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'93 muffler fell off, can I leave it off?

23 posts Started 29 May 2012 Last recovered post 30 May 2012 Wayback Machine snapshot 12 Sep 2017

#1

The muffler on my 93 came off (read: rotted and fell off) a few days ago. The sound really isn't that loud, compared to a Harley it is more like a loud whisper.

My question is, can I just leave it off and ride without terrorizing the engine in any way?

I'm not planning on having this bike for more than a few years, I've already poured a lot of money into it and frankly, I'm exhausted, no pun intended.

I've read that I could potentially burn up the valves but I've also read that that is not definitely the case.

I really dont want to spring for a new exhaust and I'd like to ride for a little while longer without breaking the bank on new parts for an ancient bike.

The sad thing about it is the last few people who have owned this bike did not take care of it. I went through hell repairing what I could and replacing everything else. In hind sight I would not have bought this Vfr but too late for that.

It's become a money pit and I just want another summer or two before its gone, is there a way to ride it with no exhaust and not kill the motor?

#2

was this the black one at crossroads cycle?

#3

It's my understanding that if the pipe is short that cool air can back up to the valves, and that causes them to get damaged.

You could go to a junk yard and get something cheap.

#4

The muffler broke off right where the flange bolts to the collector box. I read about the cold air getting sucked in and warping the valves also buy most of those complaints came from people who had bad header gaskets and the air was entering there at the block, not back up through the exhaust.

Im wondering if I play with the choke lever if that would help enrich the fuel mix, cut down on the heat from a leaner mix due to loss of back pressure.

I wasn't at crossroads, I was at Rockville Honda on Randolph this Saturday though.

#5

I asked because there was a 93 at crossroads, and it too had no muffler. The stock exhaust must have a pre muffler because it was really quiet without a can.

I don't think you will hurt the motor, and if it is as quiet as the one I saw, it's just personal taste at this point.

#6

Monk, I was going to take the junkyard route like you mentioned but I'd rather just leave muffler off all together if possible.

#7

Timmy are you really a cop?

I don't think I'm breaking any noise ordinances but I still don't want a ticket.

The collector box has a baffle-like structure built into it, not sure what it's for but it seems to also aid in silencing the noise from the engine.

I'm surprised the bike isn't louder with the muffler gone. It's really not as loud as one might expect.

Edited May 29, 2012 by Civilizeddog
#8

With the extra info given, I'd agree with Timmy, let it go.

#9
Civilizeddog

Timmy are you really a cop?

No, but I did stay at a holiday inn last night.

[image: Photo_040611_001.jpg]

Dont worry about John Law. The HDs are a ton louder, and they are never cited.

#10

It seems you are not too concerned with aesthetics, so there must be someone here with a lightly rashed muffler hanging in their garage they would let go for cheap.

Running with an open header is an invitation to the masses to bash our sport, and gain you attention from Johnny Law, regardless of what the Harley boys do or don't.

#11
Veefer800Canuck

Running with an open header is an invitation to the masses to bash our sport, and gain you attention from Johnny Law, regardless of what the Harley boys do or don't.

normally I would agree, but that pre-muffler thing makes these bikes really really quiet. The one I saw had no end can at all and was just barely louder than stock. quieter that staintunes with the spuds in.

#12

On a carbureted engine, the amount of intake/exhaust flow in conjunction with the jet size determines how rich/lean an engine runs. If the carbs are tuned for a a muffler (more restrictive) and then the muffler is removed or falls off, the engine will (theoretically) run lean. This is what causes the valve damage....they can get burned if too lean. I'd suggest maybe replacing the spark plugs and then reading them (color) to see where you stand now that the muffler is gone. If running lean, you can step up the jet size or just get another muffler.

Chances are, though, if the muffler has been bad for a while, it was pretty leaky for quite a while and it's still running. If it's like Timmy says above and there's another muffler somewhere in the system on that bike, the outter muffler may not have been doing much anyway....not sure how they were on the 93s. Worth checking the plugs though.

Edited May 29, 2012 by IndyFour
#13

Definitely worth checking the plugs, I agree.

I found a really interesting article online while researching my predicament. I want to provide the link just because it may be usefull/ helpfull for anyone else in my shoes that may stumble over this post.

http://my.prostreetonline.com/forums/archive/index.php?t-1639.htm

I didn't write it obviously and it is meant more for car tuning but some of the theory also pertains to motorcycles.

Timmy, nice carbines!

#14

Timmy, do you have AR-15A1 tattoed on your "guns"? :tongue:

#15

Those are actually M16-A1s. Given to our department by the US Army.

#16
timmythecop

Those are actually M16-A1s. Given to our department by the US Army.

If it was a high res enough shot to see the selector, I could have told you that. Most depts. around here only get to play with semi autos, so I had to guess that direction. :beer:
#17

You did get the A1 part right.......

#18
timmythecop

You did get the A1 part right.......

Teardrop (best i can tell) forward assist, skinny barrel, bird cage, triangle handguard, rear sight windage only...Can't miss on the A1, even without a sharp image. :cool:
#19

I have an extra 5th gen muffler I might be induced to part with for small money + shipping. I do not know if it will fit. Anyone?

(I'd replace my imperfect stock muf. on my 100,000 mi with a better one and the old one would be available cheap.)

#21

It is nice, but you still need and end can. That system WILL be too loud without one and it will prolly run like poop.

#22

im running no muffler on my 1990. love it.not too loud. but a great v4 rumble.

i slip the muffler back on for long trips

it was my understanding that a muffler is just that, muffles the sound

back pressure is figured out in the header bends and collector box

mufflers weigh a ton

love the open wheel look

you can fit 1990-1993

but even used they are pricey

try and mod a slip on

#23

One of the mods I did this winter was yank the 93 subframe and swap it with an 08 cbr600 subframe and tail.

I integrated the tail lights with the viffer's wiring harness. I have my friends 08 cbr600 stock exhaust which I will have fit to a flange that connects with the end bit of the new exhaust.

That was always the plan before the muffler snapped. Was just gonna adapt the cbr can to the stock collector but its too late for that now.

There is an exhaust fabricator in Pasadena Maryland about an hour away. If I pick up that one one eBay I'll make a trip up to the shop and have them take a look.

End of thread · 23 posts recovered Wayback Machine snapshot 12 Sep 2017