Injector question

[RustyRodder]

Question regarding injector sizes (Also shoutout to QuantiQualification for his amazing injector video).

I am installing an NK intake, Yuminashi S238 cam, and exhaust onto my bike (also an efie). I purchased a PCX150 injector in anticipation of also doing a 143cc kit, but am holding off on that for now. Will the PCX injector be too much for this setup? or should I just run it, and see if I foul out a plug?

 

[m in sc]

thats pretty much exaclty what im running. shoudl be ok

 

[AZ7000']

thats pretty much exaclty what im running. shoudl be ok

Don't you have the bbk?

 

[m in sc]

I do. the intake and exhaust are going to have the biggest impact though, but truth be told a pcx150 injector will work fine even on a stock motor. been there done it.

 

[RustyRodder]

Thanks- i wish i could find an adjustable cam sprocket, but all sold out from what I can find

 

[m in sc]

ADJUSTABLE CAM TIMING SPROCKET (HEAVY DUTY) (110CC / 125CC ENGINES)

YUMINASHI ADJUSTABLE CAM TIMING SPROCKET (HEAVY DUTY) (CRF110F - MSX/GROM125 - Z125 MONKEY...)

www.yuminashi.eu

?

 

[RustyRodder]

Ordered!

 

[m in sc]

im pretty sure thats where everyone else get them from

 

[RustyRodder]

I saw them at cjr and some places stateside- didnt think to check there. Brain fart.

 

[m in sc]

I meant the us suppliers source them from Yuminashi. (not everyone on here). they were the 1st to carry them way back.

 

[JPMcGraw]

The PCX should be good but i would like to point out that Yuminashi suggests a 155cc injector for the 143 (that they just so happen to sell so 50/50 if that's marketing). I ordered the 155 and 170 and both work well. With my EFI-E set to 250 the mini 3 AFR shows 12.5 under WOT, 13.0 at cruise, and leans out to around 13.3 @ 55mph for the 155. The 170 shows 12.5 at WOT, 13 at cruise, and around 13.0 @ 55mph. The 170 smells gassy at idle so i ran that last summer to ease my worry about another heat failure. Since they are producing basically the same AFR when riding im not sure the 170 runs any cooler other than at idle and possibly 0 throttle deceleration but it makes my brain feel better.

I forgot to add. The 170 creeping around fields low throttle low speed (under 10mph) shows "Rich" (so below its threshold) and the 155 shows 12.2

 

[m in sc]

hell, i ran my old grom with a (genuine honda) pcx150 injector on a 164 for along time, its def fine on a 143 IMHO. mines running a bigger TB, full exhaust, intake, cam, efie, etc. Last time i rode it to work, monday, I was hitting 62-64 mph flatland hauling my RD350 cases to the vapor blaster. I did check my afrs with a wideband with this setup, was fine. (that's in another thread somewhere)

 

[SneakyDingo]

I did check my afrs with a wideband with this setup, was fine. (that's in another thread somewhere)

Probably this, for those who are interested in some reading:

testing the efie with an actual wideband

I found my doebeck narrow to wideband adapter, and figured id give it a test real quick to see where im at on my bike. as expected, its 12.6 or so wot sustained, (a 100% throttle) and between 13 and 13.6 other areas with light cruise tapping 14 on occasion on steady low throttle. the efie is set...

hondatrail125.com

 

[RustyRodder]

hell, i ran my old grom with a (genuine honda) pcx150 injector on a 164 for along time, its def fine on a 143 IMHO. mines running a bigger TB, full exhaust, intake, cam, efie, etc. Last time i rode it to work, monday, I was hitting 62-64 mph flatland hauling my RD350 cases to the vapor blaster. I did check my afrs with a wideband with this setup, was fine. (that's in another thread somewhere)

Your build has been the model for mine so far- I originally planned on a 143, but holding off for now. Those self-soldering connectors are 10x easier than using the iron though! Started getting the NK installed tonight- hoping to take it out with the injector/intake/exhaust tomorrow.

 

[m in sc]

those connectors are fantastic! I'm an old school crimp guy w the actual ratcheting crimper etc, but those are really, really good.

 

[RustyRodder]

those connectors are fantastic! I'm an old school crimp guy w the actual ratcheting crimper etc, but those are really, really good.

I have one of those too, but decided to try them out. Also using weatherpack style connectors to make it all easily reversible.

 

[RustyRodder]

I may need some help here- i installed the intake l, injector, and efie. Efie is at 260mv. But it bogs horridly when i give it throttle, and stalls out sometimes when I let off. Could the 140cc injector be too much with just the air intake?

 

[m in sc]

it takes like 50 miles to adjust the ecm all the way. fire it up, let it idle for like 10-15 minutes cracking the throttle a bit, then do a few light runs.

 

[RustyRodder]

Will do- just out of work, so good timing.

 

[RustyRodder]

Went on my 'learning' loop that ive done before. Lots of flat spots, surging, and no top end (died at 42mph). Swapped the stock injector back for a second loop and it went fine, no surging or flat spots. The chinese knockoff injector may be no good. And i double checked that the efie wires werent reversed.