nytro exhaust

[uker7]

decided to experiment with exhausts on my nytro because stock sounds terrible. i tried straight piping it but that was just to obnoxious, ended up rigging up a pipe from my buddies yfz450 (quad) and it sounded great, that is after a drilled a few holes through the center plate in it. now i know everyone says that a 4 stroke doesn't need back pressure but with this can on im hitting my rev limiter after being on the throttle for 2-3 seconds. so does a 4 stroke need a specific amount of back pressure or am i missing something here?

 

[M5-]

It's got nothing to do with back pressure, less back pressure the better on the 4 stroke. You will pick up 2-300 rpm with the pipe. When are you hitting the rev limiter? With the Nytro if you are clutched right for the hills you will most likely hit the rev limiter on the trail or flats. Mine bounces off the limiter on the flats but pulls down to 8600 and holds on a pull.

M5

 

[347strokin]

decided to experiment with exhausts on my nytro because stock sounds terrible. i tried straight piping it but that was just to obnoxious, ended up rigging up a pipe from my buddies yfz450 (quad) and it sounded great, that is after a drilled a few holes through the center plate in it. now i know everyone says that a 4 stroke doesn't need back pressure but with this can on im hitting my rev limiter after being on the throttle for 2-3 seconds. so does a 4 stroke need a specific amount of back pressure or am i missing something here?

I hear you on the straight pipe. Mine is straight through the turbo and is too loud for me, especially when on the trails. I will be putting some kind of muffler on it in the future.

 

[uker7]

It's got nothing to do with back pressure, less back pressure the better on the 4 stroke. You will pick up 2-300 rpm with the pipe. When are you hitting the rev limiter? With the Nytro if you are clutched right for the hills you will most likely hit the rev limiter on the trail or flats. Mine bounces off the limiter on the flats but pulls down to 8600 and holds on a pull.

M5

well i havent tried it in the mtns yet. its hitting about 9300 rpm when its bouncing off the limiter. so you think this is alright and will probably go away up in the hills

 

[M5-]

I expect it will come down on a pull. I haven't found any setup that allows you to be at peak power (8800 rpm or so) on a pull and also keep you off the rev limiter on the trail. Just go easy on the trail.

M5

 

[baapex]

agreed I have aftermarket axhaust and tightened down the secondary on my apex, and on firm snow or trails i can easily hit the rev limiter, I just try to take it easy there, but in the steep and deep it is sweet! This is the only way to go imo. Dealer says its fine too.

 

[uker7]

well thats good news, i guess ill leave it on there and try it out on the hill. thanks