Depends ,buddy.Since it's known that it happens when the battery is low,but if your battery's fine ,then it can only mean that the engine is struggling and it's reflected on the tacho.How's the performance in relation to the throttle input?and i hope that the clutch's fine.

Welcome buddy .Maybe you should try uploading the pic's of your girl once more.

When was the last time you lubed the Tacho cable

Can be a battery issue, or a regulator issue, the regulator may have been conked off.
try blowing your horn when the needle starts dancing.

Clutch plates&cable are good. The engine is performing as usual, only that the tacho is showing wrongly.

Do you mean accelarator cable?

Yes, I have a doubt on the regulator. Earlier the horn used to sound weird when the throttle was open, but now it sounds fine after horn tuning.
I need to get all the electricals checked at an auto electrician, the wet stalling issue is also irritating-don't wanna be stuck in the next rainy season!
So what about the switches-have you got them installed?

Yes . If the RR is defective, or if the tacho has some iron dust inside sticking to the magnet then also it can happen.First get the Tacho opened and cleaned ,then check the RR out put without battery...if the voltage keeps swinging erratically at idle, suspect RR unit.

@ psr

Why is it needed to remove the battery and then check ?
we can keep the battery and check weather the terminals are showing more than 14.5v across the rev range, if yes then the regulator is conked off.

@ sarvajit

I gave my switches to the mech yesterday, haven't got them installed yet.
i don't know anymore about the fiero handle, as i am using FZ one.
all the mech said that we'll need to drill a hole in the handle to accommodate the switch lock, as its on the base and we can't break that lock (as i did with fiero switch lock which was made of plastic) as these locks are made of metal.
I think fiero lock is at the base itself so it won't even need drilling. (others please confirm)

and yes, 1 more thing, that only the RH switches have that outer end bigger and inner end smaller, the LH one has same size dia on both the ends.

and the great news is, INSIDE that bigger dia hole, there's a smaller dia hole too (5-10 mm away)
which means it will snug fit definitely.

Sorry for the delay buddy, my bike has a lot of work to do and the mech is very busy with many more bikes....
he barely has time to work on my bike, i am still finding some last list of parts, once i get them all, i might finish the work in a day...

The definite thing is, that they are analogue types, and they will fit.
regarding the choke, i forgot to ask my mech when i met him yesterday, weather it will fit directly on the carb, but i strongly feel that it will.
I'll ask him tomorrow for sure.

Meanwhile our very own technical intelligence a.k.a Gixxer and PSR can highlight the same....

Answers in Bold

So do you mean I should take it to a meter repair shop as well as auto electrician?

Thanks, I am keeping aside the switches thing till Nano figures out the mounting as well as carb jugaad.
I would have gone to an auto electrician this weekend, but I need to get my R15's radiator coolant leakage sorted out.

@NANOtech

All these electrical things can be done ,provided the mech is good and the soldering etc can be done at a auto electrician.Which i am sure you know better than me.Regarding the carb,it can be done too ,but my question is what's the need of choke?.Why not simplify things further and leave it out completely,because from my experience and from what i've seen older model bikes run richer due to relaxed emission norms.I've never used it since the first couple of weeks after purchasing the bike and it's the same with others too.

Sarvajit,disconnect the choke buddy.

Today i was at the welding work guy and he had a fiero bend pipe ,an wider one that is ,without any chrome coating etc.The bu@@er is asking 800 Rs for installing it onto the bike's silencer.Which according to me is too damn much.It's just a iron pipe matched to that of the fiero.

Sorry gixxer_junkie I'm unable to upload the pic, So I've given the pic's URL link.

By just observing from the outside the engine/gearbox in the Fiero family and the Apache family of bikes looks very identical. How much does the engines differ on the inside...I mean power, torque, comp ratio etc...

Also what is that rod on the side of the engine(near the sparkplug)? I read in an very old review of Autocar mag that its an 'External Oil Pipe'...Is that true?. If yes why is that needed?

The Apache Engine/Gearbox:-

I asked sarvajit to disconnect it long back, but he seems to be wanting to keep it.
i NEVER used choke ever, apart from the times i pulled it to check weather the cable is jammed up or not.
i always needed to change the cable as it used to jam up pretty hard and break on pulling.

Besides, i don't think any soldering will be needed to install the switches too.
a standard connector is provided, we'll need to just check which wire does what.
These maybe tricky as the back-light thing exists, and i want the back-light to be always ON, if it doesn't have a dedicated ON connection i.e if it taps the current from the pilot lamp wire, only then I'll keep them off normally.

they are minda made, so i assume even our switches are the same, so even the connector may have the same plug points.

Besides, i forgot to mention that my head returned back from the lathe guy yesterday, it has a 0.5mm dip than the stock couldn't do more as the valve seat area was just 0.1mm away, and the edges were smoothened, the squish area was grinded too, very smooth to avoid any sharp edges, i hope it all works well when installed, i think I'll try with just 1 gasket below the bore first...

That's good to hear.Coming to gasket,yes install only one ,because due to head widening there will be a drop in compression ,meaning drop in power all over the rev range.So don't go for 2 gaskets,if done it will reduce top-end even further.
If the porting work's done properly,it should to some extent improve things.

My bike has high compression despite widened engine head and that's because it's a modified ZMA piston.Were as your bike has a standard RTR piston,so don't go for increasing the gasket numbers or that of the packing.

The additional Gasket under the bore was only to offset your not matching the head to the bore dia, and the resultant high compression..Now that you have matched it,Like Gixxer said no need for additional Gaskets.