2018 yz125 jetting help

yamaharider471
Jetting seems to be really good right off of the showroom floor. Added a FMF factory fatty and powercore silencer and it still runs great. MXA recommended to go up to the 440 main jet from the 430 that comes stock.

My next investment is going to be the vforce reed cage setup. This would make sense to go up a size in the main jet correct? More air would mean needing more fuel. Just hoping i have this correct.

Any advice appreciated, thanks

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BR8ES
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BR8ES 11/12/2018 10:48am
11/12/2018 10:48am
Save your money and run the stock reeds.


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Falcon
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Falcon 11/13/2018 3:27pm
11/13/2018 3:27pm
BR8ES wrote:
Save your money and run the stock reeds.


Paw Paw 271 wrote:
X2

Paw Paw
I disagree. I found the VForce 2 to be a welcome addition to my '01YZ125, and I also had one on the '15 I owned. As far as I know the '18 is fundamentally the same top end.

OP, you won't get any more power, but the initial throttle response and snap was noticeably better for me, anyway.
You will not need a bigger main jet nor needle adjustment, but you may need a bigger pilot or at least go out with your air screw.

If you are looking for more power, however, then I'd suggest going another route initially. The bikes I had reeds on were ported and had head mods. I added the reeds later and was happy.
BR8ES
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BR8ES 11/13/2018 4:25pm
11/13/2018 4:25pm
BR8ES wrote:
Save your money and run the stock reeds.


Paw Paw 271 wrote:
X2

Paw Paw
Falcon wrote:
I disagree. I found the VForce 2 to be a welcome addition to my '01YZ125, and I also had one on the '15 I owned. As...
I disagree. I found the VForce 2 to be a welcome addition to my '01YZ125, and I also had one on the '15 I owned. As far as I know the '18 is fundamentally the same top end.

OP, you won't get any more power, but the initial throttle response and snap was noticeably better for me, anyway.
You will not need a bigger main jet nor needle adjustment, but you may need a bigger pilot or at least go out with your air screw.

If you are looking for more power, however, then I'd suggest going another route initially. The bikes I had reeds on were ported and had head mods. I added the reeds later and was happy.
Glad you were happy Falcon, I have never really noticed squat with VF reeds. I would spend that money on a good rear knobby, maybe a top end or rings or just riding fees. Maybe they would compliment other stuff, but as a stand alone... meh.

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pdub187
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pdub187 11/13/2018 11:03pm
11/13/2018 11:03pm
I felt like I got snappier throttle response on my yz125 when I fitted a set of vforce reeds.
yamaharider471 11/16/2018 6:45am
11/16/2018 6:45am
BR8ES wrote:
Save your money and run the stock reeds.


Any knowledge on the lectron carb for this bike? Is a true plug and play item or is there some tinkering that needs to be done once its installed?
BR8ES
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BR8ES 11/16/2018 4:11pm
11/16/2018 4:11pm Edited Date/Time 11/16/2018 4:13pm
Telling ya, if you must experiment... go Smart Carb or Keihin(STIC is a nice add on too).

BR8ES
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BR8ES 11/16/2018 4:12pm
11/16/2018 4:12pm
yamaharider471 wrote:
Any knowledge on the lectron carb for this bike? Is a true plug and play item or is there some tinkering that needs to be done...
Any knowledge on the lectron carb for this bike? Is a true plug and play item or is there some tinkering that needs to be done once its installed?
More than likely there will be tuning... some have had great luck and others keep chasing their tail
yamaharider471 11/17/2018 2:07pm
11/17/2018 2:07pm
BR8ES wrote:
Telling ya, if you must experiment... go Smart Carb or Keihin(STIC is a nice add on too).

Where do I find this smart carb?
BR8ES
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BR8ES 11/17/2018 2:32pm
11/17/2018 2:32pm
BR8ES wrote:
Telling ya, if you must experiment... go Smart Carb or Keihin(STIC is a nice add on too).

yamaharider471 wrote:
Where do I find this smart carb?
Technology Elevated.... FB or website.
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USA 3/1/2019 5:56pm
3/1/2019 5:56pm
yamaharider471 wrote:
Jetting seems to be really good right off of the showroom floor. Added a FMF factory fatty and powercore silencer and it still runs great. MXA...
Jetting seems to be really good right off of the showroom floor. Added a FMF factory fatty and powercore silencer and it still runs great. MXA recommended to go up to the 440 main jet from the 430 that comes stock.

My next investment is going to be the vforce reed cage setup. This would make sense to go up a size in the main jet correct? More air would mean needing more fuel. Just hoping i have this correct.

Any advice appreciated, thanks

What did you end up doing? I'm curious to see how you liked the mod(s).

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