GET MORE BRAP!!! How to mill a 2 stroke cylinder head Pwc , Atv, Dirt.

In this video i show you how to mill and 2 stroke cylinder head and cut the squish. Please Watch our videos on checking squish and CCing a cylinder head so you can properly check your work after.
Thanks for watching. Please subscribe to our channel
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[@Anchor-Tractor-Man]

I've been a metal fabricator for over 37 years. I truly enjoy watching masters of their craft do their work. You definitely know your trade. Good informational content in your videos!!

[@EricksonMachinePerformance]

Thank you. Your comment is greatly appreciated. And thanks for watching

[@riimit]

FROM ITALY YOU ARE NUMBER 1.

[@EricksonMachinePerformance]

Thank you for the kind words!! And thanks for watching

[@haitzyice]

I have a 2018 KTM 250xc dirt bike. I was told by a KTM GURU that instead of buying an aftermarket head… all I had to do was: - - “You can just get the head cut locally .018-.020 is all it needs shaved off the main surface.” - - Does this sound right? I’m guessing this is in effort to make higher compression correct? How do I explain to my local machine shop what I want done? Is this considered decking it? Loved the video. And thanks so much in advance for your time. -Pete

[@chrisbenton8842]

Really good video again. Can you cut the squish on the mill with a cutter in the boring head? What squish clearance do you set the engines to? I set mine to 1.1mm is that about right?

[@EricksonMachinePerformance]

It would be difficult to get a nice cut with a boring head but you could probably grind a cutter the right angle. I have never done it that what tho. Depending on the engine and the performance wanted I set them up between. 035"-.065

[@Armilite1]

How much does it Cost to Clean up a head like you did to this? I have a Skidoo 670 HO twin head that had Detonation issues, so pitted. No by me, the guy I bought it off of. The Standard 670 1993-1999 used 11.5cr and the 670 HO 1998-99 used 12.5cr. I also have some 377F/380F Twin Heads that are 9.6cr and would like Milled for 11.5cr.

[@EricksonMachinePerformance]

Normally $80-$100

[@Jacobskibros]

I've noticed that aftermarket heads have a more half circle shaped dome. I'm assuming it's better? You got that CNC mill with a probe. Curious why you don't slap a bull nose endmill in there and 3d mill the exact dome profile you want and then flip it and cut off all the cast surface so it looks like a full billet. You know a lot of people just want to look cool. I'm guessing your just getting into programming that thing since we haven't seen erickson billet heads on here yet. I love seeing your videos!

[@EricksonMachinePerformance]

I make billet heads. For Yamaha 701/760. I have been a cnc programmer/ machinist for 19 years. It's more of a cost effective thing. It's not worth putting that much work in a stock head casting. Theres not enough metal to reshape the dome correctly and still have a strong head. Also running more then 170 psi can cause cylinder cracking.

[@vadimkargin3200]

That was amazing 👏

[@AtimatikArmy]

How do you machine the Combustion chamber dome if you need to reduce compression? Great video!

[@EricksonMachinePerformance]

By milling the head and re cutting the squish you shine the dome. In general I don't do much on the dome because many heads can be thin there

[@AtimatikArmy]

@@EricksonMachinePerformance I'm an old IJSBA racer from back in the 90's (1993 Nov 550 Limited National Champion) and my dad is helping me build up a mint 1995 550 SX I recently got. We decked the cylinder to change the port timing, but we made a mistake because even with the stock head we have super crazy high compression. I still need to machine my squish but also need to machine the domes to reduce compression. Trying to figure out the best way to do this... I have access and regularly use a Bridgeport and medium size lathe at work... Anyways, I think I might want to send my flywheel to you to get the ultralight service done sine you also balance them (something I am un sure about how to do.) But still trying to figure out what to do with my compression situation (I'd hate to to have to scrap this cylinder now, it's in mint shape otherwise).

[@EricksonMachinePerformance]

Did u mill the base gasket surfaces or the head surface?

[@josephrobinson8894]

So after cutting everything, are you keeping the cc’s the same ?? So that the combustion ratio is intact ??

[@bikersoncall]

So much more important than the right speed etc of a milling machine, would be Formulas, or how much to remove. Why this is done, (It's for added compression I guess, and maybe truing up..) So lol, what is he doing here, taking a little off the top, like a 'skilled' barber lol... and maybe a little more if you take two much off twice.. shrugs.. ''I cut it twice and it's still to short''

[@topfuelteddy]

​@@bikersoncalltotally agree, he's said on other replies he doesn't touch the domes so all of the heads he machines have completely screwed compression ratios .

