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Discussion Starter · #1 ·
So for anyone installing exhausts themselves...please do not over tighten the bolts where the exhaust mounts up to the engine! I have learned the very hard way.

First off.. I tightened them so hard when I first installed my m4 slip on that the black flanges around the stock headers bent. They bent so much that we had to cut them off with a Dremel. Then, when I went to install the akrapovic carbon.. I discovered I tightened the stock headers so hard that I managed to bend the actual studs in the motor! so i removed the old studs and waited for a while to get new ones

Now for the worst part...I began installing the new studs, first in the exhaust port to the far left of the engine if standing in front of the motor. I got one in fine. As i was installing the second one on the same exhaust port, i cracked the actual hole in the motor where the stud goes causing the stud insert to break off the motor.

not knowing how the hell im going to fix that without actually spending the money to buy a new engine case, I just put the headers on and tightened them down with one stud missing...tightened them down to proper torque specs with a torque wrench that is.

So i started the bike and it sounds fine..aside from a second of loud ticking at the very start...i have a manual CCT so its not that..i assume the ticking is from exhaust gases escaping for a brief second

Problem i think Im gonna have now is the engine case being weak right there and further cracking...dont really want to shell out the 2k its gonna cost to buy a new engine case and have it installed..literally just feel like trading the bike in and getting something else cause i literally ****ed this bike by doing that

if anyone has any suggestions it would be greatly appreciated.
 

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Wow. I feel for yah man. I have over tightened things in the past. It is a scary feeling, not knowing what to do. I wish I had some advice for you. All I can do is wish you luck. Like you said maybe the best thing to do is trade in and hope they don't notice it.
 

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You said that you were buying a torque wrench, did you?

I know you feel compelled to trade it in, and not mention the problem, but... Maybe its me... That seems dishonest.

If your brother bought the bike from you, would you tell him? I dont see the difference.

This really sucks, but a proper tool and proper technique would have solved this.

This isn't the dealers burden to bear. This is what I refer to as stupid tax. We all pay it. And it is only ours to pay.
 

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Yikes... sorry to hear this.
Appreciate your sharing. Reminder for all of us.
Hope this is manageable.
 

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You said that you were buying a torque wrench, did you?

I know you feel compelled to trade it in, and not mention the problem, but... Maybe its me... That seems dishonest.

If your brother bought the bike from you, would you tell him? I dont see the difference.

This really sucks, but a proper tool and proper technique would have solved this.

This isn't the dealers burden to bear. This is what I refer to as stupid tax. We all pay it. And it is only ours to pay.
I don't feel that not mentioning the problem is dishonest. If they ask if anything is wrong with the bike and you affirmatively lie, that is another story. But failing to mention it is Cavet Emptor. Especially when we are talking about a dealership. If they fail to see the problem that is on them. There is not duty to disclose here.
 

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We all learn the hard way. Better to leave exhaust nuts on the loose side and re torque once in awhile if you don't have a torque wrench. Replacing a lost nut is a hell of a lot cheaper.

I do agree that if you are going to trade it into a dealer it is not your responsibility to tell them anything. If they take it in as is without a check of areas known for issues like exhaust connections then they have no one but themselfs to blame. If they resell it in the condition it is in then they are the ones who should have made it right. Maybe you were planning on telling them the stud is broken off at time of trade in? Now selling it outright to someone and not telling them that there is an issue I would consider very shady, but then again I wouldn't buy any new or second hand bike without looking it over really well. A dealer is not going to be out much if they have to fix something like that. They have the tools, parts, and I would hope the know how to fix that. So I wouldn't have a problem trading it in without saying anything if they don't ask.
 

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If you only overtightened the stud and the damage is localized to the head, you can replace the head and leave the rest of the engine. And a quick search at Honda Motorcycle Parts ? OEM, Aftermarket and Vintage Parts Online \| Service Honda Motorcycles returns a price of about $573. In the grand scheme of things, that head is a bargain! Of course, add in some money for oil, coolant, head gaskets, copper crush gaskets, etc.

