Hello, this is a Honda rancher 420 fm, I have replace the spark plug and air filter and fuel filter. It idles fine and runs good up to about 2500-3000 rpms then it kinda acts like it's hitting a rev limiter. Any help would be great. Thank you

 

There is another fuel filter, in the injector. Injectors are difficult to remove on the 420 as you have to take out the little electric servo motor first, and the shaft on the end of it is easily bent. The tiny filter is in the inlet port of the injector and can be carefully poked clean then blown out with compressed air. It is also possible your pump is getting tired and not pumping enough fuel. You would need a pressure tester to check this.

 

Thank you merryman. I will certainly try to get at this filter. I've been thinking about trying to clean the iacv anyways although I don't think the iacv is the issue. I'm wondering if the MAF or the TPS could give me these problems. I'm also worried about the pump but I have no way of checking the pressure

 

Timing was off. Thx everyone

 

Ignition timing? Valve timing? How did it slip? The 420 has been Honda's most reliable engine since the 450, apart from one "heavy smoker" I've not had to work on a 420 engine yet. Unlike the back axle, I'm about to work on the fourth 420 rear axle in two weeks!