SparkFun Forums

[smartroad]

Hi All!

I want to make an MPG display for my motorbike. Unlike most modern cars it doesn't have an OBD-II system, so I need to measure the fuel flow directly. I remember reading that SparkFun sold a fluid flow sensor but I can't find it now, but I also thought it couldn't do petrol.

Anyone know of a sensor that would be able to measure the flowrate of petrol?

[lyndon]

Are you thinking about this?

I don't think Sparkfun has ever carried it. It's not spec'd for gasoline; in fact, it doesn't seem to be spec'd for anything other than water, but you can try it. I have a couple and they work very well, but at 1 liter/minute minimum flow rate, it's too high for a motorcycle. Maybe if you were running a 16-cylinder diesel it would work

In any case, flowmeters for diesel and gasoline are usually very expensive, around $1,000 or so. A better way to measure flow on a small engine would be to count fuel injector or mechanical fuel pump pulses.

[Mee_n_Mac]

Are you thinking about this?

An interesting part in it's own right but am I manifesting a brain tumor if I recall a smaller inline sensor, like something that might be used in a 'puterized bar ? Mebbe that was a different site too ???

[UNTEngineer]

Two things Id like to input: First, if you tamper with or add anything into the fuel line, make sure it is safe to do so and legal to do it! If you go and get an inspection with this gadget in there, they might (might!) fail you.

Second is, I found plenty of cheap flow meters on ebay (http://r.ebay.com/NhyieE), but as this deals with fuel and potentially your life, I wouldnt go cheap, and I wouldnt do this myself. Find yourself a good mechanic who would be willing to take the job, and invest in some reliable technology to get the job done right, and not just on the cheap.

[lyndon]

They make that sensor in smaller sizes also. I've seen it for down to 1/8" tubing.

Are you thinking about this?

An interesting part in it's own right but am I manifesting a brain tumor if I recall a smaller inline sensor, like something that might be used in a 'puterized bar ? Mebbe that was a different site too ???