Promoto Billet power characteristics?

2 replies to this topic

Posted June 06, 2002 - 04:01 PM


I just recieved my promoto billet endcap and spark arrestor. The stinger appears to be about half the length of my stock exhaust and a little larger in diameter. I am wondering if this alters the power characteristics (running without spark arrestor). I know exhaust pipe lengths and diameter are carfully choosen. I think this different end cap will change things. What have you experienced?

PS. The quality of workmanship is great. I am very impressed with the machining.

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  • Bambislayer

Posted June 06, 2002 - 05:04 PM


I have mine in and cannot notice a difference. I do notice that now if I look back while at the gate with the bike idling, the dirt on the ground is doing all sorts of wierd things from the exhaust pulses, but powerwise, I notice nothing. Besides if you don't like the way it is, you could always buy a second hand stock pipe for the track.

I think the wierd pulses are generated because if you look inside the canister when you are installing it, you will see that where the stock endcap sat flush against the core, the pmb endcap does not. Now that I think about it though, this could just be because it is now easier to see inside the canister without having such a long stinger.

  • OR_Thumper

Posted June 06, 2002 - 07:14 PM


I have had mine for about three months now, and can not say enough good things about it, instalation was a breeze and no noticeable power loss.

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