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Discussion Starter #1
So, when I bought tricky she was in good shape, the previous owner was a wrench turner and only sold it because he had 4 other bikes to insure. A couple months after, I suffered the broken bolt issue on the right side exhaust. Both exhaust attachment bolts snapped off at the block and needed extraction. I managed to extract one of them, but I ended up re-tapping the other.

I did not do such a great job and the angle of the re-tapped one was a little off (about 5 degrees) so once the stud was in, I had to bend it a little to get it in the flange. I think this may have contributed to it's next break.

A month or two later, the bolts snapped again. Fortunately, this time, I was able to extract them with pliers. But I'm thinking that the factory studs are not the best option. However, I also didn't have a torque wrench at the time, so I may have over or under tightened.

So, this time, I
1) Bought a click type torque wrench at Harbor Freight.
2) used an 8.8 high carbon all thread instead of the missing bolt.
3) used regular nuts, torqued the inner one, then tightened the outer one to the inner.

First question: Has anyone tried a replacement for the studs? How did it work?
Next: Do I need to re-torque these nuts after the copper gasket has had a chance to settle in?
Third: should I have used a gasket sealer or something along with the copper ring?
 

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You should check the torque on the nuts after a couple of heat cycles. You don't need gasket sealer for the copper seals.
 

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taking my rebel 450 for a garage to remove a broken stud because it is on of the inner ones the frame stops the getting the right angle to drill at so he is taking engine out of frame.I was also told by him that he uses left hand drill bits as this some times helps with the broken stud extracting itself during the drilling process.He told me he does not like to use easy outs because if they break you are in a worse state as there is no drilling these .So fingers crossed all will be ok he told me worse thing that could happen would be the use of a helli coil
 

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that's why the fella wont use them and uses left hand drills to drill out the studs being drilled left handed can help because the force used is loosening the stud where as the normal right hand drill the force tightens it .With exstraction you need all the help you can get lol
 

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I've heard of broken bolts coming out with just the left hand drill bits. Never needed one, but if I do, will be sure to get one! Penetrating fluid can also help free the studs.
 

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been spraying that on it all week will do every day till fri when trailering it in to garage
just got my replacement forks and other bits from the states
 

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The only one I ever extracted came out quite easily with a properly sized EZ out. The stump was not very tight at all in the head.
The key to NOT breaking a stud extractor is to use a good quality one that is big enough. The hole in the stump has to be at least half the diameter of the stud or more if possible.
It is impossible to drill out a broken drill bit as well as a broken stud extractor. That's why I used brand new drill bits and started with a smaller pilot hole drilled from a center punched locator mark.
 

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Discussion Starter #11
So, I'm kinda playing with a theory here. What would happen if you were to take off the exhaust pipes completely? Obviously, the bike would be louder, but what other performance issues could you expect other than bits of hot lava jetting out the front of the bike? Reduced performance? Milage? etc?
 

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And yes, reduced performance as well. Not sure about fuel economy, since I've never done this (and never would) but assume it would suffer too.
 

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The mass of gasses flowing out of a closed exhaust system has momentum which plays a part in scavenging the last bit of exhaust out of the cylinder as the exhaust valve closes and loading the next fuel charge into the cylinder during the valve overlap period (both valves are open). Without a long enough exhaust pipe to keep the gases moving out of the engine, cold air will suck back through the exhaust valve and thermally shock it.

Obviously cold air mixing with the new fuel charge from the carb will result in a very lean mix which will have a tendency to burn valves or hole a piston.
 

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Discussion Starter #15
And yes, reduced performance as well. Not sure about fuel economy, since I've never done this (and never would) but assume it would suffer too.
Okay, yeah, Like running open headers on a race car, not enough back pressure and your performance drops.

In another thread, I hypothesized that a tank of premium netted me a bunch of bonuses like better milage, quieter running, and more power. My current hypothesis is that after "fixing" my exhaust the first time, I messed up the job somehow (improper alignment or torque are my first guesses) leaving a small gap. This reduced the power and milage. Eventually the problem corrected itself, the muffler seated properly, and performance jumped up. When the exhaust pin broke a second time, I was able to hobble it together with a makeshift gasket that I'm guessing didn't have a proper seal. IE that power didn't last.

Last night I took her on a trip with (finally) everything together, parts from the dealer, and properly torqued. First part of the journey was on the same tank of gas I'd been running on before the replacement, so I know the bump in power wasn't the gas. But, like that other time, I had a quiet bike, good power, and fair milage.

So my hypothesis is that I bought the bike with small problem in the exhaust, got used to the noise level, lived with it until the second pin broke. I extracted those pins, tapped a new hole, replaced them, but didn't get the tube seated properly. So, by performance was the same as what I was used to. THEN, I buy the tank of gas and coincidentally, the muffler seats properly (or whatever) and suddenly, I'm getting "normal" performance. This doesn't last because the new repair wasn't torqued properly and breaks again, and performance drops to what I'm used to. It stays that way until the new parts and proper use of a torque wrench gets everything seated as it should be.

May have to check the valves, and the piston it sounds like....
 

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Wow... IMO you are seriously overthinking this. The torque wrench is only to avoid stretching the new studs until they break, not to "seat" the exhaust.. 7 foot pounds doesn't feel like much on the end of a wrench.
I also doubt that a small exhaust leak would have any seat of the pants detectable effect on performance..
 

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remember on re-fitting a exhaust to use new two header gasket rings these compress to stop leaks being soft .got mine waiting to use after getting broken stud out also the joining gasket for the left and right exhaust together.
 

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Just as a matter of interest, Of all the exhaust systems I have removed and replaced, I have never bothered replacing the soft copper gasket Usually it stays in place in the head, and re- installing the header will result in a satisfactory, if not absolutely tight seal. If the gasket comes out, you can resoften and "swell" it again by heating red hot with a torch and plunging it into water.
If you can't hear a "ticking" noise, it's not leaking enough to worry about.
 

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It seems to me that if you haven't adjusted the valves that would be a good place to start. If you are concerned that you have done any serious damage a compression test should tell the tale. Most likely your favorite auto mechanic could do that for you if you don't have a bike shop you trust.
 
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