Fuel pump modification clarity needed

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just4kicks
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Fuel pump modification clarity needed

Post by just4kicks » Tue Mar 20, 2018 2:12 pm

Hi all,

So I have an NC23 with the dreaded ebay fuel pump. The diode on the pump blew and I got a replacement diode which I'll be installing soon. I have found a possible fallback solution but need to know the following 1st.

The pump uses a points system to activate the pump. It also has accommodation for a vacuum pipe at the top to actuate the pump incase of power loss. On my CBR400 NC23, I want to know if I can add an adaptor to replace the blanking screw normally used for syncing the carbs and attach a vacuum pipe from there to the fuel pump? Would this affect my carb sync at all?

pptom
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Re: Fuel pump modification clarity needed

Post by pptom » Tue Mar 20, 2018 5:44 pm

I can't give you a definitive answer, only to say that I have a couple of bikes which use the inlet vacuum take off to solely power the fuel pump which you have to remove to balance the carbs. They are getting on for 400cc per cylinder though.
On those I know the vacuum to the pump is a closed circuit so it doesn't rob or add much air to the cylinder. Only the amount which the pump diaphragm moves

dunkenb
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Re: Fuel pump modification clarity needed

Post by dunkenb » Fri Mar 30, 2018 6:47 pm

You could do away with a points type fuel pump and fit a Facet style solid state pump ?

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JZH
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Re: Fuel pump modification clarity needed

Post by JZH » Sat Mar 31, 2018 9:49 am

If this is a "standard" Honda Mitsubishi fuel pump, there's an optical points kit out there you can retrofit. I've got one on my RC36's fuel pump right now. A Dutch guy on ADVRider makes them for KTMs, which apparently also use the same pump...

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just4kicks
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Re: Fuel pump modification clarity needed

Post by just4kicks » Mon Jun 11, 2018 8:59 pm

Hi guys, sorry for the late reply, so I've manged to replace the diode with a higher rated diode and since its been running sweet. I have a spare pump now which I also replaced a doide on which I keep in the boot for just in case. Can u send a link for these optical points as my buddy with an nc29 has the same issue pls?

dunkenb
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Re: Fuel pump modification clarity needed

Post by dunkenb » Sat Jun 16, 2018 12:22 pm



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