SV fuel pump...

[Hawk Jr]

I switched over to this and now I am having some fuel issues when I really gun the bike.

Lets say i tear ass off in 1st to redline then 2nd then to 3rd... the bike will begin to sputter and backfire and lose major power... give it 30 seconds and then the bikes fine... It will aslo do this when I am on the hwy and try to exceed 85mph. I will lose power, sputter and almost die.

Anyone else had this issue w a SV 650 fuel pump?


Rob

[MrDude_1]

make sure your vacuum power hose is not "squishy"... if its getting sucked flat, the pump wont pump.



edit:
for the record, the SV pump will support more power(fuel flow) then your hawk motor can make.. so you shouldnt have a problem.

[Hawk Jr]

Yea I know... I had to replace it with a hard line back when I put the pump on. I was using fuel line at first and it did suck flat and kill the bike so I replaced it with a hard line like used on water lines for ice makers.

rob

[MrDude_1]

well.. that kills my idea. lol.

where do you have the pump mounted?

[drinmotoracer]

I was actually wondering about the SV pump... I mean is it really that much better? Does it just deliver fuel more efficiently to the carbs?

[SkinnE]

It's smaller and lighter than stock, and doesn't need the electric feed that the stock does. So it's easier to relocate and hide, that being my understanding for this mod.

As far as your problems, back in the 90's a few racers had problems with Mikuni vaccuum pumps on their Hawks. Similar to what you described, sustained high RPM, large throttle openings would bring on fuel starvation problems. Pumps just couldn't supply enough fuel in these situations. Iirc they ended up reverting to stock pumps?

E

[MrDude_1]

I was actually wondering about the SV pump... I mean is it really that much better? Does it just deliver fuel more efficiently to the carbs?

its tiny and reliable... that why i went with it...

but i dont have enough experience to trouble shoot his problem online... mine just works fine.. lol

[DefTrap]

You're absolutely sure it's an SV pump? Even so, there may be some differences in flow rate across models .. maybe. I've got a Yam divvy pump which looks fairly similar. You can get snowmobile ones with twin feed as weel which may be worth a shot.

[Guzzisti57]

I have one of these, only concern is the 6mm fuel hose instead of the 8mm on the standard fuel pump.
It seems weird to go from a 400cc with 8mm hose to a 750 with 6mm hose ...?

We will see ...

[Stevenjhow]

I wanna bump this thread....can someone post a pic or two on where and how the pump is hooked up? where do you get the vacuum from?