Noisy exhaust on '81 Midnight Special

[cajun31]

That is exactly

where my original pipes cracked. I am talking about all the way through. I hope that is not what you are seeing. If it is I would suggest taking the muffler cover off then ride to your nearest muffler/welder and have them tack it back together while still on the bike. from there you can remove that side and have them do a more thorough weld. Any other way and you will have alignment problems.

[motoman]

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

Nope ........not even close...........but stick around and follow advice from us ole'timers and you accidently could very well have sweet runnin' bike.

[TopCatGr58]

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

Hey there Jay,

Brant/Motoman already responded to this, but I'll add my 2 cents. As he said, no offense was intended. He is a veteran of many decades of actual professional mechanical experience with these machines, as well as others in both street and racing applications, so he knows quite a lot about these bikes, what makes them run, what can help them run better or not. You've only been on here for a short while, and probably haven't done too much searching and reading of past posts/threads or you would have found that the Yamaha Engineers developed the OEM exhausts for the best ALL AROUND performance that can be gotten out of these engines. They have a crossover pipe for balancing, and dual layered mufflers as well to provide the required backpressure/ reduction of the exhaust pulses/waves which gives great low rpm throttle response as well as midrange and decent top end...most folks don't run these bikes near the 7k rpm range for very long.

ALL of the aftermarket pipes that were available did not have the crossover balancing pipe, Jardine did a fair job in trying to link the 1-4 and 2-3 pipes together in an attempt to have better balance of the scavanging affect and the exhaust pulses/waves....vs. other brands that linked 1-2 and 3-4 together on both sides. The 4-1 pipes Do provide a better scavanging affect, but pushes the powerband up a bit since they scavange better with higher velocities/speeds that are encountered at the higher rpms, but because of their reduction in backpressure, most folks report an actual LOSS of low rpm torque/grunt....which is where most folks tend to run the engine rpms at, not WOT or 7K+ all the time.

SO...this is why if you have a decent set of OEM pipes, that it will serve you the best to find a way to repair/save and continue using them, vs. putting on an aftermarket pipe whether it be 4-2 or 4-1.

And the USER TITLES are assigned by the website as markers of tenure and how many posts one has contributed....it's felt that when a member has been on long enough to have posted 1000 posts, they have then usually learned enough to have earned the GURU title, then it changes with additional levels of posts. Granted just chatting in the Member's Lounge could allow someone to rack up 1000 posts without really learning or contributing much techwise, but nobody does that.

This site is here to help fellow bikers with these same bikes to keep them running, get them running, repair them with the least amount of expenditure or damage, etc.! No one is PAID to be here, it's altruistic all the way, and I am grateful for the knowledge base that is our consistent members and posters.

Just some FYI to show you where WE are coming from!

Good luck with the repair.

[jpilk99]

Thank you, TC

Without wasting too much time defending myself:

I'm as altruistic as they come. I'm more of a muscle car hound, 49 years old, and a solid "driveway mechanic". I've done a frame off restoration of a '65 Buick Riviera Gran Sport and did everything myself other than having the engine cylinders bored.

So, when I ask what I believe was a ...pretty straight forward/normal/logical question - to have someone belittle me with "these newbies don't know nothing"... Just not a respectable way to treat another fellow motorhead.

Enough crying. Your write up is fantastic. I was just having a very similar conversation with my 16 year old son about the balance between having a restrictive exhaust and no exhaust at all. The harmony between enough backpressure to allow an engine to run optimally vs. restricting the engine's ability to "exhaust" the combustion chamber's afterburn and thus losing power to push that exhaust out through the pipes. Again, I really appreciate how you clearly you painted the picture there.

I definitely wanted to retain the original pipes, but, was just curious what others thought. I think I will search around locally for someone who might be able to do the repair. I'm not daunted about trying it, but, fearful if I don't do it the best way possible, I might make it worse or damage/ruin the pipe itself.

If anyone knows a reputable mechanic who might be able to work on my situation, I'd love to find out about them. I'm in Bolton, MA about an hour due west of Boston.

Thanks again for your considerate delivery and wealth of information.

Jay

[mack]

For what

it's worth. I bought a set of stock standard pipes off Ebay couple years ago as they sure looked good in the photo's. Paid $80 bucks for the pair. Thought it was a steal at the time. Well when they arrived I was very disappointed. Could push my finger through the side walls. Anyway. The guy that did the gold for my LH also does all the copper repair work on the roofs in Ottawa. Anyway I took these pipes to him with some other chrome pieces I wanted done for the E. What he did was cut the pipes in half length wise. Separated bottom from top and cut out all the rotten stuff and crafted in copper. Basicly restored them from the inside out. Then welded them back together and rechromed them. They look brand new now. I don't have the Bike ready to test them but if they perform half as good as they look, I'll be pleased. Best part is they will never rust out again.

[jpilk99]

Thanks!

Hi Mack,

That's very interesting - I hope they sound as great as they look. I actually thought about the viability of having the exhaust pipe cut in half VERTICALLY at the point/area where I'm pretty sure the looseness is. Youre story, while ...scarier, is certainly more complete.

Let me know how you make out. Thanks again.

Jay

[cajun31]

Mack

What did having those pipes repaired run you? Neighborhood price? I have seen several sets over time on Ebay that look good but generally have bad spots here or there but if the cost was right for repair they might be worth it. Just curious.

jpilk99.... good call on getting those pipes repaired. Wish you much success.

[skids]

(snip)What he did was cut the pipes in half length wise. Separated bottom from top and cut out all the rotten stuff and crafted in copper. Basicly restored them from the inside out. Then welded them back together and rechromed them. They look brand new now. I don't have the Bike ready to test them but if they perform half as good as they look, I'll be pleased. Best part is they will never rust out again.

That is a very interesting concept! Did he do baffles also?

[mack]

Yes

He redid all the baffle and they are double walled again with a solid brass tube running the lenght. He had them for almostb 18 months , working on them when he could while maintaining the work load of his shop and the government contract for the roofs etc. He is a very meticulous guy and thats why I like using him. So am I! We speak the same language. At the time he tried to talk me out of it explaining thow time consuming it would be but I said that it wasn't an option. I needed these pipes like new and there was no replacement. I'd tell the world if he f..ked them up. So he took his time and the result is outstanding. I can't get over how deeper the chrome looks in comparison to the, handle bars or the factory chrome.


These are poor pictures taken indoors. To get the full effect I'd have to shoot them out doors. Bottom line was it cost me $2650.00 can. for everything you see plus the lift bar, rear fender and the luggage rack.

[cajun31]

awesome parts

Don't know how many of us would be able to drop that kind of money on a bike that might not be worth the investment but those parts look better then factory new. Looking forward to seeing the finished bike pics.