| Author | Message | ||
     Buelltours |
Hi Guys! Just had a bolt snap on the front motor mount (2000 S3). My dealer only had 1 bolt in stock so I started looking for an alternate source. If I recall correctly, someone here on the board bought a whole bunch of them at one time. Does anyone have a good source? There Foremost F911 bolts are kind of rare - I could not find a bolt supplier who carries them. Is there any good alternative? I would like to buy 10-20 of them for future issues... Also, didn't someone here on the board buy one of the Stenzel braces from Germany? I read in the German forum that there were no known bolt failures. Anyone here have an opinion? Anyways, thanks for everyone's help! | ||
| Ebutch |
Cornel got mine from dealer, special order from Buell,2 years ago at 102,200 miles,snapped both.Also American Sport Bike. | ||
| Ebutch |
Also blue Locktite torqu to spec.22,700 miles since.  (Message edited by ebutch on May 27, 2009) | ||
| Oldog |
fsm calls for red loctite, and torque to 60ftlbs on oiled washers, loosen and retorque note this is for an x1 E-butch is right check American Sport Bike Al has em most likely | ||
| Ebutch |
YES,RED,could not remember off top of my head Jim.As I remember you put out a nice spec sheet on those Bolts. | ||
| Buellistic |
BUELLers: You'll have to "UNDERSTAND" that the FSM can and will be "WRONG" on certain important issues and if "YOU" can not tell, you are just "SOL" !!! REMEMBER THIS: Factory Service Manuals are written for "technicians" and proof read by "technicians" !!! MAY THE LONG LASTING BUELL BE WITH YOU !!! | ||
| Ebutch |
Ya.But a good place to start!I am only a shade tree mech. since 1959 about 750,000 motor cycle miles.10 bikes,4 with 100,000 miles or more and can do better in some things than a prof mech.Which Buell Dlr. has messed up my bike on oca.Yes there are better shops but I make do! Have a nice day Lafayete | ||
| Court |
>>> proof read by "technicians" !!! While that makes a catchy slogan it is inaccurate information. | ||
| Oldog |
Buellistic, If you think the Buell manuals are lacking, try a Hayes automobile manual or a KTM manual they both are horrible. The FSM is pretty well written, I would advise any one who wrenches on their bike to get one, read it and re-read it, Oh yeah Butch, you me and a few others perhaps a "@#$%@% broken head bolt club" ,section of badweb?  Several folks have suggested differing grades of fasteners, and possible causes for the failures. the most recent was in conversation with none other than Wes Brown [ Pammy's Hubby ] he suggests that the rear isos are a large part of the picture. the issues reguardless are not as bad as correcting the mess after the breakage I had posted up about mine about a month or 2 ago, the heads came back Tue from Cycle Rama I get "all excited" just looking at them, If you need to have the bosses checked and repaired, well worth the wait  | ||
| Eshardball |
Check the post where one of our members had sleeved his front mount and cut recesses into the heads for the sleeves. This looks like a great improvement. | ||
| Oldog |
I hope that the mod works, I dont want to be negative but I think that it wont make much difference, I could be totaly full of organic fertalizer here, BUT 1. the mount is retained by CLAMPING PRESSURE exerted by the bolts between the head of the bolt and the cylinder head. 2.the pressure is sufficent under NORMAL conditions to absorb the vibes and not allow a SHEAR load to be applied to the bolts, 3. One mode of failure is when the clamp load is released and the bolt is placed in shear The most common one is left side ( as seated on the bike ) the failure may be caused by overloads from stunting, overloading, faulty parts, or misalignment. 4. the failures have some common hallmarks, the metal on the mounting faces will show signs of deformation and mechanical damage due to impacts and/or rubbing against one another. 5. the failed bolts that I have seen appear to break in a similar manner this has been examined by several engineers who are members of this board and knoledgable on this subject, the failure is loss of CLAMPING, I Believe that a billet mount will eliminate part of the issue, but mechanical overloads or degradation of parts are also causes and are difficult to predict. the Mount uses 3 point rubber mounting allowing the engine to move in one plane [ UNI PLANER ] The tie bars restrain the engine and allow movement in that plain, the rear of the drive line mounts at 2 places at the swing arm pivot, the front hanging from the head by basicaly 3 bolts 2 in the head that clamp the mount to the head, one to assemble the headmount to the front isolator, the bolts used are marked 911 and are special high strenght bolts suitable for this purpose. I suspect that any modifications that dont enhance the clamping at the head on the front mount dont help, My 0.02$ busted bikes suck.. | ||
| Fullauto |
I've now snapped two left hand engine mounting bolts with a NRHS billet mount. From what I've read I appear to be the first to do so. It is getting rather tedious to fix so I thought I'd attempt to fix the problem once and for all. Both times the boss on the right hand side has been torn out. If there is no shear force, then why does the bolt always break flush with the head? The problem with thinking of these sorts of joins as a rigid entity is that it is not! After many years of playing with firearms especially one finally learns to understand that even structures which appear rigid are more fluid when the action is happening. By getting the dowels to take the weight and the bolts to take the load in tension, hopefully the problem will be solved. As the man who jumped from the 20 story building said when he reached the 16th floor.......... "So far, so good" | ||
| Fullauto |
You've also got to take into account that the whole front of your motor is held UP by these two bolts. IF the two bolts held the weight VERTICALLY, would they still break? I might be full of nitrogen emulsion as well, but I want to fix the problem. | ||
| Preybird1 |
Don't feel to bad we just put a xb iso on that is $82.00 and it is already ripping away the rubber from the mount. | ||
| Oldog |
