Slavens S3 Head Review

I have been using the Slavens S3 Head for over a year now. It is a high compression head for 2 stroke dirt bikes. It's specfically designed for KTM and Husky 250s and 300 2 strokes bikes. It's a bolt on modification that is pretty easy to install, at home, in your garage. The only special tool you would need to install this is a torque wrench for your head bolts.

[@mrjarjar1018]

i'm still amazed by the quality of these video's with this amount of subs, really good channel i hope you grow quickly!

[@DirtBikeChannel]

+mrjarjar1018 Well... make sure to share it :)

[@DirtBikeChannel]

***** I agree with you. Sometimes I look at all the work I'm putting in here, and think that I'm in the wrong genre with how slow the growth is compared to other genres/channels on KZbin. Then again, dirt bikes are the only thing that I'm passionate enough about to keep this up. You have no idea how much comments like yours help to keep me going. The fact that many people out there are enjoying the content and getting value out of it keeps me going. Thank you for taking time to let me know you appreciate the many, many hours of work I'm putting into this project.

[@mrjarjar1018]

+Dirt Bike Channel will keep supporting you :) i hope dirt bike channels like you gain popularity , i dont own a dirtbike but i still enjoy the content

[@boss302gorie8]

your doing really good vids kyle,they are entertaining and informative,greetings from a 300 EXC rider from australia, if you ever come to melbourne ,victoria come for a ride

[@biggbruce123]

I just got mine for Christmas. slavens racing was great to work with. it turns out the ktm, husky and beta all have the same fitment. so I went with the blue one for the bling factor on my 14, beta 300 racing. I have not installed it yet. It would be depressing to not be able to ride because of all the snow. great channel by the way kyle! my favorite video so far is the being courteous to others on the trail, we need more people to understand that, so we stop loosing off-road rights. and much respect for the trail discrepancy. I agree these areas should be earned by rider exploration. not by social media exposure. keep up the good work.

[@DirtBikeChannel]

+jake desmond Thanks for having my back on not giving up all the riding locations! When I had like 10 subs, it was different. Now, with over 16K subs, I'm not giving up trail locations any more.

[@tomstephens5024]

I have the high compression head on my 2017 KTM 300 xcw. I ride from Death Valley to 9,000'. I use race gas and it works fine at all altitudes. I've been forced to run pump gas and it still ran fine. When it's ready for a new piston it starts pinging. This is the best bike I ever owned, and my first bike was a new Bultaco Matador.

[@bikersoncall]

Does it give you that ping warning with a stock oem head?

[@osimnod]

Great content, again Kyle, and excellent quality of editing. You keep raising the bar for others to match or follow. I've watched some of Slavens' postings and appreciate yours and his technical details. Keep up the excellent quality.

[@DirtBikeChannel]

+osimnod Yes, Jeff is a good source of information. I watch a lot of his stuff.

[@rwalden1999]

+Dirt Bike Channel if you ride a 300 jeff slavens is the man to go to for any info. Its nice to know that he will actually talk to customers and help you with any problem, most owners dont care.

[@benbrown4259]

best ktm 300 info vids on the net.

[@TE300_Tim]

well..other than Slavens himself of course

[@crossroadgaragellc]

Discovered this channel about a week ago. Love it, bought a Yamaha WR about 6 months ago and love the riding tips and tricks you film Kyle, you have got yourself another subscriber. Keep the videos coming. I love dirt biking too especially the endurocross style riding.

[@Klingon8585]

Kyle, I just came across your channel about 2 weeks ago and I have a 2015 Husky TE300. I am an novice rider and find your channel to have a lot of very useful information. Please do more ride videos with live commentary - I have already watched every video you have done. Cheers from BC, Canada.

[@DirtBikeChannel]

+Klingon8585 Didn't your mom tell you not to binge on questionable content? I hope to put out some more videos like that here in the near future. The main issue that I have so much snow on the ground right now. Thanks for watching.

