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11/30/2016
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Hixson, TN
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Picking up a 2022 250sx. Looking to do a modest build for moto with some external bolt on parts. Looking for advice from those with experience…..what’s the list of parts that make a difference? I see the jetting thread. Bike will come with mikuni and Lectron and Fmf powercore 2.1.
from what I’ve seen online….
-PC works pipe and 304 silencer. Any difference between powercore and 304?
- Vforce 4 necessary?
-plan to move my suspension, pegs, levers over from current 250sxf
-gearing?
running K2 at 50:1 in my sons 50sx so hoping to mix the same for 250
Most won’t admit it, their egos stay in the way, but an xc lower compression head will most likely lower your lap times and improve the bike.
These bikes don’t need much, I had an 18 that was a great bike. if using the Mikuni, do the jetting stated in the thread and then fine tune for your ability & location. I liked to use 50/50 C12 & pump fuel. A shorty silencer will mute top end over rev. I ran my stock reeds for 100+ hrs. Test different gearing. I always wanted to send out my head to have the squish corrected as they come very conservative but the bike ran so good I never bothered. Great do it all bikes, I did nothing more than XC gas tank & bark busters & raced a few a GNCC”s, where the bike felt great.
They’re solid bikes stock, lack over-rev but no bolt on parts will solve that.
Check reeds soon as you get the bike as OEM KTM reeds aren’t the best.
If you decide to go for a Keihin PWK, I have a really good setting from a member on here.
This is one I built few years back:
Love to know the keihin settings
i have a 21 w keihin
40 pilot
necj 3rd clip
172main
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That’s not far the spec’s I have. The needle is the main part!
42 pilot and a bigger main is the only difference to me, but that could be due to lower temperature and elevation.
Facts, mellowing out that initial hit makes the bike easier to ride.
Any in put on the DEP system on those bikes please?
And how about the DEP systems on the newers 23 + KTM's 2 strokes ???
Can't find any information.
Thanks in advance
Great bikes, I have a 21' and can't recommend a spring conversion enough and get rid of the air forks, in my opinion its the best mod you can make. Also I went with the Kehin carb, pro circuit 304 (long) silencer, added a tooth to a Renthal chain and sprocket and Renthal bars. Bike runs awesome, I do play with the exhaust valve to tune for conditions. I also ordered a Gutz complete seat (softer foam).
300 kit if you can swing it. Really broadens the power and makes it super easy to ride.
I did both a PWK and the Mikuni with the AJ jetting from the tech section. Mikuni is better (with that jetting). Totally transforms the bike. Adds the overrev that it needs and is just smooth and strong bottom to top, as either a 250 or 300. With the 300 kit and that jetting can almost ride the bike in 3rd gear everywhere on most tracks. It's not brutal, hard hitting, or tiresome at all. Make sure you adjust the PV also.
Vforce 4R looks identical to stock reeds and there is no noticeable performance difference. Have not tried the new X version yet.
On the 300 kit is there a different kit for the offroad 300 and sx 300 kit or are the only 1 kit. I mean is it possible to put a 2017 exc300 cylinder on it ?
I am not 100% sure. I think maybe the XC300 cylinder is the same but the EXC may be a milder tune? Or maybe all the difference was just in the head.
Only one "300 kit". Cylinders are the same between all three models. 2017 was the last year of each model having it's own compression ratio(head) and own cdi(timing curve), can mix and match to your liking. I ran both XC and XCW heads on my 2017-2022 250SX's. FWIW the 2019-2022 250SX might be the best bike KTM ever made, and right there will the all time mx bikes IMO
I appreciate this because I have a 21 250 SX and was really thinking about punting it and getting the new fuel injected bike… Strictly out of boredom
my main issue just not as crisp on the bottom end as I would like, but after reading this, I am definitely keeping the bike
I consistently see low hr 23-24 300sx bikes on marketplace for good prices… with an ECU tune these bikes are epic…IMO….
Man, if you get the jetting from the thread right on the Mikuni, lack of crispness will not be an issue...🤩
Mods I've done to my 21 250sx which isn't a lot.
Keihin pwk I like the better snap way it runs with it. Was the first mod I did.
Swapped the throttle tube n housing with the 2016 domino setup. The oem setup from 17- 22 has too much drag. Was giving me arm pump. It wasn't just slightly better it was drastically better. Much much lighter of a pull with the domino setup. Get the 16 throttle cable as well. I did this also in my 21 150sx. Absolutely never going back to the stock setup.
Pro circuit pipe with the long silencer
Suspension I'm now on kyb spring inserts in the forks. Rep full linkage and a kyb A kit shock. I love ridding it especially now.
I found even with just the stock rear shock and linkage setup. The stock spring was too light of a rate. Im 185 190 with gear on. I could bottom out the stock setup. The stock 4.2 wasn't working. I put a race tech 5.0 spring on it. Stopped the bottoming out and kept the rear from squatting too much.
On the kyb a kit shock im running a 5.1 rear spring.
Im new to a 22 150sx and am getting throttle side arm pump only. Pretty bad, too. Experimented with different grips today. Made some progress, then read your domino throttle comments tonight. I wouldn't say my throttle is stiff, is there a big enough difference you say?
I was like you it's not that bad maybe it's the thicker odi lock on grips. Went to my usual renthal full diamond grips. That helped a little bit.
It wasn't until my friend in the pit one day pointed it out. It became obvious it was a bit stiffer harder of a pull. Vs the domino setup on his beta's.
So I swapped it out on my bikes for the 2016 ktm setup. Much lighter pull and when I took the stock 21 housing apart. You could see where it was rubbing against the throttle tube on the inside.
Pit Row
Must haves: Jet the mikuni using AJs thread as a starting point. Best bang for your buck at less than $100. Suspension set up for you - bolt ons dont make you more confident riding.
Nice to haves: I tried living with the ktm throttle body (i have 2019, not sure if yours went to roller design) but i swapped mine to a CR body and cable - night and day better. I had Tom Morgan work my top end, fantastic. Stupid crisp and got some over rev out of the bike. I run a works PC pipe with 304 silencer (long). Play with gearing and power valve based on your style. As others said, these bikes rip once you get the jetting figured out
I will verify SmokinJoes's claim 100% on the 2017+ throttles. My '18 150sx stock cable has a plastic elbow, nearly 90°. I never realized how much drag it had until we bought my son a 85sx, which runs a small pivot wheel similar to the Domino (the 85's wheel is actually part of the cable assembly, but concept it the same).
I ended up with the G2 setup, in which the throttle housing is just a rebranded Domino. Either way I consider this upgrade a "must have".
Good luck with the build. These last couple of carbed generation KTM's are some of the best smokers ever. Enjoy!
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