Alternatively, the damage may able to be repaired...weld repair and possible some other alternatives. Picture?
 

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Better to leave exhaust nuts on the loose side and re torque once in awhile if you don't have a torque wrench. Replacing a lost nut is a hell of a lot cheaper.
Even that is no excuse when decent torque wrenches can be had for around $20. If you can't afford a $20 torque wrench, you can't afford a motorcycle. Or anything mechanical for that matter.
 

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If you know of a very good, experienced TIG weldor, they could possibly fix it. The first part of the procedure would be to stop drill the furthest point of the crack, then to grind the remaining crack all the way out to base metal prior to welding. Make absolutely certain that none of the particles of metal can get inside the exhaust port. The weld filler metal must be compatible with the base metal. If they use the wrong type of filler material, it will probably crack again. You or the welder will have to obtain that information (probably from Yamaha). If the crack originates in a threaded hole, that would have to be retapped and checked for proper sizing with the new stud. This would be the least expensive fix, if you find a meticulous, expert weldor with references to back it up.

A more expensive alternative would be the same type of repair procedure handled by a good Yamaha service center. They may feel the need to partially disassemble and remove the cylinders for the welding. If they're a good dealership, they'll back up the repair.

One other thing I would strongly urge you to do is buy yourself a good torque wrench and use it on everything.

If you sell or trade in the bike without the repair, please be up front about the crack. If you have a repair estimate, you may be able to negotiate a reasonable selling price to cut part of your loss.

Good luck.
 

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First off, hope you learned how to use the proper tools from this.

We all make mistakes but please learn from them. This one is going to be expensive.

Hamfisted mechanics ruin all sorts of equipment and tools!

I do not recommend riding the bike with only one exhaust stud holding on one of the header pipes. You will likely damage the remaining stud and ruin the exhaust valves on the cylinder when the air leaks into the exhaust port. Air will leak into the exhaust port through the poor seal and that will damage the engine.

As to repairing your engine, you probably have 2 choices:

1) replace the cylinder head (not the engine cases) as the cylinder head is where the exhaust connects to the engine.

This is not a job you should attempt.

Let a qualified mechanic do it because timing the cams and proper torque sequence and amounts for removal and installation are of paramount importance or you can destroy the entire engine.

2) repair your cylinder head. You MIGHT be able to repair the cylinder head without removing it first. Your best bet is to call around to some machine shops that specialize in head repairs and have them look at it. They may be able to weld up the damage you made and then drill and tap a new hole for the stud. A good machine shop should be able to do the repair for a couple hundred $ or so, if it can be repaired.

If they can't repair cylinder head on the bike, it is possible they can repair it off the bike but that means removing the cylinder head and frankly with your "expertise" as demonstrated by getting yourself into this mess, I do not recommend removing and installing the cylinder head yourself.

One other thing: if you are going to work on your bike, please do yourself and your bike a favor and get a shop manual and read what is required and use the correct tools so you don't mess up bike further.
 
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You aren't legally obligated to tell the dealer of a problem, but morally, I would be.

Think of this. You trade it in, don't mention it, dealer sells it without noticing... Now a completely innocent person is stuck with your poor mechanical ability, with no recourse, sold as is, used...

I'd feel sorry for that guy, not yourself...

I'd don't subscribe to not taking full responsibility for my own mistakes, and passing it off, simply because I can. Just because you can, doesn't mean you should, and there is still RIGHT and WRONG... Those are absolutes, to me anyhow.

If my own son did this, I tell him to buy a service manual and torque wrench next time, because it's infinitely less costly than what he is about to pay to fix it. I'd slap him if he even considered passing it off as anything but mechanically flawed.
 

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^ +1 Just because a dealer has more money than you doesn't make it okay to stick them with the responsibility for your ineptness. Full disclosure is the right way to go.

The repair route would be my first choice. Look for a certified welder as they can better match up alloys for welding and are proven to weld properly. A machine shop with a certified welder would be a good choice. Of course certification is no guarantee of good work, it just means they know how to do good work. Good luck.
 

