Beta Riders Club Discussion Forum

300 RR:
Been running the Pro-Circuit Works but am curious about the FMF Factory Fatty and not sure what to expect. Thoughts?

Factory fatty same pipe as silver fatty performance wise.

Rode the Pro Circuit for 2.5 months or so. Just tried out the Factory Fatty today. First impressions: I want to put the Pro Circuit back on

What did you like better? Better low end or more top end.iI was told all the fmf are the same..

I rode the Pro Circuit on a lot of different style trails. It gives more torque and harder hit. It’s like it chokes up the engine low-mid (leaned out the pilot and needle diameter, as well as get the needle taper lower) and when the power valve opens it puts a nice smile on your face. So far, it feels more playful and definitely sounds better.

The only downside is that it is a large pipe and is close to the radiators brand new.

Does the pro circuit pipe stick out farther than the stock pipe? Would you say there's more torque down low

When the carb is tuned for it, for sure more torque and snap down low. It feels like all the power you need is just a 1/4 throttle away. It’s a trail pipe...Factory Fatty might be more of an open track pipe.

Edit: I don’t think it sticks out farther, just is closer to the rads. Banging it will make it rub on the rads quicker.

I need to back the horse up a little...

A couple days ago I accidentally made my PC pipe feel a lot like the FF. If you can tune the pipes to feel very similar, then the only benefit from changing pipes is fuel consumption. The FF needed more, and the PC needs less fuel.