FA what condition are the rear mounts in? | ||
| Oldog |
Interesting reading http://en.wikipedia.org/wiki/Bolted_joint#Locking_ mechanisms particulary the failure modes. I am trying to get information on "911" bolts I have never seen any thing on grade 9 bolts | ||
| Oldog |
Don't feel to bad we just put a xb iso on that is $82.00 and it is already ripping away the rubber from the mount. some thing else is wrong......} | ||
| Fullauto |
Rear isos were replaced about two years ago with the uprated ones. I had the swingarm off last year and they still looked fine. I'm pulling the swingarm off soon for another service. I'll check them again then. | ||
| Ebutch |
My 2 cents.2 Buells ,188,000 miles.One rear iso right side of S2T went about40,000 miles.Still use old style iso.When it went felt like broken frame right side! Could see rip!+ can tell what side without looking by weaving in road intenceafied on side ripped on weave! | ||
| Dave_02_1200 |
I think the Stenzel brace might be the solution. It puts the top mount in double-shear eliminating the rocking forces that are present with the original single-shear configuration. I now have one on my 2001 S3T. Time will tell. | ||
| Oldog |
More Reading: http://www.f911.com/fore2b.html The special bolts grade 9 these are the bolts that Buell uses on the motor mount. stay tuned .. Full, I had the old ones off and they looked ok when I replaced them I have no idea other than if its ripped, its bad the 911 bolt link is interesting in that the bolt can withstand more tension than a grade 8 bolt, the chrome and nickel content is higher providing better toughness and strength (Message edited by Oldog on June 09, 2009) | ||
| Buellistic |
BUELLers: Why has no one suggested replacing the bolts with "STUDS" ??? MAY THE LONG LASTING BUELL BE WITH YOU !!! | ||
| Oldog |
Why has no one suggested replacing the bolts with "STUDS" ??? What woud the advantage be? its interesting to consider. } | ||
| Buellistic |
Oldog: To start with, less machine work on the part ... "i" was always told "STUDS" are stronger!!! If "i" ever have trouble with my front motor mount it will get studs ... | ||
| Cyclonemick |
What do you mean by studs?? I'm assuming your not refering to 2x4's  | ||
| Bluzm2 |
I've seen a number of broken front mounts, tha last was at Homecoming last year from an S3. I've also observed another thing after inspecting a number of removed front mounts. The broken mounts all no longer had a flat faying surfaces. They all had curves at the top and bottom. Imagine a motor mount with loose bolts, rock it back and forth (front to back), the tops and bottoms would eventually round over as would the head. Something else I observed, the left leg was always worse than the right. The two old style mounts (like the S2's) with the "bar" across the two legs either had no wear or very little. I've mentioned this before, I wonder if there is some weird harmonic thing going on with the legs. I've only disassembled one motor with a NRHS type mount, it didn't have any wear. I wonder if it's an issue with initial wear on the head and mount due to incorrect torque or assembly. The wear starts until the left fails. Replacing the bolts only fixes it for a while since the surfaces aren't flat. They break again do the the same "forces" that broke them the first time. A NRHS type mount on a "worn" head could cause the same issue I suppose. All this is purely theory, simply garage observations. I do know that when I redo my bikes, I will ensure that all faying surfaces are flat and use a NRHS type mount. Brad | ||
| Oldog |
Brad the markings on the mount were consistant with what you describe on the right side, the left was quite different, but the root cause appears to be the same, mount gets loose for any reason bolt goes into shear and pow, time to go fishing..... Al has voiced the same concern on harmonics related to the mounting arms and the older stiffer versions of the mount holding up better. | ||
| Fast1075 |
The idea for the studs seems like a good thought..I'm willing to bet that A.R.P. has some studs that are far stronger than the OEM bolts. As far as using studs go, the two primary reasons to use them are (A) parts that get disassembled frequently will wear out the threads especially in aluminum...(B) Ease of assembly...it is often far easier to slide a part onto a stud than to line up the hole and feed a bolt into it...or for ease of disassembly...one good example is exhaust studs...if the nut rusts on...it can be removed by various methods, allowing better access to the stud for removal or repair of the threads on the stud...(a skilled torch operator can cut the nut off without damaging the threads on the stud). Another possible tack would be to use a Belleville washer to help maintain clamping torque...in any case, I am in full agreement with the fact that the surfaces being clamped together must be completely parallel in both axis.. Al's concern with harmonics is a well thought out idea...harmonics can cause considerable distortion and component failure while leaving little evidence. If the parts show brinneling...they HAVE been moving around....and if a tuber isolator is like a blast isolator in construction, it is easy to see why they fail...and it is easy to see why the "big twin" isolators are not prone to failure..a side by side comparison proves the load distribution is completely different between the two. One is in constant vertical shear while the other is in constant compression. | ||
| Fullauto |
When I fixed my head this time around I looked at alternative bolts and found socket headed cap screws were available which were grade 12. The only reason I didn't use them was that the ones available in the local bolt shop had shank lengths either a bit too long or a bit short. To buy the correct one would have meant buying a whole box in so I stuck with new Buell bolts. I'm off to the big smoke in a couple of days so I shall hunt down the correct ones. However, I may not fit them straight up as I want to know whether my dowel solution works. Might save them for next time (!!!). As the bolt breakage leads to all the other carnage, maybe higher grade bolts are the answer. | ||
| Fullauto |
God, I love this forum ! |
