I’m watching you ride with my phone turn sideways steering it back-and-forth and lifting up as you go over the jumps lol And holding the Hangtime while wincing when it looks like you might case it so while Dallas and the 49ers along with American fandom figure out what they’re gonna do on the next down, I am vicariously living my life through your video
A tighter squish pushing more of the charge into the dome area where it can be used for power production. It also helps stir up the charger before the spark fires it off for a more complete burn.
Thanks man! A subscriber is mailing me a GYTR ignition for the 125 to try out and even keep. I'm really excited to try that out! He says it should complete my package
That’s awesome. I’ll be interested to see how you like it. I’m right now watching your video on the rad valve compared to V force and stock. I have an 09 YZ 250. And watching your videos I realized I don’t really know how many hours are on my V force 3 I guess I’m gonna order some petals .
@@jspreparednessandself-reli4856 yeah I'm going to do a review on that CDI. I plan to break out a timing light and check to see what they did differently too. Oh yeah if you don't know the hours on the reeds I would surely snag up some replacements for about 55 bucks and freshen her up. It usually will reward you with increased top end power when you swap the old ones out with new ones
Or i guess another question I have, is it recommended to machine the head after port and polish of the cylinder? Or can you leave the head stock. What kind of difference will it make
I would say the head mod is the biggest bang for the buck and no modified bike is truly modified till the head is done. Cylinder porting performance gains are small compared to what the head can do. Honestly alot of bike these days don't even need porting but most can use a good head profile, set for the fuel you plan to use. Usually all I do is polish the exhaust port on the cylinder and call it good. That will give you 80% or more of the gains of a fully ported cylinder on these modern bikes. Best part is it can be done quickly and easily. Which is good because cylinders don't last forever and if you trash a cylinder that has a 300 dollar port job you may be more butt hurt then if you trash a cylinder that has only a polished exhaust port that you was able to do yourself at home in about 30 minutes. So I suggest the head mod first, probably first over any other mod. Then build on top of that.
@@UpAllNight91 okay, hmm, my brothers cylinder for his yz 125 was just port and polished, I’m a machinist so I was going to machine the head, my grandpa suggested I face .020” off the head, then cut down so there’s only .010” gap from the very edge down to where the taper starts where the top of the piston would match up to, right now it’s a .020” gap. But would I have to cut out the dome as well, or wouldn’t I leave it? Brother wants a little more top end power, he’s not concerned about bottom end, and just wants to run premium pump gas
@@connorbarnstable9148 0.020" is a very tight squish sure going to need race fuel with it that tight. I like to keep them closer to 0.030" for a safe margin. But 0.020" should make for a very sharp throttle response. For more top end you will surely need to open the dome back up. You will want to open the dome up to get the over all CC's or compression ratio closer to stock. Because having a higher compression ratio will surely rob top end power. I currently run just a small hair over stock compression. Its enough to bring in some bark but not rob top end powrr
You seem extremely knowledgeable about these bikes.. quick question.would it be acceptable to run a BR9EIX instead of of a 8 heat range plug? I have a 22’ 125 x that i’m trying to squeeze some more power out of..As you may know they are slightly different with the cdi and timing I believe? Any feedback is appreciated man.
Hello, thanks. I don't know to much about the x models. Does the 125x come with a 8 stock? If it did I would think about using a 9 if I'm going to run her hard. It won't provide more power but will help the motor survive under hard use. I have found the BR10ECMIX, BR9ECMIX and the BR8ECMIX plugs do seem to make more power up top if thats what your looking for
It does come with an BR8 stock. I’m getting rid of the restrictive stock silencerfor a pro circuit 304,I have a vforce 4, jd needle (blue). Which helped significantly. Thank you for you’re input I will run a 9 heat range plug👍🏻👍🏻
@@jewintheoven9442 your welcome. Is the jet kit just jets and a needle or does it include other things? I know on some of the carbed 4 strokes the jetting kits come with stuff that improves the accelerator pump and such
It includes some main jets I think 2 pilots and 2 needles but you buy the kit mainly for the needles because they are only available if you buy the kit.. check it out you will not be disappointed. The blue needle does not taper so thin like the stock needle does from zero to quarter throttle. Appreciate you’re feedback. I have been subscribed by the way!
have you concidered leaning out the MJ (and/or needle) with the higher compression head ,to try and chase some more/ easier overrev as with your prefered head?
Hello. I did consider it but I felt like it was already on the leaner side (as thats where this bike runs best) and if I ran it any leaner especially with a higher compression head it would burn hotter. It would be good for tracks with more on and off throttle like SX but because I used this bike on faster and sandier tracks often I try to keep it overall tuned in a area where it can handle sustained full throttle lap after lap.
