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
Chris
ktm 500 vs 450
- Thread starter cisco
- Start date
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
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 .
The shorter stroke on the 490 kit seems promising since its capable of maintaining the 450 motor RPM. good info Chris.
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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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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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!
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.
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
I have done many upgrades a tuning to the 500,s. The kicker is the limitation of the 500 long stroke engine, The RPM,s and over rev is Much lower than a stock 450 race engine that spins to the moon., RMP equates to track speed, Torque and HP low in RPM range does not spin the track fast ,And yes the 500 gearing is horrible and require a SX gear change, When you do all the engine mods like cams ect like ewe suggest on the 450 engine is raises the bar considerably. stock vs stock there is no comparison.
Stock vs Stock...I would agree that the 450sx is more potent than the 500 xcf-w
But bolt on to bolt on...The 500 improves a lot...while the 450 improves a little.
I agree with the video's attached above showing the dyno runs of both bikes stock...and found similar results.
The 450 had peak hp at about 9300 rpm.
I have attached the dyno sheet of my previous 2020 500 with bolt ons...as you can see peak hp is at slightly over 9k, and revs until over 10 k. The rev limiter is at 11k...which it never hits. It is basically in the same rpm range as the 450...just pulls harder.
I am working on a 550 at this point.
Have fun out there!
But bolt on to bolt on...The 500 improves a lot...while the 450 improves a little.
I agree with the video's attached above showing the dyno runs of both bikes stock...and found similar results.
The 450 had peak hp at about 9300 rpm.
I have attached the dyno sheet of my previous 2020 500 with bolt ons...as you can see peak hp is at slightly over 9k, and revs until over 10 k. The rev limiter is at 11k...which it never hits. It is basically in the same rpm range as the 450...just pulls harder.
I am working on a 550 at this point.
Have fun out there!
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Quote: "I have done many upgrades a tuning to the 500,s. The kicker is the limitation of the 500 long stroke engine, The RPM,s and over rev is Much lower than a stock 450 race engine that spins to the moon., RMP equates to track speed, Torque and HP low in RPM range does not spin the track fast ,And yes the 500 gearing is horrible and require a SX gear change, When you do all the engine mods like cams ect like ewe suggest on the 450 engine is raises the bar considerably. stock vs stock there is no comparison."
Another thing to consider here...as I have talked about before...is the kit type and the rider weight. Talking about track speed with an ARO 3 track is just silly...you are not going to get much track speed with a 3 inch lug. Most motorcycle motors just don't produce enough torque to spin this traction monster. Even Polaris engineers recognized this and geared down the 3 inch kits by approximately 10% because they were so hard to spin. Track speed with a 120 2.5 lug or even shorter lug...and maybe even a 129 track with a tapered lug can have a discussion of track speed. Heavier riders also need as much torque as possible. I have not gotten the set up dialed in yet on the dyno for my 550...not even tuned completely yet...or with the correct intake and throttle body...it is making north of 45 ft/lbs of torque and 65 hp at 9k rpm. Should be glorious fun on the new Riot 3s kit!
In the end it is all about rider weight, snow conditions, bike to kit functionality...and having fun!
Have fun out there!
Another thing to consider here...as I have talked about before...is the kit type and the rider weight. Talking about track speed with an ARO 3 track is just silly...you are not going to get much track speed with a 3 inch lug. Most motorcycle motors just don't produce enough torque to spin this traction monster. Even Polaris engineers recognized this and geared down the 3 inch kits by approximately 10% because they were so hard to spin. Track speed with a 120 2.5 lug or even shorter lug...and maybe even a 129 track with a tapered lug can have a discussion of track speed. Heavier riders also need as much torque as possible. I have not gotten the set up dialed in yet on the dyno for my 550...not even tuned completely yet...or with the correct intake and throttle body...it is making north of 45 ft/lbs of torque and 65 hp at 9k rpm. Should be glorious fun on the new Riot 3s kit!
In the end it is all about rider weight, snow conditions, bike to kit functionality...and having fun!
Have fun out there!
Built Motors...the machinist that took over Thumper Racing. (He has been doing this type of work for years) I will check the piston manufacturer...but it is a big bore for the current generation 500's. They set up the piston to wall clearances which I double checked. Compression is 14:1. I am also trying the 450sx cam. Hp is only about 5 above the stock bore at 9200 rpm...but up 8 hp at 8k rpm...the motor is tapering off sooner...but still easily revs to 10k. I am going to be trying a bigger throttle body, and some different cams to see if we can eak out some more on the top end without taking away from the bottom/mid. Torque is 5-6 ft/lbs above the 500 everywhere. My last iteration of the 500 had a thinner base and head gasket that brought the compression up from 12.75 to about 13.4...but the 550 is still stronger. I am also testing various intake lengths which were generously provided by AirForce...to see what the 550 likes on the Dyno.
With all the motor work weve done I maintain that high RPM is far better than just HP on the snow with a transmission ,that extra 10mph track speed / 12000 rpm is golden on the 450sx. we do have lots of air at 5K feet and motor spools quickly ,lower rpm does not spin the track fast and upshifting under full load difficult . Perhaps at high elevation the Torque game changes where motor starves for air.