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If I were choosing between a YZ125 or KTM125, I'd take the KTM without hesitation.
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I think the moral of this thread is that everyone will have a different opinion, all you can do is take this info with a grain of salt and make your own choice. Everyone has a different feel for what they are looking for in a bike.
Just on the headshake thing, I am not going to jump on anyone on this board. Everyone is entitled to their opinion. Everyone has had their own experience. And also, what a bike does with a 115 pound rider on it is going to be different to what it does with a 200lb rider onboard. I will say that I have had my fair share of headshake on the YZ, and once so far on the SX. On the YZ it tends to be on fast straights as I accelerate through 3rd into 4th and the front is very light. On the SX, it was heading into braking bumps, downhill, from a tapped out in 6th gear back straight. So IMHO, the SX was caused by me carrying too much speed into a section that had gotten super chopped out, whereas the YZ was due to accelerating hard and perhaps I was too far back on the seat, but it didn't wheelie, it just bucked. To put it into perspective, though, it's a 125 and I am a grown adult. Headshake on a 125 is almost funny, unlike say a 450, on which it feels positively "deathly".
Another thought on the AER48 forks
I think some of the people that have disliked the AER forks may have had them set up too firm on the air spring - i.e. too much air pressure in the chamber. I made the same mistake my first moto. Then I changed it for the second moto and saw the light. I actually ended up with a setting which would theoretically be one spring rate too soft for me, but I adjusted the clickers slightly (4 clicks firmer) and it was perfect (for that track, on that day). IMHO, these forks are very supple and extremely difficult to bottom. The exact opposite of the 4CS.
Also, thinking further about the KYB SSS - I think these forks are superb on the YZF range (I have owned several YZ450Fs with these), but I cannot brag about these forks on a 125. Yes, they are good. Maybe even almost great. But they are not the quasi-factory-chest-of-gold that people like to make out.
The air forks on the 17 are better but the majority of people are still buying cone forks or doing the spring conversions.
My friend just bought his son a new KTM 125 and sent it to Earl Shuler for valving etc. I'm anxious to see how it works. I know Earl does suspension for a lot of the MXA guys.
Bottom line is if you buy the KTM you need to find a good suspension tuner or choose the YZ and find a good motor builder. At the end of the day both 125s will mod out about the same but the KTM is pushed farther to its potential from the factory. The KTM has a longer but slower revving type of power but it is faster stock. The YZ is a little easier to ride but requires you to shift more often. There were several riders winning area and regional qualifiers on the YZ's and Gavin Leachman set the fastest lap at Mammoth Mountain. Even though it's time for a new YZ the current bike is still competitive.
Maybe you are not fast enough to expose the problems?
But forget about the suspension and let's talk about the other issues. Broke trannys in 125s and 250fs on 16s and 17s. People have and are still waiting for parts! How many trannys broke to still not have parts months later? It's also well known the swingarms have too much play which causes excess vibration. It's so bad on the 85 Nihilo makes a kit. You must shim the right side of the swingarm to take up slack and keep the chain and sprocket parallel. What about the powervalves terrible design? Ours stuck at 8hrs and my buddy's stuck at 10. F1 moto makes a new arm to help with this.
So it's not only the suspension I had issues with.
Pit Row
If I bought a KTM and the tranny goes after 10 hours, while it newer happened with my old clapped yz125 with 200 + hours I would make a flat tyre on Pit Beirers wheel chair. But I almost always use the clutch when I shift, maybe that is the reason why I newer damage a gear box.
Everyone is different but I can say this in regards to all brand new 250s I have bought:
YZ- good suspension stock, didn't need to respring, ended up with Factory Connection revalve to sort it out
2013 250sx- not as good suspension as the yz, had to respring and revalve so it didn't feal like the forks would kill me
2017 250sx- Very good stock suspension, running less air than stock and 1 lighter rear spring, no revalve. First suspension I've had stock that I feel very comfortable on without considering a revalve.
29 of the 40 125's came from Austria in EMX last week, compared to 8 Yamahas
The claim of "most people run Cone Valves" is incredibly over exaggerated. I have seen one maybe two sets on KTM's around here...and they were on Vet riders rides. 6 or 7 of my friends are currently on AER's and love them. I would like a bit better action in the small chop....but they are the best forks I have ever ridden out of the box.
I bet you are one of those people who thinks there isn't an issue when riders say, " I can't thank Blah, Blah, Blah."
Anyway I'm just telling you what I've personally seen with lighter riders on the KTM.
Honestly I probably would have considered keeping the KTM if it wasn't for my friends loosing their trannys and the powervalve issue. I did notice everyone has avoided commenting on those issues???
If we were buying 65s or 85s I would definitely get a KTM. The 125 just didn't work for us.
This is how you slowly marginalize and phase things out. Give it a few more refreshes and it will be off the fork guards also.
The shimming came info came from the factory KTM mechanics you jackass. It's a known problem! I even posted how to fix it on vital.
To the OP. Get the ktm.
My last bike I had was a 250sx with KYB SSS 2013. I replaced it with a 17 with the new AER fork, was skeptical. Its a great fork, shock was great on both years. The new KTM chassis is really better. I couldn't imagine you would regret the purchase of a new KTM vs a 11 year old 125.
Though if money was no object I would buy a few TM 125s. I rode a bone stock one and was really impressed. Though you would 2 or 3 becuase no one is going to have parts locally.
Post a reply to: Going from yz125 to sx125 (2017)?