Meddling with carburettor

Last few days of mine were lost into digging information about Fuel Injection and Carburettor and thankfully with help of some of my friends and netsphere I was able to get a good dose of knowledge.
P200 being a carburetted one I concentrated on carb mostly.As you might be knowing, carb plays a vital role in welfare of your bike's health.A detuned carb can greatly reduce the performance and efficiency.While a neatly adjusted carb can do wonders.
The fact also helps that carbs are much easy to tune/alter than FI.It doesn't need all that electronic gadgetry which FI needs. Once you get to know the basic hardware of carb its easy to do a makeshift operation on it in case anything goes wrong.
In my case the fuel efficiency had gone awry and engine was jerky in 1st and 2nd gear.When I enquired with some, it turned out that carb was set for too rich mixture(which meant it was forcing more than necessary fuel into engine).
Locating the volume control screw is easy.In fact its the only screw on LHS of carb other than the one for setting idle.Besides its bronze color so no mistaking!









As from the pic, I don't need to say the obvious, But will say it nevertheless!
Turning right the carb will channel less fuel and more air making it lean while turning it left will channel more fuel and less air(as in my case).
So adjust it accordingly.
However don't go overboard on either side. Maintaining it on a perfect position is best and will give you right amount of performance coupled with efficiency.
(Remember one thing turning it completely towards right or left doesn't mean peak efficiency or performance respectively) For engine's health you must maintain the balance.
There is one cliche though. Before you embark onto this learn to read your spark-plugs.Don't panic!!Its easy and a must know for enthusiast biker.
Remove both the sparks and check their electrodes for color.
If its more on the brownish side your bike is running on leaner mix if its way too much black your bike is running on rich mix. So ideally it should be dark-brown(almost black but not black!).
When you adjust the volume control ride the bike for a few kilometres and then check for color of the spark plugs tune it accordingly until your bike is running on balanced mix.
One more precaution to take- Don't turn the volume control like you do with normal screws.Do it slowly and only by half or a quarter turn at a time.Its much sensitive.

Update On Fuel Efficiency After some tune-up

Time for quick update, I am in hurry(some of you might be wondering)!As usual I went to Pune last week.Yes it is one place I am always ready to go, superb highway from my town to Pune is one of the reasons.Other reasons follow -
Once there I wound up some unfinished businesses of last 3 tumultuous years of MCA.:)
Then I went to new Probiking authorised service station in Pune.(readers if any from pune - Its on sinhgad road behind IBP petrol pump.name-B.K.Automobiles).I had a prearranged appointment with Mr.Vivek Pendharkar of BK auto.
I had already called him and told him about my bike's falling fuel efficiency and front disc brake that was way too much effective.
So upon reaching there , they quickly went onto business and opened the front disc caliper.Due to rains and my recent trip to konkan had deposited a lot of dirt in it and there was not much lubrication also.
So the calipers were polished with sand-paper and front wheel's axle was greased.
Secondly, carburettor was cleaned and checked for fuel mix.It turned out that the mixture was too rich.Thus channeling much more fuel into engine than necessary.This was the primary reason behind fallen efficiency.
Although I don't know how did it happen.
Anyway it was corrected and also Idle RPM was set.

All said and done, time for real road testing.Here's the cracker - Right after the tuning, bike returned 42kmpl in Pune's horrible traffic.Then I embarked on return journey to home.Believe it or not , on highway at a steady 65kmph she returned astonishing 48Kmpl.

When ridden hard like some occasional bursts to 100kmph or above and steady at 80kmph , it was down to 40kmpl, but still me think it is very very commendable.
Whoever said that performance comes at efficiency's cost, I am sorry, eat your words.

Q & A - My bike's fuel efficiency has dropped suddenly what do I do?

Seems like a pretty stupid question , and I am sorry for making you feel like one but the fact that various people all over face this problem and don't know what to do , lessens it's stupidity.
And another fact that yours truly himself asked this question , puts it into very legitimate terms, ahem!
So here we go.
I asked this very question to people who are in business and know much about such things.
Following is summery of what I got -
possible culprits -

1. The brakes.
2. Tyre pressure.
3. Clogged air filter.
4. Adulterated fuel or filling stations cheating you on quantity.
5. Riding style.
6. Spark plugs with incorrect gaps between electrodes.
7. Carburettor.