[@Klingon8585]

Yes indeed. I am waiting for spring as well. More maintenance videos during the meantime would be good. I particularly found the video regarding jetting to be informing.

[@jetdr]

Slaven's should be thanking you for sending customers!!

[@Niellex]

I just installed mine a couple weeks ago along with the SX CDI box and I can't wait to try it. Another great video!

[@DirtBikeChannel]

+Drew George Let me know what you think of the SX CDI. I'm interested in that for sure.

[@Niellex]

Dirt Bike Channel You bet. Just need this snow to melt.

[@dennissawyer8496]

Did the snow melt yet?🤪

[@stevetdesigns]

@@Niellex DID THE SNOW EVER MELT?

[@gtenduro4195]

I own a 2011 gasgas 250 cervantes replica and it come with the S3 slaven Head (the red one). I ride at sea level up to maybe 2500 ft, i got a JD jetting kit and its jet for ~30C (~86F). I run 90-92 octane and i never got a problem what so ever, my bike run great even if a i ride at 0C (32F) this time of year. I only got a kick starter tho. My bike are known to have a lot of low end torque for a 250 and i think the S3 head play a good role for that. Hope this help !! Great vid as always Kyle, keep up the good work ! From Quebec

[@DirtBikeChannel]

+GTEnduro Thanks for chiming in.

[@davidruth1]

FYI - This head is designed ONLY for use with the SX CDI mapping and typically a 0 .4 mm base gasket. The CDI box is also available from Slavens.

[@biggbruce123]

I'm here locally maybe I'll see you in the foothills this spring!

[@DirtBikeChannel]

+jake desmond Anything could happen.

[@bikersoncall]

Needs a dyno chart, to know what we're really getting in this head, everything else is anecdotal, which isn't a bad thing, just not definitive. That's a good heads up on being sure to have the O ring to replace the old one.

[@halsimpson2543]

Man, I really enjoy your videos. Keep them coming..! Nice new shop btw.

[@DirtBikeChannel]

+Hal Simpson Thanks Hal. I plan on doing a few more videos this year!

[@orionsantilli4365]

Your videos are amazing I find myself up binge watching almost like a tv series. Can't get enough. You have my sub and anyone who asks for dirtbike help I point them in your direction. I've been riding since I could walk on my Suzuki 50 and still learn new things every video. Where are you located? Also do you sell those stickers? Would love to rep you and show some support.

[@DirtBikeChannel]

+Orion santilli I don't sell the stickers, but I do sell some shirts. www.dirtbikechannel.com/shirts/

[@sxs243]

great videos man love the tech content! keep up the good work, you got another subscriber

[@DirtBikeChannel]

Thanks Josh.

[@bradsanders6954]

I think every mod made can help and or hurt in one way or another. A stock late model 300 of any brand can run really,really well if only tuned properly........................Higher compression doesnt usually make an engine last longer. I wouldnt do mods just cause the internet says its needed.

[@fredericjordan7233]

Thanks for the review, that's super handy actually! These videos helping us making the right choices for mods, that's appreciate. You have done so many mods on your bikes, i wonder witch one you enjoy the most, the one you have more bang for your buck. I'm thinkin about your lectron carburetor for instance or riding tubeless. what's your must? thanks

[@DirtBikeChannel]

+Frederic Jordan The one that I think is my favorite and the ONLY one that I don't want to go without is TuBliss on front and rear.

[@mobgma]

MOAR! MOAR! Keep em' coming!

[@DirtBikeChannel]

Patience my son :)

[@reedjesse]

great video very informative keep up the good work

[@kirknelson3020]

Getting ready to put new piston and rings in my bike and thinking about adding this head . Thanks for the review! Out of curiosity how often to you freshen your top end (hours/miles)?

[@enduroracer5883]

How is this a "Slavens" Head? Looks to me like it's a S3 head. If Jeff Slavens worked with them, that's fine but S3 is the manufacturer from what I understand, correct?

