You never mentioned the TPS at all in all of that (Throttle Position Sensor).
A bad TPS can cause difficulty starting, poor/rough running at low speeds and generally makes the bike feel like shit.
Located on the right side of the carbs, with the covered wire that plugs into it. It should be checked before and after a carb balance.
The TPS outer case unplugs, it's a bit fiddly, i normally gently use a flat key to unhook it.
With key in ignition switch it on (don't start engine).
Unplug the TPS
The rev counter needle should go to 3000rpm.
Then plug it back in and the needle, if positioned correctly, should land on the 5000rpm mark.
If it goes to 0rpm or 10,000rpm it needs adjusting back to 5000rpm.
If it goes back to 3000rpm it's totally knackered.
To adjust it, the 2 screws need slackening with a security torx allen key, then rotate the TPS unit until it lands on the 5000rpm spot.
Be aware, these units can slowly break down rather than just stop working so can misbehave for a while until you realize it needs replacing.
There are more detailed explanations on here so have a good look about as i'm about to head off to work now.
Note: DO NOT BUY A USED ONE if it is faulty. You have been warned!
https://www.ebay.co.uk/itm/YAMAHA-FZS-60...SwRytb6JaY
A bad TPS can cause difficulty starting, poor/rough running at low speeds and generally makes the bike feel like shit.
Located on the right side of the carbs, with the covered wire that plugs into it. It should be checked before and after a carb balance.
The TPS outer case unplugs, it's a bit fiddly, i normally gently use a flat key to unhook it.
With key in ignition switch it on (don't start engine).
Unplug the TPS
The rev counter needle should go to 3000rpm.
Then plug it back in and the needle, if positioned correctly, should land on the 5000rpm mark.
If it goes to 0rpm or 10,000rpm it needs adjusting back to 5000rpm.
If it goes back to 3000rpm it's totally knackered.
To adjust it, the 2 screws need slackening with a security torx allen key, then rotate the TPS unit until it lands on the 5000rpm spot.
Be aware, these units can slowly break down rather than just stop working so can misbehave for a while until you realize it needs replacing.
There are more detailed explanations on here so have a good look about as i'm about to head off to work now.
Note: DO NOT BUY A USED ONE if it is faulty. You have been warned!
https://www.ebay.co.uk/itm/YAMAHA-FZS-60...SwRytb6JaY
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