A very sedate list?Well thats what experts are, starting with basics and getting them right.
Now I go along the list and check for eliminations , Brakes? No the front disc seems to be in love with caliper :) or is it vice versa? anyway time to get it aligned.
*Tyre pressure? checked Ok and same for Fuel, Spark plugs.
*Air filter looked clean and well soaked.Besides If the air filter icon on dash is to be believed then there is no reason to clean it again. But then again I am not leaving any stones unturned and clean it as directed to me.
*Riding style? well now, time for self check.But considering the fact that my bike is only 2600kms old and me for one is not the type who thrashes his bike like anything puts me(or my riding) into safe perspective.
*Moving onto spark plugs.Opened both of them and checked their color.They showed a very dark brown almost black tinge.Indicating that my bike is running on rich fuel mix than necessary.
But the gap in electrode was perfect, so only cleaned them.
And ahh the fuel! yes there are some filling stations that do sale adulterated fuel and also fill in less fuel than your money is worth.So I filled in petrol from 3-4 places and right now settled on ESSAR.

Time for carb.One of the most important part.This little thing can turn things upside down if not set properly and also gives a very visible change in performance when tuned perfectly.
From my observation of sparks I had come to know that the carb was channeling very rich air-fuel mix into engine and that meant I had to control the fuel mix either by myself or by some mechanic.
As some of you might be remembering that I am far away from ProB showroom. And local mechs are such risky proposition, all this made me do it all by myself albeit with a helping hand from Sandeep and Mr.Venkat shyam of autoservice, Banglore(or bangluru...is that right?)

The whole thing as one can easily make out is vastly general and anyone can use it as a guideline on any bike or vehicle for that matter.
P.S.
**Prior to this the bike was returning about 34 kmpl.
**And now after all the trouble (which seems to have paid-off though) the bike recently returned 39kmpl.




-: Phantom menace.The fear is in the eye of beholder :-

2nd service (and aftermath)

I had planned for a 1 day return trip which was of about 400kms.(Check that ride here).
So I thought of getting the 2nd service done before going onto the venture.
The bike was running fine actually but neverless got it serviced at something like 1890 kms.Took my bike to ProB and thankfully thay delievered it within 2 hours.
Although the manual doesn't say to change the oil, it was done.One good news - Pune ProBiking now fills 'Motul 3000t ' as standard oil at no extra cost.This oil, I was told is very popular amongst enthusiasts, but due to its non-availalbility I never had chance to fill it in my bike ever.
While I write this the bike has run 2533kms.

Coming back to point, This is what the mechanic did in front of me-

1.Opened the drain nut and drained all the oil.
2.Cleaned the air-filter.
3.Checked tyre pressure and both the brakes.
4.I had told him about hard gear shifts, so he loosened and then again tightned the clutch cable...thats all.
5.Checked the battery,lights,indicators and horns.
6.Lubricated the chain.
7.Filled in the oil and washed the bike.
Done!
And I paid Rs.260 for this...anyway,

The changes I noticed after 2nd service-
1. The engine is now infintely more smooth.Overall sound output has reduced considerably.The gruffness that you feel in new bike is fully gone.
2.The gear shift which was edgy and rough (especially 1st -> 2nd and vice versa)to my choice is more or less same.
3.Throttle response has sharpened.or is it the smoothness that's fooling me?But its welcome anyway.
4.Sadly and amazingly, Fuel efficiency has gradually dropped since then.To be frank I was expecting a rise. Previously I was getting efficiency in the region of 45kmpl.Which has now come down to 38-40kmpl!
How did this happen is beyond me.Next time I go to pune, will surely go to ProB and consult them. I suspect some screw setting in carb has gone awry or is it the spark plug or is it the air filter or is it..... :)
5.Fuel gauge that was faulty from day one is still faulty.The sensors are out of stock(still).Bajaj please do something!
6.I heard Starter motors were being replaced in all P200s.Again those starters were out of stock, no luck here also! In any case my starter is working perfect so no gripes about it.

And yes the ProB people are not that great at washing the bike.May be rush and very narrow space there freaks them out!
All in all its mixed bag of things after 2nd service.Smoothness is welcome but at fuel efficiency's cost?No sir I am not game for it.
OK!Now drool -