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You're right, and EFI "should not" ever foul a plug. That's the whole point of EFI, right? Perfect fueling under all conditions at all times. Or so we hoped.
One more thing, on the off road versions of the TBI bikes, due to the larger tank I believe it's very difficult if not impossible to swap the plug without removing the tank. So fouled plugs can be a real headache.
Goof friend had his remaped - it has 20hrs. Just busted the piston. Wrecked cylinder. It's hard to tell what caused it. Bike seemed to run better 100% after remap. ???
Knock on wood, but have had great luck with ours. I bought ours in October of 22, we only have 35 hours or so. From the factory it was kinda slow, but I didn’t have any “issues”. Just recently got a reflash, with a PC exhaust, along with a few other things. It took a while to get it figured out, but now the bike is absolutely pulling. My son is a middle pack B rider and seems to be super happy with it now.
Nah wait for next year or the year after..
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Mine’s definitely rich. I have sponge coming out of the exhaust which I shouldn’t have with a well jetted bike. It’s also slightly blubbering in the middle. It’s not awful, but It’s not crispy at all.
As someone stated above, the KTM engineers were probably scared about blowing top ends and programmed them on the rich side.
What’s really funny is this is the only KTM that I’ve ever owned with the exception of the first year 250F back in the day. For those of you who remember, that bike had all kinds of issues. The main being that once it got hot, it would stall and not restart until it cooled completely down. I lost track of how many times I pushed it off the track.
Nope jetting was spot on.
The spot was about 30-45 seconds after heading in the woods from my back yard. More like it had not completely warmed up yet.
If I can go my whole life without fouling a plug on any bike (from 80s to 500s) I'm sure you can figure it out.
I think I went over 3 years on the plug in my last YZ. I just change them "after awhile".
A properly jetted 2 stroke will not foul a plug.
Update on the kid's 2023 250SX, dealer has had for a couple weeks can't figure out why it wont start. Now they are talking with KTM Austria trying to figure it out. Said it is something with the ECU and the injectors not syncing. I miss the old carb days.
There is no logical reason a dealership should have a two-stroke for 2 weeks and can't figure out how to start it! So happy I didn't listen to my dealership when they try to talk me into the 23 Two Strokes need to be simple kick start and a carb!
I’m a new owner of a 125 XC. I’ve fowled one plug so far. It was my first fowled plug in my 43 years of riding.
I’ve been on a mission since to learn as much as I can about these new beasts. From what I have gathered so far is that there is a period of time after starting the bike where you should not be giving it any gas as the sensors attempt to calculate the EFI settings. Then after the period, most says it’s about 1 minute, you should only give it very little throttle as you ride around and let the engine warm up to operating temperature. Then at that point you are good to go. Many people swear by this method and say the bike has been wonderful since they started this routine.
When I fowled my plug, I did none of these steps, I had already ridden a few warm up laps so I assumed the bike was ready to go. After waiting around 20 mins or so, I started it and just headed straight to the track. My first jump I came to, I was heavy on the throttle going up the face. Once I landed, the bike went bonkers. It was cutting out and bogging badly. I didn’t know it at the time but I fowled the plug. The bike would still run somewhat, but I was able to get back to the pits.
With all of this said, I still haven’t figured out how I’m supposed to do a dead engine start for my scrambles come up.
My dealer told me to stay with my 20 and 22. So happy I did.
Did you have the squish fixed on the KX? Every one of them I owned ('89 and later) was impossible to jet cleanly off the bottom until I had the head modded. After that, no more problems and no fouling (and they were used for woods riding in the SE US, not Baja, desert, etc., so they weren't being revved).
Yeah this was before the 23 hit the showroom floor and they knew anything really about them. I was debating on the 22 because of the crank issues just went with the 22 150sx and replaced the crank! Awesome bike don't think I'll ever get rid of it!
I do think that, eventually, KTM will get the FI systems dialed. I just don't want to be a guinea pig for them.
Even if they do which I have my doubts there's still no tunability which you need on a 2-stroke just by changing the pipe reads head compression you need to be able to tune it!
TSP has a tuner out to cover that. You can even fine tune the power valve setting which is impossible on other bikes.
That's a real conundrum. I don't think there's a solution.
Dick move by Fritz for not keeping the Gasgas bikes carb'd.
