Originally posted by ashwinprakas View Post

Cool bro, wasnt supporting the theory that everything can be done with the help of a screwdriver. Was pointing out the ignorance which is commonly prevails, if a rep of a reputed company says like this then you can imagine the plight of the common people sitting at the place where you do polution checks. They retune carb without any detailed knowledge on the same.

At the same time it is true that some dedicated experts are there who actually is helpful to other bikers.
By the way, none of the pollution checking centers is tuning carburetors. What they are doing is analyzing the exhaust gases and giving the result as a certificate.
Previously it was easy to tamper the result but it is not easy now as the test procedure is computerized.

Originally posted by Pinaki View Post

Carburetors have adjustment screws , how else to manipulate those other than using screwdrivers ?

What is the need of this manipulation? If it is to retune it, there are other correct methods.

Originally posted by Pinaki View Post

I am sure that even the factory uses screwdrivers to accomplish this . Yes the factory doesn't have time to tune each carb individually by riding each vehicle , they have a test bench where carbs are tuned optimally before fitting . I say "optimally" because carburetors don't have one single exact precision tune that is the best , they have a range of good tune

Originally posted by Pinaki View Post

ASCs use handheld rpm meter only other than a screwdriver . Gas emission testing is not done for tuning the carb generally , unless a PUC is also asked for .

Originally posted by Pinaki View Post

I have seen many mechanics have this experience and are able to do it correctly without rpm-meters too .

How can we say they are doing it correctly, especially when their tuning is not rechecked? And please remember, most of the bike manufacturers are not selling out spare parts because of these mischievous local mechanics.

Originally posted by Pinaki View Post

If someone is able to reach the same position of two screws without using an rpm-meter (or gas analysis) that I can reach only with such equipment , I have no objection to it .

Originally posted by Pinaki View Post

Sorry , I wasn't aware of previous debate and strong feelings about this .

There was nothing like that. More than that, we, Ashwin and me, are good friends even if he does not agree with me.

Originally posted by Pinaki View Post

Yah , I that's what I do now, let the head-mechanic at my ASC do it .. he uses a handheld meter & screwdriver for this .

Please go to any Suzuki authorized SC and see how they are tuning the carburetor.

Originally posted by Pinaki View Post

But I also don't think it would be difficult for an end-user to learn up either and what other way to learn swimming unless you get into the water ? Yes, going at it without knowing what you are doing can cause some trouble , but isn't that with everything ?

You have the absolute right to swim and drown but asking others to follow you is a crime under CrPC and, perhaps, CPC.
And why are you not riding through the rail track to understand how the hitting of a train is?

Originally posted by Pinaki View Post

I have already made a few attempts at it , reaching at very good tune a few times too .

As I said earlier, you landed on your feet instead of a possible landing on nose.

Originally posted by Pinaki View Post

I don't think that you can cause any damage to the engine trying to tune the carburetor , unless you have no clue to what you are doing at all . At most , my bike didn't run as well as I'd wished it to until I got it corrected . That's it .

But mine and most others GSs are going fine and any roadside carburetor tuning is absolutely unnecessary and that is why I am opposing it. It is not for any personal gain.
And thanks for making this thread active again. Most of the GS owners are sleeping continuously for weeks.

They are all not sleeping but watching the performance of the Always active dark Knight (aka Punarvasu)

as you are their we are simply reading the thread periodically; moreover with a trouble free bike we have nothing else to type or complaint.

would blame GS for its characteristic behavior of making the owner sleepy and happy

+1

Sent from my HTC One X using Tapatalk 2

While it's nice to try setting it myself, I believe a brief test ride after each attempt is required to test the state of tune. This is more of a problem than reaching for a screwdriver. Trial and error requires persistant effort(~time) and observation(~energy) for subtle changes which from my current position is a luxury.

But I agree to your view that there's no better way to learn swimming than taking the plunge.

idle speed adjustment screw. Picture in page 6-24 of owner's manual.
*Second one is idle circuit fuel adjustment screw.

You can close the idle circuit fuel adjustment screw by screwing it to the last thread and the engine will still start and run as long as the throttle is opened. You can even adjust the idle speed by rotating idle speed adjustment screwidle speed adjustment screwidle circuit fuel adjustment screw. To do that, when the engine becomes cold, start the engine and adjust the idling by rotating (opening) the idle circuit fuel adjustment screw. Set the RPM to, say 1100 or to a similar value (all GS owners know that our bikes will be idling at 1100-1200 RPM when the engine is cold ). When the the engine heats up and start to run at normal operating temperature, do the following.

*If the engine is idling at very low RPM even after the engine is heated to its normal working temperature, open idle circuit fuel adjustment screw and set RPM to 1300-1500 RPM

*Always remember whenever the engine refuses to drop to its normal idling RPM smoothly you will always have to adjust idle speed adjustment screw (Anticlockwise).

