broken header bolt & muffler cut off question

[downtimeinc]

Hi Guys - I'm relatively new here and hoping someone can point me in the right direction...I'm in the process of installing some 16" shorty slashcuts on an 82 exhaust. While loosening the header bolts i managed to break one off - its not sheared, but busted off at the nut. Am I correct in thinking these stud bolts thread out of the case or do i have a big problem on my hands? I also have a 79 that i'm working on, but it's a ways off gettin on the road so i'm not adverse to borrowing a few parts off that one to keep the daily rider going for now - are the 79 headers/header bolts compatible with the 82?

The 79 also has bolt on mufflers, which would temporarily solve my issue with cutting the pipes on the 82 at the right point in order to fit the slash cuts...I cut one of them off but the inner pipe extends too far to fit the shorties on as it is larger in diameter than the interior wall of the new slip ons - will cutting this inner pipe have adverse affects? I've attached a couple pics for reference. Thanks in advance for any advice.

 

[Specdog]

I will address the broken stud issue. First off you have lots of stud remaining so that is a good thing. From here on in when trying to remove the stud DO NOT use too much force as that could break off the stud flush or counterflush and that will bring you much more grief. There are several back yard methods to removing the stud, but I recommend you take the bike to a welder and have him weld a nut onto the protruding stud. The heat generated from the electric welder is the trick to removing this easily. The heat will transfer through the stud and surrounding aluminum and break free the corrosion that has frozen the stud in place. A good tip here is to apply wax from a candle just after welding. The wax will transfer up the stud and act as a lubricant. The welded on nut also gives you the perfect leverage point. Remember use prudent force. The first twist of your wrench should be to tighten the stud, followed by a loosening twist using very small increments alternating back and forth until the stubborn stud becomes easy to remove.

 

[downtimeinc]

Thanks Specdog - Appreciate the tips. I'll give that a try

 

[MechNewb]

The stock headers are dual walled, so youll need to get a reducer to fit the inner pipe and the muffler. Then youll want to cut that inner pipe back a bit to fit the muffler over.

 

[downtimeinc]

am I right in assuming you would crank the stud clockwise to remove?

 

[Buccaneer]

Hi downtimeinc,

I recently put new silencers on my XS400SE so I may be able to help a bit but I am certainly no expert!

I posted some notes here after getting some useful info from the guys at the sister site:
http://www.xs650.com/forum/showthread.php?t=27956
You may find some useful dimensions here but nothing you can't measure easily enough once you've cut up the old exhaust.

Regarding cutting off the inner, my GUESS is that doing that makes it more likely that re-jetting the carbs will be necessary, especially if the silencers have significantly lower airflow resistance than the original ones.


cheers,

Martin.

 

[downtimeinc]

Thanks guys - anybody know where you can get new header studs by any chance, or what size they are? may try to find something at the hardware/auto store - if i can get one out without breaking it lol.

 

[downtimeinc]

bit of an update...took the bike in to the local machine shop to have them weld nuts onto the broken header bolts (managed to shear another one off) and they were unable to budge them. They told me to bring the cylinder head in and they could mill them out and rethread, so i'm in the process of dismantling for engine removal. Before pulling the whole engine, I thought i'd ask if it is possible to remove the head without removing the whole engine from the frame...has anyone tried this or do i need to pull the engine?

 

[cope849]

You can pull the head well the motors in the frame.would it be easier to just take the whole bike instead of pulling the motor apart.

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[MrStubb]

Hi Downtime I had taken my exhaust off with no trauma but from previous experience a good penetrating oil judicious use of heat and patience would be your best friend. For your muffler issue I used a pipe cutter and went only enough to cut the outer pipe. It takes a little bit of patience. Make sure you don't go too far and go thru both walls. I installed a regular muffler but do need to cut the inner pipe down about 2" to get a better fit.

 

[MrStubb]

Just remembered something for your studs. There is a tool for this you may find at a well equipped auto parts store. A stud extractor may fit in the space you have but you'll still need mild heat and penetrating oil. Not to mention Patience Patience Patience. Oh did I mention Patience!!!

 

[Specdog]

Just remembered something for your studs. There is a tool for this you may find at a well equipped auto parts store. A stud extractor may fit in the space you have but you'll still need mild heat and penetrating oil. Not to mention Patience Patience Patience. Oh did I mention Patience!!!

No, I believe he is beyond that stage. If you can't budge them with arc welding, then surely lesser methods will not work. I think he is done here, so the head has to be removed and brought to a machine shop where they can do their magic and cut out the stud.

 

[downtimeinc]

Well I went ahead and yanked the engine out...good learning experience and definitely a lesson in patience given that I don't think any of these bolts have been loosened since it was originally put together. That and a engine in frame engine paint job that a previous owner had applied equaled some tough nuts to crack...fortunately no more broken bolts. Tomorrow I start on disassembling the cylinder head - been through the manual a few times and researched it as much as possible here, so it's wrenchin' baggin and taggin time.

my only concern with getting the studs machined out is figuring out the replacement bolts. Does anyone know if the 650 studs are larger than the 400s? Was thinking if they were I could try to get them to size/thread the new holes to match...