Hello from Central West NSW

[hybrid]

I'm certain my bike didn't lose power by butt dyno with the internal stingers, but maybe that's because the pipes weren't perfect in the first place - who knows. Even if I lost 2-3HP I would still prefer it for the sound level on the RD.

[JonW]

I agree johnno and Jeff, I also need effective silencers. Ive mentioned it before that the cops set up an RBT thats right at the end of my driveway so I run into them every time I consider riding and theyve already stopped one of my mates for noise on an RZ250 with pipes.

Few guys seem to have the same noise reduction needs as those of us in NSW it seems, so its hard to find info... but what little i have Ive found was based on bigger end cans with more wadding. Also with thicker silencer walls too i guess, tho some say that walls made of something other than hard materials help, ie CF. But really I feel that you need to put some kind of baffle in the way with angled plates across some of the flow which i guess defects the noise into the wadding, of course this will be at the expense of flow speed, but that's probably too high anyway as doenst need to exit straight out to be effective. Of course thicker gauge bellys will also stop some of the ting ting noise, and lining them internally with mesh would help, all tricks the OEMs use on their pipes, but it makes them heavy. Its also interesting Lozza says that OEM MX pipes outperform aftermarket units, if you look at any LC/RZ pipes test you see that OEM LC 350 pipes make almost as much power as the modern aftermarket units even with all the modern clever tech involved in building them, the OEM units may be heavy and quiet, but the perform fine.

Happy to hear more info on this topic as its dear to my heart and I really do need to silence my 421 LC as its silly loud on spannies with small cans, and I really do need the big bellys so cant go OEM...

[hybrid]

John, if you have a spare set of pipes I'm happy to help you make up some internal stingers to test.
A mate of mine has my welders on loan at the moment, but when I get them back I'm happy to help.

I just got some steel tube from bunnings - they had a size that just happened to be perfect ID.
I really should have taken more pics at the time, but forgot all about it.

Edit: this was my thread:
viewtopic.php?f=3&t=897&p=5774&hilit=in ... gers#p5774

[OzzyElsie]

For Johno....

https://www.youtube.com/watch?v=nPQPuRo7vhk

Your blog shows an interest over and beyond old smokey, smelly 2T's. You may have seen it already but wait 3-4 passes and then it goes Full Noise - glorious

[oldjohnno]

John, if you have a spare set of pipes I'm happy to help you make up some internal stingers to test.
A mate of mine has my welders on loan at the moment, but when I get them back I'm happy to help.

I just got some steel tube from bunnings - they had a size that just happened to be perfect ID.
I really should have taken more pics at the time, but forgot all about it.

Edit: this was my thread:
viewtopic.php?f=3&t=897&p=5774&hilit=in ... gers#p5774

I've rolled up more chambers over the years than I've had hot dinners, and with all sorts of stinger and silencer configurations. What I've found is that any stinger that exits from anywhere other than the end of the baffle cone has to be quite a bit bigger than what you'd normally use. The other thing I've found is that an absorption style muffler (perforated core glass-pack) has flow characteristics that are very very different to an equivalent plain tube. The difference on a running engine is even more than what's measured with steady flow on a flow bench (yes I have one of those too).

The other thing I've found is that a baffle type muffler - if it's dimensioned just right - will be as quiet as a glasspack but actually flow better. I suspect that some experimentation with these could pay off.

[hybrid]

Pretty sure my ID is now 1-2mm bigger than it was, but can't remember exacts.

Sent from my OnePlus One using tapatalk

[oldjohnno]

JonW, what I'd like to know is why those fat boys on their FatBoys can ride around with open pipes, seemingly with impunity. Anyone else making that much noise would cop a ticket quick smart...

[OzzyElsie]

JonW, what I'd like to know is why those fat boys on their FatBoys can ride around with open pipes, seemingly with impunity. Anyone else making that much noise would cop a ticket quick smart...