*If the RPM drops suddenly while shifting the gears as mentioned in the problem no 2, you will have to open idle speed adjustment screw (Clockwise). Try to rotate the screw at the rate of 45 degrees or less at a time. The resulting increase in the idling RPM should be reduced by adjusting idle circuit fuel adjustment screw

I always feel the need to learn things about my bikes and how they tick or why they sometimes have trouble running as well as I want then to . For this, I am open to new ideas from all here , and am not afraid to make mistakes on the way . For I know not of any other way to learn than to make mistakes , and share our knowledge .. however little I may have or other's may provide .. collectively it's a great knowledge-base . Neither am I afraid to break my machine , or the warranty - if need be .. to see if can be bettered in some way . And I have always happily found out that it can be . And I always have and shall encourage others to learn in this way too . You or anyone else reading these forums are however free to conserve their energy, and their machines and stick strictly to the maker's manuals .... it's your bike and no one can force you to dismantle carburetors or such and so forth . We all know this , but we still come giving advice and opinions , sometimes very faltu ones like mine ... in the faint hope that someday it may benefit a fellow biker in some distant way or we may all learn from my silly mistakes . The disclaimer , that you try any of it at your own peril , although not always mentioned , is always present and implied .
As far as the owner's manuals are concerned , I usually refer to them when they may be of assistance in messing something up further than I could manage all by myself .
Just a different way of thinking than yours ... not a claim to any expertise or ultimate knowledge in any way .

The BS26 mikuni/UCAL is not very complicated to dismantle or service .. I have completely dismantled the one on my best friend's kawasaki wind-125 (which was UCAL BS26-176 I think) cleaned and serviced and reassembled it twice already with common tools I have here . Later the AFR/idle/throttle-slack had to be fine-tuned a bit at the Bajaj ASC , from my rudimentary tuning post-service - took them all of 5 mins . It is working like new now( that friend says that, at least much better than it was earlier, I think ) . No problems .

Yes you are right , as is with most trial and error methods .. it took me lots of tries and mistakes and swearing and time . First time around , a month I think , filling just a liter a petrol everytime I hit reserve(then noting down the odometer on phone) to just check the fuel-mileage obtained every-time too ... other than running smoothly . But in the end , I got it running exactly as I wanted . Also by that time I had a very good idea about a starting point ,where to begin - should I need to start from scratch again on that particular bike .

I think think the factory sets the carb for an average good tune at their test bench (just right to pass the emission norms and run reasonably well) for all places . They don't fine tune it for altitude differences etc between bikes sold in kashmir or chennai or rajasthan , for example . Of course I have never actually seen how they do it - it's all my guess . One thing I am certain about is they haven't fine tuned for my liking or riding habits or the quality of fuel I get etc etc too . My other feelings is that carburation varies from season to season , and doesn't work the same way in monsoon as it does in summer or winter either . I have also found the need to retune a bit when I shifted from 10w30 to 20w40 oil , or put in a new type of plug(G-Power) from the OE one let alone when I needed a bit more juice at top-end .... these are of course just what I felt while riding , only someone who understands carburetors well can say if these are accurate observations or not .

In my case when i shifted from Castrol Activ to Power1 the idling rpm decreased to some extent, but kept the carb. in previous settings. The engine
felt more revvy after changing to power one. My normal cruising speed increased by at least 15km/h because it felt more tempting to revv the engine.

My bike is running well without water wash ie.8th paid service for the past 4k+ kms.. Yet to finish the 8th service...

Today on my way to work, just checked in my service center ABT to adjust the chain slack and got to know that Suzuki Japan is doing Auditing at the service center..

Glad to hear that top level management is taking care of the quality at the service centers.....

Good to hear but I hope they try to ask for customer feedback as well.


@dip097- Doesn't closing the idle circuit screw mean that we are trying to cut off the fuel supply?


Also, my SVC charged Rs.700 for paid service with oil and oil filter change. I have a feeling this is more than other Centers. Please confirm.

Closing idle circuit fuel adjustment screw will cut off fuel supply through the idling circuit. But we could run and idle the engine by adjusting idle speed adjusting screw, which basically adjusts the throttle valve.

I too wished the same.,

Price should be the same in other centers for a 150cc bikes..

Bcos Oil Price is same, filter price must be in range, labour price will also be the same...

Nice ... i will save it , its not risky to tune up carburetors in this generation of bikes as tolorences are wider ( i think its for environmental norms ), previously( 8/10 yrs back) exhaust note used to sound differently at each micro turn. still this (AFR screw)should not be adjusted by un experieced person

+ 1 , this is still most active thread

I aggree , AFR should differ as per climate , altitude, riding conditions , seasons though not mandatory
I wonder how eco - power mode (in our GS offcourse) have to do with fuel supplies though in previous threads this has been discussed and concluded as only for indicator purpose . SC guys claim some electronic control in A/F ratio when selecting modes.

Hey buddy..post some photos of the carb of GS and label the parts..it will be good education.

Although I am against fidleling with the carb without any knowledge..its always good to know how the things work in it..