Fuel pump activation on kickstart motorcycle
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Fuel pump activation on kickstart motorcycle
I have a microsquirt setup on my ‘85 Yamaha RZ350, which is a kickstart motorcycle. When I kick the bike over to start up and the RPMs are synced the fuel pump comes on as expected. However, they are only a few rotations of the crank with each kick before the fuel pump shuts off again and fuel pressure drops. I would like a set up where the fuel pump is running continuously without having to kick the bike over, so that when the RPMs sync (plugs fire and injectors open) there is already fuel pressure in the rail. The only way I can see to accomplish this is to install a manual toggle switch to send 12v direct to the fuel pump to run it, bypassing the microsquirt control of the fuel pump. Once the engine is running I could then turn off the toggle switch and the fuel pump should continue to run through microsquirt control.
Does anyone have any other ideas of how I could accomplish this?
Thanks
James
Does anyone have any other ideas of how I could accomplish this?
Thanks
James
EFI and Turbo Yamaha RZ350
Microsquirt with MSExtra 3.3.2
Microsquirt with MSExtra 3.3.2
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Re: Fuel pump activation on kickstart motorcycle
You just need to run an extra wire to same point on the fuel pump relay that the microsquirt is connected to, and run a switch to ground to manually turn on the pump.
-Dave
-Dave
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Re: Fuel pump activation on kickstart motorcycle
Something is perhaps a problem here. With normal OEM setups there is a non-return valve in the pump and pressure is retained for weeks.sweet_baby_james wrote: and fuel pressure drops.
James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk
My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
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My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
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Re: Fuel pump activation on kickstart motorcycle
So maybe a small check valve is needed on the rail side of the fuel pressure regulator?
James
James
EFI and Turbo Yamaha RZ350
Microsquirt with MSExtra 3.3.2
Microsquirt with MSExtra 3.3.2
Re: Fuel pump activation on kickstart motorcycle
usually a check valve at the pump outlet is all thats needed (or pretty much anywhere between the pump outlet and rail)
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Re: Fuel pump activation on kickstart motorcycle
Was just about to reply before I saw this.jsmcortina wrote:Something is perhaps a problem here. With normal OEM setups there is a non-return valve in the pump and pressure is retained for weeks.sweet_baby_james wrote: and fuel pressure drops.
James
Yes there should be plenty of fuel pressure after priming that this should not be an issue.
An in-line non-return valve sounds like it's required.
Edit: it's either that, or the regulator is bad.
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Re: Fuel pump activation on kickstart motorcycle
How long should a fuel pressure regulator be expected to hold pressure in the system?
EFI and Turbo Yamaha RZ350
Microsquirt with MSExtra 3.3.2
Microsquirt with MSExtra 3.3.2
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Re: Fuel pump activation on kickstart motorcycle
I've undone hoses on a car that had been on a scrapyard for months and got sprayed by fuel.sweet_baby_james wrote:How long should a fuel pressure regulator be expected to hold pressure in the system?
James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk
My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
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Re: Fuel pump activation on kickstart motorcycle
Oh, by the way;
When I first injected my RZ500 I had a lot of trouble replicating the choke on a 2stroke.
I really wanted the priming pulse to be triple the default maximum.
For a while, I was turning the key on/off/on a few times before I would attempt the first kick so it would fire.
When I first injected my RZ500 I had a lot of trouble replicating the choke on a 2stroke.
I really wanted the priming pulse to be triple the default maximum.
For a while, I was turning the key on/off/on a few times before I would attempt the first kick so it would fire.