ktm 500 vs 450

CB-BLR

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1638410056799.jpeg
And this is where I am at with my 550 after going and playing with Lloyds Performance.

This is on 92 oct pump gas.
We got this number on both David Lloyds dyno in Idaho, and 2-wheel DynoWerks in Kirkland Wa.

On both Dynos we hit 75.5 hp by adding a bit of MR12 to the tank...but I thought it was more fair to post an equal comparison on pump fuel..

Chris
 

CB-BLR

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Yah that what riding a 500 on the snow is like , It kills the track speed, The 450 never taps the limiter and pulls another 2500 rpm over the 500.
Hog Wash!!! 750-1000 rpm difference due to the rev limiter on the 500 being set at 10.2k and the 450 being set at 11.2k.
With both rev limiters being set the same...they both like about 10.5k before they both start falling off quickly. You guys must be talking about the previous generation of 500's. (Note: the stock 42mm throttle body on the 500 makes it feel sluggish on the top end...but it still pulls the rpm.)
 
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CB-BLR

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Side note: the head pipe on the 500 is too big. Switching it over to a head pipe from a 450 SX really helps with over-rev. I like the full 450 SX pipe from RP race the best. (tested several combo's), with the Yoshi system being a very close second.
 

dooman92

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Wow, 74 hp that has to be better than expected? 550, air force velocity, vortex and exhaust? Should kick azz on the snow...
That has 14.1 compression piston correct?
 
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CB-BLR

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Wow, 74 hp that has to be better than expected? 550, air force velocity, vortex and exhaust? Should kick azz on the snow...
Built Motors 550 big bore kit with 14:1 piston
47mm RP Race Throttle Body.
Air-Force intake
Intake, intake boot, and head ported by Lloyds performance
Lloyd Performance cam
RP race 450sx complete exhaust
Vortex ECU programed by 2-Wheel Dyno-Werks.
GET ECU programed by Lloyd Performance.

Both ECU's produced the same results
Both the dyno in Idaho and the one in Washington showed nearly identical results on the same fuel.

Definitely better than expected!

Thank you to David, Karson, and Nels for help on this combo.

I am done for now...but have plans for a bigger throttle body, a fully balanced rotating assembly, and a more aggressive cam for next season.
 

byeatts

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Hog Wash!!! 750-1000 rpm difference due to the rev limiter on the 500 being set at 10.2k and the 450 being set at 11.2k.
With both rev limiters being set the same...they both like about 10.5k before they both start falling off quickly. You guys must be talking about the previous generation of 500's. (Note: the stock 42mm throttle body on the 500 makes it feel sluggish on the top end...but it still pulls the rpm.)
Geeze the longer stroke motor Will not run even close to the same RPM as the 450 , Have them both . The 500 runs at a much lower RPM and hits rev limiter all day long, Its a grunt motor and makes its power down low, a modded motor does alter the rpms, The same mods on a 450 will always runs more RPM, simple Physics of a shorter stroke.
 

CB-BLR

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Geeze the longer stroke motor Will not run even close to the same RPM as the 450 , Have them both . The 500 runs at a much lower RPM and hits rev limiter all day long, Its a grunt motor and makes its power down low, a modded motor does alter the rpms, The same mods on a 450 will always runs more RPM, simple Physics of a shorter stroke.
Just replying to the 2500 rpm peak hp difference between the 450sx and the 500 xcf-w both with the same exact intake and exhaust tracks...is negligible.
Sorry I was being so feisty last night. :(
 

cbc76am

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Big bore on a 450 is the way to go... get all the rpm, and better gearing and get the lug to carry 3rd gear better,.. I stop at 500 but wouldn't be against the 550 or the 588 kit that raze does. Just gotta have the right shop do the flow bench porting, over sized valves, and map to really get the most out of it. Even with just a 500 kit, stage 2 cams, and a pipe on the old yz450 it is a completely different motor - way better everywhere. GYTR head and your in business.

I don't do KTMs on the snow anymore... got passed on too many climbs by blue bikes.
 

CB-BLR

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Big bore on a 450 is the way to go... get all the rpm, and better gearing and get the lug to carry 3rd gear better,.. I stop at 500 but wouldn't be against the 550 or the 588 kit that raze does. Just gotta have the right shop do the flow bench porting, over sized valves, and map to really get the most out of it. Even with just a 500 kit, stage 2 cams, and a pipe on the old yz450 it is a completely different motor - way better everywhere. GYTR head and your in business.

I don't do KTMs on the snow anymore... got passed on too many climbs by blue bikes.
I sincerely would love to see some dyno sheets of a built yz motor.

Chris
 
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This is some very impressive numbers on these KTM's! I'm going to be building one this summer.

BTW, I have seen Geisick Performance is selling bigger injectors for these KTM, Huskie, and Gas Gas bikes. Not sure if i can post the links but should be able to handle any amount of power you could make or even if you wanted to run e85. They also have a big bore cylinder and piston coming out that should be much more reasonable in cost and a much stronger design.

Has anyone tried simply running a Dynojet power commander instead of these vortex and GET ecu's? thats what i have always used in the past and they worked great, and way easier to tune. could even add the auto tune to monitor how the engine is running and get things dialed in better.
 

byeatts

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Track speed is all about RPM when running a gearbox , Look at the RPM of the 500. Very low in comparison to a 450,with 4-8 mPh track speed differences in same gear. The 500 we have here is pumped up , intake ,exhaust ECU high compression and the perfectly tuned 450 will destroy it,I will take a motor that runs high rpm over HP., The 500 requires short shifting and has little overrev and hit rev limiter all day.I agree different riding terrain could warrant different preferred motors .
 

madmax

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How many hours on a 450 or 500 ktm before you have to worry about the motor not holding up on the snow?
 

GKR

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I have done top ends on alot of 150hr motors that were totally in spec and probably good for more. Heads seem to hold up well, pistons are probably the area of concern with hours in my opinion. Bottom ends seem to be good for plenty more if oil is changed. Snowbike environment is super clean so you are likely to fatigue parts before you are forced to overhaul do to contamination wear which is much more significant in summer. (As long as you are keeping your temps up and keeping moisture out of your oil. )
If you are not wringing out the motor all day long I would suggest you could stretch to more hours and you will hear many guys who said they made it to 300 and beyond.
In a snowbike, at least where I am riding, you don’t want to have a failure if you can help it so I suggest in the 150-200 hour max for a top end anyway. I would suggest a leakdown test at 100hrs and then again at 125-150 and see what you can learn from the results.
Lots of debate on this subject but this is my experience.
 
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A chopper ride more than covers the cost of top end parts so failure is not an option so I do the top end in the off season around 100 hours just depending on how it works out. The 500's seem to really last a long time I know guys with more than 250 hours on them but I find them kind of cumbersome to ride. I'm not sure why but they just seem bulky to me for no good or logical reason kind of like 500=diesel and 450=sports car.

M5
 

byeatts

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HP is Not the tell all, RPM is what creates track speed and the 500 regardless what you do physically cannot match the shorter stroke and RPM of the 450. I have fully built 500,s and the motors are limited in the RPM department, Its easier for new riders and better if you wish to run it in the dirt. there are limitations with a long stroke engine ,the same applies to a 2 stroke which have similar RPM,s to the 500.
 
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