ktm 500 vs 450

CB-BLR

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I also believe that the second video/article showing 40 ft/lbs of torque and 60hp are of a 2019 500...which is down about 5hp and tq below a 2020 bikes.

Chris
 

byeatts

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yes i know 500 make low hp stock
but on aftermarket ecu they make 13-15 hp more , so stock hp is noting to compare to aftermarket ecu .
the 500 completely uncorked with ECU and exhaust does make about the same HP as the 450 race bike with slightly more torque at lower RPM., However it will still hit rev limiter all day long at much lower rpm,s.. I have a complete performance built 500 here. It will not hang with the higher RPM of the 450 we have here, We run them side by side , the 500 is easy to ride since you dont need to open her up and can short shift and great for newer riders or heavy riders, Of course ewe who have a 500 will never comprehend the facts about RPM which relates to track speed with a gearbox transmission. No dyno has ever shown 13-15 hp over a 450 race motor. The uncorked 500 dyno was 53 hp at the wheels, thats similar to the 450 race motor and the 500 made more torque at mid throttle and then easily hits rev limiter , ran with both PR2 and Raze ECU,s.
 

CB-BLR

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the 500 completely uncorked with ECU and exhaust does make about the same HP as the 450 race bike with slightly more torque at lower RPM., However it will still hit rev limiter all day long at much lower rpm,s.. I have a complete performance built 500 here. It will not hang with the higher RPM of the 450 we have here, We run them side by side , the 500 is easy to ride since you dont need to open her up and can short shift and great for newer riders or heavy riders, Of course ewe who have a 500 will never comprehend the facts about RPM which relates to track speed with a gearbox transmission. No dyno has ever shown 13-15 hp over a 450 race motor. The uncorked 500 dyno was 53 hp at the wheels, thats similar to the 450 race motor and the 500 made more torque at mid throttle and then easily hits rev limiter , ran with both PR2 and Raze ECU,s.
A few things to take into consideration here...You will never even get close to the potential of the 500 unless you mod or switch the throttle body to a 44mm like on the 450sx...this is worth 4-5 hp and 4-5 ft/lbs of torque...it also revs much quicker. Second point is that when dynoing both the stock PR2 and Raze ECU's on the dyno...after getting the unlock codes and appropriate cabling...we were able to get another 2-3 hp and ft/lbs by writing custom tunes for the bikes...and the rev limiter is raised to 10.5k so that the bike runs out of steam before hitting the rev limiter. I completely agree that both the 450sx and the 500 motors make almost the exact horsepower...the 500 at 9650 rpm, and the 450 at 11.1k rpm...but the 500 almost always is around 10 ft/lbs of torque up over the 450...and over a wider rpm range. Several companies are looking into trying the 450sx cams in the 500 to extend rpm without loosing that glorious torque...and a couple of other companies are looking at custom cams to do the same thing. Shortly here, I will be trying out the 450sx stator on the 500 as it is smaller and lighter. It does not put out enough juice to power lights and electric grips...but should let the 500 rev quicker. We shall see if that is a good thing or not. It should be noted that the 450xc has a stator that is more similar to the 500's than the 450sx.

On a side note...talking about the Thumper Racing 490 kit for the 450sx...it is wonderfully fun to ride...giving you almost the same torque as a 500 (the 490 has 4 ft/lbs less) but increases hp about 5hp above the modded but stock pistoned 500.. The 490 in this case had 14:1 compression and had to run race gas. Thumper is now telling me that with their 550 big bore kit for the 500, and an sx cam, with a 14:1 compression piston...they are hitting over 70 rwhp on the dyno...torque is almost 50 ft/lbs. All at the same 9650 rpm. Looks like we will be trying this combo next summer when tracks come off, and the supermoto wheels get reinstalled.

