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247
Joined
1/23/2018
Location
CA
I got my first ktm im running around 37hrs on the stock piston I've heard between 30-40 hrs is safe so i order a vertex piaton kit size b as everyone says over 25hrs take size b. I know vertex is oem I feel safe using there stuff but I've spoke to people at the track and everyone is saying just use oem ktm but vertex is the oem provider so are people just be stupid or is there really a quality difference between vertex kit and the ktm vertex that you buy that has ktm ridden on it .... ???
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The easiest time they have is with a novice rider, riding at 1/4 to 3/4 throttle on the 300cc trails. Those bikes can go 100s of hours on a piston.
On the other end of the spectrum is an MX-guy that knows how to operate a 250cc and won't let it come down.
I'd say I'm more in the second scenario and I ran my 250SX to 100 hours/piston without a problem. I am very careful with jetting and if you are running in the sand and are a bit off/lean, that can takes it's toll.
If it's your first piston, I would definitely break it down at the 40hr or so mark and look carefully at all the parts, take pictures, maybe bring the piston and head to the nearest KTM shop to look at with you. The cost saving between running it 50 or 100 hours is really minimal especially if you are driving a ways to go race rather than just a weekend warrior.
My best point of reference is the guys who I race with on a regular basis that have been running the bike for a few more years than me. Talk to his Dad/mechanic or pro tuners and are careful/fanatical about maintenance and inspecting everything carefully. Ask a couple more questions than "when do you change a piston". Usually by the second or third question, you can tell if they are just following along with someone else's BS rule of thumb or actually looking at the parts carefully and adjusting along the way.
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