[@duken4evr]

Jeff claims the compression ratios and squish dimensions on the S3 heads he sells are proprietary. Jeff's prices are right there, so that is good enough for me. Got one of these for my '18 XC300.

[@ReeceTasker]

2 of my buddies bought these Slavens heads in blue for Husqvarna's TE300's, they DO offer more low end power and its noticeable however both of the bikes now seldom start on the E button now and require the kick. Maybe if they swapped out to Lithium batteries it may help but its a pain when half way up a crazy hill and they need to be kicked! My TE 300 is stock and starts first hit on the button every time.

[@DirtBikeChannel]

+Reece Tasker I haven't had that issue. I've never not been able to start my bike after installing this. I've had it on a 2014 KTM 300 XCW and now on this 2015 KTM 300 XC. Sounds like they need new batteries.

[@ReeceTasker]

+Dirt Bike Channel Yeah I'm thinking the same thing, just not spinning the bike up fast enough as their bikes always start easy on the kick. Lithium should be on the list after 100 or so hours anyways. Great low down power from the head though- -when you going to review the suspension ?

[@DirtBikeChannel]

+Reece Tasker I have only been out on the bike 3 times and one of them was really short (due to weather and other factors), so I'm still trying to give them the benefit of the doubt. I have to be honest, I didn't notice much of a difference.

[@corywalters6451]

now that you have run both, how does this compare to the RK Tek?

[@throttlebuff]

No reply...?

[@cameronfunke]

I was wondering the same thing. I’m not sure which one to go for

[@cogerino8687]

Thank you for the review :)

[@bikersoncall]

I don't see a rekluse auto clutch video at your home page, did you or would you do one? I'm thinking that the Rekluse is the very last think I would want to resort to, for my next bike, yet the ones I'm looking at (ktm for one..) seem to be using them, the Z start pro. If someone knows, please give me a heads up on what I'll need to revert back to stock clutch, if owner doesn't have the old parts.. Thanks..

[@Grovesq0]

Those look so nice😍😍😍

[@DirtBikeChannel]

+MrTwoShot It does give the bike a nice touch.

[@gbalkomd8950]

Kyle, I also have an S3 head with the high altitude insert. How low of altitude have you ridden your bike with it? I've heard that the bike will overheat as you go down.

[@DirtBikeChannel]

+gbalko Md I've ridden it at 3000 feet without any issues.

[@bikersoncall]

I have volume up full here to be able to hear you, I went to your channel and the default premier video volume is 37.5 times louder if that is even possible, cats, dogs, birds, chimps, and Kodiak bear all jumped out windows or straight through walls...

[@bikersoncall]

Does this have a noticeable benefit at around 500' or less altitude, low end mid range torque?

[@tombba]

Hi Kyle,Can"t see if you said you had a problem with e-start or not with the S3 head.Taking your rec. on the Turbine core silencer and either the Fatty or Gnarly header.Do you think with the increase in low end with the S3 I"d be better off with the Fatty to have a nice combo of lowend and broad overall power with the S3 and Fatty respectively or...go for the "max" lowend with the S3 and the Gnarly? Thanks!

[@DirtBikeChannel]

+tombba No problems with e start after installing the S3 head on either bike that I have used it on. To be honest, I haven't used the Fatty pipe. I have only used the Gnarly. The Gnarly is a good pipe.

[@Sahkopekka200]

HI! Would there be any benefit in machining my Husqvarna WR300 2009 300c stock cylinder head with compression of 6.9:1 to a higher compression? Would I gain low end or lose top end? I have the Gnarly pipe but for a 300c having only 45HP makes me wonder If I can do something to make this even gruntier? The horsepower number above is not a dyno test resault of MY bike, but a test made by somebody else on the internet on the same bike. Maybe they had it running bad...what numbers should I expect?

[@MaurizioNardi]

Hi, Is it OK on the 300 TPI too? but then you have to remap the ecu or can you start right away?

[@sammyscrap]

Sure do look cool

[@DirtBikeChannel]

+Tosh Outdoors Adds a little bling for sure.

