One of the reasons I got into snowbikeing was that I was sick of blowing up polaris's and cats eating belts, and oil, and fuel and all that crap. Am I living in a fantasy world thinking the bikes will be more reliable. I have a 2013 ktm 450sx with a 2015 long track and I am loving it. I really don't feel like I'm revving the piss out of it, but when your climbing in those trees in def keeping that thing pegged in 1st. So what's been your experience with good maintenance?
4 stroke reliability-let's hear what's going on with your bikes
- Thread starter Andrewcoutavas
- Start date
I'm on my 3rd season on a KTM500XCW, and it's never been opened up, and works as it's intended to.
I'll probably either freshen it up or flip it for next year, but 3 years is not uncommon if you use good oil and change it often.
I had a KX450 for 3 seasons as well, that was a rental bike.. It never missed a beat in the 3 snowbike seasons I had it for as well.
Jon
I'll probably either freshen it up or flip it for next year, but 3 years is not uncommon if you use good oil and change it often.
I had a KX450 for 3 seasons as well, that was a rental bike.. It never missed a beat in the 3 snowbike seasons I had it for as well.
Jon
Thanks for the info I was gonna actually message you because i knew you had the same bike. I always appreciate all your help in this forum. It's nice having people in this new sport that can help.
My 650 is toast. The primary gear chipped off, contaminated the oil, the crank broke and the piston went into the valves.
I changed oil before that ride, put on about 80km and I even made it home when it died.
It cost me about $800 to tear down, I though it might have been just a gear broke when kicking it over. To fix the engine it was going to be $6600.
I changed oil before that ride, put on about 80km and I even made it home when it died.
It cost me about $800 to tear down, I though it might have been just a gear broke when kicking it over. To fix the engine it was going to be $6600.
Ktm 450 blew the valves out season 1, rebuilt it as a 520 after about 80 hours on the brand new motor season 2 the also brand new KTM con rod dropped a bearing. KTM wouldn't warranty the rod but they did sell me a new one at cost.
Total cost of that whole episode about $3500.00. Now the bike is back to dirt only no more snowbiking with it. On a CR500 now.
M5
Total cost of that whole episode about $3500.00. Now the bike is back to dirt only no more snowbiking with it. On a CR500 now.
M5
I think a lot of guys getting into this sport dont understand the maintenance required on these motors especially the motocross bikes. When I raced them I changed oil every ride day, checked valves at 25 hours and at 50 it was time for a teardown. I might be a bit over the top but these things are getting workout with these track kits, over fueling in the cold and running high RPM's consistently there going to need lots of love to live. Granted that's why I run 300 in the summer and now in the winter, got tired of the maintenance.
I bought a 2011 KX450F with 30 race hours on it. I rode it for another 30hrs in the sand dunes. Then put a 2014 Timbersled ST kit on and rode 65 days last winter. Bike had 495 hours on it without a rebuild. I changed oil every ride whether is was 2 or 10 hours- no questions asked. Pulled the engine apart this spring, and it looked pretty nice. The piston was replaced, and the bike is still running to this day.
No joke. Do your maintenance!!!!
No joke. Do your maintenance!!!!
I hear nothing but great things about the kawis, only thing they need is a button!
2014 ktm sxf 450. Less than 40 hours total (25 on the snow).
Started making an odd noise on the trail out last ride. Checked it out and discovered the Intake Rocker arm had failed causing one of the intake valve shims to fall out of retainer. Also now need to replace the camshaft as its grooved.
Not sure why the rocker arm failed. Recommend checking if you are on the same bike.
Pricey fix. Not worst case scenario but still a drag. Not what I was expecting from the new ktm.
Back to the 300 2stroke until this motor is fixed!
Started making an odd noise on the trail out last ride. Checked it out and discovered the Intake Rocker arm had failed causing one of the intake valve shims to fall out of retainer. Also now need to replace the camshaft as its grooved.
Not sure why the rocker arm failed. Recommend checking if you are on the same bike.
Pricey fix. Not worst case scenario but still a drag. Not what I was expecting from the new ktm.
Back to the 300 2stroke until this motor is fixed!
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PalousePoo
Well-known member
, but when your climbing in those trees in def keeping that thing pegged in 1st. So what's been your experience with good maintenance?[/QUOTE]
A little off topic, but my YZ or SXF wont climb worth a darn in 1st gear! Too slow, too much track spin. 2nd has plenty of power. Both have ST kits.
2011 YZ 450, 210 hours, valves never shimmed and still in spec at 190 hours when checked. Leakdown only 4% more than a new broke in eng. Oil changed every 3 rides, approx 10-15 hrs.
2015 KTM SXF, 40 hrs, no problems
A little off topic, but my YZ or SXF wont climb worth a darn in 1st gear! Too slow, too much track spin. 2nd has plenty of power. Both have ST kits.
2011 YZ 450, 210 hours, valves never shimmed and still in spec at 190 hours when checked. Leakdown only 4% more than a new broke in eng. Oil changed every 3 rides, approx 10-15 hrs.
