Can anybody tell me as a rough guide what fuel pressure to dial in to my regulator for cb600 carbs drilled out to 1.5mm, currently my regulator is set at 3 as I used to have a weber dgas but it can go upto 6 if needed.

TIA

Rich

i think the standard bike pumps cut out at 3 and a half psi, so i'd imagine if you leave it as it is, you'll be alright

tom

You need only about 1 psi, too much and they will flood. What size engine have you got? about 1.7 is a good start for a 2l.

1.6 pinto, just had a look at my notes and actually drilled jets out to 1.6mm.

So think they should be ok, I'll knock down the psi and see what happens.

Cheers

Rich

[Edited on 10/2/08 by RichardK]

If you run into problems it may be best to buy a carb engine bike fuel pump.

Regulating pressure down so low can strangle flow to on most pumps, many have fallen foul of this one looking for running problems that are actually fuel flow problems.

When you say reg is set at 3 i assume this is number 3 and not 3 psi.

I fitted bike carb fuel pump and not had any issues at all (no regulator). Ive been told facet solid state pumps are ok too.


I once had a red top facet on the car, tried to regulate it down for a 38DGAS and it didnt work at all. The pulsing effect of the pump forced fuel passed the reg and flooded carbs. Mechanical pump fixed that issue.