[@HaMoOdPiXeLx]

Love your videos u helped me out alot and saved me alot of money keep up the good work👍👍👍

[@EricksonMachinePerformance]

Thanks For watching!

[@joverbuhok5222]

Great bro.... It will increase more compression. Right?

[@EricksonMachinePerformance]

Yes

[@joverbuhok5222]

After that... You must change bigger jettings? For carburetor

[@EricksonMachinePerformance]

In general you dont need to rejet it. You Might need a small adjustment so if your on the borderline on your original tuning maybe but normally no

[@joverbuhok5222]

Thanks bro... When is the time we need to rejet the carburetor... Like what kind of upgrades that we should rejet the carburetor?

[@wtm7554]

This is why I cut in two parts twinn cilinder head for more optimal adjustement.

[@coltholder7568]

Thanks for the video 👍

[@EricksonMachinePerformance]

Thanks for watching

[@laurentmaggio9439]

Very interesting vidéo i would like have some machine like that i rebuild Atte tvOS moment à 750 sxi thanks

[@EricksonMachinePerformance]

Cool 👍

[@deltameme8192]

can you weld combustion chamber to boost compression

[@EricksonMachinePerformance]

Yes you can BUT first you have to try not to warp the head and second you need to re machine everything. Normally the labor would be more then the head is worth.

[@mxcollin95]

Do you calculate how much to machine off of the head in order to hit a specific compression ratio? If so, how do you go about accurately calculating that? (Or would you do compression tests after machining and then machine again if you’re not at your target compression ratio?) Also, after you’ve machined in a new angle to alter the squish band, is there a certain radius you’re looking for or shooting for when you go from the part of the squish band you machined to the domed part of the head you didn’t machine? Seems like you could end up with a fairly sharp transition from the machined portion of the squish band to the non machined portion of the squish if you didn’t try to at least blend the two surfaces. Sorry, if these are dumb questions. I grew up racing two-stroke dirtbikes and engine tuning for more performance has always been super interesting and fascinating to me. Really enjoyed the video! Glad I stumbled on to your channel! Definitely subscribing 🤙

[@EricksonMachinePerformance]

I have a video how to cc head. That's how to check. The amount to remove is really gues and check till you know.

[@mxcollin95]

@@EricksonMachinePerformance I just watched that video…great stuff! 👍

[@beemerkon]

I tried to subscribe 5 times

[@rlyle5804]

How do you store a two stroke twin cylinder head? I have several spares and want them store them properly. Thanks!

[@EricksonMachinePerformance]

Store them? Do you mean head or cylinder? Cylinders coat in oil and wrap in a bag.

[@rlyle5804]

@@EricksonMachinePerformance Cylinder heads. Thank you!

[@EricksonMachinePerformance]

@@rlyle5804 heads at least on these engines are aluminum. Nothing really needs to be don't to store them

[@laurentmaggio9439]

I Want go see a spécialist for this work Thanks again for vidéo

[@EricksonMachinePerformance]

Thanks for watching!

[@tacticalwarfare8413]

Can you weld the combustion chamber for more compression ratio

[@EricksonMachinePerformance]

Technically you could but you would also warp the head considering thin they are. It's easier just to mill them down.

[@nickdilauro7118]

Where are you guys located

[@doobyboy21]

I have a 2 stroke RMK 700 2009... I'd like to bump up the compression. Can this also be done to a stock snowmobile engine ?

[@EricksonMachinePerformance]

Yes 100% we do them all the time

[@gilbertseriale8343]

Can u rework an 01 kx 125 head like this it have some pitting and how much it would cost?

[@EricksonMachinePerformance]

Yes email me pictures [e-mail]

[@albertosalvatori8666]

Impresionanteeee!!!!👏👏👏👏👏👏

[@EricksonMachinePerformance]

Thank you

[@DiyExtracts]

How much to mill the heads on 90s Yamaha 650 and do I need to upgrade anything else on the engine for this upgrade ?

[@EricksonMachinePerformance]

$85 plus shipping. Only thing u will need is a head gasket

[@EricksonMachinePerformance]

Email me [e-mail]

[@DiyExtracts]

@@EricksonMachinePerformance oh damn brother send me address and how backed up are you I might have two for you my buddy is gonna want to do his too I’m sure

[@EricksonMachinePerformance]

@@DiyExtracts email me [e-mail] Heads at the moment are about 3 weeks

[@matthewfredrickmfkrz1934]

I just feed the wife beans for the braps

[@hedgepethracing9590]

Need some work done to my cyilender. (85 honda fl350R) would you be interested if I can get it to you?

