Pumper carb?

For those who have added a pumper carb (Mikuni or Edelbrock), have you noticed a big difference in power and acceleration? Been looking at a couple of web-sites that offer both brands. Of course they really have favorable reviews of the carbs. they sell, so I'm looking for some opinions of riders who have installed either pumper carb.

'99 XR400 - FMF Powercore IV, UNI, FMF Powerbomb header, other goodies...........

I think what you'll notice most is the way in which the power is delivered under different circumstances. The off idle and low end throttle response in particular is significantly improved and the power curve is a bit broader down low. In respect to the Edelbrock, some other benifits will be easier starting when the bike is dumped, easier tuning for different riding conditions or when adding aftermarket components (pipe, cam, etc), more tolerant to changes in altitude, etc.

A pumper carb is the best mod u can do to ur 400. U will only gain a slight increase in power but it makes the bike much more responsive and alot eaiser to start. If u have problem with boging or hesistation that will be totally eliminated. It will make it feel like a diffrent bike

:cry: I have the Mikuni Pumper!

I love the instant POP once I hit the throttle! :cry:

Yes, I'd buy it all over again! It will do the loop trick in 2nd gear without any tug on the bars! Up the hills you really have to be careful of the throttle, it will hit imeadiatly.

Drawbacks: It will flood once dropped. It will spew fuel on its side. It does have the conventional JETs which need to be adjusted once you gain altitude! It is a carburator and not a majic carpet! :cry:

I have the Edelbrock pumper. As it was explained to me, the Edelbrock pump only works whenyou wick the throttle hard. Under normal acceleration it doesnt squirt. 4 strokes have that little stumble off idle and low end. That and the starting is where pumper carbs really shine. On the trail, I like the seamless power delivery on tight single track also.

has anyone tried them both to compare the power, ease of adjustment, reliability?

I'd like to buy one, but being the price is pretty high, i dont want to be sorry with the one i picked.


Flynall here on TT has bought & tried them both. You can send him a PM for more info.

Thanks for the opinions guys!

Don't forget that the Edelbrock is designed for use with an after-market exhaust. Don't even think about buying one and not at least having your stocker opened up.

My freind put a Kiehin FCR pumper carb onto his XR400 and claimed that it raised power all over the powerband. However, the cost is a MUCH more than either the Mikuni or Edlebrock.

For a Mikuni, I would go with XR's Only.

For the Edlebrock, Barnums.

Each has sold a lot of the respective carbs.

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