- Location
- savannah/hilton head
what is the difference between a setback and a standard skat trak pump, both performance and visually? i have a 12 vein but not sure which one it is.
skat trak pump
- Thread starter SurferSmurf
- Start date
- Location
- Lake Orion, Michigan
can someone explain the difference between standard and set back period?
that would be awesome!
sorry, i know this does not answer your question, hopefully not hijacking either.
that would be awesome!
sorry, i know this does not answer your question, hopefully not hijacking either.
dbrutherford
Parts Whore
- Location
- Fairmont, WV
If you go on Skat's website they have a pretty good description of the two. My understanding that a set back has a "shorter" stator section. That is instead of the veins being 3 inches in length from tip to tip they are say 2 inches. Therefore you would have a 1 inch set back pump. The 1 inch is accomidated for by using a 1 inch longer drive shaft or a 1 inch longer nose prop.
Advantages? Set back pumps are more for closed course top end speed. But then again I have read where the EME boats have the pump physicall moved back in the hull further. I don't know if they do this to 1) get the nozzle hanging out the back of teh ski more. Or 2) to have a bigger volume of water available infront of the prop.
I would just be stoked you have a magnum! A Kawie 750/800 new stainless cast one is around 1500
Advantages? Set back pumps are more for closed course top end speed. But then again I have read where the EME boats have the pump physicall moved back in the hull further. I don't know if they do this to 1) get the nozzle hanging out the back of teh ski more. Or 2) to have a bigger volume of water available infront of the prop.
I would just be stoked you have a magnum! A Kawie 750/800 new stainless cast one is around 1500
- Location
- savannah/hilton head
since the pump is a 140 and not 144 does it use a kawi impeller?
- Location
- Pueblo, CO
set back means the whole stator section is moved back in the pump. It has nothing to do with the length of the vanes. It does require a longer drive shaft. Supposedly they hook up better than non-set back pumps. I have run both and cant "feel" much difference... take that for what its worth
And it is not a kawi impeller, rather a specific Mag-pump impeller made by skat-trak for your 140mm pump.
And it is not a kawi impeller, rather a specific Mag-pump impeller made by skat-trak for your 140mm pump.
The setback has shorter veins than the regular. The length is taken off the front which allows the impeller to be further back . So it does have to do with the length of the veins.One reason the veins are shorter is that it reduces drag allowing for slightly higher speeds at a given rpm with no loss of bottom end. I found the setback to hookup better than the non and still run one in my SJ and SXR.
matter of fact i just looked at the skat site setback article and it confirms that the veins are not moved back but just shortened. Also mentions hookup improvment because of the additional stored water in the intake gullet.
If this is true then why all the work to mod driveshafts and veins? Wouldn't it just be easier to extend the front of the pump, slide the entire pump back, and modify the mounting points? What am I missing?
- Location
- savannah/hilton head
the veins are not just shorter. in my pump the veins are very thin which i would have to think would give you more internal volume and more thrust than a stock 144mm pump.
- Location
- Pueblo, CO
did not know that, thanks.
I never had tham side-by-side to compare
dbrutherford
Parts Whore
- Location
- Fairmont, WV
http://www.skat-trak.com/watercraft.html
Click Magnum Pump. Thereis some good reading on there that explains soem of these questions.
Stock stators are made out of aluminum. The Skats are made out of stainless steel. So they have the same strength but are much thinner talking up less space. I was also told that the stainless has a different amount of drag on the water than aluminum does. It is something with how they rough up the surface.
As far as moving the pump back, it is more work than just making a longer drive shaft or making a longer nose prop. You would have to lengthen you steering cable too if you moved the pump back.
The real gains is in the number of stator veins and their shape. Also the full out Skat Kawie pumps are all stainless so they weigh more. That keeps the rear of the ski in the water some more. I have never ridden a magnum pump ski but there has to be a reason every racer and most freestyle pros run them. I always hear the term "liquid traction" used. I still want one...
Click Magnum Pump. Thereis some good reading on there that explains soem of these questions.
Stock stators are made out of aluminum. The Skats are made out of stainless steel. So they have the same strength but are much thinner talking up less space. I was also told that the stainless has a different amount of drag on the water than aluminum does. It is something with how they rough up the surface.
As far as moving the pump back, it is more work than just making a longer drive shaft or making a longer nose prop. You would have to lengthen you steering cable too if you moved the pump back.
The real gains is in the number of stator veins and their shape. Also the full out Skat Kawie pumps are all stainless so they weigh more. That keeps the rear of the ski in the water some more. I have never ridden a magnum pump ski but there has to be a reason every racer and most freestyle pros run them. I always hear the term "liquid traction" used. I still want one...
irreplaceable pumps.the hook up is improved over oem.
the setback allows the veins to be a bit shorter therefore moving the impeller back and making the water intake area in front of impeller more voluminous.the # of veins also allows for smoother straightening of water after it leaves the impeller as each vein has less h2o to catch for each degree of rotation.
there's a tradeoff as the # of veins goes up,the total open area diminishes and restricts water flow.
the setback allows the veins to be a bit shorter therefore moving the impeller back and making the water intake area in front of impeller more voluminous.the # of veins also allows for smoother straightening of water after it leaves the impeller as each vein has less h2o to catch for each degree of rotation.
there's a tradeoff as the # of veins goes up,the total open area diminishes and restricts water flow.
If you go on Skat's website they have a pretty good description of the two. My understanding that a set back has a "shorter" stator section. That is instead of the veins being 3 inches in length from tip to tip they are say 2 inches. Therefore you would have a 1 inch set back pump. The 1 inch is accomidated for by using a 1 inch longer drive shaft or a 1 inch longer nose prop.
Advantages? Set back pumps are more for closed course top end speed. But then again I have read where the EME boats have the pump physicall moved back in the hull further. I don't know if they do this to 1) get the nozzle hanging out the back of teh ski more. Or 2) to have a bigger volume of water available infront of the prop.
I would just be stoked you have a magnum! A Kawie 750/800 new stainless cast one is around 1500
Good answer. Short and sweet, the set back "pump" (not to be confused with setting an impeller back in the pump) produces better speed for closed course.
David
I agree, there's no real hook up gain with the set back PUMP. The vanes are shorter though. Requires a longer shaft to reach the coupler, but the nozzle assembly is in the same position.
David
There's a lot more to it than that. The hub is 15mm larger, there are more vanes, and a different angle to them. All of which produce better hook up and bottom end.
David
scottie mac
X-
Dave,
That Kawi in your avatar is one nice looking ski!!!
And, just wanted to give a shout out that Dave does great work. If you need a prop fixed, pitched, ordered, etc. he is your man.
Scottie Mac
That Kawi in your avatar is one nice looking ski!!!
And, just wanted to give a shout out that Dave does great work. If you need a prop fixed, pitched, ordered, etc. he is your man.
Scottie Mac