[@liamfanning_75]

My lathe only has an 11” swing, is there a way to cut squish on a mill?

[@EricksonMachinePerformance]

Yes but the lathe is the easiest. You can make an angle cutter or put on a rotary table and tilt the head. The main issue with an angle cutters it's a lot a cutter contact in its next to near impossible to get a nice cut without having chatter

[@robertmason8341]

American Pacemaker lathe👍🏻

[@EricksonMachinePerformance]

Yup!! It's a great lathe. I rebuild it 12 years ago. It's a work horse

[@lanceanderson1653]

Hi, Generally how much material do you skim off a OEM Kawasaki head on a 750 big pin for a certain amount of extra compression. I have a 98 Pro with an old MRD head (with o'rings) that I want to replace with a OEM (with gasket) head but skimmed down. I run/ran 98 Octane, I have a "Factory Pipe" and I believe the timing is advanced though not sure how much with a MSD ignition. Im a metric guy if that is any help. I dont know the compression on the cylinders until I put it back together. Im new to all this and would rather play it safe. Cheers.

[@EricksonMachinePerformance]

Do you have a lathe and a mill?

[@lanceanderson1653]

Erickson Machine & Performance I have access to one yes.

[@jonathangibbons9345]

Hello, I have a Polaris xc 500 sp, 2002 or so. Can I send the cylinder head to you so you can mill it, just enough so that it'll have a little higher compression. Where do I send it to?

[@EricksonMachinePerformance]

yes email me [e-mail] and ill be happy to help you out

[@hedgepethracing9590]

@@EricksonMachinePerformance can you send me your info so we can talk about prices for boring a jug and doing a head

[@EricksonMachinePerformance]

@@hedgepethracing9590 email me [e-mail]

[@edgardomarquez9971]

I wish I worked at a machine shop

[@EricksonMachinePerformance]

Its a great occupation. And It's never to late to start

[@RicRouch-z2r]

What's the price of machining a set of 1992 vmax-4 snowmobile heads

[@EricksonMachinePerformance]

Email us [e-mail]

[@richardroque3950]

Hey Eric I have a 650 that needs rebuilt. Is there away that you can help me I live in bullhead city AZ and I have a 1989 x2 been in the family for 31 yrs and I put about $600 in it and it ran good for 3 months and now it need to be machine work .

[@EricFB]

Send him am email. Comment section isn't your best bet if you're looking for a reply.

[@chrisgall4664]

Can you cut a single cylinder head just using the lathe and no mill?

[@EricksonMachinePerformance]

Yes no problem

[@dynodom4677]

What is the best squish value you can recommend? Given 95, 98 or 100 octane fuel (in Europe)

[@EricksonMachinePerformance]

There's ALOT that goes into it. Pistons, bore, stroke, pipe, ignition, fuel, it cN range from .035" to .08"

[@dynodom4677]

It is a relatives low power motor for an radio controlled aeroplane. 250 cc twin opposed. www.zdz.eu/inpage/zdz-250b2rv-j/ I measured 1.7 mm squish. Piston top is flat, so is the squish area in the head. Exhaust is a normal muffler not on pipe. Stroke is 50 mm, bore 56mm.

[@dynodom4677]

Oh, Ignition timing is 4 deg BTDC in idle, advancing to 28 degrees max at 4000. Max RPM 6000

[@EricksonMachinePerformance]

@@dynodom4677 there will be some rc engine videos coming. Soon, gas and nitro. For Rc planes and helicopters

[@dynodom4677]

@@EricksonMachinePerformance could you perhaps evaluate on large RC gasoline engines instead of small Methanol Motors?

[@nsant]

Is there a chart that shows how much to mill for how much compression?

[@EricksonMachinePerformance]

Nope Mill and check

[@laurentmaggio9439]

Hi i would like Knowles how Many in mm we can cut 0,25 more or - thanks

[@EricksonMachinePerformance]

It's a fairly open ended question depending on what compression you want and the squish angle you cut it to for the most part it is really guess and check

[@bikersoncall]

@@EricksonMachinePerformance What are the formulas?

[@EricksonMachinePerformance]

@@bikersoncall there isn't 1. Depending on the angle and squish that compression change. It's really an experience thing. And testing after

[@EricksonMachinePerformance]

@@bikersoncall also there's a big difference in water cooled and air cooled. And each engine h!s different requirements. This is by no means 1 size fits all. You need to test and check basically what we have done for the last 20 years.