Just some rambling thoughts,

Chris

P.S. I am talking about the MY 2020 and 2021 motor here
 

CB-BLR

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Byeatts it’s pretty obvious your not a 500 fan!!! There is no need to insult guys with comments like “of course ewe (you) who have a 500 will never comprehend the facts about RPM which relates to track speed with a gearbox transmission”! I’m a guy who owns a 500 and I’m not ignorant to the differences between a 450 compared to a 500!
What an ignorant statement to make!
Just read my post above yours...lol
 

byeatts

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Just read my post above yours...lol
Interesting. I call things the way they are . I have both 450 and 500 here and if it was a contender i would ride it more.. Those who have this motor will justify their choice regardless of the facts. The problem with forums is riders get butt hurt if you dont tell them how great their machine is, Its quite comical on the mt running side by side seeing the difference in track speeds. Buy a 500 I care not, However others looking for truthful info to purchase the best bike for their riding style are grateful for factual info .
 

byeatts

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A few things to take into consideration here...You will never even get close to the potential of the 500 unless you mod or switch the throttle body to a 44mm like on the 450sx...this is worth 4-5 hp and 4-5 ft/lbs of torque...it also revs much quicker. Second point is that when dynoing both the stock PR2 and Raze ECU's on the dyno...after getting the unlock codes and appropriate cabling...we were able to get another 2-3 hp and ft/lbs by writing custom tunes for the bikes...and the rev limiter is raised to 10.5k so that the bike runs out of steam before hitting the rev limiter. I completely agree that both the 450sx and the 500 motors make almost the exact horsepower...the 500 at 9650 rpm, and the 450 at 11.1k rpm...but the 500 almost always is around 10 ft/lbs of torque up over the 450...and over a wider rpm range. Several companies are looking into trying the 450sx cams in the 500 to extend rpm without loosing that glorious torque...and a couple of other companies are looking at custom cams to do the same thing. Shortly here, I will be trying out the 450sx stator on the 500 as it is smaller and lighter. It does not put out enough juice to power lights and electric grips...but should let the 500 rev quicker. We shall see if that is a good thing or not. It should be noted that the 450xc has a stator that is more similar to the 500's than the 450sx.

On a side note...talking about the Thumper Racing 490 kit for the 450sx...it is wonderfully fun to ride...giving you almost the same torque as a 500 (the 490 has 4 ft/lbs less) but increases hp about 5hp above the modded but stock pistoned 500.. The 490 in this case had 14:1 compression and had to run race gas. Thumper is now telling me that with their 550 big bore kit for the 500, and an sx cam, with a 14:1 compression piston...they are hitting over 70 rwhp on the dyno...torque is almost 50 ft/lbs. All at the same 9650 rpm. Looks like we will be trying this combo next summer when tracks come off, and the supermoto wheels get reinstalled.

Just some rambling thoughts,

Chris

P.S. I am talking about the MY 2020 and 2021 motor here
The shorter stroke on the 490 kit seems promising since its capable of maintaining the 450 motor RPM. good info Chris.
 

CB-BLR

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Interesting. I call things the way they are . I have both 450 and 500 here and if it was a contender i would ride it more.. Those who have this motor will justify their choice regardless of the facts. The problem with forums is riders get butt hurt if you dont tell them how great their machine is, Its quite comical on the mt running side by side seeing the difference in track speeds. Buy a 500 I care not, However others looking for truthful info to purchase the best bike for their riding style are grateful for factual info .

I have both a 2018 450xc and a 2020 500 xc-f. Both modded...With me weighing 245 stepping out of the shower... And the extra traction of an ARO 3... In the Pacific NW wet and heavy snow...I prefer my 500. My 150 lb son likes the 450 on the 120 MH.

I didn't like the 450 on the Aro 3 for me... But then I also drive a 3500hd diesel truck.

It's all perspective.


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byeatts

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The video's above are predictable and silly.

