I did the carb, pipe, and reeds on my 09 250xc. What a difference!! I installed the red power valve spring as well. Head is next but this thing came alive after the upgrades I did already. Thanks for the video. Keep up the good work
Thanks. Jeff, for all the great recommendations on these bikes. I aslo appreciate you putting in the pitch for riders to join a club or organization that fights to preserve OHV opportunities. As a founding member of the Blue Ribbon Coslition, the Idaho Falls Trail Machine Association, and two snowmobile clubs, I have been preaching and recruiting since 1981. Too many riders believe that if they do join, our battles will be over in a year or two. Everyone needs to realize that their help is needed eternally and they are involved in this fight whether they want to be or not. Thanks again, Jeff.
In 2014 I did the S3 head, SXS CDI and eventually (after destroying the stocker) FMF Fatty on my 300 XC-W. The bike came with VForce reeds and a Keihin carb stock. I have to agree that the head and cdi are well worth the investment. I’m building my 2019 300 XC now, in phases as I have time to play. Stock, the bike was really off, and after some carb tweaks I was able to ride it around the yard. I then added only the SXS CDI and the throttle response is amazingly better. I have bought the S3 head and plan to upgrade the reeds for reliability. It’s a shame KTM went away from Keihin. With how reliable, consistent and low maintenance my 2014 was, I can only hope the 2019 performs as well.
Thanks Jeff for another great video. I did these exact same mods on my son's 17 250XC and (except for the Lectron carb) on my 2010 250XC with very good results. I recently picked up a new 2019 250XC, so am looking forward to your video on that one. The sooner you post it, the sooner I'll be buying the parts from you!
Eric Gore cylinder porting is a great way to alter power band to your liking. Suspension is the number one worst thing on a KTM that needs to be fixed (still). The Lectron is too cool, lots of people getting great results with them.
This is coming from another angle....I've got a xc 300 2018 carburetor. So it's used for motocross. The mods I've done are....deb pipe and silencer. Had a go with them v force reeds . But they kept breaking. So a rad valve was used. Jd jetting kit. And the rear shock. A bladder kit. Now it pulls like a team of horses ... well happy with it
Hi Jeff, Thanks for all the information in your Videos! It really helps to hear it from a true expert. I currently have a 17 250SX I use mostly in the woods and trying to figure out how to make it lug more like a 300XC. Looking to see if your S3 Head works on a SX and what it would change. It is stock with a Fatty Pipe Thanks Will
Jeff - Would you offer any advice on any mods possible on Paramotor two cycle motors? I fly a 280 cc Air Conception Tornado 280 motor. It has a WALBRO 37C carb. How does one evaluate whether head mods or porting would improve this engine. Principal complaint is rough mid-range performance. Cruise is 5100-5600 rpm. Max rpm is 7400-ish. Midrange in the 4200-500 rpm is rough.
I have been riding the venerable KTM 300 2stroke for over 10 years now, and the latest one I bought, a '13 300XC had such a strong engine (even over my last '13 300XC, which I put over 400 hours on), I finally figured out what made it so different: it turns out the previous owner installed a JD jetting needle! Love it..
@@slaverace1 lol what a question hey!!! Slavens are good to go, I made an australian purchase and honestly it was surprisingly fast, Installing and testing after the rain clears. But will be great
Hey guys, checkout out our new video on the Top 5 Performance Engine Performance Mods for KTM and Husqvarna 250s and 300s. Here are links to the products in the video. slavensracing.com/shop/slavens-mule-high-compression-component-cylinder-head/ slavensracing.com/shop/slavens-mule-hv-lectron-17 slavensracing.com/shop/fmf-fatty-2-stroke-pipes-ktm-husaberg/ slavensracing.com/shop/vforce-4-reed-valve-system/ slavensracing.com/?s=SX+CDI+unit
I did the carb, pipe, and reeds on my 09 250xc. What a difference!! I installed the red power valve spring as well. Head is next but this thing came alive after the upgrades I did already. Thanks for the video. Keep up the good work
Thanks. Jeff, for all the great recommendations on these bikes.
I aslo appreciate you putting in the pitch for riders to join a club or organization that fights to preserve OHV opportunities.
As a founding member of the Blue Ribbon Coslition, the Idaho Falls Trail Machine Association, and two snowmobile clubs, I have been preaching and recruiting since 1981. Too many riders believe that if they do join, our battles will be over in a year or two.
Everyone needs to realize that their help is needed eternally and they are involved in this fight whether they want to be or not.
Thanks again, Jeff.
I appreciate it too, we are having to fight more for our places to ride now up here in Canada and joining the groups helps.
In 2014 I did the S3 head, SXS CDI and eventually (after destroying the stocker) FMF Fatty on my 300 XC-W. The bike came with VForce reeds and a Keihin carb stock. I have to agree that the head and cdi are well worth the investment. I’m building my 2019 300 XC now, in phases as I have time to play. Stock, the bike was really off, and after some carb tweaks I was able to ride it around the yard. I then added only the SXS CDI and the throttle response is amazingly better. I have bought the S3 head and plan to upgrade the reeds for reliability. It’s a shame KTM went away from Keihin.
With how reliable, consistent and low maintenance my 2014 was, I can only hope the 2019 performs as well.
I agree... what got into the mind of the people at KTM to leave the Keihin behind. Bad mistake.
“Really off” I’m on a 19 300xc and man is that an understatement. JD kit helped a lot, but I’m still looking to find the KABAAAM of my old 15.
STIC Metering block!!! I'll be testing mine when the snow melts ('17 300).
