Re: The Honda CB Twister

from the pics you posted, this is a different carburetor from that on Twister. it could be a kehin PB model...but surely not the same model as on twister. your arrow markings of AFR and idle screw are correct....but i cant make out if AFR screw is a fuel screw or air screw. point to note here is that both AFR and idle screws are located on same side and very close to each other.
@Pinaki, does hero passion X pro has this type carb?

Re: The Honda CB Twister

Umm yah , it isn't the same keihin-pb that is on my splendor either . On mine the AFR screw is on the other side .

Re: The Honda CB Twister

@all- To clear your confusion let me tell you that almost all PB series carburettors have air screws and CV series have fuel screws. So twister has a PB series which is air screw.

Splendor and Twister both use PB series carb but the difference is that splendor series use 18 mm venturi while twister series uses 16 mm venturi similar to pleasure and Activa.

Black smoke on warming up indicates that engine is burning excess fuel as compared to air which is giving out black smoke. And tuning is not leaning or richening the mixture but setting it perfect.

So to tune the bike follow this procedure:-

1. Warm the engine properly,
2. Increase the idle by turning the idle screw so that bike idles approx around 3k rpm(just approx by hearing sound).
3. Now fully tighten the screw(lightly as too tight and carb thread will go).
4, Now slowly open the air screw by 1/16 th of a turn.
5. Go on opening till you get highest idling. After the point where you get highest idling if you open more idle will decrease. So once again turn it in opposite direction. At the point where you get highest idling stop turning air screw.
6. Now decrease the idle from idle screw until engine gets into a steady idle (around 1000 rpm by sound).

First time you may feel awkward but with experience you will feel good. I can adjust air screw even without raising the rpm. This is the correct method of tuning the mixture of bike.

As for the spark plug photos then the correct mixture setting is this:-


This is my Joy plug. and you see the electrode is reddish brown like brick. This is the correct setting. Even after i have tuned my extreme, plug color is like this only.

Re: The Honda CB Twister

From yesterday onwards my bike goes off shortly after starting,with a faint tic-tic sound.Please help me out.

Re: The Honda CB Twister


Well I havent seen spark plug with this color till now !! I can see great love for your machines in your posts...Its great to have people like you in this forum.

Re: The Honda CB Twister

Thanks for the explanation Sibun, i havent seen such a colored spark plug either
On my DY bike i dont see the black smoke issue if i turn the AFR screw anticlockwise by 1/8th turn and it makes sense if the screw is Air screw ( turning it towards leaner mixture from a rich setting)
I will run this week with this setting to see the impact on mileage and post back here

OT, I liked your thread on Joy, amazing to see a bike so well maintained which has completed >3lakh kms

Re: The Honda CB Twister


You have not seen this spark plug as you have never seen a perfectly tuned carburetor. Open an FI bike plug like ZMR, and you will see the plug of same color. Usually white tends to be leaner and black toward richer. Brick red is the color to go. My mechanic taught me to tune the bikes and my mechanic is one of the expert tuners that i have ever met.

And thank you for the complement on my Joy, actually it is not a bike but part of my life and regarding it being so well maintained then i have done anything special. Its just that it is so maintenance free that i have not done anything special.It is so much maintenance free that even my new extreme feels like it is demanding more maintenance.

Re: The Honda CB Twister

there could be spark leakage at spark plug cap. this happens mostly when it raining...or when bike is wet. the spark plug caps provided by honda are not of good quality....i have already replaced it twice. first remove the spark pulg cap and clean it with dry cloth....remove any water/moisture that may have formed in cap. also clean the cap for any carbon....and put back. it should run ok.

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hey rajaselvam, plz post a pic of your bike with pulser shocks!!
[MENTION=60369]smartrider[/MENTION], this is my old spark cap.

Re: The Honda CB Twister

Thanks buddy. Can you mention the symptoms of wet spark plug cap,because I reported this issue during service but those dumb guys said its a fault of the self start & worked on it.They assured me that the problems were rectified & returned the bike .But after service the ride only got worse.

Re: The Honda CB Twister

Symptom is the motor dying unpredictably without any other obvious problems , particularly when the bike is got wet for sometime like after washing or an hour in the rain . If you can measure it with an ordinary multimeter , the correct resistance value of the plug cap should be around 4 - 5kΩ . More is bad .

Re: The Honda CB Twister

symptoms like small tik tik sound coming from spark plug and engine dies while trying to raise the throttle from standstill. you may also see small spark coming out from plug cap.... for this you need to observe plug area at night i.e under complete darkness.
basically this is a problem of low insulation resistance...as pinaki said.

Re: The Honda CB Twister

Yes buddy,as you said,there's spark leakage.I felt a shock over the plug cap.I see a brownish wire tip inside the cap.Is that normal.I think,the wire has corroded.Please suggest a way out of this.

Re: The Honda CB Twister

Brownish means rust . The plug-cap is a goner . Buy a new one .
Twisters plug cap is of same make as splendor's ( ANU ) so cost should be around same too ( ₹90 ) . I've had the same problem with mine - http://www.xbhp.com/talkies/motorcyc...tml#post917077 . If you are interested to know , later I had dissected the dead plug-cap and this is what I found - http://www.xbhp.com/talkies/motorcyc...tml#post918585

There also lots of valuable inputs about spark plugs and plug caps inbetween these two posts from more experienced members . Read it , I learned a lot from it .

Re: The Honda CB Twister

way out is to replace the plug with new one....you can buy a new plug cap from Honda spares counter for around Rs 70....and get it fitted from any roadside mechanic. The tip inside new plug is normally of golden yellow color(this is the place where spark plug fits in)...and due to faults like sparking, the color of this tip starts fading...and becomes blackish...due to carbon...thus obstructs the flow of current to spark plug. The other end of plug cap is the threaded screw like tip where the wire from ignition coil is connected. This is the place where corrosion takes place. mechanic usually cleans the corroded tip before fitting the plug. ----consecutive posts auto-merged----- well now i get the clear picture of whats inside the plug cap. i had earlier opened the plug cap and found a spring and resister.....but could not understand that its the" resister"......i thought it must be some kind of "Fuse"(because of its shape). another thing is that plug would get very hot during normal running....i could not touch it for more then a second. below pic of my old plug shows resistance of 4.66 k ohms....seems just within limit. what is purpose of these resisters....just to prevent radio interferences?.... any bad effects on engine or electricals if i use plug cap without resisters?

Re: The Honda CB Twister

It's a ceramic resistor of less-than 5kΩ . It's there by govt. rule to supress radio interference only . No benefit to the bike itself . Problem is there is another resisitor of same 5kΩ value inside your spark plug itself . So resistance + resistance in series adds up and weakens the sparking current . You can easily eleiminate one of these and my bike is running much better like this . I am running a local made non-resistor plug cap with OE plug . Shoeb is running a OE resistored plug-cap with a non-resisitor spark plug ( mico U4A ) , so in effect the same thing . Or you can try a OE pulsar plug cap ( which is incidentaly very cheap and much better made too ) , it's having a low resistance value of 1kΩ only . No bad effect on engine possible from better ignition I think .