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My SFX-250 review

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I rode mine for the first time this weekend. Also have an 05' CRF450. The reviews I've read were almost hard to believe. After a couple of hours on the bike I can confidently say that yes indeed, it is fast. However, it's not ground breaking like the magazines say. On Racer X, 'Bad Billy' said he pulled his buddies even when they were on 450's....I just don't see it. Of course from everything I've read, the bike is suppose to get better and better as it breaks in, and that the engine breaking slowly decreases w/ break in. To me the bike has almost NO low end power. It's a screamer....all RPMS, and it never signs off. One thing that really surprised me was the handling. Very good. Suspension, much better than I would have thought. Soaks up the big stuff w/ no problem, but small chop/ braking bumps...it's gets pretty dang busy, and requires full attention at speed. Brakes are the best in the business!

If anyone has had low-end power issues, let me know. Maybe jetting (I'm @ sea level) or maybe I'm just used to the Big Red 4-5-0!!

The Little pumkin is a BLAST to ride!!

SD

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okay, it has all botoom end power and it revvs fast, but its best too short shift. you dont wanna ride on the rev limiter. not with this bike

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I rode mine for the first time this weekend. Also have an 05' CRF450. The reviews I've read were almost hard to believe. After a couple of hours on the bike I can confidently say that yes indeed, it is fast. However, it's not ground breaking like the magazines say. On Racer X, 'Bad Billy' said he pulled his buddies even when they were on 450's....I just don't see it. Of course from everything I've read, the bike is suppose to get better and better as it breaks in, and that the engine breaking slowly decreases w/ break in. To me the bike has almost NO low end power. It's a screamer....all RPMS, and it never signs off. One thing that really surprised me was the handling. Very good. Suspension, much better than I would have thought. Soaks up the big stuff w/ no problem, but small chop/ braking bumps...it's gets pretty dang busy, and requires full attention at speed. Brakes are the best in the business!

If anyone has had low-end power issues, let me know. Maybe jetting (I'm @ sea level) or maybe I'm just used to the Big Red 4-5-0!!

SD

I am glad to know I am not the only person who felt that way after my first couple of rides. I had my 4'th ride yesterday. And the bike now has about 2-3 solid hours on it. About 5 "testers" rode it yesterday for around 6 or 7 minutes each yesterday. They all got comfortable on it fast. The motor is getting much better in terms of low end (2nd gear seems longer and stronger), as well as less stalls, and starting after hot stalls in corners etc. A couple of of the testers didn't stall it at all. The suspension is also getting much better. Still feels a little busy in the small stuff, but not near as bad as the first ride. And honestly, the engine breaking is a non issue for me...

Did you stall it any? If so what was your re-fire procedure if you stalled when doing pretty hot laps?

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Guys. I have ~6 hours on mine now and I have been through all the issues you describe. Basically the bike takes awhile to break in. The first time I TRIED to start it, I spent 1/2 hour kicking on the thing (hence my login name). I learned that it took a lot of idle screw and basic 4 stroke starting technique to get it to light. Next was the idle jetting. When it was new it needed a richer jet (45) to run at all without stalling (which was a pain because it was so hard to start). Now that it has broken in a bit I am all the way down to a 35 idle jet which really cleans up the bottom end but then the low end had a slight hesitation. I have increased the needle jet one clip and that has made it pull really hard down low. I also read in DR that advancing the accel pump helps which I intend to try on next ride. Oh, seal the header pipe with high temp silicone, it will reduce the popping on decel. Good luck getting the pipe off though. You have to remove the shock! Now the suspension... The forks when I got them had 28 clicks of rebound available on one side and 22 on the other. This really bummed me since I was all the way out at 22. I also didn't like the fact that they were different so I ripped into the forks. I found that the one side with only 22 clicks also had an extra preload spacer installed. I removed that and started to play. I found that if you preadjust the clicker to 28 before you put is back on it would give me the added clicks (don't go too far as the needle inside the cap will screw out past the knob engagement). I lowered the oil level almost 5/8"!! (MX Action suggested this). IT WORKS BIG TIME. The harsh mid stroke is gone and the bike is much more stable at speed (head shake was an issue at first). I swapped the triple clamp to the 18mm offset which helped as well. I have adjusted the shock clickers a bit (reduced comp added reb). The shock responds well to adjustments as you can really feel changes. I was having trouble with a little seat bounce jump as it was right between 2nd and 3rd gear so I added a tooth to the rear (another MX Action suggestion) and Viola the added bark is really impressive. Bottomline this bike needs some time to break in and proper setup. It only gets better with time and you can really fine tune it as changes can be immediately felt. Invest the time and you will be rewarded. I LOVE THIS THING!!!

