| Author | Message | ||
     Buellgrrrl |
Well, after 35,000 miles a big time Buell jynx has finally hit me- while doing a 35k service I found the front isolator mount broken on the right side of the upside down "V". Cause appears to be a left side bolt holding it to the head that vibrated loose, but not loose enough to be finger tightenable. Threads into the head appear to be buggered also. Looks like a new front isolator mount. bolts, and a helicoil if not a new head will be needed. Should be amusing to hear the excuses they give to not cover this under extended warranty- anybody know of any Buell knowledgeable dealer's shops near Minneapolis? BuellGrrrl | ||
| Marks3tbillet |
You did good. I lost the front isolator at 12K miles on my 2000 S3T. I ride very easy too. Sorry I don't know of any shops in your area. Mark | ||
| Loki |
grrrl, Try St.Paul HD/Buell out on I94 and Century Ave. Used to treat me good. Then again if you are a westsider...... | ||
| Blake |
If you could post a pic of that, I'd be much obliged. Good to document this kind of thing via photo. It makes it much more real and more significant. That kind of failure really should not happen. I'd like to take a look at the possible root cause. If you can get some good close-ups of the failure regions on bracket, bolt and cylinder head, we may be able to do some forensic analysis that may shed some light on the issue. | ||
| Buellgrrrl |
Well, St. Paul HD-Buell started work on it in just a couple days, to their credit. The insurance company HD sold the extended warranty for will pay for the front isolator mount, but not for the labor to check the rocker boxes for damage from hitting the frame. Looks like they're trying to weasel out of there warranty obligations... And as tempting as the Uly looks this will probably be the last HD product I buy. Time to put all my old BMW airheads back on the road... | ||
| Tramp |
Don't give up so easy. you say you were doing the 35 service yourself when you found it? has anyone else other than HD service ever touched that thing before you? It sounds as if someone once removed one of the iso/head bolts, before. sound slike more of a bad tech thing prior to your ownership.... | ||
| Buellgrrrl |
Thanks Tramp, and I've owned the bike since new and up 'til now have been the only one to wrench on it. | ||
| Tramp |
That absolutely sux. I am feeling your pain, for sure. I look forward to those pics- like I say, don't give up. some of these buells will go forever, and the new ones are likely more smoothed-out, by now. I hear ya about the old airheads, though. hard to go wrong with them. Don't roll over on buells just yet, though- i've had many an airhead fanatic come limping in with thrashed input shaft splines because noone had lubed them when the clutch was done, and i've had many shafts with equally shredded splines come through my shop doors emitting a cacophonous, and very expensive howl equalled only by that of their owners when i explained the cost of shaft replacement. all bikes have problems. all of them. buells and bmws have fewer than most. | ||
| Bluzm2 |
Buellgrrrl Drop me a email. I'm in the area and can maybe help you out. Too nice of a day to spend typing. Sounds like they need to replace the head anyway. The rocker boxes are already off... should be no big deal. I have a set of middle and upper covers if you need them. Brad | ||
| Tramp |
the real sticky wicket here is the fact that buellgrrl has, for the past 35,000 miles "been the only one to wrench on it". all bets are really off, as far as Warranty is concerned. Try to get whatever you can, but when push comes to shove, take the new isolator and run. let me know if I can help, I have a lot of spares lying around. | ||
| Panic |
I'm not sure I understand the dynamics of the motor mounts. From casual inspection, it appears to me that the isos "suspend" the engine/transmission/swing-arm mount in the chassis without stress - except for the front shock mount. Since all the locating heim links are transverse (laterally across the chassis), there is no restraint of engine movement from shock/spring resistance on swing-arm travel. The forward head steady looks like the mount taking the largest bending force when the engine reacts to shock movement (the others have the surfaces slide past each other in shear). Am I missing something? No, this doesn't appear to be in KV. | ||
| Djkaplan |
I don't think you're missing anything, the engine in the tube frame bikes is used as a stressed member because of the unconventional shock arrangement. The key to front mount life may be constant monitoring of the two mounting bolts in the cylinderhead (a theory proposed earlier by someone more astute than I). I've used my bike pretty hard and never had a problem with the stock front mount (except that it's really ugly on an M2 without the breadbox). When I removed it a couple of months ago, the bolts were still holding their torque. | ||
