Looking for new exhaust Buddy 170

[adamschopper]

I've heard that the prima exhaust system doesn't work optimally with the 170. Does anyone have recommendations for a performance exhaust that will work well with the 170?

[Skootz Kabootz]

I'm a little green at this but I think that any aftermaket performance exhaust on the 170i is going to require adjusting the EFI just as a performance exhaust on a carbureted scooter requires re-jetting. How one would adjust the EFI I have no idea. You would need the necessary computer program and to either get a hold of or create the correct profile.

[batgirl101]

I've heard that the prima exhaust system doesn't work optimally with the 170. Does anyone have recommendations for a performance exhaust that will work well with the 170?

I've had the Prima for 6+ months, it seems to work extremely well so far. regarding opinions that the pipe doesn't work with the 170, i'd be curious as to why not, perhaps someone can explain.

[PeteH]

When I was working with my dealer to mount up a Prima on my 150, the lead tech at Genuine/Scooterworks advised _against_ a jetting change. Anecdotally around here, those that do only go up a single size. This leads me to believe that changes to the 170's FI program might not be needed.

[AWinn6889]

I've heard that the prima exhaust system doesn't work optimally with the 170. Does anyone have recommendations for a performance exhaust that will work well with the 170?

I've had the Prima for 6+ months, it seems to work extremely well so far. regarding opinions that the pipe doesn't work with the 170, i'd be curious as to why not, perhaps someone can explain.

I thought you said in another thread that it caused you to lose a decent amount of top end speed? It is meant for carbureted Buddys after all.

For the OP, the 170i is still a fairly new model, I would make sure the proper software/flash is out there with the proper exhaust to match, before going through with anything permanent. I'm sure if you can't find anything right now, there will be something available by 2013.
I was told by the owner/lead tech at the Burlington shop that I should wait to see what else comes out, because EFIs can be a pain in the rear when you're adjusting either the intake or the exhaust. But he was very firm in saying that I shouldn't try just bolting on the Prima pipe meant for the 150s.

[batgirl101]

I've heard that the prima exhaust system doesn't work optimally with the 170. Does anyone have recommendations for a performance exhaust that will work well with the 170?

I've had the Prima for 6+ months, it seems to work extremely well so far. regarding opinions that the pipe doesn't work with the 170, i'd be curious as to why not, perhaps someone can explain.

I thought you said in another thread that it caused you to lose a decent amount of top end speed? It is meant for carbureted Buddys after all.

For the OP, the 170i is still a fairly new model, I would make sure the proper software/flash is out there with the proper exhaust to match, before going through with anything permanent. I'm sure if you can't find anything right now, there will be something available by 2013.
I was told by the owner/lead tech at the Burlington shop that I should wait to see what else comes out, because EFIs can be a pain in the rear when you're adjusting either the intake or the exhaust. But he was very firm in saying that I shouldn't try just bolting on the Prima pipe meant for the 150s.

it did lose some top, from nearly 75 to about 70, but the acceleration was terrific.

[JettaKnight]

I'm a little green at this but I think that any aftermaket performance exhaust on the 170i is going to require adjusting the EFI just as a performance exhaust on a carbureted scooter requires re-jetting. How one would adjust the EFI I have no idea. You would need the necessary computer program and to either get a hold of or create the correct profile.

If it's Electronic Fuel Injection then the computer should compensate for the reduced exhaust constriction by injecting more fuel. This of course assumes there is a O2 sensor in the exhaust. The whole point of EFI is to not have to deal with minor alteration and readjusting the fuel - the computer does it.

[PeteH]

Yeah, a high-end EFI will indeed sample the output O2 and adjust the mix. The high-end bikes have this, as do almost all car systems. However, I have not seen whether a 170i has an O2 sensor on its exhaust, nor for that matter whether it's on smaller [trans: less expensive] scooter engines on other makes.

Technically speaking, the O2 feedback portion of the loop isn't really mandatory when doing fuel injection (the older mechanical FI systems didn't have it), but obviously you'd lose the benefit of adaptive tuning and fuel consumption optimization. I'd bet that the cheaper systems just have a map that varies the input side based on temp, air, and load/RPM/throttle position.

I'd be really surprised if the PRC scoots that advertise fuel injection truly have O2 feedback. A pressurized FI system eliminates a lot of the fuel path problems plaguing carbureted systems, and that in and of itself is a good reason to design bikes with FI, even if there's no feedback loop.

[AWinn6889]

I'm a little green at this but I think that any aftermaket performance exhaust on the 170i is going to require adjusting the EFI just as a performance exhaust on a carbureted scooter requires re-jetting. How one would adjust the EFI I have no idea. You would need the necessary computer program and to either get a hold of or create the correct profile.

If it's Electronic Fuel Injection then the computer should compensate for the reduced exhaust constriction by injecting more fuel. This of course assumes there is a O2 sensor in the exhaust. The whole point of EFI is to not have to deal with minor alteration and readjusting the fuel - the computer does it.

There is not one O2 sensor on the Buddy, the range that the EFI in there could compensate for is very minimal, basically just enough to make the scoot not have problems changing elevation. The system on the Buddy is NOTHING like that on a modern car, it is more like those on the earliest of FI vehicles, with no feedback loop.
As for Fuel Injected Harleys, even though they don't have O2 sensors they do have a much wider range for air/fuel compensation than these scooters. However, if you want to change the air filter to something a little better than stock, or if you want to put louder/bigger/straighter pipes on there, you have to take it to a dealer for a new flash or a chip.
(HDM stands for "Hundred Dollars More" for a reason!)

Most cars these days have multiple O2 sensors, pre and post catalytic converter, which make them easier to tune because the ECU in a car can compensate for much more change than the scooter can because of the feedback from the sensors. With that said, even if you upgrade your air filter/intake and exhaust to stage 1 (or more) race quality in your car, you must get a chip, otherwise you would risk blowing up your engine (and/or turbo, if you have one like I do).