[@micar1000]

did you put this head on before you changed the carby over to the letron? Did you have to change the jetting in your carb for the new head?

[@DirtBikeChannel]

+mike.k Installed the head first. No, I didn't have to change anything on the carb.

[@bobbyorrfan4449]

Could you please make a video on what you do for your regular maintenance on your KTM

[@DirtBikeChannel]

+Bobbyorrfan444 I'll put that on my list of video topics.

[@jwbadassc10s10]

Do you know of a upgrded cdi box i spoke to Eric gora from eric gora racing he told to change the cdi box from a 300xc box to i think he said a 250sx box he said it will give more power at all rpm range s have you ever heard anything like this

[@MW-gh3lt]

Jasoñ Willis Yes that is common. I've never heard of putting the 250 on a 300 but putting a 250sx cdi on a 250xc or 250xcw is normal, especially with this head

[@user-lu1lo6gr1d]

What kind of gasoline do you use with this head? 95, 98, 100? I mean octan number.

[@rminecraftsteve]

I've heard that if your change your gaskets or in any other way increase compression, you should use a higher octane fuel to prevent/reduce engine knocking. Any comments on that? Thanks

[@DirtBikeChannel]

+rminecraftsteve I'd talk to the machinist that is doing your motor in this specific case you are talking about. A good machine shop will be able to help advise you on exactly what gas you should be running. They would give you a much better answer than anyone (including me) online. These Slavens heads are "bolt on" and you aren't changing the "Squish band" or compression enough to warrant a change in fuel.

[@rossheaver934]

Hey Kyle I'm just about to start setting up my 2016 300exc for the new season and I'm looking at both the Slavens and R-TEC heads, any advice on which one to go for? I ride between 3-5 Hour enduro and the odd MX. I will be running the FMF factory fatty with the the Turbine Core 2...any advice would be great. Cheers Ross.

[@DirtBikeChannel]

Hi Ross, rather than do this publicly, can you email me directly at [e-mail]?

[@TheOfficialKC]

Ross Heaver S3 is about $100 cheaper. Jeff Slavens is 100% focused on rocky single track, low speed technical riding. RK-Tek will build you a custom insert for whatever altitude and riding conditions you have. RK's head design is patented, though I can't say I've seen any comparison dynos. Word is, they are better though. Both will be good, price difference, 2 inserts with S3, so comes down to what you want and what you are willing to pay.

[@bartskin9147]

just came across your channel I am looking at a 2 stroke ktm i sold my 2001 xr650r uncorked about 3 years ago and want to get back into the sport would you recommend a 200, 250, or 300cc bike my skills aren't the greatest looking to do some hare scrambles and like the electric start, geared up i weight about 245 lbs. I was able to keep up with my buddy who rode crf450x with the big red pig so I am not a complete nubbie just want something light weight and not on steroids if you just burp the throttle let know what you recommend Thanks Bart

[@DirtBikeChannel]

+Bart Nelson At your weight, I'd look for the 300. It will have a bit more torque than the 250 and the 200, so that will come in handy.

[@blakemitchell4572]

Great Channel

[@DirtBikeChannel]

+Blake Mitchell Thanks Blake!

[@DavidGarcia-jw1df]

I just caught your video, thanks for the updates and the info., but I was wondering if Slavens makes the S3 for GasGas, any ideas? Again, thanks.

[@DirtBikeChannel]

I don't know...

[@TheOfficialKC]

David Garcia Slavens himself only works on KTM 250/300. S3 may have a GasGas head. I'd check their website. They do a lot of trials stuff too so I bet they have a GasGas head.

[@chadhobson3225]

so I've heard that V actually help increase fuel mileage? is this the case have you noticed your being able to go farther on a tank?

[@DirtBikeChannel]

No, I haven't noticed that.

[@theDugonator]

Where do you buy race fuel?

[@toadamine]

Joe Mamma search online, it's available at many local fuel suppliers nationwide.

[@Preflightterror4]

You can buy race fuel at the race track...

