got the fcr installed

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Gen1Pat

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Got this bad boy from 00' WO YA!. Stayed late at work yesterday and got it installed. Has all the factory YFZ jetting, 42 pilot, 155 main, and the idle circut seems nearly spot on. No surging at WOT, but will have more jets come Thursday to dial it in completely. Midrange has a lean bog, but didn't have the time during work to adjust the needle.


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Super tight fit!


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Need the rappy intake, and need to heat it up, had to use hose clamps.


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Stock YFZ cable fits Warrior housing without modding!
 
Bout time!! I was tired of knowing its setting on a shelf! If you want a better air box, hit me up, ill give you the same deal I was gonna give James. Cant wait to hear feed back on that carb!
 
Lol, thanks weston. Bout time someone replied about this install. Thing is a monster. Had to shim out the rear fuel tank mounts cause it hit the carb some. Made me glad that the cable not only fit the stock housing, but I have full travel of the slide without modding it.
 
I can tell that just revving it in the shop, it seems to rev out much easier. Feels flightier, like a newer quad. The thumb throttle isn't as stiff either.
 
Can't remember... Hopefully I will get to tune the midrange today. With the midrange being lean I don't think that it whistles yet.
 
what size FCR do you have? I have a 39mm im trying to get to fit on mine and the air box is a pain to get to fit right
 
39mm off a YFZ. I got it from a fellow member on here. Had to use the Raptor 350 intake, have to heat it and shove the carb in. The intake tube coming from the air box is a tight fit, but I was able to stretch it over the carb's inlet. It is easiest to install the rappy intake, then the carb, and secure it with clamp. Then, take the clamp off the air box side of the intake tube, and shove it on the carb and clamp it. Then retighten the factory clamp you loosened.
 
Ran into a little snag trying to tune it in today. I can't get the midrange dialed in because the factory jet needle only has 1 freakin notch in it! I managed to get it somewhat decent so I could satisfy my craving and ride her around our shop. Used 2 small o-rings to raise it and installed a 165 main. Still far from right but good enough to play putt putt. Had to order a jet kit to 55 bucks. Genuine Keihin kit with mains up to 175, pilots up to 52, and the NCVQ jet needle which is thinner than the BBW that's in it, and it has 7 notches to play with. Will have that Tuesday(ish). No riding the wardog for me this weekend, looks like the ole fourtrax gets to run.
 
I know how you feel about not being able to ride man.. I'm have'n jetting issues with the 490.
We bump started it today, and I took it for a tour down the alley.. It's ok on the bottom end, but falls right off up top (Way lean). I think I'm about to venture into a jetting nightmare.
I've been thinking about buy'n a new Keihin PWK 40mm, I heard their way easier to tune?
Plus I still need to reweld my kicker shaft, and put that back together..

So I'm gonna go play with the Scrambler this weekend, and see what I can break on it.. lmao
 
Maybe not. If the idle is good then you know it is midrange and possibly main jet related. But... newer carbs are much better than that golden oldie you have there.
 
I have never run a Keihin carb before...
Are they pretty good or what?
I've heard lots about them, but not much feedback. Like what's the FCR all about?
Is it a round slide, a flat slide, or a butterfly? Is it in anyway similar to a PWK?

I just ask cause a new PWK is around $250 bucks, and I would like to know more about the brand..
 
I've always had good luck with keihins. Most mfgs use em if I'm not mistaken. I'm not too familar with the different series of carbs they have, PWK, PE, etc... The FCR is a flat slide. Very nice carb imo, and from what I've heard others agree. Seems to be that most people use them now for modded bikes. The needles are super easy to change, all you need to do is remove the 2 allen screws that hold the top cover on, then remove the 1 allen screw that holds the needle in. Pull out the needle and swap it out, or change the clips postion. That easy, no need to take it out of the bike. It also has a 17mm cap on the bottom of the bowl to access the main jet (7mm hex), and you can get to the pilot from there with a mini screw driver. There are several accel pump covers for it that hold extra fuel, eliminate hot start issues, tunable leak jet maximizes volume of fuel and duration of squirt. You can install a long fuel mixture screw that you can twist with your fingers. Worst part is most yfzs did not have adjustable needles (like mine) and you have to buy one. From what I've been reading the yz dirtbikes have adjustable needles. Seems to be that these carbs are very tunable for your riding needs and engine set up. Reminds me of a Q-JET, you can really taylor the fuel curve.
 
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Reminds me of a Q-JET, you can really taylor the fuel curve.
Gawd that brings back some memories..
Not very good memories either.. lmao

But I think I'm gonna go with the PWK, or the PWM.. I was also looking at the PJ flat slides to, cause their cheaper.. But 38mm is the biggest you can get in a PJ. 39mm with the PWK, and 40mm with the PWM.

I did some homework on the FCR, and found it could be used on a 2 stroke but was designed for 4 strokes. It's just like my neighbors warrior though. He's got a Keihin 36mm PE on his, and it runs pretty damn good. That carb was designed for 2 strokes. lol (but the PE's look cheap)
I think I would be better off sticking with the PW series though?? If not for the tuneability, for the performance.

Anything is better than this crappy old mik-coo-knee VM. :tdown:
 
Watch the smack on the mukuni... I run a 38mm rs mukuni on mine, its crisp and is uber easy to tune, and it just pulls like a mofo!
 
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