| Author | Message | ||
     Yohinan |
Does anyone here know what grade or psi tensile strength the factory HD exhaust studs are that our bikes use? Seems these break all too often on the tubers and any slight drop of the XB's cause these studs to break over time. I am wondering if these new ones I got will hold up better if my XB happens to get dropped again, not intentionally of course. Thanks for the help. John | ||
| Blake |
I've yet to break one and I check and tighten the header nuts frequently. Are you talking about the studs clamping the header to the cylinder head? If so, not sure you have any alternatives. Pretty sure those studs are pretty high grade material. But to answer your question... no, I don't know for sure what grade the studs are. If I had to guess, I'd say that they are probably grade 5, possibly grade 8. | ||
| Jackbequick |
The tensile strength on Grade 5 and Grade 8 bolts is 120,000 PSI and 150,000 PSI respectively. Those numbers should apply to studs also. Part of the problem on exhaust manifold studs is that they are subjected to repeated heating and cooling cycles. That tends to make ferrous materials a little crystalline and weaker over time. Probably the best you can do is to find good quality Grade 8 studs (rolled thread studs are better than cut threads). Exhaust systems are long and heavy and can put a lot of strain on the studs when the exhaust system mounts get loose or in accidents that hammer the studs. Thats been going on with bikes ever since I can remember. Jack | ||
| Yohinan |
Yes I am talking about the studs that go into the heads that are used to tighten down the headers. I am thinking about going as far as having a few tested to find out truly their grade in a new state. I bought some new ones and was going to put them on this weekend but I said screw it. I got some stainless ones that are better than grade 8. They are rated at 170,000 PSI. I will see how these hold up and after I find out what the originals are (strength wise)I may have a good replacement for those that want peace of mind. The XB guys, what I have, most likely wont go this far as our failures seem to be few and far between but the tubers I know have lots of problems with this. I will report back with my findings. That is of course as long as this procedure does not cost too much. Also the studs are not all that cheap compared to the stockers but it's worth it to me to save myself from drilling studs out of heads every so often. Maybe someone here actually knows what strength the stock studs are and can save me some money. Anyway I will stop typing as I might go on too long. Thanks again. John | ||
| Blake |
I've been riding Buells and all tube framed Buells since 1998. I've never suffered an exhaust stud failure. And I've hopped up and raced the things too. The numbers Jack posted above sound about right to me. Here's the problem. The fatigue strength of 170,00 psi SS stud will not be much if any better than that of the grade 5 or grade 8 steel studs. It is the fatigue strength that is governing the failures of most exhaust stud failures. Not sure that holds in your case of dropping the bike, but for most that is definitely the case. I suggest you try adding some bar-end, and front and rear axles sliders and frame sliders to keep your header from impacting the ground. Address the cause, not the symptom. So most importantly... don't drop your bike.  | ||
| Yohinan |
Blake, I understand you are one of the fortunate ones that has not suffered a broken stud on a tuber. However, are you saying this is not a problem with them? The reason I ask is I have read many many posts and websites that seem to think tubers break studs on more than a rare occasion. In regards to the studs that I have purchased they are not made for general use for whatever you want. They are specifically made for exhausts and to take the heat cycles and corrosion that most studs endure. And I am not sure about you but my personal opinion about these studs HD/Buell uses is they suck. If a side effect of dropping your bike, mind you while not driving just learning to drive slowly letting the clutch in and out, and dropping it causes the stud to break their is a problem. At least in my personal opinion, mind you I am not saying this is a problem with anyone else, that is •••• poor quality. Yes I can see cosmetic items being damaged and headers, handlebars, etc.. but a stud coming out of the head snapping off is an issue. Even if it doesnt happen right away. I mean the stud does not even take a direct impact. What if when you dropped your bike you had to replace all your hardware, would it be a problem then? I guess I expect a lot more out of a stud. It is not a wear and tear item in my opinion say like internal engine parts that are moving, etc.. I realize the numbers for a grade 5 and a grade 8 have a certain number but it seems no one knows what the stock grades are for our studs. All we have are guesses at this point. And I already have bar-ends, front and rear sliders and pucks installed. And yes they were all on the bike when it was dropped so that obviously does no good for taking some of the damage away from the studs. John | ||
| Blake |
Don't drop your bike. If you do, apparently the exhaust studs may break. If you suffer broken exhaust studs, there are tools available to facilitate removal/replacement. Motorcycles are not idiot proof. When you drop them, stuff will break. Exhaust stud failures on older model Buells were not unheard of, but they were far from common. I am not one of "the fortunate ones", I am one of the vast majority who have not suffered such a failure. In most cases the failures are attributable to aftermarket exhaust systems that are not adequately contrained to the prevent excessive vibration. Personally, given the choice, I'd rather suffer a broken exhaust stud than a ruined header. Don't drop your bike. | ||
| Reepicheep |
Tuber studs were not breaking because tuber studs were bad, tuber studs were breaking because tuber front exhaust mount bushings were bad. Use the new Y mount, install the exhaust carefully preventing tension anywhere, make sure the nuts don't back off the studs, and they will last forever. | ||
