearing therory 24/38 will spin faster then a 24/40 i know this because my 93 machz came with a 25/40 then i put a25/44 in it and controlled my spinning problem spinning your track in snow condions our good but to high of gearing is no good i think this apexs spin way to much just my therory

 

[ROCKERDAN]

machz your wrong on the gearing therory 24/38 will spin faster then a 24/40 i know this because my 93 machz came with a 25/40 then i put a25/44 in it and controlled my spinning problem spinning your track in snow condions our good but to high of gearing is no good i think this apexs spin way to much just my therory

machj..

you obviously didnt read closely...i never mentioned a 40 tooth anywhere....and my thoughts are strictly fact about stock gearing for an apex...not machs or any other sled.

if that polaris runs belt to top then it must be geared for the speed it is achieving on gun,this would be true with any sled...gearing it for 118 in theory ,then running 118 can happen easily,but gearing a sled for 130 and running 130,wont happen without more HP..

 

[snowbeast]

On my Gt I was looking at the primary clutch and the marks on it show that the belt is only coming up to a inch from the top. Would it be better to have that come closer to the top.

Ya you are loosing big top end,it should come to w/in 3/8 of an inch when properly shifted out at wfo for 1/4 of mile run at least with stock clutching,and the further you run the higher it may go until it is closed as far as it can go stock.. Now if you just cut your helix you will gain a little bit, and may be as close as 1/4 inch from top.