Best Carb for Instant Throttle Response?

[ill_lil_romey]

Which carb would be best for a fully built 400ex motor, 450 stroker to be exact. Im looking for something that has the best throttle response and good power down low too. I don't know what to get between the 450r carb, fcr 39, 40, 41??

[MIKE400EX]

FCR39

[wilkin250r]

The 39 will give you better throttle response.

[Silverfox@C&DRacing]

yep 39mm FCR

[Chef]

41 with a power now intake.

[MIKE400EX]

Chef, Have you tried the power-now intake? What improvements did you see? Thanks!

[Quadzilla]

Service Honjda CRF450R 40mm FCR works nice. I'm not knocking the 39 or 41mm, they work great, but the 40mm is the newer generation with an accelerator pump that's better suited to 4 stroke singles than the 39mm or 41mm. The squirt duration can be set lower out of the box without mods and the accel pump is less prone to dirt getting into it (the dirt goes down the rod on the 39 and 41 unless you seal them around the boot with Permatex).

The good news is that the older ones can be modded with the Taffy Mod for a shorter squirt duration. I have done this and it works well.

[quadmx7]

39FCR. where can i get some info on that taffy mod?

[400ex2072]

Is the FCR that much better than the Lectron I am running? I have been contemplating getting one for a while after hearing alot of good things about them. When Curtis built my engine he suggested that carb to me but I went with the lectron because it was cheaper and was still supposed to be a great carb. What about those edelbrocks?

[Chef]

Originally posted by MIKE400EX
Chef, Have you tried the power-now intake? What improvements did you see? Thanks!

I went straight from a 39 to a 41 with the Power-Now and I can tell you it gained A TON of HP everywhere, and didnt lose any bottom or throttle response. I would never do it any other way. Now I have 2 FCR41's with Power-Now's and they are both sweet.

[quadmx7]

would it be worth selling my 39fcr for a 41 and gettin the power now intake for my 426ex

[Ryan]

Would a 39fcr be worth it with the normal modifications? example: 416, 10.8:1 piston, Hot cam, ect.....

Any worthy power gain?

[Chef]

I would just put a powernow intake on your 39.

[cals400ex]

Originally posted by Chef
I would just put a powernow intake on your 39.


what is this intake? where can i read up on it?

[TC426EX]

No kidding where can I get info on this "powernow" intake?

[Silverfox@C&DRacing]

I was doing a little searching and found some opinions

http://www.thumpertalk.com/forum/showflat.php/Cat/0/Number/897096/Main/893361

http://www.thumpertalk.com/forum/showflat.php?Cat=0&Board=UBB10&Number=548245&Forum=UBB10&Words=Power+Now---Wow!!&Match=Entire+Phrase&Searchpage=0&Limit=25&Old=allposts&Main=547835&Search=true

keep in mind they are talking about dirtbikes

http://www.exriders.com/vbb/showthread.php?s=&threadid=80450&highlight=powernow

[HondaOnly]

I have heard really good stuff about the FCR's, but i really like my lectron 38mm. The Lectrons offer very quick throttle response and adequate power gains. Also, the lectron carbs use a single metering rod in place of all jets, this offers a very large range of adjustability. One metering rod has the adjustability of more than 10 conventional main jets. The guy i bought my Lectron off had a almost stock 400ex, the carb arrived with the proper metering rod for a stock 400ex, without even purchasing a new metering rod, the carb easily adjusted for my highly modified 440. There are other size lectrons aswell and different types including High velocity lectrons which, i believe, feature a larger taper than the standard 2mm on the non high velocity carbs. The FCR is a great carb, but is it worth close to 500 dollars? Lectons go for roughly half of what the FCR goes for and offers comprable performance. Or, you can pick up a slighlty used Lectron in near perfect condition for around 100 bucks if you look on EBAY.

If money is object and you want the most kick *** quad, the FCR is clearly a better carb from what i have read in comparisons, however, if you want a carb that is easy to tune, makes really good power and wont empty your wallet, i Highly reccomend the lectron carbs. Sorry my input was so late.

[quadmx7]

where can i get a power now? and how easy is it to instal, what does it take?