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main bearing failures on '12-16 KTM 250-300s

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There is a big thread on KTMTalk about main bearing failures on said years of 250 and  300s. Something about the quality of the bearings KTM used in those bikes. Most people have said about roughly 250 hours before the bottom end goes out and have to get bottom end rebuilt. Anyone here of these issues on this forum. I have a 2016 KTM 250XCW with about 40 plus hours on it and don't really want to rebuild at 250 hours. Went over 11 years on my '02 KTM 300EXC before I sold it and as far as I know it is still going strong. Maybe there are other issues with said bikes like maybe lack of maint. like air filter cleaning , proper jetting, drowning the bike and so forth. I take care of bike pretty good, just hoping I did not get a bike with bad main bearings. Yikes!

Little Jeff

Edited by Little Jeff

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My 13 lost the clutch side crank seal at about 289hrs. put a new one in bearing seemed fine. At over 400 hrs it toast again. It's parked no catostrophic fail, runs fine. Original piston looked like sht at 300hrs, don't let it go that long mine showed slight stress cracks at the skirt.

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I think, god forbid if this ever happened to my bike, I would pull the motor and send the bottom end of motor to Mr Cooksy of Cooksey Cranks down in Texas

Jeff

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At over 100 hours on a race bike that only holds a quart of oil your pushing your luck. These aren't TTR/XRs guys. You could push 200 just trail riding but I wouldn't go any more than that.

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250 hours and people are complaining?

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26 minutes ago, markit said:

At over 100 hours on a race bike that only holds a quart of oil your pushing your luck. These aren't TTR/XRs guys. You could push 200 just trail riding but I wouldn't go any more than that.

?? He is talking about a two stroke so that quart of oil ( actually 750cc) is for the transmission only.

 

Joe

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7 minutes ago, DEMI said:

250 hours and people are complaining?

On a bottom end, not top.......yes 250 would be way too early. I run 200 or more a year on my bikes.

 

Joe

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13 hours ago, Little Jeff said:

There is a big thread on KTMTalk about main bearing failures on said years of 250 and  300s. Something about the quality of the bearings KTM used in those bikes. Most people have said about roughly 250 hours before the bottom end goes out and have to get bottom end rebuilt. Anyone here of these issues on this forum. I have a 2016 KTM 250XCW with about 40 plus hours on it and don't really want to rebuild at 250 hours. Went over 11 years on my '02 KTM 300EXC before I sold it and as far as I know it is still going strong. Maybe there are other issues with said bikes like maybe lack of maint. like air filter cleaning , proper jetting, drowning the bike and so forth. I take care of bike pretty good, just hoping I did not get a bike with bad main bearings. Yikes!

Little Jeff

Jeff, my '12 bike had over 700-800 hours when I sold it and never had bottom end issues at all.

 

Joe

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On my old jap bikes 125 I would only expect 50 hours lol

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3 hours ago, trailmeisterjoe said:

?? He is talking about a two stroke so that quart of oil ( actually 750cc) is for the transmission only.

I have no idea what the OP is talking about. Usually "bottom end" bearings are about the big end bearing on the con rods and the crank bearings right next to them. Getting 200 hours out of those sounds fine to me.

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3 hours ago, trailmeisterjoe said:

?? He is talking about a two stroke so that quart of oil ( actually 750cc) is for the transmission only.

 

Joe

My bad, but still 200 hrs on a crank is stretching it. Get a manual and see what the service intervals are. Anything beyond that is on the user. Anyone that trail rides a race bike needs to understand that there not using it in it's true form and it's never going to be a trail bike, it's a race bike and has to be treated as such. The cranks are failing because there well out of the service range. I can totally understand the lure of having the tip of the sward to ride in the woods but you have to understand the choice they have made, and as I said before if you want a TTR or XR trail bike get one nothing at all wrong with that but a KTM race bike isn't going to be a 200 hr none maintenance bike. This is why KTM gets so much grief,  wrong tool for the wrong job, If you get a Lambo to commute to work don't complain about the fuel mileage and  low seat hight.:smashpc::devil: 

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4 minutes ago, Scottwr12345 said:

500 + on my yz 250 lol

get outa here, this is KTM land.

My old TZs would get no more than about 20 hours, it was the price of racing.

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Just now, pat22043 said:

get outa here, this is KTM land.

My old TZs would get no more than about 20 hours, it was the price of racing.

Haha fear not my ktm loving friend, im days away from picking up my ktm built te250!!

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1 minute ago, Scottwr12345 said:

Haha fear not my ktm loving friend, im days away from picking up my ktm built te250!!

I don't really have much brand loyalty, but for a decades I raced Yamaha TZs.... but a smart person doesn't wear a KTM or Husqv t-shirt into Daytona's Boot Hill Saloon

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get outa here, this is KTM land.
My old TZs would get no more than about 20 hours, it was the price of racing.

TZs would explode if you looked at them wrong.
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Just now, markit said:

TZs would explode if you looked at them wrong. emoji12.png

Sadly, very true. Worst was the 1980 TZ250G, last year that they used the ancient R5/RD cases that severely restricted port sizes. They went crazy with piston ports, cut the back of the piston out, etc. you might get 5 hours on a fresh piston and rings. Which means every weekend you replaced them. Next year got new cases and separate cylinders (kinda like two KTM two stroke cylinders side-by-side) and they were much more reliable. Might live 50 hours before blowing up.

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Sadly, very true. Worst was the 1980 TZ250G, last year that they used the ancient R5/RD cases that severely restricted port sizes. They went crazy with piston ports, cut the back of the piston out, etc. you might get 5 hours on a fresh piston and rings. Which means every weekend you replaced them. Next year got new cases and separate cylinders (kinda like two KTM two stroke cylinders side-by-side) and they were much more reliable. Might live 50 hours before blowing up.

I had RDs and raced them for years, decked cut ported chambers the works. I know your grief. lol never had a TZ but always wanted one

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