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Guys. I have ~6 hours on mine now and I have been through all the issues you describe. Basically the bike takes awhile to break in. The first time I TRIED to start it, I spent 1/2 hour kicking on the thing (hence my login name). I learned that it took a lot of idle screw and basic 4 stroke starting technique to get it to light. Next was the idle jetting. When it was new it needed a richer jet (45) to run at all without stalling (which was a pain because it was so hard to start). Now that it has broken in a bit I am all the way down to a 35 idle jet which really cleans up the bottom end but then the low end had a slight hesitation. I have increased the needle jet one clip and that has made it pull really hard down low. I also read in DR that advancing the accel pump helps which I intend to try on next ride. Oh, seal the header pipe with high temp silicone, it will reduce the popping on decel. Good luck getting the pipe off though. You have to remove the shock! Now the suspension... The forks when I got them had 28 clicks of rebound available on one side and 22 on the other. This really bummed me since I was all the way out at 22. I also didn't like the fact that they were different so I ripped into the forks. I found that the one side with only 22 clicks also had an extra preload spacer installed. I removed that and started to play. I found that if you preadjust the clicker to 28 before you put is back on it would give me the added clicks (don't go too far as the needle inside the cap will screw out past the knob engagement). I lowered the oil level almost 5/8"!! (MX Action suggested this). IT WORKS BIG TIME. The harsh mid stroke is gone and the bike is much more stable at speed (head shake was an issue at first). I swapped the triple clamp to the 18mm offset which helped as well. I have adjusted the shock clickers a bit (reduced comp added reb). The shock responds well to adjustments as you can really feel changes. I was having trouble with a little seat bounce jump as it was right between 2nd and 3rd gear so I added a tooth to the rear (another MX Action suggestion) and Viola the added bark is really impressive. Bottomline this bike needs some time to break in and proper setup. It only gets better with time and you can really fine tune it as changes can be immediately felt. Invest the time and you will be rewarded. I LOVE THIS THING!!!

How much do you weight? what type and level rider are you... what were you ridding prior to this?

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165 lbs. MX mostly, some trails. I am slow. Been riding 30+ years, don't race just get in peoples way ;->, proud to be a "poser". Been riding my 520SX (converted to 6 speed) at different tracks and the mountains of Oregon (when the tracks are flooded) for the last 5 years. Been on KTMs since '82.

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I added an SLP power pack to mine(part # 14-268 $39.00) and it helped the bottom end out a bunch. I did have to re-tune the bpilot and AC, but it was worth it. Added one tooth to the rear as well. Added to clicks rebound to the rear. That is as far as I have made it. Will keep playingwith it, but over all I love this bike. KTM relay thought this thing through.

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Does anyone know if a Q2 fmf silencer from a 400/450 will fit the sxf?? THANKS.

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Does anyone know if a Q2 fmf silencer from a 400/450 will fit the sxf?? THANKS.
no it wont they are different because my brother has a 525 and it wont fit the 250 sxf

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Gonridin, What did you end up with on your idle jet? Did you advance or retard your AC? Did you do anything with your needle? Does the power packs go in both sides like the Power Nows or is it just the cylinder side? It looks like they have 3 stages (2 dividers) instead of the 2 stages with the Power Now. Is that true? The Power Now made a nice difference on my 520SX but they are pricey. The SLP looks simple and is a bargain at $40.00.

