Low MPG (Km/L) problem

[Quinnston]

Hi, I had a search about this but cant really find a good answer and was hoping someone can point me in the right direction..

My bike, Pegaso 650 2002 ie (my 1st bike over 125cc) which I love to bits, has 1 major problem. I fill it up with 10 litres and light comes on like clockwork at about 120km, which is about 35MPG or 8L/100km.

Where do I start? When I took the bike for MOT he recommended me coming here and looking for an answer before they start doing any work on it.

Also there is another problem that has just recently started to happen, sometimes the temperature reading goes to 120oC when I first fire it up. Bike seems to go as usual and reading goes down after riding for a bit.

Would really appreciate if someone can point me somewhere on the low MPG problem though, Cheers.

[stisma]

You pointed yourself in the possible direction by noting the temp variation at start-up.
If the wrong temp reading is send to a CPU it will alter fuel-air mixture to compensate for the temp that.
One or more of the sensors is causing the CPU to .....be confused.

Love the carb version!

[Quinnston]

The faulty temp reading has only just started to happen (since the nice weather (rare in England ) whever that has anything to do with it,) and its only occasionally.

The MPG problem has been there since I got the bike.

[stisma]

In that case an experianced tech with a adequate software is a must.
Something like a sensor, wiring or software is causing the bad MPG.

Keep in mind there are numerous factors for a low MPG...
(intake air leak, exhaust leak, air-filter, fuel injector(s), throtle bodies, ....)

I would visit a experianced shop and start with any codes then sensors.
Any cost will pay for itself in fuel savings. It's a win-win!!!

[Quinnston]

Thanks for the advance, Stisma

[Vicki M]

Mine is 2004 ie. I get huge difference in mpg / km/lit between round town running and open road running.
Round town warning light comes on at 120 - 130 km from full tank, on a run I easily get twice that (abt 54 mpg, I estimat I would get nearly 400km inc reserve from a full tank). On a mix of mostly round town and say a shortish 20 km run at w/e, I get about 180km from full tank to warning light.

cheers
Vic

[Almiaman]

Hi, My 03 650 IE just returned 6.7L/100 after all commuting use.
Temps -3 to 3 and only 11 Km trip. I had been concerned as it does not get real warm in that time.
Gauge reads about 60C. Light came on at 200 Km and it took 14.5 Ltrs Obviously I need more tanks through to get
an average.
I was not impressed but after reading this thread I will hold off doing anything rash until I know more.
Thanks for sharing it is the best way to build the knowledge base. Regards, Al

[fitzyt]

Hi, I get off 14.5 lts 290 on average, I would of thought your model would be a bit better being injection....Regards Tony

[Almiaman]

Hi, Further info.
Two more tanks of commuting in zero to 8C temps for 11 kms each way.
5.31 l/100 and 5.53 l/100. The fuel light comes on around 245km.
The exhaust accumulates heavy soot around the tips and on the licence plate.
I expect the consumption will fall once I get to do a trip, particularly, as the weather warms into spring.Regards, Al

[bluesplayer]

Dunno what my model is but its a 1996 650 . I get high 20s mpg sometimes mid 30s . The bike is running super rich , black soot and smoke , My local bike shop says the Float valve is shagged . So im replacing all seals and valves . The kit costs £29.99 and you need 2 . My bike shop assures me everything will be fine when its done . I will let you know the out come .