2015 KTM SXF, 40 hrs, no problems
I've thought a lot about this and the only thing I can come up with it the extended high rpms is frothing the oil to a point where it doesn't get pumped very well. I changed my oil religiously using Motorex as recommended by KTM as in like $80.00 a gallon oil. The XC4 motor had a rocker shaft update to increase the oil to the rockers which has followed the engines through the years but the design can only support so much flow. I had every oiling update possible done to my motor new larger oil pump gears, rockers modded, new oil passages added, single sump conversion, larger oil jet etc etc. Its the rpms plain and simple. If you cruise around all day it'll last forever but if you push it real hard its going to blow up. I think the Japanese bike are tougher than the euro bikes JMO. My motor let go both times on long pulls on the rev limiter. The first time when it took out a valve at the top of the pull it was smoking like a 2 stroke. The second time was a huge day in the spring where I was on it for hours rod let go. I would NEVER buy a used 4 stroke that I knew had been snow biked or been to the dunes.
M5
2012 KX450
Hey there...I wanted to get into snow biking so I sold my 2013 pro rmk and bought a used 2012 Kx450 with 30 hrs. on it...snow checked a 2015 ST kit...while waiting for it to arrive I rode 3 or 4 times on the mx track...put the kit on and rode for 3 days...I broke the ratchet gear on the kick start...started making this god awful grinding noise...the tip of the ratchet fell down in behind the clutch basket and then got spit out and broke both the inner and outer clutch covers. Limped it back to the trailer...now I have it all fixed up but have not had a chance to get back out...anyone else ever have this happen? Or why this would have happened? Oil changed every ride valves checked every 15 hours still in spec..only have 47 hours on the bike.
Hey there...I wanted to get into snow biking so I sold my 2013 pro rmk and bought a used 2012 Kx450 with 30 hrs. on it...snow checked a 2015 ST kit...while waiting for it to arrive I rode 3 or 4 times on the mx track...put the kit on and rode for 3 days...I broke the ratchet gear on the kick start...started making this god awful grinding noise...the tip of the ratchet fell down in behind the clutch basket and then got spit out and broke both the inner and outer clutch covers. Limped it back to the trailer...now I have it all fixed up but have not had a chance to get back out...anyone else ever have this happen? Or why this would have happened? Oil changed every ride valves checked every 15 hours still in spec..only have 47 hours on the bike.
Not doubting you... Just wondering if this is actual metered hours or an estimation based on days of riding? Either way that's impressive!
R
Rush44
Well-known member
M5 has had the worst time with a 4 stroke out of anyone I've met in 4 years of snowbiking. I think sometimes you just get a lemon and you're kinda screwed no matter what you do. We have some guys who blow them up and we have some guys who have 300+ hours and the motor looks new inside. There is a camp out there that believes snowbiking is BETTER on a motor than traditional summer only dirt and desert riding (and I can see their point).
It's impossible to say who is right. This weekend we had a Skidoo blow up. Last week a new Pro RMK that tagged along blew up. Motors explode sometimes and at this point I'm not seeing anymore failures than I saw during the snowmobile days. We used to tow in motors to swap on the hillside and now we call choppers on the regular. I don't think anything has changed.
It's impossible to say who is right. This weekend we had a Skidoo blow up. Last week a new Pro RMK that tagged along blew up. Motors explode sometimes and at this point I'm not seeing anymore failures than I saw during the snowmobile days. We used to tow in motors to swap on the hillside and now we call choppers on the regular. I don't think anything has changed.
M
mxracer299
Well-known member
Some last some dont, 2 stroke or 4 stroke doesn't really matter, they all have a limited life span with how we are treating them. It would be the equivalent of taking your truck with a trailer hooked to it and putting it on the rev limiter while pulling a hill for hours on end, how many trucks would last 100hrs like that? Just driving normal it would easily go 100,000 miles.... Its same same with bikes, the more you bounce them off the rev limiter the more you wear your engine, put around and they will last forever. The lower revving 500 engines seem to be lasting longer than the 450s, I would assume its just from turning lower rpms. All of the engines are designed to run high rpms for SHORT amounts of time so the way we ride them is going to be hard on them and whatever weak points there are in the motor are going to give up first which is why its impossible to determine exactly how long a motor is going to last, there are flaws in every motor. Frankly I'm highly impressed these motors last as long as they do, they are all very well designed motors!
IMO you're right on the money. I don't have any delusions of my CR500 lasting any better, it's just that it won't cost me $3k to redo the top end. The big 2 strokes mostly don't pull over 8k where the 4t is like 11,500 rpm with lots of moving parts, some might argue too many.
M5
M5
I will chime in, to me you look at it blowing up a single cylinder will always be cheaper than blowing up a double or triple cylinder.. to me all these engines are tuned to the ragged edge... maintaining them helps a lot but sometimes things just fail.... I am on the 2 stroke boat because at least when it grenades it's a lot less money....
