Hello,

i have a strange probem with my blade: runs good until 5500rpm, then the engine starts stuttering in all gears. When pulling the full throttle in idle speed, stuttering too. The carbs are totally clean and calibrated, new carbs membranes, vaccum line is good, fuel pet **** works good, valve clearence perfect, engine compression check(perfect) all electrical wires are good, new spark plugs, air filter, air filter box not modified, no air leaks. Plug wires check. So everything is fully checked, but problem is not gone. Everything is stock, except exhaust muffler(it's Bos carbon muffler) I don't have any ideas what's happining.. maybe someone have more ideas?? (sorry for my bad english)

 

Sounds like it might be the fuel pressure regulator on its way out.

 

Mine doesn't have fuel pressure regulator, originally works on gravity feed🙂

 

ooppss of course not injected

 

Tank breather partially clogged? Try a run and open the filler cap when it starts to splutter (best not to have too much fuel in the tank at this stage ... :-) ).

 

Hello, thanks! Maybe🤔
I will check tomorrow😊