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Originally posted by psr View Post
I'm aware of Pacco India!!! I was asking how does the
looks likebleed screw for bleeding out the bowl petrol along with dust accumulated in bowlSkill is what keeps you on a Motorcycle
Awareness + Skill is what keeps you out of harm's way
ATGATT + Awareness + Skill means you might Live To Ride another day
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This weekend I'd a very weird situation. I was trying to tune the carb & during that process, I'd tightened the airscrew to max. Then all of a sudden the vehicle started revving at high RPM & when I switched off the keys, nothing stopped, it still kept revving at high RPM & the carb was doing its job beautifully.
What happened here? I assumed that, the suction pulled the AF mixture from the carb indefinetly. But on turning off the key, the CDI should've stopped doing its job, but it didn't. What am I missing here?
Any thoughts on this is highly appreciated.Skill is what keeps you on a Motorcycle
Awareness + Skill is what keeps you out of harm's way
ATGATT + Awareness + Skill means you might Live To Ride another day
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It is called pre-ignition and happens when the AFR is lean and the engine is hot,and if the compression is way higher than normal.You should check your Spark plug's heat range also. A stock engine will never face this problem...you may post the alterations if any,you have done which might give a clue and possible solution....but judging by your say, it seems to be lean AFR(air screw tightened fully) and or ,plug heat range being hot.Originally posted by aargee View PostThis weekend I'd a very weird situation. I was trying to tune the carb & during that process, I'd tightened the airscrew to max. Then all of a sudden the vehicle started revving at high RPM & when I switched off the keys, nothing stopped, it still kept revving at high RPM & the carb was doing its job beautifully.
What happened here? I assumed that, the suction pulled the AF mixture from the carb indefinetly. But on turning off the key, the CDI should've stopped doing its job, but it didn't. What am I missing here?
Any thoughts on this is highly appreciated.
When Was The Last Time,You Did Something For The First Time.
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Is itOriginally posted by psr View PostIt is called pre-ignition...heat range being hot.
? But PSR ji, it happened only by playing with IDLE screw not with air screw. I tightened it to the extreme & once released, things became normal. Color of plug was tard black.
Skill is what keeps you on a Motorcycle
Awareness + Skill is what keeps you out of harm's way
ATGATT + Awareness + Skill means you might Live To Ride another day
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Originally posted by aargee View PostI was trying to tune the carb & during that process, I'd tightened the airscrew to max. Then all of a sudden the vehicle started revving at high RPMWhich of your post is correct ? I made my observation based on your earlier post....#82Originally posted by aargee View PostIs it
? But PSR ji, it happened only by playing with IDLE screw not with air screw. I tightened it to the extreme & once released, things became normal. Color of plug was tard black.
If your later post is true,then the reasons for increased RPM even with throttle closed are:
1. Your throttle slide got stuck .
2. your throttle cable is not free and should be lubricated.Last edited by psr; 02-14-2011, 12:06 PM.When Was The Last Time,You Did Something For The First Time.
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Its the IDLE screw, not the airscrew. Sry about the miscommunication ji!!!
Throttle, cable including screws are new & well lubricated in this case.
Something seriously wrong with me :banghead:Skill is what keeps you on a Motorcycle
Awareness + Skill is what keeps you out of harm's way
ATGATT + Awareness + Skill means you might Live To Ride another day
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Take a break get some restOriginally posted by aargee View PostIts the IDLE screw, not the airscrew. Sry about the miscommunication ji!!!
Throttle, cable including screws are new & well lubricated in this case.
Something seriously wrong with me :banghead:
.
When Was The Last Time,You Did Something For The First Time.
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I'm under the impression that the round/flat slide needle controls the flow of AF mixture during the idle. Is my assumption right or incorrect?
Problem - I've a heavy flutter (along with jerks) after certain rev (which I'm unable to say the RPM due to lack of RPM meter) especially when the throttle is closed. So after a lot of adjustments, I placed the pin lock to the top most, trying to make the AF mixture leanest during idle. There was some success that the flutter has come down considerably along with jerk that is much better than before. What I expected was a hum when the throttle is closed, which I'm unable to obtain till date. The carb I'm using is VM22.
So I got a new needle y'day & unfortunately it was smaller (of VM20s). This means, the top most point of VM20's is the second position of VM22. So I positioned the new needle (VM20) to top most position thinking what bid deal, just that the AF mixture would get richer. But I was wrong.
This morning, the vehicle behaved as if its starving for air or fuel or even both & I was really surprised as why this is happening. Switching ON choke seems to be easing out.
Appreciate if anyone could point me what went wrong with my assumption or actually what is going on inside the carb. Tks.Skill is what keeps you on a Motorcycle
Awareness + Skill is what keeps you out of harm's way
ATGATT + Awareness + Skill means you might Live To Ride another day
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answers in boldOriginally posted by aargee View PostI'm under the impression that the round/flat slide needle controls the flow of AF mixture during the idle. Is my assumption right or incorrect?
The needle controls AFR, but after 2,000 RPM.
So I got a new needle y'day & unfortunately it was smaller (of VM20s). This means, the top most point of VM20's is the second position of VM22. So I positioned the new needle (VM20) to top most position thinking what bid deal, just that the AF mixture would get richer. But I was wrong.
This morning, the vehicle behaved as if its starving for air or fuel or even both & I was really surprised as why this is happening. Switching ON choke seems to be easing out.
You can't put a 20's needle in 22. They have different Taper profiles,and it will cause the needle to be slanted in the emulsion tube and when you raise throttle it will be dancing inside the tube to give varying Mix each time. The emulsion tube and Needle come as a Matched set , and should be used as a matched unit...
Appreciate if anyone could point me what went wrong with my assumption or actually what is going on inside the carb. Tks.When Was The Last Time,You Did Something For The First Time.
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Makes a perfect sense & no wonder I couldn't think in these lines
I understood my mistake. I'll go get a VM22's needle. But on the other hand, what happens when I try using bigger needle? I know I cannot use the top or may be even 2nd from top's position, but still, just want to understand. Any insight is appreciated. Tks.
Skill is what keeps you on a Motorcycle
Awareness + Skill is what keeps you out of harm's way
ATGATT + Awareness + Skill means you might Live To Ride another day
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