450 Bike Hours

Solidkm
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382
Joined
4/6/2018
Location
Aurora, CO US

Hey guys, looking to hear some of your experiences regarding higher engine hours 

Currently on a 21 Gas Gas 450 which I use for motocross - mostly practice sessions, I don’t race a lot. And I don’t float the valves trying to be cool. 

Bike has 125 hours on it. I did a top end/ timing chain at 95. Bike is well maintained, valves in spec, oil every 4 hours, etc

Bike is great, I have no issues whatsoever, and am hesitant to replace it bc it works so well for me. That said, I have not kept one this long before and I have it in my head that its  gonna grenade on me on a jump face.  I understand anything can happen at any time, but my question is it simply in my head? Is it reasonable to expect the engine to be trouble free at 120-200 hours? What experiences have you guys had?


Thank you 

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captmoto
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5799
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4/22/2009
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Rancho Cucamonga, CA US
9/7/2025 5:19pm

It's in your head. Did you do the crank and main bearings? I think 100 hours is where KTM/HUS/GASGAS recommends a full rebuild.

Solidkm
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382
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4/6/2018
Location
Aurora, CO US
9/7/2025 5:38pm

I did not do a crank or main bearings. I did check the rod play and it was in spec 

chasetwo79
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1562
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12/1/2019
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Truckee, CA, CA US
9/7/2025 5:46pm

You're fine. Around 150 just rebuild everything and it'll get you another 150-200 hours. 

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O&GDriller
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Chattanooga, TN US
9/7/2025 6:19pm Edited Date/Time 9/7/2025 6:21pm

My son and I have bought/ridden eight new KTM‘s since 2010. We put well over 200 hours on each of them without ever opening up an engine. I’m old and slow, however, he’s a B . They just keep going. I took one up to 264 hours before I updated. 

We change oil every 10 hours and that’s it. 

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1

The Shop

Solidkm
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382
Joined
4/6/2018
Location
Aurora, CO US
9/7/2025 6:29pm

Thank you guys for the comments!

mx510
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1992
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2/26/2011
Location
Gig Harbor, WA US
9/7/2025 7:21pm
Solidkm wrote:
Hey guys, looking to hear some of your experiences regarding higher engine hours Currently on a 21 Gas Gas 450 which I use for motocross - mostly...

Hey guys, looking to hear some of your experiences regarding higher engine hours 

Currently on a 21 Gas Gas 450 which I use for motocross - mostly practice sessions, I don’t race a lot. And I don’t float the valves trying to be cool. 

Bike has 125 hours on it. I did a top end/ timing chain at 95. Bike is well maintained, valves in spec, oil every 4 hours, etc

Bike is great, I have no issues whatsoever, and am hesitant to replace it bc it works so well for me. That said, I have not kept one this long before and I have it in my head that its  gonna grenade on me on a jump face.  I understand anything can happen at any time, but my question is it simply in my head? Is it reasonable to expect the engine to be trouble free at 120-200 hours? What experiences have you guys had?


Thank you 

One of my good friends has a 2018 KTM 350 with 280 hours. If you keep clean air filters and don’t suck dirt as well as replace parts when needed including doing regular oil changes you are probably fine IMO. I am a Yamaha guy, but I have seen some SUPER high hour KTMs just keep on trucking. 

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DF313
Posts
696
Joined
6/17/2016
Location
Ogden, UT US
9/7/2025 7:38pm Edited Date/Time 9/7/2025 7:38pm

2017 KTM 350 272.7 hours. Still on the original crank bearings, everything else was done at 230 hours.  Runs great, I really enjoy the bike. 

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Solidkm
Posts
382
Joined
4/6/2018
Location
Aurora, CO US
9/7/2025 7:39pm

I take care of the air filter and oil for sure. Not especially hard on equipment. KTM has been good to me 

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bingerfang
Posts
59
Joined
1/24/2019
Location
La Habra, CA US
9/7/2025 8:31pm

I had 320 hours on my 2017 Husqvarna 450. Zero issues, never changed anything but the oil.

1
aees
Posts
2635
Joined
8/20/2015
Location
US
9/8/2025 4:42am

I have over 220h on one of my austrian 450, 19-22 generation. Just done pistons at 55-75h. Camchains wasn't even possible to measure the stretch. No valve shim required. MX only, pretty fast pace so not just round around.

I have pros I know who put 400h into bottomend on 250 Enduros.

Own thing I would go over, is cables behind numberplate and down to injector etc. If any issues, that's the ones. They dry out and get rubbed by dirt.

Cut all open, and use vulcanised tape or shrinking tape lathe way onto the connectors. Also replaces filter inside fuel tank proactively. 

Fuel lines brake, wires gets worn off, or worst case frame cracks with high hours if you do moto and launches big jumps. But 19-22 frame much better, 16-18 was almost guaranteed issue with when ridden hard moto.

Oh, and replace all bolts. Specially sub frame ones but all of them is subject to wear. I replaced the smaller ones every 100h. Frame bolts every 75h.

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30minmotos
Posts
700
Joined
8/7/2025
Location
Rising Sun , MD US
9/8/2025 4:55am

Personally, if you have the discipline to do this and not stray from the plan.


Sell that for 4k and buy one with 2-10 hours on it for 45-5k makes more practical sense to me. And before you say the numbers aren’t accurate: they’re realistic based on my friends and I experience, maybe locally yours are higher or lower but it’s all relative.


 

9/8/2025 10:37am

had an 08 yamaha and put over 300 hard hours on it with only changing oil and air filter once in a while

skeef
Posts
1435
Joined
7/18/2018
Location
AZ US
Fantasy
9/8/2025 10:49am

had an 08 yamaha and put over 300 hard hours on it with only changing oil and air filter once in a while

I had an 09' yz450 with 350 hard dez hours. oil and oil filter every 5-7 hours, checked timing every 50 hours. I think I adjusted it once. 

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