Unlike what was said, the needle for the main carb of the XT 600 E does fit that of the TT 600 RE. I ordered a kit from Aliexpress advised by someone that has a TT 600 R and the needle fits perfectly, just so anyone who's interested knows. The bike has actually more power on low and mid ranges, behaving better than before. No need to spend 10x more for an original part. I'm now trying to address one last issue which the bike already had before the needle broke. In 3rd, 4th and 5th gears (maybe in all gears, but I notice it in these three), when I open the throttle to the max (from 4/5 till fully open), the bike stutters and doesn't keep on reving/rpm drops a bit. As soon as I go back to 4/5 throttle, it starts revving up again. Any idea about what might be causing this? I've read about (and will try) taking the air filter out and checking if it improves, disconnecting the sidestand switch, buying a new slider/diaphragm for the secondary carb. As always, thank you very much in advance!!