I don't know the reason why/how the Fatboys get away with crap when others don't - safety in numbers???? But what shits me is not their noisy bikes but they use them nosily - they seem to have small weeners and need the attention - attention seekers.

[hybrid]

Harley putting rev limiters on their bikes is the worst thing they ever did.
There's some wanker around my place that rides around on the limiter all the time.

They sound like shit. I don't know why you would want a loud one.

[JonW]

I agree that the harleys are overly noisy and they do seem to get away with it, the cops almost love them... perhaps the cops are in bed with the bikie gangs, who knows :/

Where I live at the intersection of a 2 busy roads I often hear the bike gangs riding north and south, fek you really know noise when 50-100 harleys takes off from the lights, not impressive at all. wankers.

[OzzyElsie]

..... fek you really know noise when 50-100 harleys takes off from the lights, not impressive at all. wankers.

They call that 'rolling thunder' - and they get off on it.

And if you react pissed off, they like it even more.

And if women or children react intimidated they like that even more.

Go figure. Most of them couldn't ride outa sight on a dark night, wankers. Most of them would be better off putting their $60,000 into psychotherapy. But I'm only saying that because I'm jealous and can't afford a Harley. If you don't believe me just ask them. If you want a second opinion ask any two of them. If you want a third opinion.........

(Rant off - I'm starting to feel the benefit of my morning meds )

[JonW]

haha, yeah its a bit early for ranting, and too bloody hot on this 'about to be 40+ day' in Sydney :/

Rolling beehives is what we need... LOL

[OzzyElsie]

Hey Johno, I've been reading ya blog - love ya work, you sound a bit like of a Burt Munro of 2T's . You must have an awesome garage or a indulging boss .

Your work with the reed blocks is interesting. I have work with mine to a minor degree - checking, opening up slightly etc - but never worked on the 'lead in' of those rubbery bits. I've looked at them pondering but never done anything - there always been easier and proven issues like bigger carbs to play with. But, thinking, thinking, thinking .......it might be worth of a fiddle.

[oldjohnno]

Hey Johno, I've been reading ya blog - love ya work, you sound a bit like of a Burt Munro of 2T's . You must have an awesome garage or a indulging boss .

Your work with the reed blocks is interesting. I have work with mine to a minor degree - checking, opening up slightly etc - but never worked on the 'lead in' of those rubbery bits. I've looked at them pondering but never done anything - there always been easier and proven issues like bigger carbs to play with. But, thinking, thinking, thinking .......it might be worth of a fiddle.

Hey Ozzie,

Hope you don't mind me taking this over to the new Tech section - prob. makes more sense to be over there than here in the introduction pages.

[2TInstitute]

Thanks for your reply Lozza; it'll be interesting to see how EngMod2T assesses the current port layout (which is basically all Blair) and also what is left to be gained. I may start a thread showing its assessment of the current and proposed layouts.

Internal stingers cost hp an effective silencer is much much better.

You've just convinced me to revert to a conventional stinger. But what's an effective silencer? Keeping in mind that this is a streetbike? Noise control is important enough to me that if I have to sacrifice a HP or two then that's just what I have to do. I just don't need any unwanted attention from the po-po..

making an effective silencer is dead easy. First is point the outlet at the ground so out of the end can has a radiused spout that points the noise down. That can knock off 4-5dB there alone. Next is the perforated sheet get >85% open area, packed with the string type packing you can get from Ballards dirt cheap. Pack it reasonably loose for any noise tests and tight as a nuns ninny any other time. Then make it big and long carbon works best. TYGA made 400mm 28mm bore silencers for the TSS500 they work a treat Done.
If you want to get real sneaky and you have a 2 map programmable, just make a real soft map for map 2 flick it to that if your worried. Yamaha did this with a YZ250 being used for Enduro in Europe, had a gear position sensor in neutral where the noise testing was done. A completely different map in neutral.