Slingy fuel tap flow

[davecara]

B12 engine, RS38's, possibly dot head at some point. Will the standard tap give me enough juice?

[Gixer1460]

Maybe but 140 odd hp against std 100hp is a 40% increase in fuel so . . . . .!

[Fazz711]

On 8/12/2022 at 5:45 PM, Gixer1460 said:

Maybe but 140 odd hp against std 100hp is a 40% increase in fuel so . . . . .!

40% ingress in power is not necessarily a 40% increases in consumption

[Lachie04]

 

 I have been struggling with the same question since putting a bigger motor in the bike and having the bike stutter down the track straight (tbh it may have been a loose spark plug) 

According to calculation 140 hp would require 11.5 gph (100hp would equate to 8.5 gph)

Therefore theoretically if your fuel system can flow better then 12.5 ml/s (12gph) then you should be able to sustain a high speed run 

This is all theoretical and can't be relied upon to be sure so many variables

The answer is really suck it and see

 

 

 

 

Edited August 14, 2022 by Lachie04

[Joseph]

I have a cammed and ported 1216 with RS38. That was fine with the slingshot tap.

I no longer use a tank fitted tap, because nothing seems worth the hassle.

The carbs are fed via a 10/8mm ID fuel hose system and are fine

Bear in mind i don't track it

Edited August 14, 2022 by Joseph

[davecara]

2 hours ago, Joseph said:

I have a cammed and ported 1216 with RS38. That was fine with the slingshot tap.

I no longer use a tank fitted tap, because nothing seems worth the hassle.

The carbs are fed via a 10/8mm ID fuel hose system and are fine

Bear in mind i don't track it

I’ll be pestering you for base settings for the carbs then!

I’m gonna just stick a pingel on it and remember to turn it off. May as well future proof myself

[Gixer1460]

14 hours ago, Fazz711 said:

40% ingress in power is not necessarily a 40% increases in consumption

Improvements in efficiencies will skew the results but 'generally, as a rule of thumb' - 1 bhp needs 'x' volume of fuel in a linear fashion.

[Fazz711]

2 hours ago, Gixer1460 said:

Improvements in efficiencies will skew the results but 'generally, as a rule of thumb' - 1 bhp needs 'x' volume of fuel in a linear fashion.

I can only go off what I have personally seen.

Me and a mate both had EFEs dynoed on same day same dyno.

Mine made 118 but his 108 bhp.

Through constantly running about together mine was 10 -20 % better on fuel consumption.

We did a lot of riding together that summer and it was always the same

Edited August 14, 2022 by Fazz711
Garmin auto correct lol

[Captain Chaos]

4 hours ago, Fazz711 said:

Through constantly running about together mine was 10 -20 % better on fuel consumption

could be your riding style is more economic.

Last year I took my boss' car to Holland and back (in total 3200 km) and my average speed was higher and fuel consumption lower than when he drove it on the same trip.

[jonny1bump]

I've seen 5 hp increase on dyno pushing end of stock fuel tap in, generally they not very good especially with age of them now.

[Fazz711]

21 hours ago, Captain Chaos said:

could be your riding style is more economic.

Last year I took my boss' car to Holland and back (in total 3200 km) and my average speed was higher and fuel consumption lower than when he drove it on the same trip.

Could be but at the time 20 + years ago we were both considered to be nutters lol

[Joseph]

I do 45 mpg average on long trips with above said set up.

Again, i don't track it, it just gets some occasional thrashing

[Simbec1863]

I used an R6 one on my 600 blandit race bike not sure on hole spacing for your fitment.

it was a larger bore and had on off function was a cheap upgrade for racing 

Edited August 16, 2022 by Simbec1863