They had a chance to make the Gasgas genuinely different from KTM/Husky... more true to what a lot of two stroke guys want (light, simple, badass) and keeping the price even lower, and they literally chose not to.
I'm probably missing the point, but it baffles me.
Pit Row
I can see both sides. First you have an easy to work on and reliable platform (YZ). Most people like/love them. They will go down in history as being one of the best 2-strokes of all time. The absolute pinnacle of 2-stroke design and functionality so much so that given the right rider and track, they can give up twice the cubic centimeters to four strokes and still be competitive in most every class. Once you reach the upper echelons of the sport, it’s hard to compete against the 4 bangers.
Then you have the people that were not happy that 2-stroke development stopped once many of the companies dropped out of the business. A lot of these people are just as loyal to the 2-stroke cause as the traditionalist, but they want even more performance. I know most everyone here remembers the days when every year, the 2-stroke bikes had significant changes. The technology was growing by leaps and bounds during those times. We now live in a time when we only see significant changes every four years or so on the 4 bangers. Forget about seeing 2-stroke improvements, but here you have a company that is starting to invest major capital into 2-strokes again. How could that be a bad thing?
I know this first year or so with the EFI has been questionable as far as reliability goes. The vast majority of these problems are related to one small piece to the equation.
Over the last year and a half, the ECU has been a downer. KTM rushed it and made a mistake in locking down the ECU. I understand why KTM locked it down. They didn’t want little Johnny playing with the ECU settings in his phone app. When you give the ability to riders to control the oil flow down the cylinder, that a bad look for the company when we start seeing blown up engines by the masses.
Now that many of the guys that do this stuff for a living have cracked the code to the ECU, there are some pretty impressive 23/24 KTM dynos being released. I saw one video where a completely stock KTM 125 with a flashed ECU, made more horsepower through a broader range than heavily modded elite level 125. The tuner would not reveal the modified bike builder, but he did mention that it was one of the best dynos that he had ever seen with a 125.
This was a completely stock KTM 125 that bettered it. I know the guy was selling his tune, but I did believe him. Why is it crazy to think that after all these years that a good tuner couldn’t make one of the most technologically advanced two strokes run better than a modded carbed bike using tech from around the turn of the century?
I think things are looking up.
So, in order to get a TBI bike that has the same power as a 2006 YZ125 all I have to do is spend $10K, then another $1K for a GET ECU, then another $400 for a tune? And it will only be 10 pounds heavier than the old carb bike? Solid deal. Yeah being a little facetious, I know. A little.
I’ve seen ECU replacements from the $200 to $250 range. The instance I mentioned above in comparison with the modded 125 was a $250 ECU flash. I watched a video of the bike on the track. It sounds really good.
I understand what you’re saying though. This sport has lost its availability of everyday people that would like to compete seriously. That’s a different topic that I feel strongly about. I do not like the way it’s headed, but I think it’s already too late to do anything about it.
I know of two elite level riders (Matt Burkeen and Jeff Walker) who are bikeless right now. It’s a damn shame when you think about it. I would say that these two guys would rank within the top 50 of riders currently competing in the US. If these two guys were the top 50 in any other sport, they could have their assistant call Yamaha/KTM to have a bike flown in over night while relaxing in their endless pool overlooking prime ocean front property. It’s sad.
I’ll be on the market soon for a new bike. Though I can’t speak for everyone and, only myself, I’m a two stroke loyalist. My issue is with companies throwing bikes out that have constant known issues.
A person should be able to go to their dealership and, purchase a new bike without having to worry about breaking piston skirts. Electrical problems that even the dealerships can’t figure out. I’ve been reading and, trying to make an educated decision on my next purchase for nearly four months. Buying old Honda two strokes, though fun aren’t ideal with lack of parts availability. It says a lot when the only realistic two stroke is a YZ that hasn’t changed much in 18 years. Once again, only my opinion.
I don’t want a four stroke riding PNW single track.
But, I’ll be damned if I buy a new bike that may require another trip to the bank just to ride it after dropping 8K+ on it. I’m venting a bit. It’s just very frustrating searching for something that shouldn’t be so hard to find in a modern 2 stroke.
Simplicity and, reliability.
This... all of this line of thinking... is what used to drive design philosophy in MX/offroad bikes. The K.I.S.S approach. Not that there were never advancements/changes, but they were weighed with that principle in mind. Is the tradeoff worth the added cost/complexity/weight/reliability penalty compared to what it replaces? So much of what Chance (and others) say echoes my thoughts.
