One more query . For a 4 stroke two wheeler what are the other major things that I need to check for mileage apart from carburetor and tuning it.

So that I can rule out all the issues.


Thanks

1. Good Clean Air filter
2. Good Quality Petrol
3. Correct Valve clearance(tappet) setting
4. Correct grade of Quality Engine Oil.
5. Good correct spec Spark Plug, and it's connection
6. THE MOST IMPORTANT FACTOR....GOOD RIDING STYLE...not doing sudden and sustained high acceleration at lower gears.

As PSR jee told I did and tested my bike last saturday. It gave me 47kmpl. But I was driving in highways where I stood stead between 40 - 55 kmpl.

And one more test I did in shakthi bajaj on tuesday morning.He tuned my bike. then he did MRTB test.

1st he placed my bike in the test bench he drove it for 117kmph . I think that s the max speed. Then he switched off my petrol flow and plugged out the fuel pipe and connected to that MRTB machine then he drove my bike in the test bench with 40 - 50 speed. within one minute it showed the fuel consumption as 57kmpl. He told that this bike wud give 50 - 52 kmpl.

He didnt drain the carb before testing and the bike was also not jerking during the test ended. He told 57kmpl in the machine means on road it shud give 50 - 53 kmpl.

One more thing - I have changed a new air filter.
I wish to know what is that tappet valve clearence. How to check is it in the correct adjustment. where it is located.

pls pass on the comments abt mrtb test

Tappets are located inside the cylinder head cover of the engine. They are to be adjusted to the specifications in the service manyal which is 0.05mm for inlet Valve and 0.1mm for the exhaust valve

for more information, visit this thread


The process is more or less the same for pulsars too.

What is an MRTB test. I did that for my bike. How do I calculate the mileage that it shows as 57kmpl in that test bench.

Just a quick check since we are in this topic, i just got hold of a 2004 model 150 Puslie. I want to tune it to give good response and smoother power delivery as right now i feel it is choking. So from the fully closed position of the AF screw much turns anti-clockwise would be ideal? I read long time back that 2.5 or 3.5 is sufficient, please correct me if i am wrong.

Once this AF is adjusted, the idle screw also needs adjustments? 1300 is ideal i guess.

Drive your bike for about 5 -7 kms in 40 - 50 km speed then adjust the screw between 2.5 - 3.5 turns out (anticlockwise) 360 degree turns / full turns. I think your idle can be in 1200 rpm so that when start the bike after a long rest it will be in 1000 rpm.

While tuning the AF screw check the rpm stability and throttle response.

Im not a mechanical guy. These are out of experience and knowledge gained from the XBHP gurus.

Yeah i know even i am not a techie in this department, but i somehow could not find the AF screw, i see two screws one if lossened drips petrol while the other if lossened it literraly comes out but there isnt any change in the bikes rpm, however, i did keep that screw some 2 turns anticlockwise from its earlier position and now today morning the bike was crossing 60kph quite easily rpm is near 1400 once its warm.

can you post a pic of the carb with both the screws?
it is the second screw that you should be turning... but if you are confused, do post a pic so that we can mark the area for you

+1.Try posting a pic so that its easy to judge.

Hi all ,

I got a solution for mileage.

Yesterday I have tested it with an 100 ML test bottle.

1st I turned the AF screw for 2.5 turns (i.e 5 half turns) from the full tight position

I drained the carb fully until my bike stopped then I filled 100ml petrol in the test bottle and drove in the normal conditions. Where there was a bit of traffic and stopped my bike in signal.

I was driving in all the gears and maintained the speed from 10 - 50 kmph

Then finally my bike started losing the throttle power at 4.5km and started jerking. Then it stopped at 4.9 and after that Im unable to start after that.

Now I turned out the AF screw little anti clockwise. 0.25 turn. I did the same as made for the before test.This time little more traffic and also some roads were bad. And at some places the road was free. In this situation I drove the bike with the same variations between 10 - 50 km.

I lost the throttle power at 6.2 km till that I was able to feel the power when I raise the throttle. After 6.2 there was slight hick ups. My bike stopped finally at 6.6km which is 66 when calculated for 1000ml.

I hope my bike will give at least 50kmpl.If it gives 55kmpl then I wud be happy.

now the AF screw turn is 5.25 half turns.

Things need for my bike are: Shock absorb , New tyres and tube, and need to flush the old engine oil with a engine oil flush and fill it with new engine oil.

Pls suggest me a good shock absorb and tyres and how to do the engine oil flush completely. Is there any thing there to to clean the engine. pls help me.

And I would like to thank PSR jee and other experts who replied and helped me a lot.

So you have understood the way to tune your carb to get what you want....
Good to see your D I Y, and the way you learnt so fast,to do things correctly.
Good Luck to you.

Please see my post no # 6 in this thread for the carb photo..if it is the same, then you have a solution ..also read karthickj's recent post,which will help.

You all need is the patience. Dont be in a hurry. even if it ten times please be patient in testing.

Im sure the company standard turn is between 2.5 - 3.5 full turns / 5 - 7 half turns. If you dont have other problems in carb.

Then it depends on ur bike maintenance that how frequent you do a genuine service.

Check the size of the jet