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[Dan_Lockwood]

Hello again.

Here's another one of my off the wall questions.

I'm thinking of an application that would require an electric fuel pump on an Ultima V-twin with a Mikuni carb.

I know on street rods we used a lot of electric fuel pumps and some of the carbs could handle more psi than others.  The lowest is for the Edelbrock at around 4 psi and the Holleys could take upwards to 7 psi without leaking over at idle.

So when gravity fuel systems for carb'd motors, what do most people use for an electric fuel pump and how much psi can the cycle carbs handle?

Thanks in advance for what I'm will be great information...

[Dan_Lockwood]

What, no one can help me out with answer?

[Twolanerider]

Used an electric pump in a remote tank application on a carb'd bike several years ago Dan.  Was helping a guy build up a long distance bike.  How his bladder managed I'll never understand.  I used a little pump from Mr. Gasket.  Just did a quick search and think I found the same thing.  Take a look at the following link:

http://www.amazon.com/Mr-Gasket-42S-Electric-Fuel/dp/B000BWE4RC

[Dan_Lockwood]

Used an electric pump in a remote tank application on a carb'd bike several years ago Dan.  Was helping a guy build up a long distance bike.  How his bladder managed I'll never understand.  I used a little pump from Mr. Gasket.  Just did a quick search and think I found the same thing.  Take a look at the following link:

http://www.amazon.com/Mr-Gasket-42S-Electric-Fuel/dp/B000BWE4RC

Don, thanks for the reply.

I guess what I'm worried about is how much pressure the needle and seat can withstand.  As I said in my original post, I know not all carbs are created equally in respect to fuel pressure.

I would imagine that 2-3.5 PSI, 42 GPH would be more than enough to feed a 2L V-twin under normal driving conditions.  If you didn't have any issues, this pump looks like a great option to go with.  I have a new Holley pump in my left overs from my streetrod days.  It's a 6 psi / 140 gph pump, but my application was for a 540" BBC with 900 cfm 660 hp motor.

Thanks again and at least I have something that I know would work.

Also I have a customer down in Joplin, Graham Packaging next to the Jasper plant, that has just ordered a new line from us.  I'm thinking that I might be the person coming down to do the startup some time late August.  If so, I'll let you know and maybe we can break bread together again.

Have a great day.

[Dan_Lockwood]

Man Don, I just noticed your post number...  I knew you were up there, but 44k+, that's rediculous!

I see an average of 12.829/day.  I can imagine days when you had to crank out close to 100/day.

The bottom line is that your posts have helped me tons and I'm sure many others as well.

    

[Twolanerider]

Don, thanks for the reply.

I guess what I'm worried about is how much pressure the needle and seat can withstand.  As I said in my original post, I know not all carbs are created equally in respect to fuel pressure.

I would imagine that 2-3.5 PSI, 42 GPH would be more than enough to feed a 2L V-twin under normal driving conditions.  If you didn't have any issues, this pump looks like a great option to go with.  I have a new Holley pump in my left overs from my streetrod days.  It's a 6 psi / 140 gph pump, but my application was for a 540" BBC with 900 cfm 660 hp motor.

Thanks again and at least I have something that I know would work.

Also I have a customer down in Joplin, Graham Packaging next to the Jasper plant, that has just ordered a new line from us.  I'm thinking that I might be the person coming down to do the startup some time late August.  If so, I'll let you know and maybe we can break bread together again.

Have a great day.

A visit would be great Dan.  Always welcome.  Since it'll be work you'll likely not be on two wheels.  That's ok.  We'll put you on the Road Glide or the Road King to go for a ride if there's time.

I remember at the time I used that fuel pump not being able to find a spec for needle and seat pressures for the Mikuni carb that was on that bike.  It's been awhile and I'd not trust my memory for the details as to the effort expended but this was pre-effective-internet so the search was no doubt limited.  Looked a bit at different fuel pumps and this was the option I was most comfortable with.  Fortunately it worked fine from the outset.  I knew of that bike for at least the next three or four years and the guy took it long bladder straining distances.  Fortunately there was never an issue with it.

The pump was used as feed to the carb.  It wasn't just a transfer pump to the stock tank.  The owner wanted the hookup to be standard gravity feed from the stock tank and the remote tank T'd in with a valve.  When the stock tank hit reserve he would then switch via an inline valve to the remote tank.  He wouldn't go immediately to reserve on the main tank as his intent was to actually keep that in reserve.

[sadunbar]

Hello again.

Here's another one of my off the wall questions.

I'm thinking of an application that would require an electric fuel pump on an Ultima V-twin with a Mikuni carb.

I know on street rods we used a lot of electric fuel pumps and some of the carbs could handle more psi than others.  The lowest is for the Edelbrock at around 4 psi and the Holleys could take upwards to 7 psi without leaking over at idle.

So when gravity fuel systems for carb'd motors, what do most people use for an electric fuel pump and how much psi can the cycle carbs handle?

Thanks in advance for what I'm will be great information...

Some years ago, I saw a set-up once where a guy had fit an EVO V Twin with a Mikuni carburetor to power a boat.  He had a remote fuel tank which required an electric fuel pump to pump the fuel from the tank thru a regulator to the carburetor.  I asked about the setup.  He explained the electric fuel pump flowed to a Y connector - one fuel hose went to the carburetor and the second fuel hose was a restricted return line to the fuel tank.  I don't know the details of the restriction. He was running 3 psi at the fuel regulator.  He explained that at idle more fuel flowed thru the return line to the fuel tank and at throttle, less fuel flowed thru the return line to the fuel tank.  I assume the restriction in the return line was very specific to the application and controlled this aspect.  I don't know what the resulting fuel pressure was at the carburetor (on the needle and seat), but I suspect something close to 2 psi.  I don't know if the Mikuni had a stock needle and seat installed, but I know various needle and seat assemblies (with varying flow rates and spring pressure) are available from Mikuni.

[Dan_Lockwood]

Thanks guys, I appreciate the input and experience shared.

Don, I'll keep in touch if I'm the one coming down and give you a heads up.

[2018_FLTRXSE]

I just saw this...

The above comments are similar to what I recall... http://www.amazon.com/Facet-1024AMZ4121-Electric-Fuel-Pump/dp/B000P4Q5IW

Facet pumps are what we used to use. No real need for a return system... but a small adjustable regulator was common... I think we used one from Mr Gasket back in the day.

[Dan_Lockwood]

I just saw this...

The above comments are similar to what I recall... http://www.amazon.com/Facet-1024AMZ4121-Electric-Fuel-Pump/dp/B000P4Q5IW

Facet pumps are what we used to use. No real need for a return system... but a small adjustable regulator was common... I think we used one from Mr Gasket back in the day.

Thanks for the information.

A lot of the newer regulators have a return line built in.  This keeps the pump cooler rather than letting it just build head pressure and load up a bit.  Either way it's not a big deal on the pump.

Thanks again to all for your comments and experiences.

[Owner of Skye]

my 2003 Suzuki Intruder 1500 used a fuel pump on the carbureted bike -- you might look at the that -- the tank was under the seat --G-Man Industries also made an auxiliary tank under that to gain more distance -- made a 4 gallon bike into a 7 gallon. You might want to check with G-man to see what they say about fuel pump pressure