Greetings community! I´m sorry for my bad English.
I have a Kymco Downtown 125 € 4 from 2017, which for a few days has had a problem, and that is that when I slow down to stop, the motorcycle idle (without transmission load), it stays slightly accelerated. That is, when I stop, the bike stays at 2200 RPM's and then progressively drops to 1800, which is its idle. I didn't do it before, so i have made the following checks:
1. Valve adjustment.
2. Check the throttle cable to see if it was stuck in any section of the sheath. Negative result.
3. Check the throttle body spring travel. I have lubricated it lightly with Oil 3 & 1 with the same result. It slides much better than before and the end of the race can be felt strongly.
4. I have reset the TPS and ELP sensors according to the motorcycle workshop manual.
5. I have cleaned the lambda probe with ultrasound. It has been quite good and has released charcoal.
6. I have loosened the engine drive belt and tested the engine idle (no load) and it does the same, it stays accelerated and progressively lowers to idle. The purpose of this is to rule out problems with the variator or with the clutch or pulleys.
The only thing left to do is disassemble the throttle body to see if it has any kind of dirt in the ducts or in the potentiometer.
Say that the filter you have right now is the 300 filter, since I have read that incorporating it improves behavior. The truth is that it does work, but it is a very subtle improvement so I will soon put the one on the 125 again. I imagine that the throttle body has probably gotten dirty or swallowed dust and blocked a duct.
In your experience, what can cause this type of failure?