Thanks Jeff for another great video. I did these exact same mods on my son's 17 250XC and (except for the Lectron carb) on my 2010 250XC with very good results. I recently picked up a new 2019 250XC, so am looking forward to your video on that one. The sooner you post it, the sooner I'll be buying the parts from you!
good content. i only disagree with the carb change, my mikuni with the graham jarvis mods on it is absolutely phenomenal
What were your carb mods?
Good mods, though I would swap out the mukuni for a keihin air striker any day over a lectron.
Eric Gore cylinder porting is a great way to alter power band to your liking. Suspension is the number one worst thing on a KTM that needs to be fixed (still). The Lectron is too cool, lots of people getting great results with them.
Thank you Jeff for sharing your knowledge.
You said to use an SX CDI. So when I have a 300 EXC i use a 250 SX CDI?
They make a 300SX kit for the 250SX that comes with a unique 300SX CDI.
What is your opinion on fly wheel weights for harescrambles?
This is coming from another angle....I've got a xc 300 2018 carburetor. So it's used for motocross. The mods I've done are....deb pipe and silencer. Had a go with them v force reeds . But they kept breaking. So a rad valve was used. Jd jetting kit. And the rear shock. A bladder kit. Now it pulls like a team of horses ... well happy with it
Hi Jeff, Thanks for all the information in your Videos! It really helps to hear it from a true expert. I currently have a 17 250SX I use mostly in the woods and trying to figure out how to make it lug more like a 300XC. Looking to see if your S3 Head works on a SX and what it would change. It is stock with a Fatty Pipe Thanks Will
Jeff, would you recommend similar mods for the pre-17+ 250/300 XC’s like the 16?
Jeff - Would you offer any advice on any mods possible on Paramotor two cycle motors? I fly a 280 cc Air Conception Tornado 280 motor. It has a WALBRO 37C carb.
How does one evaluate whether head mods or porting would improve this engine. Principal complaint is rough mid-range performance. Cruise is 5100-5600 rpm. Max rpm is 7400-ish. Midrange in the 4200-500 rpm is rough.
Sorry, not familiar with that engine but rough running sounds like a fueling issue, too rich in the mid-range.
Jeff, do you have a head recommendation for the 150s? If so, what is the rule of thumb for octane rating vs compression vs squish band clearance?
It is odd that Jeff hasn’t commented, he might not like them, I just got a 19 150te.
Jeff, a.re the CDI units all different for the KTM SX, the XCW, and the XC? Different between the 250 and 300 also?
Jeff, if I add an SX cdi, should I expect to need to adjust my Lectron? (I have a high compression head & gnarly pipe on my 17 3-0 xc-w. ) Thanks.
No. Just install and enjoy.
Is there any additional benefit going with the SX CDI on an XC? I thought they were the same.
I switched to the sx cdi box on my 17 xc and it seemed to help. It goes well with the slavens s3 head and a kehein carb.
Wondering if there's any premature wear and tear on motor with the high compression head-have always heard engine mods are bad in this regard
Definitely no premature wear.
best ways to add some bottom end on my 2002 KTM 300 MXC? would a performance head help?
Heads are not available for your year model but you can send your head to us to be machined.
Jeff, what are your thoughts on needles? I have a JD jetting needle in my bike and love it!
JD Jetting kits work awesome not everyone wants to / has the money to spend 100s on a lectron carb
GoViking
If it works for you, gets you out riding with your buddies, I’m all in. We sell a lot of JD kits and hear mostly positive feedback.
I have been riding the venerable KTM 300 2stroke for over 10 years now, and the latest one I bought, a '13 300XC had such a strong engine (even over my last '13 300XC, which I put over 400 hours on), I finally figured out what made it so different: it turns out the previous owner installed a JD jetting needle! Love it..
Jeff - How would a 1982 Husqvarna 250XC compare with a KTM 250SX?
Basically the same bike 🤣🤣🤣
Where can I find a performance head for my 2020 ktm 250sx
SX models already have a high compression head.
Jeff Slavens thank you
👍...thanks, Jeff!
Are U putting on kick starter on 2022 XCW 300
No.
Would all those mods apply to a 2013 Husaberg TE250 ?
Yes
Don’t you use the clutch wheith?
Got a 2019 300 XC and wondering where I can get the SX ignition box?
Where else? The KTM candy store. slavensracing.com/shop/sx-cdi-unit-for-ktm-husaberg-husqvarna-300/
@@slaverace1 lol what a question hey!!!
Slavens are good to go, I made an australian purchase and honestly it was surprisingly fast, Installing and testing after the rain clears. But will be great
Hey guys, checkout out our new video on the Top 5 Performance Engine Performance Mods for KTM and Husqvarna 250s and 300s.
Here are links to the products in the video.
slavensracing.com/shop/slavens-mule-high-compression-component-cylinder-head/
slavensracing.com/shop/slavens-mule-hv-lectron-17
slavensracing.com/shop/fmf-fatty-2-stroke-pipes-ktm-husaberg/
slavensracing.com/shop/vforce-4-reed-valve-system/
slavensracing.com/?s=SX+CDI+unit
Really surprised you didn’t speak of any flywheel weights?
Flywheel weights have their pluses and minuses like many products but they are not in my top 5.
Predictable with the lectron
Which power valve spring at what setting do you run on the 250/300?
Stock spring, stock setting.
Jeff, can a SX250 CDI be put on a 2014 200 xcw?
No
Any overheating or pinging issues with the high compression head?
I wouldn't use it if it caused those issues.
man that pipe hangs out alot , its about the only thing i don't like about 2bangers !