[@LtCatfish]

Joe Mamma Sunoco if you have one around you

[@milosbgd]

Hi, Is there anything else you should replace (spark plug, CDI, jetting, exhaust) and Please which kind of FMF you have on this pretty bike, I appreciate the answer. Tnx!

[@DirtBikeChannel]

+Milos Zivkovic You don't need to change anything else when doing this. I have the FMF turbine core 2 silencer on here. If you are asking about the header pipe, it's the FMF Gnarly pipe

[@milosbgd]

+Dirt Bike Channel , thanks for the tip, Cheers

[@wadoktm5316]

You said the S3 head gave the bike more snap off the bottom, would you say the power delivery is still smooth? could you pull a higher gear on hills etc?

[@DirtBikeChannel]

+WadoKTM yes, it's still pretty smooth on the power deliver. Not as smooth as stock, but that is sort of the point of this head. Not sure it gives you an entire gear on a hill. I wouldn't say that.

[@wadoktm5316]

+Dirt Bike Channel would say its too much of a handfull in tight technical stuff?

[@DirtBikeChannel]

+WadoKTM No, it's not bad. It will stall a bit easier with the higher compression. Generally not an issue though.

[@jacobwhittaker9749]

is there any problems with detention?

[@DirtBikeChannel]

+Jacob Whittaker Well.... funny you mention it. Just got back from a ride where we were only 3k feet above sea level. Has a fair amount of detonation and had to run octane booster to clean it up. Would have been much better with the low altitude insert for that ride.

[@Kolsch221]

How does it work with the Lectron carb?

[@julianwilson5174]

What's best for overall grunt and bang for buck. Fmf gnarly header, silencer or head

[@DirtBikeChannel]

+julian wilson Bang for the buck...Silencer first, then it's toss up on the header of the head.

[@loreighter888]

nice video as always! is there something similar for a 125 exc?

[@DirtBikeChannel]

+loreighter888 Not from Slavens but other manufactures surely make something.

[@loreighter888]

+Dirt Bike Channel thank you!

[@tjallaballa]

BUD racing makes one :D

[@riptripper1627]

can you do a sx cdi review together with the head i think you gonna gain abit more power from that :) cheers

[@evanroper7542]

pls can you do a video on how to assemble it

[@JF32304]

where do you ride? I'm assuming you're in Colorado. ....

[@DirtBikeChannel]

+Jesse Fritz Utah.

[@Augis3de]

i want KTM so bad :(

[@LtCatfish]

Augi58 tbh I like my bike, a couple of upgrades and it’s perfect You can see it on my channel

[@ACDCRD]

Do you know any performence heads for a 2006 rm125

[@speedwobbles1523]

ACDCRD same dude I have an 04 and I'm at a loss for cool parts like this besides plastics and graphics

[@NZ2STROKE]

Does the bike run any hotter?

[@DirtBikeChannel]

No, I think it actually cools better.

[@jnuxca]

does anyone know how a stock sx 250 head will change an exc 250? i'd like to squeeze some more top end power out of my bike without spending a bunch of money (that i don't have ahahah) a used sx head can be found kinda easy and it's a lot easier mod than putting your stock head under a milling machine i guess (sorry for the poor english, probably messed up the last sentence) btw i'm talking about a 2012 model

[@greg657]

jnuxca try a pipe. fmf or pro circuit surely would have top end pipe for that bike.

[@jnuxca]

Greg Or Jen problem is a pipe costs about the same as modified head, i found out that the ktm 2 stroke models are badly jetted out of the box, tried a different needle and the powerband went all the way up, best 10€ ever spent on a bike, night and day difference for that money

[@TheOfficialKC]

jnuxca just send your head in to someone like Cycle Playground. A correctly modded head will outperform a SX head. More power and easier jetting.

[@bradsanders6954]

Higher compression can make a bike rev less,its not a mod for top end pull.

[@zskinner3235]

Do they make one for the yz250?

