Lifan KPX Throttle Response / possible detonation - Page 3

MotoJane · 05-08-2024, 04:17 PM

Quote:

Originally Posted by JerryHawk250

Do you have any video so we can hear? That would really help in diagnosing the problem.

Venom is in the building! They've called me! As for the sound, I've sent them a clip of it and they told me to stop riding the bike. They are working with the manufacture and we are on the road for a warranty issue. In the interest of the warranty and not wanting to hurt Lifan I'm not going to upload the video. I understand things happen, it's normally a one off, but this is the world not a video game.

MotoJane · 05-08-2024, 04:22 PM

Quote:

Originally Posted by J4Fun

With respect here, after adjusting the valves and it went from bad to worse, that’s pointing to the valves. We’re assuming that the engine was on the compression stroke when the valves were adjusted? Easy to to get things wrong here. Plenty of info. on how to adjust them here. Thinking out loud…

As I said I did have a real mechanic helping me with the adjustment. I agree something in the valves on this bike is seriously wrong and it isn't an adjustment. Maybe they aren't seating correctly or they are bent from the factory. I'm not sure but the way the sound of this engine something is seriously wrong.

Thumper · 05-08-2024, 06:33 PM

Quote:

Originally Posted by MotoJane

I picked up my KPX 250 a couple of weeks ago and I'm having the same issues as others with the ping/click during acceleration. I don't hear it at speed or idle just when I'm going through the gears. It can be loud so with a helmet on I have no issue hearing it. I checked the provided manual and this bike has no gulp screw. No adjustment screws at all that I can see on the 2023 KPX 250. Anyone find a solution to this issue? I only have like 50 miles on the bike. I contacted Venom the folks I got the bike from with zero response.

Sounds like classic lean mixture. Good luck. Some folks do OK with it, but others have excessive lean issues.

My "primitive" carbed bikes can't adjust automatically for elevation/temperature. Nothing over 500 feet in evelation within 500 miles of here, but I will be moving. So I will rejet accordingly. You can do that with a carburetor.