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35 pilot

2 turns on air screw

Stock needle

Advanced the AC so it barely misses the slide. (still playing with this)

My squirt time is almost 4 seconds. Way to long. I will try a longer rivet on the pump diaphragm as soon as they get here and shorten the squirt down to 2 secands and try that.. .If that doesn't get me where I want to be, I will modify the carb with the BK mod to have total controll over the squirt length. I hate to do to much until the motor has completed the break in, as I could just be chasing my tail.

The power pack is installed on the Motor side of the carb, and yeah, it is a way better value than the power now. I dint like to run them on both sides as it can hurt the top end air flow if you put to much junk in the air intake track. I like dealing with SLP as they are just flat out straight up honest. They tell it how it is, with out the B.S. They make Killer snowmobile parts, which I have used for years. I trust them. :eek: Oh yeah.....it is two plates which will create 3 stages. I hope this helps. My bike is not perfect.......Yet, but I think I can get it relay dang close. It is almost their as it is. I think sometimes I enjoy the tuning as much as the riding :applause:

P.S. I am at 4800ft elevation.

Power-Pack-motorcycle1.gif

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4800 FEET!! No wonder you went down on your pilot. The strange thing is I am at ~1500' and I am using a 35 as well. It has been really hot here lately though. I am running 3 turns on the fuel screw but a 38 is still a little blubbery. I'm going to try to find something in between. What is the BK mod? It isn't the Boyesen is it? I have to confess I am a tinkering junky as well. After 30 years riding my technique isn't getting any better (probably the opposite) so I have to get any added performance from my bike not my bod. This bike responds so well to changes it is incredible. Let me know where you end up on your jetting.

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Kick-Til-Mad, where in Oregon are you? Just got my 250SXF, zero hours on it as I am of to Unadilla with my son Rory Sullivan

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Really, I was going to that race until my business trip back east fell through :-<. I live in Grants Pass. I ride at RVMX almost every week. I also travel up to Portland ~ twice a month. If you are near by, maybe we should get together.

Ted

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Well, I would read the following:

https://thumpertalk.com/forum/showthread.php?p=137721#post137721

this one talks about Yamaha's FCR carb, but the idea is the same on all modern 4-strokes that use a FCR pumper carb.

http://www.thumperfaq.com/jetting.htm#PJ

https://thumpertalk.com/forum/showthread.php?t=239791

the following describes the BK mod

http://www.thumperfaq.com/ap_mods.htm

I would also save this site in your favorites as it has some great info, even though we ride KTM's. I suspect you will be reading for a while. Trust me, it's Worth it.

http://www.thumperfaq.com/sitemap.htm

Good luck.

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Really, I was going to that race until my business trip back east fell through :-<. I live in Grants Pass. I ride at RVMX almost every week. I also travel up to Portland ~ twice a month. If you are near by, maybe we should get together.

Ted

Kick- when you siliconed up the header- was this at the head or at the can or both?

I running at sealevel to 2000ft... went for another ride today(which should have finished break in)- I changed the main to 170 and installed a PowerShot- ran great for half the ride- started awesome, but then it started to act really lean lots of popping at decel and would also not want to run well at idle(not all the time, something it would idle just fine and then be cloudy off idle) and just above.. I went richer on the screw-- that made it worse, so I went leaner on the screw and that made it worse... so I thinking an air leak is the culprit..... I don't know.. has me scratching my head...

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Air leaks are so intemittent it is really hard to say sometimes. I sealed my pipe only at the head but the silencer could probably use it as well. Why did you go up on the main? The top end on mine has always been awesome just down low it has had some issues. The change when it gets hot (plus the easy starting when cold) says you are too rich down low. The first effect of an idle jet that is too rich is that the fuel screw has little if any effect. I would suggest that you put a smaller idle jet in. What is a "Powershot" are you talking about the "Quickshot" AC cover from Boyesen? I am not sure but I think those need slightly leaner jetting as well. How much time do you have on the engine? These things take awhile to break in. Mine has 6 hours on it and it is just now starting to settle down. Oh one misconception... rich will also cause popping on decel if the bike is really hot.

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Gonridin, Looks like I got some reading to do. Thanks alot information is power and like most of us I am ALWAYS looking for more of that. (and to think I just got off a 520, go figure)

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