250SX VS 250SXF my experience

Mikey150
Posts
23
Joined
1/29/2021
Location
Sydney, AU
Edited Date/Time 2/1/2021 2:20pm
Hey all.

First time poster here, i thought i would share my experience & opinion of my last two bikes as i'm probably one of a handful who have had both and i wouldn't be surprised if my opinion is a little different to most. I'll try and keep it semi short. I've spent the last 17 years riding mx and have spent most of my life on two strokes.

In the last 6 years i've owned quite a few bikes, i generally own two at a time.
Starting with 14 YZ250F, 06 125SX, 08,YZ250, 17 250SX, 18 RMZ450, 19 250SXF (current bike).

I thought i would share my thoughts on the 17 250SX VS 19 250SXF.

Starting with the 17 250SX.
I bought this one at the start of 2018 and put 70 hours on it.

I won't get too much into the bike in stock form as there is a lot of information around which i believe is pretty spot on. It had a decent amount of mods on it for 60 hours so that's where my experience lies.

In stock form i found it fell flat on it's face at high rpms, had finicky jetting/fouling issues and i just couldn't get it to turn that well. Not taking away anything from the bike in stock form, i still found it to be superb, it just took a lot of modding along the way to get it to where i felt comfortable.

Mod wise i had a full pro circuit exhaust, v force 4 reeds, two stroke performance head/jetting spec, pwk 38 carb conversion, WP spring conversion and racetech gold valves front and rear.

This bike ran crisp and had plenty of smooth power from bottom to top. I could ride this in 2nd/3rd gear for most of the track, the power plant was still fairly aggressive but somewhat smoother/broader/stronger everywhere. I always had trouble finding rhythm on this bike, too hot/cold into and out of corners, too hot up to jumps, i could never just find any consistent rhythm on this bike, i would get 2-3 good perfect laps in a row and then just loose consistency.

Handling wise, i found it handled well but always had a natural cornering tendency to trace out wide arcs which naturally led me to take the outside lines. No issues sticking in an inside rut, just look a little effort to turn in.

Enter the 2019 250SXF.

I had just sold my 18 RMZ 450 which i had owned at the same time and found a cracker deal so i thought why not. I literally unbolted the forks, shocks, my favorite half bent bars and bent levers off the 250SX and bolted the right up to the SXF and took it to my local track.

All i can say is what a bike! Holy shit! This thing turns and pivots on a dime, not overly sure as to how as it is literally the exact same suspension/settings and frame geometry as the 250SX. I find that i can pick any section of the track, put it on the limiter, lean it over and go for it. The updated ergos are a welcome touch also, much slimmer and comfortable feeling.

Engine wise i find it has plenty of bottom/mid to cruise around the track in 3rd gear or shift between 2nd/3rd/4th and let it eat. I can't believe how far high it revs and how much power it puts out, but at the same time it's so smooth that you can hit the throttle early mid corner and launch out of it. It certainly takes a different no fear riding style to rev it till it sounds like it's going to shoot the piston out the top but i definitely don't agree with it being a 'top end motor only'.

The only change i've made is 2 up on the rear sprocket to help utilize 3rd gear a bit easier.

At the end of the day i seriously believe my new 250SXF is as fast or faster than my 250SX.
6
3
|
Mikey150
Posts
23
Joined
1/29/2021
Location
Sydney, AU
1/31/2021 2:09am

6
3
#434
Posts
1912
Joined
3/23/2017
Location
DE
1/31/2021 2:30am
I‘ve never ridden a 250 twostroke, but man the 250fs have come a long way since my 2001 Yamaha! Even if you allow 250 twostrokes in the 250 class, no team (except for a sand race maybe) would use the twostroke. On one lap the twostroke maybe faster, but the consistency and controllability just makes the 250f a better race machine.

Handlingwise I think the engine brake helps your 250f to be better at turn in.
1
Mikey150
Posts
23
Joined
1/29/2021
Location
Sydney, AU
1/31/2021 2:40am
I’ve spent most of my riding time on 250 2 strokes but you’re right, it’s definitely blown me away with how far 250 4 strokes have come.

I guess at the end of the day it’s probably 50hp on the 2 stroke vs 40hp on the 4 stroke but I feel you can definitely put more power down for longer on the four stroke.
CPR
Posts
7115
Joined
10/4/2018
Location
AU
1/31/2021 2:50am
Four strokes are easier to ride #revelation
2

The Shop

#434
Posts
1912
Joined
3/23/2017
Location
DE
1/31/2021 3:12am
Mikey150 wrote:
I’ve spent most of my riding time on 250 2 strokes but you’re right, it’s definitely blown me away with how far 250 4 strokes have...
I’ve spent most of my riding time on 250 2 strokes but you’re right, it’s definitely blown me away with how far 250 4 strokes have come.

