2019 KTM 150sx Lower Rod Bearing Failure

tsmitty2661
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tsmitty2661
Hey Guys. Had my lower rod bearing go on my this weekend. Unfortunately it was on lap 3 of the day, but fortunately it didn't go on the face of a jump. Bottom end has about 130ish hours on it, is this a typical duration out of a crank? It did fail going up a fresh prepped hill where i know i was probably topped out too long. Running 40:1 with super M and vp110, worth going down to 32:1? I am running AJ's jetting specs, only difference is i had to go down to a 17.5 pilot jet
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walent215
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walent215 7/5/2022 5:04am
7/5/2022 5:04am
130 hours would be long past service interval for a high rev 2t
Ratio sounds fine as long as your jetted properly
I’d cut your hour threshold in half if it were my bike
60-80 hours
IMO
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FGR01
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FGR01 7/5/2022 6:58am
7/5/2022 6:58am
Yeah, you gambled too long.

I'm curious about this 17.5 pilot ??? Do you mean 27.5 ?
tsmitty2661
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tsmitty2661 7/5/2022 9:00am
7/5/2022 9:00am
FGR01 wrote:
Yeah, you gambled too long.

I'm curious about this 17.5 pilot ??? Do you mean 27.5 ?
Lol no it is a 17.5. I have no clue why i needed to go that low, i actually posted the question in the jetting forum and dont think i got a response. I have the exact setup per the jetting thread, float is dead nuts on, jet block gasket replaced, even needle valve and oring replaced but i was fouling plugs till i dropped down to a 20, then with the 20 i was 3+ turns out, so dropped it to the 17.5. It would run fine on the track since i wasnt lugging the bike but then when i would lug back to truck it wouldnt start over for next moto. I would pull the plug and it would be wet fouled. Beats me but now it runs fantastic
miketherider 7/15/2022 6:57am
7/15/2022 6:57am
130 hours is a lot on those bottom ends, usually you have to check around 50.

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CarlinoJoeVideo
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CarlinoJoeVideo 7/15/2022 9:20am
7/15/2022 9:20am
On my 125 I always did pistons at 25 and bottom end at 100 if your jetting is correct.

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