| Blake |
Guess what happens when you drop a Ducati 749. You damage a $1K+ painted fuel tank. Still see fit to gripe about a $2 exhaust stud? | ||
| Blake |
I'm still running the original front header mount bracket on my '97 Cyclone. Not a single broken exhaust header stud. I have replaced them once though at around 20K miles during a street to race swap of the header. | ||
| Jackbequick |
There are a number of companies selling improved fasteners for racing and other high stress applications. Here is a page with a good general discussion of bolt strength. In the table comparing bolt strengths, ARP, SPS, and MS14181, refer to products by makers of higher strength products. One bike that I had in the past was regularly losing nuts/breaking studs on the exhaust. I finally solved that by double nutting the studs. I tightened the regular nut to the torque spec, placed a thinner locking nut over the regular nut, and locked them together. That solved the problem. Part of the issue on that bike was the need for frequent retightening and even overtightening out of frustration. The double nutting turned out to be a good long term solution. Jack | ||
| CJXB |
Dang, wrong kind of studs !!  | ||
| Yohinan |
Guess no one here sees my point. You are all missing it. If you all think it's ok for a stud to break this easily then thats cool for you. I guess you have come to expect this anomaly from your bikes. Those that have had it happen anyway. John | ||
| Samc |
I want the first thing to break to be cheap and easy to replace; like a fuse. | ||
| Yohinan |
Well Sam I will agree with you on one point. The stud is in fact cheap to replace but I would not necessarily call it easy, or should I say quick. I would say it might be a little easier on a tube frame than an XB but not fast by any means. I am going to do a write up on my way of getting out broken bolts/studs that I have never seen anyone else do yet but, I am sure others do it this way just never heard of anyone actually doing it. It doesn't involve using easy outs or the Jim's tool. If I can find my digital camera by this weekend I will take pics of the process so maybe it will make things a little easier to understand as sometimes my words seem to confuse others. John | ||
| Samc |
I'll be very interested in that. | ||
| Rocketman |
John, whether you choose to believe it or not Reep hit the nail on the head. Tube framers break exhaust studs because some people that fit them pay little attention to getting the whole system to fit without straining the studs and the mounts. As Reep said, you need the 'Y' shaped front mount otherwise you're pissing in the wind to start with. I can't speak for those that have run with after market systems but I reckon Blake's right about vibration. My S1W has the Pro-Series set-up and I've broke a few studs myself but that was before the 'Y' bracket was used. That bracket has 'soft' bushings in it and it allows the system to float into its natural position once the motors run a few miles and settled down. The old bracket was a piece of shite and left no movement/adjustment once tightened. Eventually the old metal bracket would break. Here's another good tip for y'all that'll mean you never need tighten those studs again. After all if you don't f*ck with 'em they're bound to last longer. Once those stud nuts are tight use a high temp sealant on the nuts/studs/threads and they won't ever come loose so you'll never need to tighten them again. Rocket | ||
| Bigdaddy |
Good advice all the way up. Another little not-so-secret to success after getting *everything* nut-flushed up spend the extra $2.00 on 4 extra nuts and double nut the studs. Ironhead's will crack an anvil, given enough time, but they won't back-off a double nut.....YMMV, but I doubt it. G2 | ||
| Blake |
I have always had double nuts. ![: ]](http://www.badweatherbikers.com/buell/clipart/proud.gif) | ||
| Blake |
"If you all think it's ok for a stud to break this easily then thats cool for you. " If you think that it is that easy or common to drop your bike, then that's cool for you. In all my days of street bike riding starting in 1980, I have yet to drop a bike as you describe. Address the cause, not the symptom. So most importantly... don't drop your bike. Looks to me like you are searching for something to gripe about. How about you learn to not drop your bike? | ||
| Bomber |
double nutting the header mounting hardware can also cause problems -- while the nuts may no longer back off on their own, when the time comes to drop the system (like, o, I dunno, for a gasket change?), double nutting the header mounting studs CAN result in backing the stud outa the head, while trying to remove the first nut -- the studs and nuts, as was pointed out by a number of alert badwebbers, undergo lots of heating/cooling cycles -- this has the unfortunate affect of rendering even stain-RESISTANT steel (no such thing as truly stainless steel) much less resistant -- things have a tendancy to corrode together, mebbe just a little, but the bottom line affect is that some number of your studs may back out with that first nut (some number can equal 3 out of 4, and you don't have to ask how I know, do ya?) while not every tuber with old style exhuast mounts ate studs,enough did that the factory gened up the replacement, Y style mount -- lots of other folks replicated the S2 (?) additional header mount to further stabilize the system -- that, coupled with the mounting tips given by Reep, Rocket, and others about letting the system find it's own place during installation (don't force anything into alignement, not even a little bit!) will greatly reduce, if not eliminate, your tuber's desire for a breakfast of exhaust mounting hardware btw, my Y2K MaDeuece had quite an appetite for exhaust studs before it went down on the right side for the first time -- while stressing the system that way can certainly add to the the broken stud problem, it ain't the only way that said, not dropping your bike sounds like pretty good advice -- think I'll give it a try! ;-} | ||