I guess at the end of the day it’s probably 50hp on the 2 stroke vs 40hp on the 4 stroke but I feel you can definitely put more power down for longer on the four stroke.
Yes, the power is so broad! Especially the SXF. On so many parts of the track you can just skip the upshift and rev the bike out to the next breaking zone. Saves time and reduces mistakes.
And it’s the same power (especially since efi) everytime. You know exactly how much power the bike will make when you get on throttle. For me the predictability is the biggest advantage.
1
nascarnate326
Posts
3008
Joined
11/3/2014
Location
Charlotte, MI, USA
1/31/2021 3:34am
CPR wrote:
Four strokes are easier to ride #revelation
I used to care about being fast.

Now I care about having fun.

250cc two stroke in my future.
15
1
#434
Posts
1912
Joined
3/23/2017
Location
DE
1/31/2021 3:40am
CPR wrote:
Four strokes are easier to ride #revelation
I used to care about being fast.

Now I care about having fun.

250cc two stroke in my future.
That’s why I ride 125s!
16
1
Mikey150
Posts
23
Joined
1/29/2021
Location
Sydney, AU
1/31/2021 11:40am
CPR wrote:
Four strokes are easier to ride #revelation
I used to care about being fast.

Now I care about having fun.

250cc two stroke in my future.
Sky high at 14000 rpm is my new future, 16000 rpm rev limiter model in the future would be a nice touch.
1
Leeham
Posts
1159
Joined
10/29/2018
Location
Rochester, WA, USA
1/31/2021 11:59am
I went from a 17 250 SX to a 19 CRF250R. Polar opposites lol. KTM had hard hitting low to mid and the Honda had really low power down low but pulled nice mid to top. I was much much much faster on the 250F. Went from max 10 min motos to 20 minutes. But both pale in comparison to my new 21 YZ250F.
5
kage173
Posts
3067
Joined
11/27/2015
Location
USA
1/31/2021 12:02pm
Good review. I like how you describe always coming in too hot or cold. I found that an 11oz flywheel my 2012 made it a lit smoother and more predictable but definitely lost the grunt of the motor. Which spring did you run on the powervalve?
1
1
usp4u
Posts
587
Joined
3/25/2011
Location
Karns City, PA, USA
1/31/2021 12:04pm
#434 wrote:
I‘ve never ridden a 250 twostroke, but man the 250fs have come a long way since my 2001 Yamaha! Even if you allow 250 twostrokes in...
I‘ve never ridden a 250 twostroke, but man the 250fs have come a long way since my 2001 Yamaha! Even if you allow 250 twostrokes in the 250 class, no team (except for a sand race maybe) would use the twostroke. On one lap the twostroke maybe faster, but the consistency and controllability just makes the 250f a better race machine.

Handlingwise I think the engine brake helps your 250f to be better at turn in.
Except when Benoit won the Canadian 250 National Championship on a 250sx
3
Cammy41
Posts
46
Joined
12/4/2020
Location
GB
1/31/2021 12:32pm
For smaller riders maybe a 250f would be easier to ride but in my experience they are not faster
Try a 250f against a 250 2 stroke in the sand the difference bigger than you think...
You can make an argument for either because this sport is so dependant on rider and what suits one guy may not suit another
4
1/31/2021 3:04pm
I've partially been converted to the dark side. Rode only two strokes my whole life up until last year when I traded my YZ250 for a YZ250f. I really fell in love with it after getting used to the engine braking.
#434
Posts
1912
Joined
3/23/2017
Location
DE
1/31/2021 3:09pm
#434 wrote:
I‘ve never ridden a 250 twostroke, but man the 250fs have come a long way since my 2001 Yamaha! Even if you allow 250 twostrokes in...
I‘ve never ridden a 250 twostroke, but man the 250fs have come a long way since my 2001 Yamaha! Even if you allow 250 twostrokes in the 250 class, no team (except for a sand race maybe) would use the twostroke. On one lap the twostroke maybe faster, but the consistency and controllability just makes the 250f a better race machine.

Handlingwise I think the engine brake helps your 250f to be better at turn in.
usp4u wrote:
Except when Benoit won the Canadian 250 National Championship on a 250sx
True. However it’s Canada, eh?
1
2/1/2021 10:50am
crazy i rode the same bikes yesterday i’ve got a 17 sx250 with a kehien carb and a pc slip on and rode my friends 19 sxf250 on the weekend. the 4 strokes power was just so much higher in the rpm
it was hard to get used too and it would fall on
it’s face on a steep up hill in the track once i rode it a while i got used to it and it handled better but felt heavier... for me it’s jsut the lack of low end grunt and the weight but the 4joke wasn’t as bad as i thought!
YZed250
Posts
1365
Joined
11/9/2014
Location
Costa Mesa, CA, USA
2/1/2021 11:13am
I had a 2017 250SX and a 2017 FC250 and now I'm on a 2017.5 250SXF.
I put 100+ hours on the 250SX and 30 hours on each of the four-strokes.

I know that for how I ride and how much I ride, the 250F is where I need to be for the results I want. They are all awesome bikes, and each have their own strength. There is no one 'best bike' for everyone and the results are not hugely different for me, but are definitely more in favor of the four-stroke for me.

