Beberapa knalpot racing pun di rancang untuk memenuhi aturan polusi suara

Aturan yang akan saya sebutkan di bawah adalah aturan yang berlaku di daerah masing-masing. Beberapa negara seperti di US, Australia punya ambang batas yang ditentukan Environmental Protection Agency (EPA). Batasan per negara bahkan per negara bagian bisa berbeda-beda. Eropa pun punya labeling (CE marking), CoC, untuk memudahkan kendaraan lintas negara antar anggota EU.

So, kalau dalam postingan ini saya sebutkan boleh dipakai di jalan sesuai aturan, maksudnya adalah boleh dipakai di US, Eropa dan lain-lain, bukan di Indonesia. Tidak ada jaminan bisa adu argumen dengan polisi Indoensia, “knalpot saya sudah memenuhi standard!*” Standardnya luar negeri maksudnya…

Ok, langsung lihat beberapa knalpot imporan yak.

Yoshimura

http://www.yoshimura-rd.com/t-NP_11_EPA_SYSTEMS.aspx

Yoshimura has dedicated hours of research, development, and extensive testing to bring you EPA Noise compliant exhaust systems. These slip-on systems offer the craftsmanship, attention to detail, and high quality that Yoshimura has prided itself on for over fifty years.

Contoh salah satu produknya adalah ini: Tipe R77, stainelss carbon untuk Kawasaki ZX10

This Yoshimura exhaust component or system meets EPA Noise Emission requirements of 80 dBA when installed on the specified motorcycle. Installation of this exhaust component or system on motorcycle models not specified may violate Federal Law.

Sayangnya menurut website, tidak ada knalpot Yoshimura untuk Kawasaki Ninja 250 yang comply EPA. Pada ketiga tipe untuk Ninja 250R,  TRC, stainless, carbon, titanium. Ketiganya disebutkan dengan jelas:

For Closed Course Competition Use Only. Not Intended for Street Use.

Two Brothers

Di footer sejak halaman homepage/index disebutkan dengan jelas demikian:

©1985-2013 Two Brothers Racing, Inc. TBR products are intended for closed course competition only. Not legal on public roads, streets, or highways.

Jadi lain dari Yoshimura, yang masih ada produknya yang comply ada yang tidak, Two Brothers memang tidak membuat knalpot untuk di jalanan. Two brothers memang punya produk untuk sound suppresor, tapi hanya mampu menurunkan suara maksimum 8 dB.

Akrapovic

Kalau di website mereka menyebutkan demikian:

Akrapovič’s Slip-On Line is designed for recreational riders. These exhaust systems are easy to install and they replace stock mufflers. They will give you more power, more torque and less weight and consequently asmoother ride. Most versions are with EC type-approval.

Alias hampir semuanya yang mereka jual adalah EC approved. EC approved belum tentu aman digunakan di US, mereka pun mengeluarkan box seperti ini, khusus untuk California.

EMISSION NOTICE

Please note that certain aftermarket exhaust systems may not comply with applicable California laws and regulations, and may therefore be prohibited for use on California highways or roads, or on roads or vehicles otherwise subject to emissions control requirements.

Akrapovič exhaust systems for automobiles and motorcycles mounted downstream of the catalytic converter (also known as “cat-back systems”) are considered “replacement parts” in California by the California Air Resources Board (CARB), and do not require an exemption or executive order from CARB to be sold in California. However, California prohibits the use of any aftermarket exhaust system that modifies, removes or replaces original equipment catalysts, unless CARB has issued an Executive Order as to such part or system.

Further, Akrapovič parts or exhaust systems used or intended for use on “racing vehicles” (i.e. a competition vehicle used exclusively for competition on closed-course circuits) do not require an exemption or Executive Order from CARB to be sold in California. However, such parts are prohibited from use on California public highways or roads, even if occasionally used “off-road.”

Begitu para bro.