For those FCR carb owners!!!

[Giz400ex]

I'm not really up to date on this carb so I was wondering for you owners if you help me out a bit. They say the FCR will give you more hp and better throttle response. Well, right now I have the Lrd ehaust with the KN filter and jetted. Unless this thing is amazing, I already have good throttle response (I think so)!!! What I'm really saying is it really worth the 425.00 and why???????

[nakomis0]

I always knew carbs where good, But I didn't really understand how much they would help till I raced a guy that had one. I had all the mods that you see in my signature except a carb. The other guy had a 426 kit, 10:1 piston , drop-in cam, full exhaust, no porting and no valve work. When we raced it was equal at the start, then I would pull on him in the mid-range, and then at top end he would start gaining, and we would ussually end up right next to eachother at the end of the track. He had a Lectron. I was really impressed.

(FCR) As far as throttle response , it is a little more responsive. Thats probably because the carb has some kind of pump for the fuel. If you have the carb off and push the throttle, it shoots a straight line of gas about 3 feet, like a squirt gun. its pretty cool:blah

[NVR2L8]

I've heard that stock motors with exhaust and intake mods benefit slightly from the 39mm FCR, but in my opinion, the increased performance isn't worth the 400+ bucks most places are asking for the carb. When it comes to modded engines though...416cc and up...the carb really shines in its ability to help these motors develop better throttle response and overall power. Still though, there aren't any dyno charts floating around to prove or disclaim these claims...just seat of the pants testing from those who have one, both on a stock and modified engine.

For what it's worth, I have an FCR installed on my newly upgraded motor (416cc & XR400cam), and wouldn't go back to the stock carb for any reason. My new motor starts easier, runs better when cold, and has much more throttle response than when the machine was stock. Now if my machine were still stock with similar mods such as yours, I think I would stick with the stock carb and use the money for other mods, such as a better suspension. BTW, in my opinion the stock carb is very good and very easy to work on...for those reasons my leftover 400EX carb is going on my wife's 300EX, if/when I can ever remember to order a 350X intake tube. *L*

[xcntry]

NVR2L8, Is that a stock xr 400 cam you have . How do you like it? Thinking about getting one myself.

[oynot400]

NVR2L8,
Are you saying that an aftermarket carb will fix the cold starting problem? If that is true then that is my next mod. I will spend $400 to have my ex start in the winter.

Giz400ex, where are you finding a FCR carb for $425? The cheapest I have seen is $450.

[kabd69667]

If your buying a carb, you can't go wrong w/ a fcr. They are 2 hp over all other leading carbs.

[NVR2L8]

Yep, I have a stock Honda XR400 cam. I went with it because it's a drop-in that doesn't require hardfaced rockers. It's also not a real agressive cam, but it helps develop a little more power in the mid to top end without sacrificing bottom end power. I'd have to say it compares to a lot of the "all-around" cams offered by the other aftermarket companies. It's great cam and I like it so far, but part of me feels that if I had to do it again though, I would have gone with XR's Only's HRC copy cam, which is also a drop-in cam but is a little more aggressive. Of course, when saying that I'm referring to the mod's I've done to my motor, and concerning the type of riding that I do...a mix of trail and dune riding.

I don't know if an FCR carb will eliminate cold starting problems on a stock motor...don't have any experience with a stock machine equipped with that carb to make a comment based on fact. Know what I mean? But my new modded engine starts right up with just a few pumps of the throttle, and idles without having to constantly sit there and manipulate the throttle. To be honest, in my opinion most of the cold starting problems with a stock machine and stock carb are attributed to the engine running really lean on the pilot and fuel screw adjustment. More often than not, going up to a 42-45 and adjusting the fuel screw usually eliminates most of the problem, and also provides a little better low end response.

Also, like I said before, I think the stock carb is actually a really good carb and flows well enough for a stock motor, it just needs to be properly jetted--it also has an accelerator pump like the FCR. Perhaps someone like Gabe can comment on whether or not the accelerator pump can be adjusted to provide a little better low end response.

[papaw]

oynot400,
before you go buying a new carb for cold starts first try richening up the pilot/slow jet a couple of steps,might save you some dough!!!!!!

[oynot400]

papaw,
I tried that last winter, with no luck. Then I installed the 440 kit and jetted it, again no luck. Don't know what to do I was hoping that someone with an aftermarket card would know. I plan on getting a carb this fall any way. So if someone does know please let me know. Thanks

Yeah a jet kit fixed all my starting problems..