Shorties with Cat?

ntst8 · Jul 29, 2021

I like the look of the factory shorties but the noise is obnoxiously loud so interested in whether anyone has run them with and without the Cat in place and if so what noise difference there is?
When my bike is back together it (with unlocked ECU) will be going on the Dyno so not worried about effects on the ECU mapping.

mean gene · Jul 29, 2021

Don't know how it relates to your Norton But On my Street Glide it made the stock pipes a Lot louder when I removed the CAT

ntst8 · Jul 29, 2021

Thanks, I was hoping/expecting that to be the case.

StuartSF2015 · Jul 29, 2021

ntst8 said:
I like the look of the factory shorties but the noise is obnoxiously loud so interested in whether anyone has run them with and without the Cat in place and if so what noise difference there is?
When my bike is back together it (with unlocked ECU) will be going on the Dyno so not worried about effects on the ECU mapping.

I agree, the shorties do look more sporty on the bike. I run decat with open peashooters but chose to slip on the shorties for a run to the new TVS Norton factory last weekend. The noise was just about acceptable to me on idle and low throttle. However, when accelerating they are so loud I think they could be heard in the next county. I’m not comfortable with that level of noise so slipped them off again.

Other owners run decat shorties and the exhaust note is nowhere near as load as my experience and the new 961 Classics are all fitted with cat and shorties. I wonder how load they are?

I‘d like to run the shorties but need a baffle solution to make the noice level acceptable to me.
Stuart

Fast Eddie · Jul 30, 2021

Cats definitely act as a very effective silencer, so I think that shorties and cats would quieten it down nicely.

However, I’m not sure where you’d be in terms of mapping and gaining the gains associated with letting these bikes breath?

Clive · Jul 30, 2021

I was interested that the new bikes have shorties as I seem to remember a Db rating for the bike; may be wrong but on the VIN plate? - probably part of the type approval. I wonder if they have a new map? Anybody know who developed the maps, by the way?

TonyA · Jul 30, 2021

StuartSF2015 said:
I agree, the shorties do look more sporty on the bike. I run decat with open peashooters but chose to slip on the shorties for a run to the new TVS Norton factory last weekend. The noise was just about acceptable to me on idle and low throttle. However, when accelerating they are so loud I think they could be heard in the next county. I’m not comfortable with that level of noise so slipped them off again.

Other owners run decat shorties and the exhaust note is nowhere near as load as my experience and the new 961 Classics are all fitted with cat and shorties. I wonder how load they are?

I‘d like to run the shorties but need a baffle solution to make the noice level acceptable to me.
Stuart

I think the shorties sound good.

ntst8 · Jul 30, 2021

TonyA said:
I think the shorties sound good.

I like the sound too, there is just a bit too much of it for me.
It does make it less likely that i would be rear ended, any following cars seem to be well behind me.
Comments about the new bikes are interesting thanks.

Stephen_Spencer · Aug 1, 2021

Gimme the volume any day! A bit obnoxious? Awesome! Let’s face it, it’s no open pipe Harley. Just adds to the visceral nature of the ride experience for me. That said, mine is a Sunday morning thrash machine - no touring on this instrument of torture!

Shorties with Cat?

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