[@DirtBikeChannel]

+z skinner I don't think that Slavens does, but there could be others that make them for it.

[@badwizard12]

can i use pump gas with it

[@DirtBikeChannel]

+badwizard12 yes. I certainly do.

[@blakelawrence1891]

wow only 91 octane here in nz pretty much every pump has at least 95 up to 98

[@DirtBikeChannel]

+Blake Lawrence Yeah, it's because of our altitude. Since we are a mile high most of the time, the gas doesn't need the higher octane here.

[@blakelawrence1891]

Dirt Bike Channel makes sense

[@Puzkajuzzi]

They use a different type of octane rating in USA, Canada and Brazil called AKI. (Anti-knock index) In most countries (europe, AU, NZ etc.) the octane rating type is called RON. (Research octane number) 98 RON octane fuel is the same as 93 AKI 95 RON octane fuel is the same as 90 AKI

[@darrenboddy]

You gotta put links in your description for items your are reviewing for lazy farts like myself ;)

[@DirtBikeChannel]

+Darren Boddy If they would give me kickbacks, maybe I would.

[@jon...6825]

91. are fuel is 99

[@hreindustries]

great vid but u need to fix that mic noise in the back round.

[@DirtBikeChannel]

+m1ke2001 Is that why you dis-liked the video?

[@thatguywhoridesyzs9627]

+Dirt Bike Channel this guy must be a mic critic

[@DirtBikeChannel]

+Clayton Ledford Has to be :)

[@hreindustries]

+Dirt Bike Channel i didnt dis like the video

[@hreindustries]

+Clayton Ledford no it just bugs me because i wear head phones.

[@user-os9zl3qz8k]

좋은 정보다 한번 사용해 보고싶다 ktm 2016 식스데이즈(300exc)를 소유하고 있다 더 좋은 정보 부탁합니다

[@shanecodman1842]

Huh?. Flat earth

[@tristan7331]

i have 98 octane running

[@Lolvids39]

$220? Jesus does this guy think I just won the powerball?

[@DirtBikeChannel]

+Shane Yes, and since the power-ball lotto is 1.3 billion right now, you should have money to burn. If on only reviewed things that were free, you probably wouldn't watch :)

[@JPetusthrottletherapy]

dude, sweet video's, i like the non bullshit straight to the %$@#$% point. me - 2012 ktm 300xc with all kinds of farkles and do dad's. Recluse- yes i'm more of a pussy rider, as my buds would say- does that recluse come with panties??? ..... i love my recluse, it allows me to not worry about clutch when i'm focused on az mtn riding- crown king, boulders, crested butte, etc. etc.... can you, or have you done a vid on recluse???? i want you to do one, cause you will tell it like it is, or like my friends say what a recluse is

[@jon...6825]

wtf is race fuel????

[@justinf6758]

Something like vp fuels

[@jon...6825]

Justin F lol we have hi octane 99. In the usa it's 92????? Haven't a clue I'll ask can you get it here? If so I'll buy it all the time.😁😎😎

[@justinf6758]

+John OReardon it varies. And it's super expensive and from I hear it doesn't really do much if you don't need it because of engine work.

[@justinf6758]

+John OReardon and I don't know where you live so I have no idea if it's not some 3rd world country then I bet you could get some form of race fuel don't know if it would be vp though. Vp is the most popular in the US

[@jon...6825]

Justin F I live in Ireland. Europe and I've never heard of race fuel but are fuel is so expensive lol we get it in litres. We're getting ripped off big time.... €1.30 A LITRE.....

[@offroaddutch]

Only 91 octane, I hav 97/99 octane at nearly every fuel station

[@DirtBikeChannel]

+offroaddutch Then use that.

[@zaphodpeters]

+offroaddutch You must be closer to sea level, because as you go into Colorado, Utah and most other mountainous states, the highest octane pump fuel will decrease to 91, I believe they are compensating for altitude, since air density has also decreased.

[@DirtBikeChannel]

Zaphod Peters Agreed.

[@georgeboswell4620]

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