Cylinders 3 and 4 (right) cooler than left ones

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pikipikos

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Hi guys.. Hope that you are all ok with this shitty Covid19 situation! Hope it passes soon!
What's the reason for right cylinders to be almost half temp low than leftys?
I checked with IR thermo..
I am going to take apart the carbs clean them and sync them.
But i am thinking of changing the coils of cylinders 3 and 4.. To see if the combustion improves.. Is it anything else or this usually happens due to bad dirty carbs?
How does HV coil affects proper full compustion of the mixture and how i tell?
Pikipikos waiting for reply.
 
Sounds like the carbs may need a sync or a/f mix screws adjusted.
 
If they aren't firing at low speed due to clogged jets, or a bad synch/air bleed screw adjustment, those pipes will run cool, and once the revs are where the main jet is feeding the fuel, and it ignites, then the pipe(s) warm-up. If two cylinders aren't firing evenly at low revs, it will sound like crap. In other words 'what Sean said,' and a bit more.
 
Well ok, i am about to do the carb cleanup.
One more thing guys:
I read a threat about the pickup coil problems. This is related to the ignition timing right? If it was the pickup coil, should that affect the combustion, sparks and inapropriate burn of the fuel mixture?
What about the HV coils? If the readings (ohms) seem as manual says, shall i keep them or chage at least the right ones (cyl 3,4).
Pikipikos
 
Pick-up coils tend to either work or they don't or work when cold and fail when hot so no, that isn't your problem.

Do they come up to a similar temperature when at (say) 3000 revs?
If so them most likely an idle circuit issue.

Start with the basics (carb synch) before you do anything else. We often overthink the problem and ignore the simple things.
If that doesn't help move on to the pilot circuit.
If the tamper proof plugs are still in place they will need to be removed.
The idle mixture screws are set at the factory so make a note of the settings as you remove them.
NB: Ensure that your screwdriver is a good fit! If it is sloppy or too small there is a risk that you will strip the head.
If the tamper proof plugs are out then sat at 2 1/2 turns out once you have cleaned it. Look at 'The Shotgun' which shows how this can be done.
 
Thanks Maxmidnight. i am waiting some carb parts and i will start the carb stripout , cleaning and tuning
Hope it goes well.i will let you know. So as you said: 2.5 turns out(i will put new pilot screws -the ones i have now are stuck. ) neddle clip on the third?
Also , i have new brass plugs(tamper)..shall i fit them or leave the mixture screws to make adjustments and put some rubber plugs instead, to remove easy??
 
No-need to replace the plugs. Maybe if you enter a concours.

"Stuck" pilot jet screws? Try a bit of heat. Make sure that your screwdriver is as-large as it can-be, to fit the slot on the pilot jet. Nothing the matter with cleaning a pilot jet, though having them on-hand to replace is always a good back-up plan. Save the old ones. I usually use a pin vise and a small bit of stainless steel wire to poke-through any stubborn deposits in the pilot jet that aren't removed by a soak in cleaner/solvent, and an air-hose.
 
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