ESC or battery problem?

[Kelk]

Hi all,

Hope you can help - my YZ-2 feels like it's lacking "push" - it feels laggy if anything compared to what I asked it to do via the transmitter. Steering is absolutely fine.

Tx- Sanwa M12 so defo fast enough
RX - Sanwa for M12 (at work so can't remember number)
ESC - Orion R10 - punch set at 8, boost at 10, turbo on
Lipos - Orion 4500 carbon looking ones shorty's

Whenever I'm getting back on the throttle the car just doesn't seem to pick up and go compared to others. I'm on a 22T pinion for a standard spur gear. Also find that my fastest lap is usually one of the first 3 in qualifying by about 1 second over a c. 20s lap.

So I wonder if it's the cells are getting to the stage of being worn out as they are well over a year old and been used very regularly. The esc is slightly older than a year and likewise gets some good use. I have checked to see if the capacitors "smell" at all in case of burn out. Nothing.

Any help before I find myself replacing the esc and the cells all at once which is obviously a pricey way to fix it by buying it all new.

Thanks