How much do you have to machine out of the dome after machining the head? Do you gotta take out the same amount out of the dome as you do from the flat part of the head?
yo my brother nice video!, i asking you some time ago for suspension settings, I would like to know why my 250 is very nervous and how to calm her down?, I mean, it takes my hands off the gas, I have vforce 3 and the whole fmf exhaust system gear ratio 14 50 what do you think I could change? stock exhaust?
@@keithalexander36 i mean my suspension is good.but my engine is very aggresive i cant riding smooth, on my friend sx 250 2stroke riding is very very smooth on my yz is very crisp
@@kubamx2676 what year and what head is on your YZ. A head like the apex XC dome would calm down the hit and response but leave you with the torque and revs
@@kubamx2676 what year? Or better yet what head? The 5UP head from 2003 to 2010 has a ton of snap and hit. The 5WM head of the 2011 to current is lower compression and less hit
Ive got a question for you. One of the bearings that is behind the rotor on my 93 YZ 125 somehow worked its way out of its spot is that possibly the result of overtightening the road or once I was done timing it? After I had put everything back together and was running it, it sounded slightly Rattalee. I was concerned, but I noticed it was leaking oil out of from behind the rotor so I stopped it and then went and checked, and the bearing it come forth not all the way, but enough to let oil through. I’m trying to figure out how that would happen.
@@SethMacgillivaryIm gathering too tight can cause its much like advancing you ignition timing too far can. A tighter squish makes more turbulence which makes for a faster burn in the combustion chamber.
Ridiculous that your videos dont get more attention, so much good information in every video
Thanks! This was one of my earlier videos of my own bike. These videos are little gems to me. Thanks for watching it!
Ur right I love his videos he really smart dude know his stuff I like how he testing this stuff for us to learn off of
I’m watching you ride with my phone turn sideways steering it back-and-forth and lifting up as you go over the jumps lol And holding the Hangtime while wincing when it looks like you might case it
so while Dallas and the 49ers along with American fandom figure out what they’re gonna do on the next down, I am vicariously living my life through your video
😆 lol!
You can hear the differences to awesome video great work
Thanks!
What does the squish band affect what does a smaller one do?
A tighter squish pushing more of the charge into the dome area where it can be used for power production. It also helps stir up the charger before the spark fires it off for a more complete burn.
Another great video. Thanks for the info. The 125 sounds great!
Thanks man! A subscriber is mailing me a GYTR ignition for the 125 to try out and even keep. I'm really excited to try that out! He says it should complete my package
That’s awesome. I’ll be interested to see how you like it. I’m right now watching your video on the rad valve compared to V force and stock. I have an 09 YZ 250. And watching your videos I realized I don’t really know how many hours are on my V force 3 I guess I’m gonna order some petals .
@@jspreparednessandself-reli4856 yeah I'm going to do a review on that CDI. I plan to break out a timing light and check to see what they did differently too. Oh yeah if you don't know the hours on the reeds I would surely snag up some replacements for about 55 bucks and freshen her up. It usually will reward you with increased top end power when you swap the old ones out with new ones
@@UpAllNight91 thanks so much my friend I’ll do that!
I’ll be watching for your video !
@@jspreparednessandself-reli4856 yes sir!
Or i guess another question I have, is it recommended to machine the head after port and polish of the cylinder? Or can you leave the head stock. What kind of difference will it make
I would say the head mod is the biggest bang for the buck and no modified bike is truly modified till the head is done. Cylinder porting performance gains are small compared to what the head can do. Honestly alot of bike these days don't even need porting but most can use a good head profile, set for the fuel you plan to use. Usually all I do is polish the exhaust port on the cylinder and call it good. That will give you 80% or more of the gains of a fully ported cylinder on these modern bikes. Best part is it can be done quickly and easily. Which is good because cylinders don't last forever and if you trash a cylinder that has a 300 dollar port job you may be more butt hurt then if you trash a cylinder that has only a polished exhaust port that you was able to do yourself at home in about 30 minutes. So I suggest the head mod first, probably first over any other mod. Then build on top of that.