[@bikersoncall]

@@EricksonMachinePerformance I would guess that you need the complete engine for testing... I ask all this as I'm not a machinist and don't plan on buying a mill, but I will be needing work done on my 230cc dirt bike engine hoping to bring hp up from about 17hp to hopefully 25 hp. I think stage one changes would give me about 2hp toward that goal.. seems that increasing the compression which 'might' be +- 9:1 to11+:1 might help.. shrugs...Thanks.

[@charlesdecelles9798]

How many more degree do you put on the squish than the piston ?

[@EricksonMachinePerformance]

All builders use a different angle. In general a .5°-4° more then the piston.

[@charlesdecelles9798]

Thanks !! Going to do it soon before the summer. I'm from québec so we still have snow haha. The last thing im not sure to understand is how a simple angle give clearance between head and piston. Doesn't it need to be ingrave a couple thousand like the stock dome? Sorry if i'm not totally clear emglish is not my main language ahah

[@EricksonMachinePerformance]

​@@charlesdecelles9798 it depends on the engine alot of engines the piston is Below Deck @ TDC so add that with the thickness of the headgasket and your normally over the optimal squish size. Which is why alot of modified heads that use headgaskets dont have a lip.

[@charlesdecelles9798]

Okok im asking cause on mine (superjet 650) the stock dome have a lip so im wondering if im better to do it after planning the head. If not i just do the angle to have an outside diameter equal to the inside diameter of the cylimder?

[@charlesdecelles9798]

Btw thanks for your quick reply it's realy appreciate

[@brandonjonathantoddsnowden2908]

About how much would this cost if I was to pay someone to do it

[@EricksonMachinePerformance]

I charge $75 -100 for twin heads. $125-150 for triples

[@founddeadrepairz6433]

Can you mill a yz400 4 stroke head

[@EricksonMachinePerformance]

Yes. No problem. We also do valve jobs

[@marcusmadrid7508]

Why didn’t you program the mill? That Haas can do so so much more

[@EricksonMachinePerformance]

I cnc machine cases weeky for 5mm, 6mm , 8mm, 10mm and 12mm cranks ect. Our Cnc mills and lathes are always running. Taking a quick cut would be a waste of time to write a program. I can do it manually WAY faster.

[@bikersoncall]

Right off the bat, you could explain what the 'squish' is. An explanation of the formula you use or rule of thumb for how much you are taking off would 100 time more useful than how to run the machine..

[@EricksonMachinePerformance]

Squish is the distance from the crown of the piston to the crown of the dome. I have a video on it

[@EricksonMachinePerformance]

Your looking for an exact number that there isn't. Depending on the engine, fuel, ignition timing, compression, bore and stroke ect. This video is to teach you how to machine this style head. Understanding it would be a much more in depth video. On a yamaha 701 for example Depending on ur setup and fuel you could run as loose as .075" to as tight as .03. Running to tight can cause issues and running to loose you loose power.

[@koro287]

That poor impact driver, all that swarf falling into the armature vents.

[@EricksonMachinePerformance]

Still using the same m12 driver 3 years later without issue. And it was fairly well used in this video. Machine shops are a harsh environment. Milwaukee FTW!!

[@Braapcity]

I am surprised you still have fingers!

[@EricksonMachinePerformance]

Nothing I did was unsafe. I have been working as a machinist for 25 years at this point and have worked on lathes and mills at least 40-60hrs a week since I started.

[@Braapcity]

@@EricksonMachinePerformance Hey I didn't say you were unsafe and I get it you been doing it for years that's cool. I know machinists as well and when they come to my shop and watch me put my fingers close to a rotating brake rotor I get the same comment - "You'll only do that once after your fingers get caught". That being said, I am surprised you still have fingers be it as it may that you are a good machinist, that is outside of my statement I didn't say you weren't or unsafe. I just said hey, you got fingers?!

[@EricksonMachinePerformance]

@Braap City Please understand I didn't take any offense to the comment. There are safe ways to act around a lathe and unsafe ways 100%. Manual lathes and mills are dangerous pieces of equipment. I see how it could look scary but it really isn't if your careful and dont risk your digits. It all depends on the way to hold the sand paper ect.. I have never been hurt running wetal cutting equipment. That being said working as a mechanic I have gotten stitches and broken fingers over the years

[@EricksonMachinePerformance]

And yes I still have all my fingers.

[@Braapcity]

@@EricksonMachinePerformancehow much would it cost me to send 3 Arctic Cat ZRT 600 heads to you for work? I am interested in more snap with my Braap