Read through the archived posts about Edelbrock's new QwikSilver carb for the 400EX, but didn't see posts from anyone who's actually running one. Has anyone bought one of these, and if so, what is your impression?

 

I have one on order through Golden West Cycle. The cost is $399 and that includes the throttle cable. I am expecting it either next week or the week after. Once I get it installed, I will certainly be posting with the results. I have a GPS on my bike which can measure my peak speed, so I will be able to inform everyone if the top speed increase claims are valid.

 

Give us info on throttle respone from low to top as well as how it sets up.Been waiting for some input on this carb compared to FCR.

 

Can you run the thumb throttle with this carb? I am also more interested in overall throttle response & power than a top speed improvement. Personally I think $500 is TOO much for an FCR.

 

On the Edelbrock web site, they list both an application for both a twist and thumb throttle set up. I'm looking at overall response as well, and also wonder what the bore size is on the QS carb compared to the stock or FCR carb...

 

First, it is available for a twist or the thumb throttle. It comes with the appropriate cable either way.

I asked about bore size because 3 & 4 Wheel ATV Action magazine listed the units on the Duncan Racing 400's as 39mm. The guy at Edelbrock tells me it is an OVAL, not a round bore. He says it measures 30x34 (I believe) which he says equates to a 36mm round bore. I know that bore size is not everything, but that the venturi design can result in better flow. I guess I will just wait and see.

I am pretty sure that my stock carb is causing my modified engine to not breath to its full capability since I am still running the same jetting as when the bike was only piped. I guess I will just have to wait and see.

 

slyder, would like to no if it has a choke on it.
hoping to hear good things about it!!!!!
i'm looking for bottom and mid power, i dont care about top end. i'm a trail rider not a rode rider!

99 426ex,11:1,port job,web cam,rev box,k/n,dyno
jet kit,6 air box vents,ids-2 pipe = power

p.s. raptor owners beware! this little 400 is some thing to worrie about.

 

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Slyder,
What is the top speed on your 440? What was it when it was stock? What tires [size] are you running and what size sprockets do you have? As Gabe said, I don't really care how fast my quad goes [top speed] I care how fast it gets there. But I am curious to hear how the top speed varies between set-ups. Thanks in advance. -RT

 

The top speed on my bike as is is 70mph. This is with 22" Holeshot XCTs and a 14 tooth front sprocket. This has my final gearing the same as with stock gears and 20 inch tires.

I agree that it is a rare occasion to be going 70 mph on my bike. Top speed, however, is an indication of horsepower, and a cheap and easy thing to measure (Dyno runs can get expensive). It takes more power to overcome the wind resistance which builds as you pick up additional speed.

As I have mentioned previously, I think I am choking the engine at wide open throttle since I am still running the same main jet and needle clip position as I was when the bike was only piped with a K&N and Dynojet kit. And no, it wasn't running terribly rich back then, just jetted per Dynojet's instructions. Physics says that if I haven't needed to add more fuel, than I am not pulling additional air. So, hopefully, this is the case, and this Edlebrock carb will give me the flow the engine is looking for. Crossing my fingers.