@@UpAllNight91 okay, hmm, my brothers cylinder for his yz 125 was just port and polished, I’m a machinist so I was going to machine the head, my grandpa suggested I face .020” off the head, then cut down so there’s only .010” gap from the very edge down to where the taper starts where the top of the piston would match up to, right now it’s a .020” gap. But would I have to cut out the dome as well, or wouldn’t I leave it? Brother wants a little more top end power, he’s not concerned about bottom end, and just wants to run premium pump gas
@@connorbarnstable9148 0.020" is a very tight squish sure going to need race fuel with it that tight. I like to keep them closer to 0.030" for a safe margin. But 0.020" should make for a very sharp throttle response. For more top end you will surely need to open the dome back up. You will want to open the dome up to get the over all CC's or compression ratio closer to stock. Because having a higher compression ratio will surely rob top end power. I currently run just a small hair over stock compression. Its enough to bring in some bark but not rob top end powrr
You seem extremely knowledgeable about these bikes.. quick question.would it be acceptable to run a BR9EIX instead of of a 8 heat range plug? I have a 22’ 125 x that i’m trying to squeeze some more power out of..As you may know they are slightly different with the cdi and timing I believe? Any feedback is appreciated man.
Hello, thanks. I don't know to much about the x models. Does the 125x come with a 8 stock? If it did I would think about using a 9 if I'm going to run her hard. It won't provide more power but will help the motor survive under hard use. I have found the BR10ECMIX, BR9ECMIX and the BR8ECMIX plugs do seem to make more power up top if thats what your looking for
It does come with an BR8 stock. I’m getting rid of the restrictive stock silencerfor a pro circuit 304,I have a vforce 4, jd needle (blue). Which helped significantly. Thank you for you’re input I will run a 9 heat range plug👍🏻👍🏻
One thing I would love to see you review is the JD jetting kit!! It’s about $80 but i’m telling you it made a big difference for me.
@@jewintheoven9442 your welcome. Is the jet kit just jets and a needle or does it include other things? I know on some of the carbed 4 strokes the jetting kits come with stuff that improves the accelerator pump and such
It includes some main jets I think 2 pilots and 2 needles but you buy the kit mainly for the needles because they are only available if you buy the kit.. check it out you will not be disappointed. The blue needle does not taper so thin like the stock needle does from zero to quarter throttle. Appreciate you’re feedback. I have been subscribed by the way!
have you concidered leaning out the MJ (and/or needle) with the higher compression head ,to try and chase some more/ easier overrev as with your prefered head?
Hello. I did consider it but I felt like it was already on the leaner side (as thats where this bike runs best) and if I ran it any leaner especially with a higher compression head it would burn hotter. It would be good for tracks with more on and off throttle like SX but because I used this bike on faster and sandier tracks often I try to keep it overall tuned in a area where it can handle sustained full throttle lap after lap.
How much do you have to machine out of the dome after machining the head? Do you gotta take out the same amount out of the dome as you do from the flat part of the head?
Hello. I honestly don't know the exact amount. I just shave a little and measure and then shave a little until I get what I need.
yo my brother nice video!, i asking you some time ago for suspension settings, I would like to know why my 250 is very nervous and how to calm her down?, I mean, it takes my hands off the gas, I have vforce 3 and the whole fmf exhaust system gear ratio 14 50 what do you think I could change? stock exhaust?
What year? First check is making sure Steering bearings are snug tight. Next I'd turn in some rebound on forks and shock to settle things down.
@@keithalexander36 i mean my suspension is good.but my engine is very aggresive i cant riding smooth, on my friend sx 250 2stroke riding is very very smooth on my yz is very crisp
@@kubamx2676 what year and what head is on your YZ. A head like the apex XC dome would calm down the hit and response but leave you with the torque and revs
@@UpAllNight91 i have stock and the Fresco exhaust and silencer fmf
@@kubamx2676 what year? Or better yet what head? The 5UP head from 2003 to 2010 has a ton of snap and hit. The 5WM head of the 2011 to current is lower compression and less hit
Ive got a question for you. One of the bearings that is behind the rotor on my 93 YZ 125 somehow worked its way out of its spot is that possibly the result of overtightening the road or once I was done timing it? After I had put everything back together and was running it, it sounded slightly Rattalee. I was concerned, but I noticed it was leaking oil out of from behind the rotor so I stopped it and then went and checked, and the bearing it come forth not all the way, but enough to let oil through. I’m trying to figure out how that would happen.
Woh thats strange. That bearing shouldn't have the room to move at all really. Hmm is it the correct crankshaft?
Can to big of a squish cause detonation and how?
you mean too large of a clearance ?
@@UpAllNight91 yes
@@SethMacgillivaryFrom what i gather too wide of a clearance can allow a second flame front to form in the corner of the combustion chamber
@@UpAllNight91 because of all the unburnt fuel, and how does to tight of a squish cause det?
@@SethMacgillivaryIm gathering too tight can cause its much like advancing you ignition timing too far can. A tighter squish makes more turbulence which makes for a faster burn in the combustion chamber.