revtothelimit - motorbike forum

...but will this make them so on bikes?

Good idea but looks shit

Nothing new.
I considered a system for the Harley many moons back but decided against it as it was fully EU ECE compliant and TuV approved, oh and costs started at £2k.

https://www.jekillandhyde.com/en/brands ... on-exhaust
https://www.bennetts.co.uk/bikesocial/r ... t-breakout

There've been switchable exhausts on bikes for decades, they've just been focused on performance rather than noise.

Who remembers the Quill exhaust that had that ball in chamber design? As the revs built and more gases were put into teh exhaust, it moved a ball thing out of the way and the exhaust became a sort of straight through, or something like that. I had one ona CCM and it was pretty good for sneaking past Plod but volume when you wanted it.

Yoshimura used to have a sprung flap on some of their pipes before the end can, a very primitive exup system, but it complied with whichever race series they were in!

Got an exhaust valve of some sort in the cbf1000, not sure what it does apart from getting seized and messing up the running of a great motor after a while. That monstrosity up there can certainly get in the sea.

https://vandemonperformance.com.au/prod ... on-muffler
This seems like a pretty good effort.

I would love to be able to quieten my exhaust, particularly when riding through tiny streets with high buildings either side.

I've just repacked my exhaust, unfortunately I didn't buy enough packing material, so now its noisier than ever

Next delivery of exhaust packing early next week I hope !

Taipan wrote: Wed Sep 03, 2025 11:03 am Who remembers the Quill exhaust that had that ball in chamber design? As the revs built and more gases were put into teh exhaust, it moved a ball thing out of the way and the exhaust became a sort of straight through, or something like that. I had one ona CCM and it was pretty good for sneaking past Plod but volume when you wanted it.

I had one on my CB-1. They called it a T3 silencer and they sounded great with a real on/off switch around 4500rpm. Especially handy for a small IL4 where it was quite easy to enjoy the noise at legal speeds, or choose not to.

I bought an oldish Quill can on eBay for my CBR250 thinking it would have that, but it's just a basic absorption silencer. But it's whatever came after, the Evo2 I think. It's still a bigger volume silencer than a normal bean can so it sounds decent, albeit it's not what I had it mind.

These days Quill is just another brand name for MTC exhausts. They aren't anything special technology wise.

It's a damn shame that technology was lost.

Jody wrote: Sat Sep 06, 2025 9:47 am I would love to be able to quieten my exhaust, particularly when riding through tiny streets with high buildings either side.

I've just repacked my exhaust, unfortunately I didn't buy enough packing material, so now its noisier than ever

Next delivery of exhaust packing early next week I hope !

You can get dB killers that look like catalysts which go before the silencer. They knock off a few dB's, might be enough to do what you want.

v8-powered wrote: Wed Sep 03, 2025 10:34 am Good idea but looks shit

Looks like a kitchen gadget, from bid-up TV.

Thornton Hundred have been using Jekyll and Hyde exhausts on their Triumph Bobber builds for a few years now.