Is the fuel pump needed?

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SeattleZXR
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Joined: Wed Jun 24, 2015 2:38 pm
My Bike: Kawasaki ZXR400

Is the fuel pump needed?

Post by SeattleZXR »

I have a 1993 L model. I'm curious, since it's carbureted and not fuel injected does it really need the fuel pump? I have a lot of bikes with a lot larger displacement that work just fine without a fuel pump.
dave111
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Joined: Thu Oct 01, 2015 11:48 pm

Re: Is the fuel pump needed?

Post by dave111 »

An interesting question, one i'd pondered on as well, its, not like the carbs feed inlet is much lower than the lowest part of the petrol tap, try it and see then let us all know?
SeattleZXR
Posts: 33
Joined: Wed Jun 24, 2015 2:38 pm
My Bike: Kawasaki ZXR400

Re: Is the fuel pump needed?

Post by SeattleZXR »

I am taking mine to a dyno at some point so I'm gonna ask the experts there what they think
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Dominik
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My Bike: Zxr 400 L3
Location: Trier - Germany

Re: Is the fuel pump needed?

Post by Dominik »

Works 90% but does not run properly on full throttle at high rpm. If you want to lose weight or electronic install a vacuum fuel pump from mikuni or dellorto. they work fine on the zxr ;)
Zxr 400 SL - 130kg
SeattleZXR
Posts: 33
Joined: Wed Jun 24, 2015 2:38 pm
My Bike: Kawasaki ZXR400

Re: Is the fuel pump needed?

Post by SeattleZXR »

Do you have a part number for the vacuum pump that work with the bike?
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Dominik
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Re: Is the fuel pump needed?

Post by Dominik »

Mikuni DF44-18
http://www.bsmkartsport.de/de/Benzinver ... klein.html
DellOrto P32
http://www.kartshop-birel.de/DellOrto-B ... e-P34-PB-2
I have the dellorto one installed and it´s in my opinion the better one but both will work fine. In Germany they´re available, don´t know if you can get them easily in UK.

Edit: They come with 6mm fittings instead of 8mm which the zxr has so you will need an adapter/ converter, too.
Zxr 400 SL - 130kg
SeattleZXR
Posts: 33
Joined: Wed Jun 24, 2015 2:38 pm
My Bike: Kawasaki ZXR400

Re: Is the fuel pump needed?

Post by SeattleZXR »

Thanks for the links. I'm in the US so that makes things even harder to get but with the a part number I can usually find something over.
SeattleZXR
Posts: 33
Joined: Wed Jun 24, 2015 2:38 pm
My Bike: Kawasaki ZXR400

Re: Is the fuel pump needed?

Post by SeattleZXR »

This looks like the correct unit but it doesn't refer to it as a P34

Does it look like the right one to you?
http://sharkshifter.com/zc/index.php?ma ... ts_id=1388
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Dominik
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Re: Is the fuel pump needed?

Post by Dominik »

Yes that´s it exactly, 55L/h!
Zxr 400 SL - 130kg
SeattleZXR
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Joined: Wed Jun 24, 2015 2:38 pm
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Re: Is the fuel pump needed?

Post by SeattleZXR »

Does it hook up to the air box? I'm a bit confused about how to install it.
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Dominik
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Re: Is the fuel pump needed?

Post by Dominik »

It has two holes for as fitting option but it´s light enough to hold its own at the carb.
Here you see how I fitted it:

Image
http://www.pic-upload.de/view-28499896/ ... 5.jpg.html

Image
http://www.pic-upload.de/view-28499897/ ... 6.jpg.html

Image
http://www.pic-upload.de/view-28499894/ ... 7.jpg.html
Zxr 400 SL - 130kg
SeattleZXR
Posts: 33
Joined: Wed Jun 24, 2015 2:38 pm
My Bike: Kawasaki ZXR400

Re: Is the fuel pump needed?

Post by SeattleZXR »

I'm sorry if my question wasn't clear.

I know:
1.one port is an inlet
2.one port is an outlet
3.where does the 3rd port hook up too?
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Dominik
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My Bike: Zxr 400 L3
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Re: Is the fuel pump needed?

Post by Dominik »

Well as it is a vacuum pump it needs a vacuum^^ that's the third one. Put a Y-piece in the hoses below the rubbers and connect them to the pump. You can (almost) see it in the pictures ;)
Zxr 400 SL - 130kg
SeattleZXR
Posts: 33
Joined: Wed Jun 24, 2015 2:38 pm
My Bike: Kawasaki ZXR400

Re: Is the fuel pump needed?

Post by SeattleZXR »

I think I understand where to hook them up now. Same ports that are used to sync the carbs?
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Dominik
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My Bike: Zxr 400 L3
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Re: Is the fuel pump needed?

Post by Dominik »

exactly
Zxr 400 SL - 130kg
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