Posts
2080
Joined
3/12/2012
Location
San Antonio, TX
US
Edited Date/Time
7/15/2019 7:43am
This is going to be a slow build because I'm also saving money for a house, building a car, and a gf that hates that I waste money like it grows on trees lol.
This is where I started with a stock '18 KTM 250sx in October of '17. So far I've rejetted it and worked on getting used to riding again after a 10 year break. I installed the ride engineering CRF steering damper bracket and damper they had and it helped a great deal in turns and dropped one tooth on the rear sprocket.
With this round of changed I installed the Neken air/spring clamps so I had to build a bung and weld it to the steering neck. (I'll get a picture later) for the steering damper. I also swapped in the TLD McQueen kit. I changed some suspension settings and Hopefully tomorrow I'll get to ride it and see how it feels.
Next up on the list is depending on how it handles this weekend. The bike has been handling well, but some pictures the gf took for me confirmed that the rear suspension is packing in braking bumps and the front rides to high in the stroke in turns. If my adjustments help then I'm aiming for exhaust. If it still isn't better then I'll be headed for a revalve front and rear. Still undecided on who to go with though, local race tech guy, FC, MXT, or a different local guy with national proven results.
Currant build:
jetting
MJ 490
PJ 37.5
Needle 42-75
Clip 4th position or 3rd depending on temp.
Needle jet s-4
AS 1.5
U4.4 mixed 60:1 with amsoil donionator
Suspension settings:
Front Rear
rebound 19 rebound 14
compression 23 low speed 8
air pressure 144psi high speed 1.25
sag 110mm
CRF 20mm Showa steering damper
Neken air/spring triple clamps
49t rear sprocket
Power valve turned in 1.75 turns from all the way out. Stock yellow spring.
This is where I started with a stock '18 KTM 250sx in October of '17. So far I've rejetted it and worked on getting used to riding again after a 10 year break. I installed the ride engineering CRF steering damper bracket and damper they had and it helped a great deal in turns and dropped one tooth on the rear sprocket.
With this round of changed I installed the Neken air/spring clamps so I had to build a bung and weld it to the steering neck. (I'll get a picture later) for the steering damper. I also swapped in the TLD McQueen kit. I changed some suspension settings and Hopefully tomorrow I'll get to ride it and see how it feels.
Next up on the list is depending on how it handles this weekend. The bike has been handling well, but some pictures the gf took for me confirmed that the rear suspension is packing in braking bumps and the front rides to high in the stroke in turns. If my adjustments help then I'm aiming for exhaust. If it still isn't better then I'll be headed for a revalve front and rear. Still undecided on who to go with though, local race tech guy, FC, MXT, or a different local guy with national proven results.
Currant build:
jetting
MJ 490
PJ 37.5
Needle 42-75
Clip 4th position or 3rd depending on temp.
Needle jet s-4
AS 1.5
U4.4 mixed 60:1 with amsoil donionator
Suspension settings:
Front Rear
rebound 19 rebound 14
compression 23 low speed 8
air pressure 144psi high speed 1.25
sag 110mm
CRF 20mm Showa steering damper
Neken air/spring triple clamps
49t rear sprocket
Power valve turned in 1.75 turns from all the way out. Stock yellow spring.
Will be following this my friend, have been looking out for a '18 myself but found a '14 with the 300 SXS kit so have bought that for the time being!.
How do you find the vibration?.
Enjoy coming back to mx.
I see youre in Texas, hopefully youre building a turbo car lol
The Shop
Here is a few laps, don't mind the big table, I wimped out after I came up short earlier in the day and tweaked my ankle.
https://youtu.be/yENaNpVDwb4
Awesome footage, tell me more about the Garmin please!.
Anymore time in the seat?.
I compared the Garmin Virb ultra 30 to the GoPro Hero 5 Black as the 6 wasn't out yet. If you're just walking around the GoPro is the way to go. The Garmin is a better choice for moto as it shoots in a higher quality with stabilization than the GoPro does. I shoot 2.7k@30FPS. I need to play with it some more as its not as stable of video as it was with the original settings I had and I always forget to change it before I go out and ride. You're also able to link a ton of data loggers to it. I only use my heart rate strap with it, but it will also link to my Garmin VivoActive HR to turn the camera on/off, take pictures or start video. I has better sound than the GoPro and uses all of the GoPro mounts. The case it comes in is good to 40m water depth.
https://youtu.be/mgZzfxMrA04?start=47
The expansion chamber is much larger on the bike and runs a bit closer to the radiator shroud. Overall it fits pretty nice and I'm looking forward to riding it in a few weeks to see how it does.
Would you mind showing pictures of how you are running the Showa 20mm stabilizer and the neken sfs triple clamps? I am guessing you welded on a bung like I did but would love to see what you did. I am running the 24mm, racetech gold valve and Motovate Racing off road re-valve with the spring/air Neken SFS triple clamps.
I'll have to get pictures of it later when I get home. I used a 3/4" bolt I had laying around and cut it down to 28mm. Checked it up in a brake lathe and ground it down to fit the stabilizer, welded it on, then drilled and tapped a hole. I revalved mine by moving the shim stack around based off a link I found on thumper talk and filled it with 15w fork oil.
Pit Row
MXA Review
"(3) Performance. Every MXA test rider loved the 2017 KTM 250SX powerband; but, if given the opportunity to tune it to our tastes, we would want more top-end power and some added over-rev. The stock pipe delivers incredible midrange but falls off quickly after its peak at 8200 rpm where it was making 47.30 horsepower. With the Pro Circuit Works pipe installed, peak is moved to 49.60 horsepower at 8300 rpm. That is a 2.2-horsepower gain at peak, but most important, the pipe didn’t fall off as quickly after peak as the stocker. The Pro Circuit pipe made the same power as the stock pipe from 5000 rpm all the way to 7200, then the Pro Circuit pipe made 1 horse more at 7500 rpm, 1.6 more at 8000 rpm and 4 horses more at 9000 rpm. Best of all, it kept all the good traits of the KTM 250SX and just added more power after 7200 rpm."
I cannot reiterate how much more noticeable the overrev was
I would not consider myself a very good rider 51-year-old vet but as I said made a noticeable improvement
Also, I remembered to grab a picture of my steering stabilizer that I was asked about.
Hope all is well mate.
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