I recently just purchased my first 2 stroke which is a new to me 2020 KTM 250xc Tpi. Been riding 4 stroke previously. Anyways, when starting the bike before a ride I’ll hold the starter for a couple seconds until it starts to run but the bike kind of sputters then dies after a couple seconds. The bike will do this a few times before it finally seems to catch and starts to idle just fine. The bike runs amazing as well and has no issues starting after it’s been warmed up. So my question is, is there something going on or is this just a quirk of the tpi system on these bikes? Riding 4 strokes for the past couple years I’m used to those things just ramping right up after starting so this is a new experience for me. Only reason im worried is I’ve heard a sign of a top end being ready for replacement is hard starting but this bike only has 70 hours on it. So it shouldn’t be too bad right?
Edit: Forgot to mention I’m not touching the throttle when starting per what I’ve read about these tpis. This issue still persists.
Prob time for top end depending on how it was ridden 70hrs is ready
New plug and after cylinder is warm, hold it wide open & clean it out….
What's the ambient air temp?
Are you using the cold start knob on the side of the throttle body?
Ambient temp was around 60f. Still happens with the cold start pulled as well.
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I guess the is brings up the question of how trustworthy is the hour meter. The 250xc tpi comes with the small oem ktm hour meter right below the bars. There has been 2 previous owners before me. Is it easy to tamper with this to make the bike look like it has less hours than it does? I’ve heard you can take them into a dealer and when they update the ecu it shows the actual hours. I’m not sure if that’s actually a thing or just some bullshit I read on Reddit though lol.
My 2020 300 started to do this when the plastic filter in the tank went bad. They crack where the two pieces are bonded together. The symptoms slowly got worse. It’s a good idea to replace it with a metal one regardless. Napa 3095 is the correct one. As far as hours go , if you don’t have the magnet in the brake disc , it won’t record hours on the meter.
Dealer tool will show true hrs
It's easy to tamper with or replace the rider-facing hour meter. The ECU can also be replaced to restart at zero hours, but it's a lot more than a $30 hr meter.
It's also standard advice to do an engine service/inspection whenever you buy a used bike.
A lot of true low-hour TPI have worn cylinders and rings due to incorrect starting procedure and interruption in oil pumping.
If they're ridden hard, they detonate and eroding piston/plug can cause a quick drop in compression, so there are a lot of variables.
You could inspect through the plug hole (micro camera), through the exhaust port, or run a compression test or just lift the head and take a peak.
Could also be that fuel filter issue (above), dirty sensor or sensor tube.
My TPI blows a lot of crud out of the crankcase vent and that stuff dribbles down inside the intake. That can make it hard to start too.
This is super helpful I appreciate it. Definitely gonna bring it into my local dealer to have them update the ecu to the most recent map but also so I can see if the hour meter is accurate. I got to service the forks this next weekend anyways so I’m gonna pull off the tank and take a peek at the piston and cylinder. If it wasn’t a tpi I’d just assume the idle was too low and that’s why it sputters out at first. I’ve heard of an idle screw mod that I might consider if it seems like the cylinder and piston are fine.
I created a Reddit post with a video of the issue so it’s a little easier to see what I’m talking about.
https://www.reddit.com/r/Dirtbikes/s/lcMhvK2Xpq
That’s what mine did , then once it started to idle good it would bog out on the initial ride from the truck for a minute or so. Sort of how a carbed bike does when they are cold. It progressively got worse. Even started to get that pipe bang sound. A clanking type sound. The new filter made it run like new again. I switched to standard hose clamps and just reused the O ring on the faceplate. I’ve had friends that when theirs cracked it only affected the higher revs. Mine was more like yours. I replaced the crankcase sensor and it didn’t help. Any auto parts store will have that equivalent filter. Good luck.
Yeah it will bog and completely cut out when first running. Figured it was tpi thing lmao. Sounds like a have a filter to replace haha.
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