Noisy exhaust on '81 Midnight Special

[jpilk99]

I have stock exhaust (I believe; black 2-into-1s on both sides of bike) and I get a noisy/rattly noise when I go about ...1500/2000 rpms or thereabouts. Low rps is fine.

Bike mechanic said these pipes are almost like a "2 part" with a pipe inside the pipe. If this is the case, I can't picture being able to remedy the pipe itself; right? It's only the "passenger side", right side, pipe.

As you can imagine, it's annoying as all get out. I looked on Craigslist and ebay for one and didn't see - will keep looking. I kinda think I'd prefer to stay stock, but, availability may have a big input on that. I wouldn't mind a little throatier sound; but then obviously I'm doing both...

Thoughts please. Thank you!

Jay

[dpotter58]

Yes, what the mechanic told you is correct. The pipes have an inside pipe at the headers and sometimes that comes free and rattles. Baffles rust and can be a source of noise near the rear. Also, the crossover tubes have a clamp that may come loose or they could just be mounted loosely on the foot peg brackets. have someone hold the throttle open and pinpoint the source. If it's only the noise that bothers you keep the pipes. The black chrome are like hens teeth to find and aftermarket pipes don't measure up looks or performance wise.

[jwhughes3]

If the pipes are toast anyway you may try this (mind you its just an idea I had and you are the guinea pig).

There is a muffler repair kit for sale - I think Pep Boys has it and probably others that has a patch and large tube of exhaust ready putty/paste with it for attaching the patch. We do not need the patch.

On the under side or backside of the rattling pipe near where it rattles drill a 1/8-3/16" hole being careful to only go deep enough to barely go through the outside pipe and squirt the paste into the middle between the pipes to dry in place and act as a "buffer" between the pipes.


Willing to experiment?

John

[jpilk99]

Thank you both for your quick responses.

I'll keep looking for someone who may be selling parts off an original; though obviously they may have the same problem. I'm a little surprised that you don't feel that any aftermarket would be a good replacement, if not upgrade.

I'm all for trying something to see if it helps. I'll do my best to isolate where the vibration emanates from. I'm not usually so lucky as a lose connector bolt that needs tightening, but, I'll check so as to eliminate that as a possibility. Will consider the "lab rat" test thereafter and let you know.

Thank you!!!

Jay

[DiverRay]

You should also look at the "covers" over the pipes in front of the foot pegs. The bolts will rust, and the covers will start to rattle. I've lost both covers on my MNS, even after trying to TIG weld the nuts back on to the pipe.

[cajun31]

aftermarket

There are aftermarket pipes for your bike, however most of them are chrome not the black chrome you now have. I saw a set of 4 into one by mac on ebay just the other day. They are ceramic painted black. Good luck on finding a set of oem. They come up on ebay every blue moon and are priced according to their how rare they are. Often too pricey and most of the time an incomplete set. I have been looking and waiting for years to try to score a set. Best options would be to go for the fix first and if that fails, aftermarket chrome that you could ceramakote or jet hot black. Good luck in your search.

[motoman]

I have stock exhaust (I believe; black 2-into-1s on both sides of bike) and I get a noisy/rattly noise when I go about ...1500/2000 rpms or thereabouts. Low rps is fine.

Bike mechanic said these pipes are almost like a "2 part" with a pipe inside the pipe. If this is the case, I can't picture being able to remedy the pipe itself; right? It's only the "passenger side", right side, pipe.

As you can imagine, it's annoying as all get out. I looked on Craigslist and ebay for one and didn't see - will keep looking. I kinda think I'd prefer to stay stock, but, availability may have a big input on that. I wouldn't mind a little throatier sound; but then obviously I'm doing both...

Thoughts please. Thank you!

Jay

If you'll pull the right side exhaust and look in top part of header of #3 pipe and header end of #4, you may see inner pipe has a fractured piece. It CAN be welded with a wire-feed and dremeled back fairly smooth...BTDT, as I have both type welders.........considering the rarity if decent pipes, would be worth havin' a look-see, if you find no external loose pieces.

[jpilk99]

4:1 or two 2:1?

Would you recommend going to a 4:1 or staying with the two 2:1s? I'm not looking for any major jump in performance, but, a little more uuuumph is not a bad thing. Certainly wouldn't mind a LITTLE more tone/throat.

Thanks.

[motoman]

Would you recommend going to a 4:1 or staying with the two 2:1s? I'm not looking for any major jump in performance, but, a little more uuuumph is not a bad thing. Certainly wouldn't mind a LITTLE more tone/throat.

Thanks.

Not only would be a downgrade in value, but also a downgrade in performance.......that's a given........but, it's your ride, do whatever the hell you want.

[motoman]

Not only would be a downgrade in value, but also a downgrade in performance.......that's a given........but, it's your ride, do whatever the hell you want.

BTW, no offense intended, just tired of newbies thinkin' they know better tryin' to re-invent the wheel........ain't happenin', least not with THESE scoots.

[cajun31]

fixing the pipes

is your best option if that is a feasible alternative. Those stock exhaust add to the value of the bike. Unless the bike is in near mint condition to begin with then having or not having the stock exhaust is relative. The midnights usually bring a better price when selling. Now with that all out of the way, going to either a 4-1 or 2-1 by itself is not going to give you any performance gains. I have a kerker 4-1 on mine and I do like the sound of the pipes, however I did not get any performance gain from them. By the way the kerker's are no longer available unless you can find a set of nos on ebay. If you do a search on the web you will find several other choices around the world. Check out the UK xs11 site. They have a thread they started that shows all the pipes they could find. They actually had to close the thread because of all the sites and pictures listed. Unfortunately the thread now has some age on it and most of the sites listed are either no longer valid or the pipes listed are no longer available. The only pipes that are available on an everyday basis and easily found are by mac. They come in several variations to meet your wants and needs. The only knock on them is they are single walled and durability is questionable. My recommendation is you go that route is to coat the inside of the headers with a high temp ceramic paint for added protection and keep them clean on the outside. That may make them last longer.

good luck on your search, but first try to find the source of you problem with your existing pipes and make the needed repairs. Especially if they are still in pristine condition on the outside. If you don't weld most muffler shops will do those repairs for you at minimal cost.

[cajun31]

here is the thread I was talking about

http://xs1100.com/forum/index.php?topic=5436.0

[jpilk99]

BTW, no offense intended, just tired of newbies thinkin' they know better tryin' to re-invent the wheel........ain't happenin', least not with THESE scoots.

That's why I asked the question, Motoman.... thank you for the enlightenment. Geru eh? You gave yourself that title, right.

[jpilk99]

Thanks Cajun. My goal is to rid myself of the rattly noise; first. If doing so requires new pipes, I've heard/seen pros and cons of 4 or 2:1. I'm not so concerned with maintaining any resale value; I'm keeping this bike. I just want a reliable enjoyable ride ...and then I guess at the most affordable cost :-).

I believe I've found the rattle. Let's see if I can remedy it.

Thanks again for the positive suggestions/recommendations.

Jay

[jpilk99]

If you'll pull the right side exhaust and look in top part of header of #3 pipe and header end of #4, you may see inner pipe has a fractured piece. It CAN be welded with a wire-feed and dremeled back fairly smooth...BTDT, as I have both type welders.........considering the rarity if decent pipes, would be worth havin' a look-see, if you find no external loose pieces.

Great advice - I will give this a look too. I believe I've found the rattle down by the right footpeg; but it's internal.