Z650 Fuel Economy MPG

[Zebedee]

After my trip to the Ace Cafe at the weekend and the shortage of premium fuel at petrol stations, I was wondering what the collected wisdom was with relation to expected MPG?

I had to fill up on the way down and also again on the way back up and having just passed the High Wycombe slip it was touch and go to make it to the Oxford services (ouch)
Anyway calculated mpg when home and its nit very good.

Circa 20 mpg.

What should I be expecting?

Okay was in traffic and at speed on the motorway so 70-ish most of the way, but 20 seems a bit low?

Thoughts?

[warren3200gt]

20 is caning it mpg. 35 to 40 should be achievable on normal riding depending on engine air and exhaust set up.
Motorways are not good on 650's with standard gearing which is fairly low.

[KeithZ1R]

20 is caning it mpg. 35 to 40 should be achievable on normal riding depending on engine air and exhaust set up.
Motorways are not good on 650's with standard gearing which is fairly low.

............................ ............^^^^^ ^^^^^ this, the gearing is painfull on motorways

[zapo]

Are you sure it's not leaking out!
My B1 used to do 40 to 45 mpg, two up, mixed riding including commuting.
70 mph was at 6000 rpm.

[Zebedee]

Well Officer I was keeping up with traffic and for safety sake I had to overtake a couple of times (load on the vehicle ahed looked decidedly unstable) so changed lanes and needed to keep up with traffic in that lane so 70 plus from the de-restricted sign on the A40 where it becomes Motorway to when it started showing signs of lack of fuel (about 12 miles south of Oxford services).

On the plus side apart from £1.91.9p for BP ultimate at the services it didnt take long to get home.

[Zebedee]

Done the maths and 106 miles and admittedly expensive fuel but 25 litres £ 46.48
Yikes!

[chrisu]

Are you sure it's not leaking out!
My B1 used to do 40 to 45 mpg, two up, mixed riding including commuting.
70 mph was at 6000 rpm.

absolutely this ^^^^^

[Zebedee]

So some more accurate measurement of fuel and mileage and also inspection of plugs and I dont believe I have a leak but it is running rich so ive wound out the air screws a half turn on each carb.
Last two fill ups ive averaged 15mpg so maybe its the gearing and my approach to speed?
Anyway illl see what the leaner mix does and hurry up with the Z1000 build.

[zed1015]

So some more accurate measurement of fuel and mileage and also inspection of plugs and I dont believe I have a leak but it is running rich so ive wound out the air screws a half turn on each carb.
Last two fill ups ive averaged 15mpg so maybe its the gearing and my approach to speed?
Anyway illl see what the leaner mix does and hurry up with the Z1000 build.

The air screws only affect the pilot/idle a/f ratio so you are only leaning off up to around 2000 rpm and it won't correct overfueling elsewhere.
I5mpg is horrendous mileage and akin to having a hole in the tank.
If all other carbs settings, jets,fuel heights are correct and the motor is in good nick you should look at the condition of the choke plunger seals as these are prone to leaking fuel.
Several owners have reported gains of 15 to 20mpg from having the plungers repaired.

[Zebedee]

Yes I think that Its plunger time.
Ive leaned off the air screw as the plugs were well rich, that and teh mpg.
I'll see how that rides and tinker from there.
I do intend to re-redo the carbs when the good riding is over and hopefully by then the z1000 will be closer to finished too.