The 500 has reeds in the intake for sound suppression, a 42mm throttle body, all of the smog stuff in place, and an exhaust that is restricted with several layers of physical blockage to reduce sound...along with an ecu programmed to meet California emissions.

The 450sx on the other hand has an open intake, a 44mm throttle body, no smog stuff, and an open exhaust...along with an ecu that is full tilt boogie from the factory and is not required to meet emissions.

on the 500...When you open up the intake by replacing the stock one with one off of an 450sx, either replace the throttle body with an 44mm off of an 450sx or have the stock one bored to 44mm, remove all the smog stuff so that it is like the 450sx, add a 450sx muffler or equivalent, and retune the ecu to similar specs as the 450sx (correct jetting for the 500) The 500 will make similar hp as a 450sx with a retuned ecu, and about 10 more ft/lbs of torque over a wider range...all at an approx 1500 rpm lower redline...while using slightly less fuel due to engine efficiency...and having a longer rebuild interval due to less stress on the recreprocating assembly and lower rpm.

Don't get me wrong...I love me a 450sx turned into a 490...but the greater torque of the 500 is easier to ride with an ARO 3 or heavier rider in my opinion.

The video's above are not representative of a level playing field.

Chris
Yes I have a 500 XCW as well here and fully un corked with ECU and full exhaust .It dynos at almost the same HP as the new SX 450 with a more torque down low . Riding side by side The 500 is extremely annoying to ride as it his the rev limiter 100 times a day , Again HP is not everything, RPM spins the track much faster and the extra 2000 RPM the 450 spins at is what makes the difference., The 500 is for sale, owner after the season has rode both and We are building a 450 for him. The Aro 3 runs at lower rpm, That track drags down RPM in exchange for grip . Great kits with different approach. Guys we run these side by side over and over, The results are fabricated they are documented.These forums are for info and discussion, The arrogant comments are just that from internet know it alls, We have been building Mountain race sled motors and bikes since 2001 and have them all over the country, We dyno and tune and Simply put HP is not the tell all, Its simply a part of the package. Agreed the 500 is very easy to ride especially for beginners since it can be lugged all day,For advanced riders the RPM is simply annoying.
 

CB-BLR

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Yes I have a 500 XCW as well here and fully un corked with ECU and full exhaust .It dynos at almost the same HP as the new SX 450 with a more torque down low . Riding side by side The 500 is extremely annoying to ride as it his the rev limiter 100 times a day , Again HP is not everything, RPM spins the track much faster and the extra 2000 RPM the 450 spins at is what makes the difference., The 500 is for sale, owner after the season has rode both and We are building a 450 for him. The Aro 3 runs at lower rpm, That track drags down RPM in exchange for grip . Great kits with different approach. Guys we run these side by side over and over, The results are fabricated they are documented.These forums are for info and discussion, The arrogant comments are just that from internet know it alls, We have been building Mountain race sled motors and bikes since 2001 and have them all over the country, We dyno and tune and Simply put HP is not the tell all, Its simply a part of the package. Agreed the 500 is very easy to ride especially for beginners since it can be lugged all day,For advanced riders the RPM is simply annoying.

Yup... Unless you get that tiny 42mm throttle body off of the 500... It will never rev out. They put a 44mm on the 450... The 42mm on the 500 is choking it on the top end. I went to a 44mm on the 500 and it picked up both torque and hp...To the tune of 4 each. Put on a 46mm throttle body and it picked up another 2 hp and 1.5 ft/lbs of tq. Peak hp is now at 10.1 k Limiter at 11k. Going to be trying a billet 47 and 50mm throttle body next on the Dyno along with a bigger intake and exhaust. Is the mountain testing you are doing on a 20 or 21 500? 20 was when they changed to the better flowing 450sx head... And they flat out pull harder and longer than previous years.

Just my experience.

P.S. I never hit the Rev limiter now on the 500... And if I did...I would gear the kit up to take advantage of the 500's superior torque... Thus also increasing track speed.

It is all just personal preference and set up in the end.


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byeatts

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Yup... Unless you get that tiny 42mm throttle body off of the 500... It will never rev out. They put a 44mm on the 450... The 42mm on the 500 is choking it on the top end. I went to a 44mm on the 500 and it picked up both torque and hp...To the tune of 4 each. Put on a 46mm throttle body and it picked up another 2 hp and 1.5 ft/lbs of tq. Peak hp is now at 10.1 k Limiter at 11k. Going to be trying a billet 47 and 50mm throttle body next on the Dyno along with a bigger intake and exhaust. Is the mountain testing you are doing on a 20 or 21 500? 20 was when they changed to the better flowing 450sx head... And they flat out pull harder and longer than previous years.

Just my experience.

P.S. I never hit the Rev limiter now on the 500... And if I did...I would gear the kit up to take advantage of the 500's superior torque... Thus also increasing track speed.

It is all just personal preference and set up in the end.


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I have a 2015 XCW with PR2 throttle body and full exhaust and ECU and a 2021 xcw stock throttle body.
 

CB-BLR

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I have a 2015 XCW with PR2 throttle body and full exhaust and ECU and a 2021 xcw stock throttle body.
I would recommend going straight to the PR2 46mm throttle body mod for the 500.
and just for fun...First try putting the 42mm throttle body off of the 500 onto the 450 and let me know how it revs out...chuckle. =)

On a more serious note...I hope you have a great day sir!
 
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So I'm personally going through the same debate on a decade older motor. I'm building an rfs atv based bike to replace my raptor(gotta have reverse). ironically I'm dealing with the same bore and stroke options as you guys. My take is if I can make the 500(525) safely rev as high as the 450 and make equal peak power then the 500 will be better because of the torque. But the 5 will always cost more $ to get to same perf level and does anyone know if they have more crank problems with the longer stroke? You can tell me the 5 doesn't work as hard and will last longer but any proof? The 72mm rfs cranks needed to be welded to handle long term snow duty. I choose to do a 450sx base build for now because I like to rev and if I get another stimulus check I might consider a 525 crank or possibly big bore as long as it will still rev.. if it doesn't rev the 450 parts will go back in.
 

CB-BLR

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So I'm personally going through the same debate on a decade older motor. I'm building an rfs atv based bike to replace my raptor(gotta have reverse). ironically I'm dealing with the same bore and stroke options as you guys. My take is if I can make the 500(525) safely rev as high as the 450 and make equal peak power then the 500 will be better because of the torque. But the 5 will always cost more $ to get to same perf level and does anyone know if they have more crank problems with the longer stroke? You can tell me the 5 doesn't work as hard and will last longer but any proof? The 72mm rfs cranks needed to be welded to handle long term snow duty. I choose to do a 450sx base build for now because I like to rev and if I get another stimulus check I might consider a 525 crank or possibly big bore as long as it will still rev.. if it doesn't rev the 450 parts will go back in.
If quick revving is what you are after...a big bore on a 450 is the way to go. (a 14:1 compression 490) This combo with a ported 450 sx head on a RFS motor will sing for sure. I have been talking with Brock Buttars about putting a 450sx flywheel and stator on a 2021 500 to help it rev quicker. The 490 will not have as much torque...or as wide a torque powerband as a 500...but it will rev to the moon.
 

byeatts

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If quick revving is what you are after...a big bore on a 450 is the way to go. (a 14:1 compression 490) This combo with a ported 450 sx head on a RFS motor will sing for sure. I have been talking with Brock Buttars about putting a 450sx flywheel and stator on a 2021 500 to help it rev quicker. The 490 will not have as much torque...or as wide a torque powerband as a 500...but it will rev to the moon.
yes agreed .The 490 BB maintains the same stroke as the 450 and Revs very high, No matter what you do physics will not allow a 500 to spin even close to the 450, RPM equals track speed
 
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