Nowadays, it seems like the design intent is finding a way to keep the customer dipping into his (limited) resources to make the bike what he wants - expensive "mods" that aren't DIY ($200-$250 every time you want to "tune" it), recurring subscription costs to access the OE tuning system that eventually aren't supported by the OE... which is planned obsolescence so they can get that wallet opened again.
I know this isn't a popular line of thinking nowadays, but since most of my riding these days is done in the woods, my ideal bike would look similar to the air-cooled IT's or KDX's from the '80's; no radiators or cooling system to fail when far from the truck; RSU forks (open-chamber?) because they give a more comfortable ride versus USD on trail trash; disc brakes are good; linkage/linkless is debatable but linkless would obviously be lighter; carbureted; kickstarter (good luck finding that bike at any dealer).
Result? Lighter, simpler, more reliable, cheaper. All the things I'm looking for in an offroad bike - I'm not looking to line up in Birmingham this weekend, so I don't need a Factory Replica and the cost that comes with it (initial and continuing).
But that's not where things are headed and since I don't want a poorly made, 300 lb foo-foo bike or to drop $15k-$20k to finally get a "real" dirt bike set up how I want it (but still with a lot of things I don't want), I'll stick with what I've got and/or buy whatever is closest to what I want and that I consider to be reasonable in cost.
Good stuff guys, thanks for the dialogue.
I agree with you 100%. I traded my 23 KX250 for the KTM 125. If I had the choice between the KTM or the YZ, I would have picked the YZ without a second thought. The reason for that are the things you laid out in your post, but I’m trying to make the best of it.
If the KTM disappoints me, I will sell it and buy a YZ 125.
I was unlucky enough to own the first year of the KTM 250 SXF. That bike had more problems than my 125 so far. I felt taken advantage of by KTM on that deal. That bike was a dog. It would die once the engine reached a certain temperature and would not crank. It would only restart after it completely cooled down.
If my current KTM doesn’t turn out well, I will never own one again.
Are y’all typing all that just on your phone?
In 23’ they specifically had it in the manual to not warm it up by idling it. The start up routine you’re describing is for the obsolete TPI. Warm your bike up on the stand as you would with a carb two stroke. Once warm shut it off. Go ride it.
You can reduce your tps value to lean it out, make small changes. Get a tps tool if you don’t already have one.
I haven’t fouled a plug in my carb 250s or 125s in the last 20 years, but between my efi sleds(tbi also) and TBI Ktm I’ve fouled probably 50 since 2015.
Good grief, no. I try to use my phone primarily for something unusual - talking to people.
I can't stand trying to use it for almost anything online, much less trying to post on a forum. Between the small screen and the goofy mobile display/interface on most sites compared to a PC, it's aggravating at best (for me).
That’s my fear. I’ve always gotten pleasure out of rebuilding Honda two strokes. With parts availability becoming an issue, it’s time to move on to something more modern.
I’ll be the first to admit, I don’t know sh** about the newer bikes. Hence, my constant reading about them. All I see are, broken pistons, electrical issues, mapping problems, injector problems. The list goes on.
The KTM 300 XC was of interest but, that got crossed off the list. Beta 300 RX is iffy knowing several people having electrical problems. Husky 300 TX falls uncles the KTM umbrella.
I don’t want a heavy, choked out CRF450X.
Not interested in a CRF450WE for single track.
Maybe I’m just stuck in my head going over everything but, I think getting what we pay for isn’t too much to ask of the manufacturers.
Hopefully, things work out for you with the 125.
I've got a '17 300XC. I've called it a modern KDX more than once. Great bike... but it's carbureted and still resembles my other 2-strokes from the last 40 years. Not my dream bike but I really enjoy it, no complaints and I haven't had the headaches described on the new NASA -approved models they've been releasing after '19'
Buying used is always risky, but maybe a you could find a primo '19 or earlier 300XC or TX300.
Also have '06 YZ and CR125s. Parts are no issue for the YZ but for the CR (and my '03 CR250) it's absolutely a reality. That CR125 is a blast to ride, but riding it is like having a box of devine chocolate that you can't buy anymore - enjoy every bite because you know that when it's gone, it's gone!
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