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SXF 250 Hydraulic Timing Chain Tensioner

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So I've been working through some issues with my recently purchased 2014 sxf 250 ( can see my active posts for past issues but will give a quick overview).....

The bike had a new top end with maybe 30 minutes on it when I purchased. After I originally purchased the bike,  I only got about 30-40 minutes of ride time before the timing chain tensioner collapsed on me. The timing jumped a tooth and wouldn't start. 

I purchased a factory replacement and installed, reset timing and all was good (next I ran into a fuel pressure regulator issue where the regulator diaphragm deteriorated....& have now fixed that issue). Replaced the entire fuel system along with new regulator.

Rode bike around easy for 15 minutes or so and no problems....was excited I finally got her figured out!...but then...geeezzzz

Now to my next problem and a revisit to my first problem. Took bike out today after its been torn apart for the last month dealing with & diagnosing the issues. Made it about 10 minutes down the trail, approached a very sandy berm, going to hot, I blew out the berm and laid bike over on its left side ( nothing bad at all, just laid down). Bike was still running...I hit the kill switch and lifted the bike up. It was maybe running on its side for 5 seconds or so before I lifted it up. I went to start it again (electric start) and just a click...every time I tried to start, just a click. Bike wouldn't roll forward or reverse unless clutch was engaged. Buddy towed me back to my truck. Same symptoms as the original collapsed timing chain tensioner, only difference was that this time I laid bike over.

Get home, pulled the valve cover to see the cams, pulled the case plug and turn motor over manually. Could see the timing chain look like it was about to jump & then "CLICK " !!!! The hydraulic timing chain tensioner was evidently collapsed & popped back open!

This is a brand new factory tensioner with maybe 15 minutes time on it. I know the factory ones are an issue but a brand new one shouldn't have issues after 10-15 minutes run time.

Do you guys think I'm having a oil pressure issue? There was oil on the upper valvetrain & under valve cover when I removed it for inspection & never heard any odd sounds coming from motor, never lost power.

Should I install a new oil pump assembly? along with a MANUAL adjustment tensioner to get away from the hydraulic style? Are there any known  issues with the factory oil pumps? I know they have had issues with the factory tensioner.

Thanks for any and all suggestions guys!

 

 

Edited by KTM73
Misspell

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I was looking at those KathleanTribeMotocross....

Just wondering if I'm having a oil pressure issue with motor? Not sure how to figure that out and don't know if the pumps ever go out or wear out.

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i wright it many time before . we do not even start a new bike with the oem tensioner , first thing we do is remove it and puth a manual one in . the only down site of a manual one is you have to check the tension freqently , this is the only downsite . ride safe ,go manual. 

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Why do you think that a brand new one would collapse so quickly.....after 15 minutes of riding? I understand theach design is not great.

Anyone think there's ano oil pressure issue and that's why it's collapsing? Any way to figure out if there's an issue with the oil pump?

I will definitely go with a manual tensioner.

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if the oil pressure is to low ,the first thing thats go wrong is ,the cams wil seize in the head , even if you forget the 0 ring on the oem tensioner (i do not think you did) the los of oil pressure is at the hole system ,and cams will seize . the problem with the oem tensioner is ,it is not relaeble , it can work for years and it can work for 15 min. so for this reasen i remove them as first . 

 

Edited by speedboot
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Ok then I will order a manual tensioner with the oil plug to force more oil to the top of the motor like the nihilo tensioner design.

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Ok then I will order a manual tensioner with the oil plug to force more oil to the top of the motor like the nihilo tensioner design.

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My new manual timing chain tensioner will be in tomorrow I hope. I went with the nihilo concepts with the oil plug.

 http://www.nihiloconcepts.com/mobile/Product.aspx?ProductCode=NMCT-BLK

Thanks for the suggested part KathleanTribeMotocross.

Anyone know if theres a way to check oil pressure in the motor? And if so, what's the pressure supposed to be?

My understanding that if I didn't have decent oil pressure then the cams would have seized up....

It's just hard to think that after the original tensioner collapsed, and then replacing it with a brand new one, it would do the same thing within 10 minutes of ride time. Now, the motor did run on its side for a few seconds after laying it over. Think that's why it might have collapsed?

Just think how many times guys fall off these ktms and their still running. I'm just confused on how this is happening... Hope the new manual tensioner fixes my issues. 

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Ok new tensioner installed, timing set....drum roll please ....ignition  & BRAAAAP!

Back in business! 

Still has me puzzled on why a brand new factory one would have only given me 10 minutes ride time before it bled down but... Timing chain tensioner issues should be a thing of the past as long as I keep up on the adjustment of the new manual one ?

Like a lot have said, ditch the hydraulic style for a manual....I wasted time and money with a factory replacement. To think that I had two factory ones fail me and no marriage of internal parts becoming one together aka piston & valves; a Blessed guy right here!

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