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Even that is no excuse when decent torque wrenches can be had for around $20. If you can't afford a $20 torque wrench, you can't afford a motorcycle. Or anything mechanical for that matter.
I would reword that. If you can't afford the proper tools or don't want to buy them don't work on your bike. Many people own mechanical things but choose to have someone else work on them. In this case that probably would have been a smart alternative.
 

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Feels like a religious meeting here.
Somebody open the windows!!! :p

(OP...go to your room!)
 

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Discussion Starter · #18 ·
appreciate all the responses and advice everyone...I should have mentioned in the OP that i would tell the dealer about this issue..i take full blame for this and like the title says..its a hard lesson learned..whatever money they would give me for the bike, the rest would have to be financed into the price of the next bike..IF i go that route..BUT..here is a pic of the damage..



It looks like just surface damage and it didnt go too deep into the motor

and i just drove it for 30 mins with no problems and no weird sounds...with the akra carbon and vcyclenut tune the bike pulls incredibly hard..you would never know it had this issue cause it doesnt affect anything yet..like i said, the two other header ports are torqued down properly and the far left one has one bolt torqued down properly

another thing i may do is epoxy the piece that fell off back onto the motor then take a regular bolt and bolt the flange onto it...like i said its not leaking now so i would just be doing that so it doesnt look damaged..would still tell the dealer about the issue

looking at the damage again it doesnt look as deep as i originally thought and dont see it getting any worse..im gonna keep riding it and whatever happens happens i guess

I did buy a torque wrench and ive been happily using it lol
 

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I'd like to clarify my last response regarding weld repair. We're all just guessing without seeing the crack. Even so, weld repair isn't without consequence. From an engineering point of view, if you were to do this correctly you'd first need to establish the extent of the crack. This can be done visually, but that only tells part of the story. You might need to resort to dye penetrant or radiographic testing. If both ends of the crack (root and extent) are found and determined to be in a safe location, you can terminate the weld with a properly drilled relief at the end(s). This is what stops the crack from propagating.

If this were a high dollar part, some fancy pants engineer would assess the location from a structural and thermal stress/fatigue perspective to figure out how significant the damage is. Depending on the crack size, weld repair may or may not be required. It's a case by case basis, but weld repair is usually a guarantee for something like this. Given your/our limited resources, welding would be recommended. That said, the area of the head would have to be prepped which means disassembling, dressing, etc. A poor weld repair procedure could cause more damage to the vehicle than you started with, so there is some inherent risk...be warned and get educated if you go this route.

Given how inexpensive the head is, the safest recourse in my mind is to buy another head and swap it out. You're talking about ~$650 in parts plus labor.
 

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appreciate all the responses and advice everyone...I should have mentioned in the OP that i would tell the dealer about this issue..i take full blame for this and like the title says..its a hard lesson learned..whatever money they would give me for the bike, the rest would have to be financed into the price of the next bike..IF i go that route..BUT..here is a pic of the damage..



It looks like just surface damage and it didnt go too deep into the motor

and i just drove it for 30 mins with no problems and no weird sounds...with the akra carbon and vcyclenut tune the bike pulls incredibly hard..you would never know it had this issue cause it doesnt affect anything yet..like i said, the two other header ports are torqued down properly and the far left one has one bolt torqued down properly

another thing i may do is epoxy the piece that fell off back onto the motor then take a regular bolt and bolt the flange onto it...like i said its not leaking now so i would just be doing that so it doesnt look damaged..would still tell the dealer about the issue

looking at the damage again it doesnt look as deep as i originally thought and dont see it getting any worse..im gonna keep riding it and whatever happens happens i guess

I did buy a torque wrench and ive been happily using it lol
Well, I wouldn't call that a crack! More like a missing piece...I wouldn't weld this. You'll need finish machining to clean up the port and even then, there are no guarantees that the heat affected zone from the welding didn't warp the head, weaken some critical part of the casting, etc.

You can try epoxying the piece back on, but the most commonly available high temp epoxy I'm aware of is rated to 500F. Not sure how that will work there.

Personally, I'm sticking with buy a new head. Anything else is a science experiment.
 
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