Fisch Moto Motorcycle/ATV Exhaust Spark Arrestor 

It's possible on both counts but _probably_ not dramatic, I would guess. Back-pressure would certainly increase with fouling (thus the periodic cleanings). I just spoke with a Yoshimura rep and was told that their spark arrestor insert is quieter than their noise-reduction insert (I asked because I must have the spark arrestor, but would also like some noise reduction). Granted, this is specific to the Yosh RS-4 and does not necessarily apply here. I have read that some of the maps for my Vortex ECU are specifically tuned for the RS-4 _with_ noise reducer, so that hints at potential back-pressure delta (again, may or may not apply to this product). If I notice any performance difference with the arrestor installed, I'll update here. I don't expect to.

You won't notice very much of an exhaust sound change after installing this.

I called the company personally several months back inquiring why the only Honda dirt bikes that show in their drop down were a crf 150 and 110. The lady told me it was not right . However, months later, still not showing any parts for a crf450r. I guess they are making so much money they don’t need to sell parts for our bikes !

@@johnberry2877 all you have to do is follow his directions. he tells you how to measure it...

Tried it on a 2007 Ktm 65. 20 mm. Was still too big. Had to Drexel some metal out to fit. Lost it first ride…expensive mistake!

the sport is booming. and yes, the price point is ridiculous.

Smells like broke boy in here.

@@Bcook928 idd 5 bikes in my garage, all bought new and the "race ready extras" mostly made in house. Now since you are a clever guy explain to us really slowly why ktm has basically 3 bikes atm under 3 different names that are exactly the same thing, the difference being the sub frame and the hidrolics. So now i ask you mighty keyboard warrior does it justify the gas gas being priced at 8.5 k and the husqvarna at 12k?

how did you find it?