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Discussion Starter #1
I have the 170 4v koso unit and a pretty large diameter exhaust, chimera, 34mm tb, etc.... The pcv/wb2 was working great and was running an 8 hole injector for a while, did ok but the trims in 4th up around 8-9k was getting in the 70's range (76-75). I felt this was a bit much and ordered a 10 hole from HR over a month ago, installed it last night. Luckily, I have a spare ecm so I swapped out the one I had dialed in with the 8 hole, put in the spare one, reset it, and made a bare map on the pcv. Took about 45 mins of running/riding and applying trims to get it good. afr's in line and the motor actually running a bit cooler which is good. I think the injector was just having a hard time keeping up. Trims now in the 40 ish range where before it was n the 70's

last step before a carb is installed. :)

just figured this may help somebody.
 

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I have the 170 4v koso unit and a pretty large diameter exhaust, chimera, 34mm tb, etc.... The pcv/wb2 was working great and was running an 8 hole injector for a while, did ok but the trims in 4th up around 8-9k was getting in the 70's range (76-75). I felt this was a bit much and ordered a 10 hole from HR over a month ago, installed it last night. Luckily, I have a spare ecm so I swapped out the one I had dialed in with the 8 hole, put in the spare one, reset it, and made a bare map on the pcv. Took about 45 mins of running/riding and applying trims to get it good. afr's in line and the motor actually running a bit cooler which is good. I think the injector was just having a hard time keeping up. Trims now in the 40 ish range where before it was n the 70's

last step before a carb is installed. :)

just figured this may help somebody.
I'd love to test that 8 hole if you decide to part with it. I have a finbro 6 and finbro 10 and need something in the middle.
 

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Thanks for sharing your information.

Right now I'm using a Finbro 6 hole type B injector and I see trims between -20 and -6 thru out the RPM range.

I used a yuminashi 8 hole F/I and I had a hard time to get it to work, not sure if I was using a stock throttle body or my Koso 34mm throttle body. I might do a retest using the 8 hole on both of my groms.

Right now I'm still trying to figure out the crank case pressure fix.
 

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Discussion Starter #4
the yuminashi one was a nightmare, I had one. always dumped wayyyy too much fuel. I think it was a knockoff. that's why I had the 6, then the 8. now the 10 is doing well. it took a while just to get it to idle though, as is common. what I did was crank the throttle stop screw in a few turns, got the afr right, then turned it about a half a turn down about every minute or so, so it could learn. idling good at 1600 now. rode bike into work this am, cold start and idle was good. No stalling,etc.:)
 

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Yeah franco stated that the 10 hole injectors were popular for 170 4v setups.

Tempted to try the 8 hole injector on my 164cc but its probably too big, The 6 hole type b injector has been working very well, plug has some color but i would like to see it a little darker. I did just install a forza fuel line between the pump and injector and it seems to of made a difference at higher throttle openings, though it could be a placebo.
 

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Discussion Starter #6 (Edited)
it is. lol. I tried it as well. zero trim differences from stock line to larger line. its a myth. if it truly was a restriction, with the new line the trims would have dropped some.

use the 8 hole,. I had it in the 164 as well. worked great.
 

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it is. lol. I tried it as well. zero trim differences from stock line to larger line. its a myth. if it truly was a restriction, with the new line the trims would have dropped some.

use the 8 hole,. I had it in the 164 as well. worked great.

you going to letting yours go? *wink wink nudge nudge*
 

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all depends on your setup. stock ecu, stock rev limit, stock TB and head, the pcx injector will likely flow PLENTY.
Uh, OK.

PCV/WB2, +500 to rev limiter, Finbro TB and big valve head. So, none of the things you mentioned.
 

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Discussion Starter #16
I DONT HAVE THPART NUMBER OFF HAND, like said ordered from HR and that was it. prior one was the 8 hole I got off amazon.
 

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I would suggest the Finbro 6 hole. Once you go 170cc or more, it's just better suited, you fuel corrections won't be as extreme.
Thank you. Is the Finbro 6 hole (type b?) injector different than the PCX150 injector?

This injector business is confusing.
 
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