| Reepicheep |
I did the double nutting initially to keep the nuts from backing off, but based on discussions with Aaron he convinced me that all that will do is break studs if the root problem persists. The Y mount, and careful install, was the solution to the root problem on my bike. That being said, I did leave the double nuts on after that, not as a "keep it from backing off" thing, but as a "easier to inspect" thing. With single nuts, it was difficult to see if the nut was still there with a quick glance on a pre ride inspection. With double nuts, I could (and did) check it with a glance before most rides. | ||
| Mikej |
I must be doing something wrong, still have the stock original hangers on both bikes, still haven't broke an exhaust stud yet, using single nuts, don't think I've lost a nut yet either. Got a Y-mount in the garage I haven't installed. Did break the hanger tabs off a WileyCo exhaust so have the stock can back on the M2 for some time now. I'll try harder. | ||
| Bomber |
throw that darned scoot against the planet repeated, Mike -- you catch on | ||
| Mikej |
Nah, I'll pass, that just gets my pants all dirty and scuffs my shoes up. I did once do a two-wheel drift on the M2 one year at SlimeyCrud, hit an island of gravel in a corner in the middle of a three-way intersection, rode it out and kept going, interesting intersections out that way. Be carefull out there and keep the handlebars above the tires. I would say keep the shiney side up, but my bike's not too shiney these days. | ||
| Yohinan |
Blake, stop opening your mouth and inserting your foot. Your always the one to point out things such as this. Please tell me where in any of my posts that "I" stated that "I" dropped my bike? You wont find it. I didnt drop my bike a friend of mine did. I am glad to see that you have never dropped a bike while street riding. I must say I guarantee you that you drive more conservatively on the street than I do then and that is a fact I am sure of (I base that off of your age and dont get offended by that it is a fact of life. Also based off of what I do for a living) . Yes I noticed you said in all of your days riding you havent dropped a bike as "I have described". Well neither have I. And your right I am looking for something to gripe about because this is a problem as far as I am concerned. Is it a problem for you? No as you have stated it is not so please refrain from reading this post any further as you have no concerns with it. Thank you and have a good day. John | ||
| Rocketman |
Speaking of dropping bikes. I was at Squires Coffee Bar two Wednesday's back and it was getting late and most bikers had left, thank f**k. Not one to miss an opportunity to showboat I launched the front wheel into the air for a little wheelie upon leaving. Usually there's no room in the bike park coz it's always jammed but as it was late on..........................you get the picture. There wasn't a great deal of length to hoist the front wheel up high or for long so just before I ran out of road I brought her down swiftly and grabbed the front brake. Little bit of gravel, too much pressure on the right lever, a little waggle of the bars and there I was skating down the road on my arse. Those headers take some beating as crash bungs I can tell ya, and never a broken stud would you believe. Goofed the K&N Force filter though and a two week old pair of button fly Levi's. I thought Levi's were expensive until I priced up one of those Force jobbies. Hell it's only a bloody K&N. Anyway a good group of fellow greebo's came to my assistance afterward and man did they freekin laugh as they ripped the crap outta me. Well the joke was on me after all but the Buell got high praise indeed for crashing so well and only getting a scratch. I love bikes that crash cheap!!! Rocket | ||
| Yohinan |
Rocket, Actually the stud will not break right away. Since starting this thread I have received a few emails from other XB owners that have experienced the same thing. The stud does not break on the initial impact. It weakens it substantially and a week or month or more down the road is when it will just snap off when you least expect. I have not heard of or gotten any emails from XB owners that have had a stud break with out the bike first being crashed or dropped. That is obviously what is causing these to break. I got my new studs and locking nuts that I ordered from ARP today. They are a bit different looking compared to the stockers. The end that actually goes into the head is a bit shorter and the end that the header bracket is tightened to has a bullet nose on the end. Also this end is a little longer than the stock stud. I will let you know how the install goes this weekend and I will also have to do my write up of how I remove broken studs. John | ||
| Reepicheep |
Glad you are OK rocket... I saw another perfect looking S1 highside (low speed) at a battletrax (it was off track, screwing around in the parking lot). It broke my heart to watch the thing bounce, but it came out very well (minus forcewinder). | ||
| Henrik |
I was skating down the road on my arse. Thankfully we have a bit of padding on which to skate - eh? I understand the frustration with stuff breaking on your bike while you'd much rather be riding. However, in my opinion (nope, not humble at all), to have a problem with stuff breaking when you (and I realize John that it wasn't you - I'm referring to the general, non-specific "you" ) fall down and go boom seems, well - out of touch with reality. No matter at what point in time after the crash the breaking happens. For all we know, the crash may have shifted parts of the exhaust system to the point where it's stressing the studs (thus having the shift be the cause rather than the crash itself directly) - similar to the tubers with a hastily installed exhaust. Not saying that's the case, but it would explain the delayed breaking. Just a thought. I think it would be prudent to actually research (and I don't mean just hear-say and individual case reporting) and find the cause of the stud breaking before pointing fingers. Henrik |
