high fuel consumption and some weird stuff - Page 2 - .: XT660.com

sime · # 11 09-07-16, 14:12

First check all the simple stuff.
Make sure the valve clearance is right and the air filter is clean.
Spray some brake cleaner around the throttle body to see if there are any vacuum leaks. The engine rpm fluctuate if there is.

Check the spark plug this will give a good indication on how the engine is running black is to rich.

Also check the electrical components resistance. Injector, tps etc... the correct values are in the workshop manual and Haynes manual.

In my case I had a ground problem on the injector cable under the tank.
Remove the tank and check the cable for wear and tear maybe it is making contact on the frame.

If this is the case the injector will always give a full blast of fuel resulting in bad running, black smoke, fuel smell from Exhaust and off course bad mileage.

Verstuurd vanaf mijn Nexus 5 met Tapatalk

Snakeboy · # 12 10-07-16, 07:17

Quote:

Originally Posted by sime

First check all the simple stuff.
Make sure the valve clearance is right and the air filter is clean.
Spray some brake cleaner around the throttle body to see if there are any vacuum leaks. The engine rpm fluctuate if there is.

Check the spark plug this will give a good indication on how the engine is running black is to rich.

Also check the electrical components resistance. Injector, tps etc... the correct values are in the workshop manual and Haynes manual.

In my case I had a ground problem on the injector cable under the tank.
Remove the tank and check the cable for wear and tear maybe it is making contact on the frame.

If this is the case the injector will always give a full blast of fuel resulting in bad running, black smoke, fuel smell from Exhaust and off course bad mileage.

Verstuurd vanaf mijn Nexus 5 met Tapatalk

Thanks for input. I have checked all you mention except the injector and electrical components - which ones do you mean by the way? I have had a garage to check via the diagnose system - but nothing was found.

And as I mentioned in my last post - I have also had the exhaust checked and it was very very near perfect. So that should mean that I can rule out injector, censors and engine as a whole - I presume, and start to look for something else....

Its so damned irritating that I earlier on easily could get 25 kms pr liter - 70 mpg without thinking about saving fuel and nowadays I can get only
20-22 kms pr liter - 55-60 mpg - constantly riding in fuel saving modus at max 90-95 km/h.....

Nener · # 13 27-02-17, 09:59

Hi there,

I have a similar trouble now... almost +20% fuel consumption if i compare to when i bough the bike.
So i fitted kev O2 and fuel mods, as well as dna air filter... but that was way before the consumption went higher. Tryed with the fuel mod set to 0, no change.
Filter is clean. Spark plug looks ok, i'd say the bike runs fine except for the consumption.
I also added an aftermarket exhaust (i can't see that increasing fuel consumption that way, plus it has no cats now...)

What may play a role is that i fitted a slightly bigger and less street oriented rear tire. I can see that decrease my mpg as i look at the odo to calculate it+ dirt tire will waste more energy on the slab. But not THAT much

Any idea what to look for, before i give a shot at putting everything back to stock (remove kev mod, stock filter and snorkle, stock exhaust) ?

SimonRoma · # 14 27-02-17, 15:04

I have always used a fuel system cleaner in the petrol every so often, like STP or Redex or similar. I think that this helps to keep the injector system clean. Simply add to the fuel tank when you fill up.

SimonRoma · # 15 27-02-17, 15:13

And ps I used to get 20 km per litre from my XT660X, riding it as fast as possible. 15 is terrible.....

Nener · # 16 27-02-17, 17:31

Thanks for your reply. Yes 20km/L was the worst i was getting at first. Now i'm always under that.
I'd say consumption has been increasing slowly... so i will make a try or two with curative fuel cleaner.

Pleiades · # 17 27-02-17, 20:02

Quote:

Originally Posted by Nener

Hi there,

I have a similar trouble now... almost +20% fuel consumption if i compare to when i bough the bike.
So i fitted kev O2 and fuel mods, as well as dna air filter... but that was way before the consumption went higher. Tryed with the fuel mod set to 0, no change.
Filter is clean. Spark plug looks ok, i'd say the bike runs fine except for the consumption.
I also added an aftermarket exhaust (i can't see that increasing fuel consumption that way, plus it has no cats now...)

What may play a role is that i fitted a slightly bigger and less street oriented rear tire. I can see that decrease my mpg as i look at the odo to calculate it+ dirt tire will waste more energy on the slab. But not THAT much

Any idea what to look for, before i give a shot at putting everything back to stock (remove kev mod, stock filter and snorkle, stock exhaust) ?

What fuel are you using? 95RON? 97/98RON? E5 or E10? The latest E10 fuels (10% ethanol) will contribute to higher fuel consumption as ethanol has a lower energy content than petrol. The more ethanol the higher the fuel consumption will be for any given engine/road speed.

As they are sneaking up the ethanol content in forecourt petrol every year it is quite plausible that you are finding your bike's mpg gradually getting worse. Nine years ago here in the UK (when I bought my XTZ) the vast majority of petrol was E0 (no ethanol). By the end of 2018, when my bike is ten years old, it will almost all be E10, a completely different fuel from that the XT was originally designed to run on.

Nener · # 18 27-02-17, 20:55

I'm aware of that. In France we get 98/95/95 E10. I try to get them in that order of priority. I think SP98 and SP95 have 5% ethanol though, but that's not new.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode