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Anyone know how much psi a good fuel pump has. I want to test my pump--I suspect it is weak as the engine is starving for gas at the high end--6-7 thou rpms. Also where can I find a pump to replace mine if needed? So far I have not been able to locate one. The volume test is hard to do--can I just do a psi test??
I heard that a vf700 or 750 or honda civic fuel pumps would work??? Also heard a 4psi 12vdc round pump at advance auto parts would work??? What do you think??

A 1984 Honda VF500C (V30) does not have a fuel pump. It could have an aftermarket FI system on it, which would use a fuel pump. Bike Bandit or Old Bike Barn is where I'd look.

Johnj wrote:A 1984 Honda VF500C (V30) does not have a fuel pump. It could have an aftermarket FI system on it, which would use a fuel pump. Bike Bandit or Old Bike Barn is where I'd look.

Re-check your info--I have a pump and relay stock--wish it did not have a pump--my life would be a bit easier--my manuel gives a volume test which was a bit short of specs--so I am looking for a new pump but was wondering how much output psi I need--I heard 4 psi but I want to be sure.

Oh ya, the VF500C has that little bitty aux tank under the seat. Do not use a pump designed for fuel injection. Does your pump flow the required volume of fuel?

Johnj wrote:Oh ya, the VF500C has that little bitty aux tank under the seat. Do not use a pump designed for fuel injection. Does your pump flow the required volume of fuel?

Yes but I am going to retest today to confirm volume--my last test was done with the engine running fuel line off carbs--today will run test following manuel instructions--jump relay--turn key on--should deliver 0.74qts--test is for 10sec times 6=1min=0.74qts plus or minus 0.10

With engine running I got 4oz x 6=24oz=3/4ths of a quart--right? so it passes--I want to retest using book method to see if I get the same results. This test method is much more difficult cause the relay is hidden in there--hard to get to--my reason for testing by simply removing fuel line and run engine with float bowl fuel.

If the fuel pump passes again--Im back to square one with my problem of crapping out at 6 to 7thou rpm's.

Let me run this next idear by you--one of my coils had a crack in it along its side--I put rtv over it to keep moisture and dirt out--if this coil is weak--could it be causing the crapping??


A bit of history so we don't backtrack too much--carbs off 3 times cleaning and making sure the sliders are working right and diaphrams checked for tears or holes-- set in there grove--new boots--carbs put on engine all the way seated and boots tight and tested for leaks--air cleaner cleaned and oiled with proper oil (K&N clean kit)--new njk plugs--engine oil and filter new--checked tire pressure (joke--ha--ha)--sync carbs with mecury manometer (all four are near perfect after painful messing with butterfly's--hard to reach until my neighbor let me use his 45 degree super screwdriver with a twist tube thingee)--bike will haul butt if I change gears around 5 to 6thou rpm's--cruises fine under 6 and reaches 55 to 60mph at 5thou. With the tac at 5 to 6 thou and speed at 55 or 60 mph and I open the throttle up--thats when the crapping starts. A thought just happened--maybe I need to downshift a couple of gears before opening her up??? Mabee it is simply lugging??? Have to try this.

Not an answer, I'm afraid but can anyone tell me where I can find a fuel pump for a 1985 V30 VF500C?