Quieter Exhaust Options (than Supertrapps)

My '86 700 has a pair of supertrapps on it. With 8 baffles, it's loud, stupid-loud. Sounds great, if you're wearing ear-plugs and don't mind irritating the neighbors. And don't go into parking garages (where it sets of every car alarm in the garage, instantly).

I'm moving to an apartment complex, and the bike will be in their parking garage.

So.

While the motorcycle is still welcome, I'd like to make it quieter.

I've tried running with fewer baffles in the past, and it ran very poorly (but was far quieter). From my poking, I think the design of the trapps yields a sharp-edged sound (and my recording of it is certainly full of sharp, high-frequency noise, much more so than recordings of staintunes or TBR pipes.

Stock is out, I don't want to go back to those beastly things (nor do I have them, or want to try and find them). Are there any reasonable, slip-on mufflers that might work? Honestly, if I could get a pair of smaller, slip-on Staintunes I'd be really happy. I don't need replacement pipes, just the cans.

 

Before you spend money try removing some of the discs on the mufflers. Suppertrapps get louder when discs are added & quieter when discs are removed.

 

Huh, I guess I forgot to add that bit: I pulled discs out about 2 years ago, from 8 to 4. It ran horribly, but was significantly quieter. I went to 6 discs, and it still didn't seem to run "right", and was happy at 8 discs. So.. Not sure what to make of it, unless it was, in fact, re-jetted when the exhaust was done (it's a full system). Which would have left it running extra-rich without all the discs.

Mostly I want a quieter idle and light-throttle operation. I don't care how stupid loud WOT is, so long as it has a good tone...

 

That you took out some discs was clear. Maybe try that again and save some pesos. Or, run the bike without any discs for a couple of weeks. The neighbors will complain; a natural state for the French... Then you go back to the original configuration of eight discs. You then become a national treasure and all kinds of French dudes will try to kiss you.

 

Sorry missed that part.

I remember the Cobra F! slip ons being pretty quiet. Problem will be finding them or anything else new for an 86. Have you looked into any universal mufflers? Or trying to re-jet after removing discs?

 

The bike is in California (and I will be as well in a month). But the bike is just nuts in a parking garage, as-is. Not too worried about pesos (it would be Euros here in france, btw

I see that TBR offers slip-on cans, for surprisingly little money ($300/pair?) But they really don't match the style of the bike with the new-style exhaust outlet.

Honestly, I think anything with a mellower, less raspy sound would make a bit difference.

 

I'm pretty sure any solution will be a universal-fit muffler (luckily that's an easy fit, so long as my pipes have a normal size). I think a larger dia, or longer body can would help considerably. The supertrapps don't have a lot of volume for packing material.

rejet is a possibility, but a pain since I'd have to have a shop do it (as I won't have a garage to do it in). Or I spend a day or two up at MotoShop in SF. But a rejet means pulling carbs, and these haven't been removed in ~28 years. So that's going to be an adventure for whoever does it.

 

Waiting until you get back to California might be the best solution for now. Can you roll the bike out of the parking garage to fire it up? Being near San Fran,
you still may have dudes trying to kiss you..

I had Cobras on a BMW airhead for a long time. Nothing wrong with those IMO.. I run a White Bros. (Supertrapp) on an SR500 with six discs and it's not loud. Bigger carb over stock by 2mm. 34 to 36mm Mikuni Put it on in 1981 and have never touched it since. Removed it once to put it on another head assembly I scored. No problems ever.

 

Yeah, I'm not going to be able to do anything about it until then, but I wanted to get the planning process started. My spaces in the garage are half a story underground, pushing the bike up the exit ramp would be a whole lot of "not much fun".

In the meantime, I can at least dig around and come up with ideas. Was poking at TBR and Yosh slip-ons earlier.

Of course, the other issue is that by the time I factor in the cost of a quieter exhaust, and the suspension changes I want, should I really just swap over to something else? Pick up a 5th gen that's still stock, and then get a new shock and the forks rebuilt. My current list for the VFR is to do either gold valve emulators or start looking into a F2 swap. But I think without space to do it on my own, I wouldn't do more than the valve emulators...

 

The underground ramp to ground level pushing a bike would not be much fun.. The noise would be enhanced too. I will take a guess that there is someone in that underground lot that has a fart muffler on a car and by now he is already the bad guy.. who never gets kissed

I have a Yoshimura can on my 91 that was on there the day I bought the bike in 91. Again never a problem..

I have gold valves in the 91 too.. They require careful attention and a very clean environment during installation.. Works Performance on the rear.. Once more no problems with either.

A newer bike is a newer bike. The 750's are great bikes and many of the dudes here like their 800s.

California in general has always been great for bike stuff so all these farkles could be easy to source.

 

Measure the end pipe and hit a bike yard when you get home, you should
find something cheaper and older style. In the meantime check out the sound clip thread
to get some ideas as to what you want it to sound like.

 

Moved in, and there are a bunch of bikes here, so I don't feel nearly so bad. Including a RWB '07 anniversary edition VFR. Haven't seen the owner of it yet, though. An SV 650 is parked next to us, and an F800GS is a couple slots away.

I'm still going to be doing the muffler work, but with less of a "must do it NOW!" sense of urgency.

 

Poking around a bit, I think my goal would be something that sounds between a stock 5th gen and a Yosh, TBR, or Staintune. The trapps are sharp and raspy, the others have a nice rumble to them. For a bike this old, it's clearly going to involve some custom work (or at least kit-splicing).

Looks-wise, I think a pair of Yosh TRS cans could work (especially nice with the insert in for commuting). But then the question is where to get them outside of a kit... or which kit to use as the base.

But before I can even do that, I need to get the mid-pipes/collectors measured for size.

 

I'd say you probably want to look around for megaphone slip ons.

Jose