| Rick_a |
I broke a cylinder head at 19,000. Consider yourself lucky! | ||
| Panic |
Doesn't it seem that the fore-aft movement of the engine under shock loading is being taken by something that isn't up to it? The bending force is trying to lever the bolts out of the head and break the mount. It must also be at or near the compression limit of the iso at the steering head, which may be why they look so beat-up. Another link with poly bushings aligned fore-aft to connect the existing top (center) mount with the frame will at least set a limit without increasing vibration, since it won't be tensioned with the engine is "relaxed" position. Under shock loading the engine will move and compress the isos as normal, but will bump against the poly before the isos reach full compression and transfer stress to the front mount and bolts. | ||
| Newfie_buell |
I'd say they break due to the head bolt loosening causing more vibration than normal!!!! If thats the only problem you have had then your lucky. Lots of little things go wrong with these mystical beasts that are a hell of a lot easier to repair than most other bikes. Keep the Faith. | ||
| Natexlh1000 |
Mine just started to vibrate slightly more than usual but my front mount looks ok. The usual culprits are also ok (exhaust, primary chain, rear isolators) Does the front mount look different when it fails? I mean, would a failure be obvious? | ||
| Tramp |
look at the front isolator, Nate, not the iso mount. [ CAUTION: E-HYPOCHONDRIASIS ALERT]  (Message edited by tramp on September 06, 2005) | ||
| Bomber |
Nate -- my front Isolator (mount was fine) showed a crack around the periphery of the rubber portion -- more easily felt than seen, tucked up in the dark like it is -- if you've got access to another tuber, check both -- a basd front iso will be obvious to the eye (and fingertip) with this failure mode | ||
| Nitsebes |
 tore iso | ||
| Natexlh1000 |
CONFIRMED. Looks fine from above but underneath it is torn. Looks like 3/4" bolt, that's it? Is it as simple as it looks or is there a trick I should know? Would it be more easy if I took off the tank? | ||
| Tramp |
you really should remove the tank, nate. got to trust the trampster  | ||
| Koz5150 |
Whatever you do don't loosen the bolts attaching the brace to the head! I swapped mine in minimal time. The part is the same as a Dynaglide mount so there are aftermarket parts available including polyurethane products. | ||
| Rick_a |
Actually it's the same front iso FLH's use. Dyna's have a totally different set up. | ||
| Tramp |
...which brings us back to the header-post of this thread. sounds like someone removed on buellgrrrl's isomount-head bolt (prior to purchase?), which lead to the "buggered threads" there. if only the w-work had been done (for better or worse, trust me, i'd much prefer buellgrrrl to wrench on abike than most HD techs) by factory-authorized service facilities, she'd have a clean case for warranty replacement. when the factory shop hasn't done the service interval w-time, the warranty is rarely honoured. | ||
| Panic |
Has anyone tried to sub an AM poly for the front/upper iso? Since it compresses less it will also limit the travel of the engine when loaded by shock action. | ||
| Tramp |
I've thought about similar things, panic. like using polyurethane bushings from performance car kits or skateboard wheels. | ||
| Bomber |
it's an ez job, only tough part is getting the torque wrench on the fasters -- crow's foot wrench helps greatly . . . . .. havn't heard of alternate materials being used for the front ISO -- I know htat American Sport Bike used to sell aluminum replacements for the two rear isos once upon a time, warning of increased vibes if installed | ||
| Mikej |
Last I checked he still has those rear units on the web site. What's the torque adjustment when using a crow's foot. And did you re-use the bolts, nuts, and washers? I need to do both of mine, procrastinating until it snows or until I get around to it or until next summer or until I trade one/both off and throw in the new units with the bike(s). | ||
| Natexlh1000 |
I can't get a tool on one of the bolts. I can't see any way of doing it. right side 9/16" bolt | ||
| Panic |
I've successfully used wire cable as a restraint against fairly heavy loads in automotive apps (engine torque strap). Remarkably small multi-strand commercial cable can be looped around any large fasteners aligned fore-aft and tightened using the common U-bolt and lead anchor so that there is some slack. Only takes load in tension, so for complete control of shock movement you need a pair. Don't use a turnbuckle unless it's aircraft quality. Result: no vibration transmitted (doesn't change the "float" of the isos), no noise, no rust, no adjustment, weighs nothing, costs nothing. |
