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Offline rarch

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Re: Vacuum value at idle (rough idle problem).
« Reply #20 on: 05 May, 2016, 10:05:52 PM »
Well done.

I've heard of pumps with internal strainer/filter getting clogged up which reduced the fuel flow, symptoms were lack of high speed but bike could maintain a constant lower speed.

Do you have any idea what would cause a pump to deliver at a higher pressure, could it be a blocked pressure relief valve within the pump?  Maybe it can be cleaned...

Offline J-man

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Re: Vacuum value at idle (rough idle problem).
« Reply #21 on: 05 May, 2016, 10:49:09 PM »
Edit: so it must give 3.5 bar no matter rpm? Or is that just 1 point of reference?
« Last Edit: 05 May, 2016, 10:57:32 PM by J-man »

Offline Marudny

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Re: Vacuum value at idle (rough idle problem).
« Reply #22 on: 05 May, 2016, 11:44:29 PM »
*Originally Posted by rarch [+]
Well done.

I've heard of pumps with internal strainer/filter getting clogged up which reduced the fuel flow, symptoms were lack of high speed but bike could maintain a constant lower speed.

Do you have any idea what would cause a pump to deliver at a higher pressure, could it be a blocked pressure relief valve within the pump?  Maybe it can be cleaned...

All constructions I've met are designed with external fuel pressure regulator (which is vacuum operated - to increase fuel pressure). Relief valve is only a kind of safety valve. It's my first time with return less fuel system.

In CBF fuel pressure regulator is in the pump assembly, probably relief valve does FPR function. If not, there should be fuel pressure regulator. Pump always deliver higher pressure (typically 5 bar). After pump is FPR which regulates pressure. It's very simple construction - spring and diaphgram. Spring weakens with time and FPR delivers higher pressure than set.

I'll check at the weekend :)

*Originally Posted by J-man [+]
Edit: so it must give 3.5 bar no matter rpm? Or is that just 1 point of reference?

Service manual says 50 psi at idle. It's very hard to measure fuel pressure while riding :) But pressure is constant in all conditions, flow is higher while riding (injectors have longer opening time).
« Last Edit: 06 May, 2016, 12:29:05 AM by Marudny »

Offline Mark91

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Re: Vacuum value at idle (rough idle problem).
« Reply #23 on: 21 May, 2020, 10:31:43 PM »
Hello,

Yes, I know, the Honda does not recommend the throttle body sync, but has anybody tried to do it?
What is it the correct method ?

Thanks.

 


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