Query approved.

what is your method of checking on road mileage.........???

@ravi: The mileage tests you have done doesnt give exact figures.. itz just a calculation.

at what speed or rpm range are you getting your mileage,

b/w.. as PRINCE asks how do you check the mileage? since 20kmpl difference is possible only if the clutch plates are burned... and that can be observed only at higher rpms.
How did you perform the running-in process

i suppose you are not depending on fuel indication on the dial for calculations...

Make your tank empty, that is ride till it stops, (there can be some fuel left, and that is the unusable part) and add 1L, ride and test. or else fill your tank 1L above reserve and check. (do alwayz keep some fuel with you as spare )

If the same persists...

Give your carburetor for cleaning, ask them to check the mainjet and the clutch

If the mainjet is tampered it can sent more fuel than required at higher rpms (but still it wont give 20kmpl difference)
How many service and kms did you cover, and tell us how you change gears, hope you dont maintain riding a gear less than the top gear
and ask him to check whether you are using the same carburetor your bike should be using.
these all are rare chances as your bike is new...

Mileage test on 100 ml petrol will not give exact mileage figures. It differ a lot from everyday start, stop heavy traffic or high speed ripping and riding. Explain them about that.

The carburetor needs to be tuned properly. Service center people always mess up with this tuning..

If you want to know the exact mileage then empty the tank. Fill atleast 3 litres of petrol and ride it till it comes to an end. This will give the most accurate figures.

If your bike is still in run-in process then i advice you to wait until it crosses 2000 kms, to worry about mileage. Because the mileage will improve after proper running-in .

First of all check your petrol bunk/filling station if they are filling exact volume of petrol.
Amateur mileage testing.
make your own mileage testing can, because when the service center people use their can & if there is any error in its volume reading, the mileage error also magnifies by 10 fold. because they multiply 100ml by 10 right.
Take a pet bottle(your fav soft drink), buy 1 meter of petrol pipe, make a hole in the cap and insert the pipe real tight, make a small hole at the bottom with a pin, use a plaster or cellophane tape to cover the hole.
Fill it with 100ml of petrol.
turn off the fuel, remove the fuel pipe, ride the bike until it gasps, use choke to burn every single drop of petrol in the carburetor bowl. now connect the pipe of your bottle, invert the bottle, remove the plaster to let air in, wait until the petrol flows into the carb, ride. you need a friend who can hold the bottle.
1. Highway testing(constant throttle at midrange or economy range)
2. City traffic conditions.
before testing, make sure the correct tyre pressure is there, make sure the airfilter is clean, chain tension is checked and well lubricated, engine oil is good(svc center guys sometimes don't change the engine oil but gives you bill for oil change)
Log your recordings, test different configurations of air/fuel screw turnings etc, come to a conclusion.
I get 63 on highways and 51 in city conditions on my unicorn

sorry for being OT but thats one crazy method

Thanks a ton guys for the replies. Here is the method I used for testing mileage:

1. Reset the trip meter to 0 when the bike goes into reserve.
2. Fill petrol varying from 1 to 4 liters (I've bought petrol in bottles to overcome the suspicion that bunk guys dispense less petrol).
3. Run till the bike goes into reserve again.
4. Note the trip meter and calculate mileage.
5. I have repeated the process at least 20 times and got to the same average.

Is emptying the tank necessary or reserve-to-reserve serves the same purpose.

Riding Condition: City riding.
Current Odometer reading: 2600 km.

@ARNandal - Thanks a lot for the insight into what can cause the dip in mileage. However, if those things are causing dip in mileage, then I should get same low mileage while testing with the can at service center.

The confusion is how service center test gave 60 kmpl and my road test gives 40 kmpl consistently. In both, the road conditions were same, city riding with lot of traffic.

The only reason I can think of is that their can is tampered.

Are you guys aware of any mechanic/Honda service center who can assess the problem properly.

Reserve to reserve will serve the purpose, but would be approximate but definitely wouldnt give more 800ml of variation.

Clear all these questions..

> Have you done any modification on your bike?
> how did you perform the running-in process, did you follow the riding instructions like speed limit & rpm limit on each gears....?
Improper running-in can affect mileage.
> most common speed and rpm you maintain during your daily rides?
> Did you change the engine oil after the first 500kms run?
> Which Engine oil are you using? did you fill it up or the service centre?
> Does your engine overheat
> Does your Engine knock, or do u feel less power or acceleration?
> do u feel any hiccups or sounds or uneven or not smooth ride, when accelerating.
> place your vehicle in centre stand rotate both the wheels and check whether they move freely or not
> do u feel your bike accelerating by sound and not moving.
> do you experience hard gear shifting?
> Did you see the mechanic removing the carburetor, or did he just did tuning using the screw driver
> is this the first time you are riding a bike?

2600km on the odo is high time your bike should be giving good mileage.
Tell us with on all the above queries and we will help you with a way to get the issue sorted.

someone stealing petrol?
petrol evaporating from cap?

Test mileage using my method, don't confuse yourself too much.

First of all how many kms has your bike done ??
Its just 1st service done , right ? So better hold your horses. Unicorn engine gets smoother and delivers better with time.

@Shreeni0403: His bike has clocked 2600km, and i think itz high time he should be receiving reasonable mileage... 40kmpl is not reasonable..
Though am not been on Honda bikes...

Thanks ARNadal for the interest in helping. Here are the answers to the questions you posed.

But will reserve-to-reserve average over multiple (say 20) readings be accurate. I've taken approximately that many readings.

> Have you done any modification on your bike?
None.
> how did you perform the running-in process, did you follow the riding instructions like speed limit & rpm limit on each gears....?
Improper running-in can affect mileage.
I didn't give much thought about rpm/gear-wise speed limit, but I did not go beyond 40 or strain the bike for the first 600 km

> most common speed and rpm you maintain during your daily rides?
35 to 50 kmph

> Did you change the engine oil after the first 500kms run?
Yes, first it was changed by service center, but I felt the quality to be poor and immediately changed again with a week

> Which Engine oil are you using? did you fill it up or the service centre?
I'm either using shell or bosch, i think bosch is better

> Does your engine overheat
No

> Does your Engine knock, or do u feel less power or acceleration?
No

> do u feel any hiccups or sounds or uneven or not smooth ride, when accelerating.
No

> place your vehicle in centre stand rotate both the wheels and check whether they move freely or not
They seem to be fine to me(novice eyes)

> do u feel your bike accelerating by sound and not moving.
No

> do you experience hard gear shifting?
I used to get that, but after changing oil myself it seems okay

> Did you see the mechanic removing the carburetor, or did he just did tuning using the screw driver
I gave it to service center and they tuned using screw driver and some kind of meter (small phone like) which showed some number when held near the engine

> is this the first time you are riding a bike?
No

Thanks Sandeep, I'll try it this over next weekend as it requires some work.

Stealing petrol is not an issue as I park mostly at home or office which are protected. Moreover, someone will not steal every time in a way that I end up having a mileage of exactly 45 kmpl.

Evaporating from cap can be a possibility. How can that be checked?