I just feel stoked that I get to choose and I get to ride/race these amazing bikes.
1
ktmdan
Posts
1227
Joined
4/1/2008
Location
Houston, TX, USA
2/1/2021 11:17am
Did the 17 SX have the counter balancer or was that new in 18? That’s a game changer for me.
1
Leeham
Posts
1159
Joined
10/29/2018
Location
Rochester, WA, USA
2/1/2021 11:20am
Cammy41 wrote:
For smaller riders maybe a 250f would be easier to ride but in my experience they are not faster Try a 250f against a 250 2...
For smaller riders maybe a 250f would be easier to ride but in my experience they are not faster
Try a 250f against a 250 2 stroke in the sand the difference bigger than you think...
You can make an argument for either because this sport is so dependant on rider and what suits one guy may not suit another
Obviously sand it going to be a disadvantage for the 250F. You can go just as fast on either bike, just one may be easier for conditions. Dry/hard pack, 250F all the way. Super deep loam/sand, 250 2 Stroke
Mikey150
Posts
23
Joined
1/29/2021
Location
Sydney, AU
2/1/2021 11:56am
kage173 wrote:
Good review. I like how you describe always coming in too hot or cold. I found that an 11oz flywheel my 2012 made it a lit...
Good review. I like how you describe always coming in too hot or cold. I found that an 11oz flywheel my 2012 made it a lit smoother and more predictable but definitely lost the grunt of the motor. Which spring did you run on the powervalve?
I ran the yellow and 1.5 turns out most of the time, I actually really liked the green spring also, it gave it a little less abrupt hit and then more of a rising curve into the top end.
1
Mikey150
Posts
23
Joined
1/29/2021
Location
Sydney, AU
2/1/2021 11:58am
Cammy41 wrote:
For smaller riders maybe a 250f would be easier to ride but in my experience they are not faster Try a 250f against a 250 2...
For smaller riders maybe a 250f would be easier to ride but in my experience they are not faster
Try a 250f against a 250 2 stroke in the sand the difference bigger than you think...
You can make an argument for either because this sport is so dependant on rider and what suits one guy may not suit another
You’re right, once you get into that power sapping sand or deep loam there’s a big difference where the 2 stroke seems to dig in and then sail over the sand.
Mikey150
Posts
23
Joined
1/29/2021
Location
Sydney, AU
2/1/2021 12:03pm
crazy i rode the same bikes yesterday i’ve got a 17 sx250 with a kehien carb and a pc slip on and rode my friends 19...
crazy i rode the same bikes yesterday i’ve got a 17 sx250 with a kehien carb and a pc slip on and rode my friends 19 sxf250 on the weekend. the 4 strokes power was just so much higher in the rpm
it was hard to get used too and it would fall on
it’s face on a steep up hill in the track once i rode it a while i got used to it and it handled better but felt heavier... for me it’s jsut the lack of low end grunt and the weight but the 4joke wasn’t as bad as i thought!
I suggest you look at adding a cylinder head/jetting spec from Two Stroke Performance here is Aus. Really adds some meaty power which is super easy to roll on and looks killer.
1
Mikey150
Posts
23
Joined
1/29/2021
Location
Sydney, AU
2/1/2021 12:06pm
YZed250 wrote:
I had a 2017 250SX and a 2017 FC250 and now I'm on a 2017.5 250SXF. I put 100+ hours on the 250SX and 30 hours...
I had a 2017 250SX and a 2017 FC250 and now I'm on a 2017.5 250SXF.
I put 100+ hours on the 250SX and 30 hours on each of the four-strokes.

I know that for how I ride and how much I ride, the 250F is where I need to be for the results I want. They are all awesome bikes, and each have their own strength. There is no one 'best bike' for everyone and the results are not hugely different for me, but are definitely more in favor of the four-stroke for me.

I just feel stoked that I get to choose and I get to ride/race these amazing bikes.
Perfect answer here, exactly what I think.
Markee
Posts
3669
Joined
4/15/2013
Location
Suffolk, VA, USA
2/1/2021 12:17pm
ktmdan wrote:
Did the 17 SX have the counter balancer or was that new in 18? That’s a game changer for me.
The 17 was the first with the counter balancer.
2
Cammy41
Posts
46
Joined
12/4/2020
Location
GB
2/1/2021 12:41pm
Off topic have you tried the sxf350?
Both the ‘15 fc350 and ‘19 sxf350 i tried left me really impressed each time
Really nice amount of power without being overwhelming at times (imo) like a 450 can be
Seemed to thrive in the sand in places the 250f was lacking (again, in my opinion... im 225ibs so not exactly who the 250f is aimed at)
Derpin' DJ
Posts
6416
Joined
5/27/2011
Location
Newcastle, AU
2/1/2021 2:20pm
Regarding the stock carb on the 250SX, I had the two stroke performance head mod, slide mod and jetting done. Still had jetting issues. Ended up coming across that the block gasket is prone to warpage pretty early on. Pulled apart, sure enough it was warped. Replace with an aftermarket one, and it's been great ever since.

https://youtu.be/xAhsn8RJcCQ

Post a reply to: 250SX VS 250SXF my experience

The Latest