| Author | Message | ||
     Sloppy |
I had a chance to disassemble the factory front isolator (Mfg: Barry) to determine how / why these go bad so quickly. I noted that there was only a 3/8" strip of bond between the metal sleeve and the rubber (so only about 20% of bonding). There was no rubber adherence for 80% of the surface area - so there is very little surface area holding the isolator together. It's no wonder that these fail so quickly. This is likely a manufacturing defect as the bond appears to be a glue that is wiped on the sleeve prior to insertion into the rubber isolator. I would expect that the glue should be applied evenly, but in this case it was only brushed on one side. And depending upon who (if made in China) or what (if made in USA) put the glue on the sleeve would determine how long the isolator would last. In future I would only recommend the -79D replacement reamed to 1/2". The -79D doesn't rely upon a bonding of the sleeve to the rubber - instead the sleeve rests on top of the rubber. Note - you will need to use a different washer assembly rather than just use the factory "D" washer. I'm curious if anyone else has a failed isolator if they can press out the sleeve and see what kind of bonding surface they see. This could indicate why some isolators last a long time (if they have more coverage) and some less. | ||
| Dpg |
My NRHS mount arrived today so I'll be reassembling the front mount assembly this week. That billet mount is really nice item. Plenty beefy compared to the stock bracket. I bought a complete bolt set and a new isolator although I found that the original isolator was undamaged. One thing I noticed immediately was the difference in the rubber hardness/density between the two isolators. American Sport Bike has a note regarding the replacement isolator on their website that this would be a Buell replacement, but that the rubber was softer and would probably not hold up as long as the old stock items. I guess I'm lucky to have the original as I imagine the new softer unit would indeed wear out faster in comparison to the stock unit. Same BARRY mfg. ID and the part number is molded into the rubber grommet this time too. Oh, so is it RED Loctite or BLUE Loctite as the preferred thread lock on those 911 bolts. Red would be my choice IF I didn't anticipate having to do this repair again since that would probably maintain the torque better than blue. I also checked the Belville spring washer site, but noticed right away that these washers were appropriate IF a loss of setting or torque can be tolerated. In this case, by definition they aren't the solution. Safe ride, Gary in Oaktown | ||
| Sloppy |
To clarify - the root cause of failure is NOT due to the rubber. The failure is due to the metal sleeve not bonding to the rubber. So it doesn't matter if the rubber is harder or softer. What matters is how the sleeve is adhered to the rubber. | ||
| Dpg |
I'm confused as to how the method of adhesion between the metal tube and the rubber grommet is the cause of the bolt failure issue. Since the vertical bolt connecting the isolator to the motor mount is supported by the D washer and the standard washer and crimp nut the weight of the engine assembly rides on the top portion of the rubber grommet. I'm no engineer, but the metal tube/sleeve would seem to me to be to stabilize the line of travel and deflection the bolt makes when the rubber grommet is compressed from vibration or road roughness. If the rubber degrades or is damaged (especially the top portion) that is when I can see the bolt basically bottoming out and the vibration/force transferring directly to the 911 bolts. Safe ride, Gary in Oaktown | ||
| Sloppy |
Topic here is the top (steering head) isolator failure, not the 911 bolt failure... sorry for confusion. (Message edited by sloppy on June 30, 2009) | ||
| Fast1075 |
I had three isolator failures on my Blast in 5500 miles...(same set-up basically) and arrived at the same conclusion as Sloppy....Now I have the -79D iso and expect no further failures. | ||
| Dpg |
Oh great... I have a salvaged 2000 Blast I put together for my wife! I understand when the bolts on a Blast break off the engine drops to the ground.... Maybe I should get her a skooter LOL! Safe ride, Gary, DPG | ||
| Oldog |
I have 2 that have failed I am using the drag specialties iso, that you dont have to drill. Jramsey is running a drilled updated 79d we are compairing notes on this as time passes. sloppy one of the parts i have that has failed ripped in a manner that suggests that the bond had not failed but the rubber is too soft, any pix of the autopsy? also the barry and other isos, have a large rubber area on top of the plate that is in compression under the dee washer. I think that you are likely right that the glue may be breaking but I also think that the rubber is a bit too soft. what did you do to evaluate yours? | ||
| Oldog |
DPG the loctite is the red #272 the basic idea, is that the bolt holes are clean ( read steareal ) red loctite the threads of the 9-11 bolts, oil the washers lightly and torque to 60 ft, release and retorque | ||
| Dpg |
60lbs, release and then back to 60lbs??? Oops, I read the FM torque chart and the front mount is spec'd at 100-110 ft. lbs. so that's what I did. Threads didn't strip out so all's good for now. Safe ride, Gary in Oaktown | ||
| Oldog |
Dpg, the bolt that goes down to 110ft is the HANGER, the head mount bracket bolts, are installed as described prior, if you pulled them to 110ft they are Grossly over tightened, this may be hazardous to your health. the hanger use blue loctite, and goto 110ft the iso mount is about 30ft IIRC 110 ft on the head mount bolts  | ||
| Sportyeric |
I got 60,000 miles out of my original front isolator. I got 2,000 out of the replacement. I didn't think to keep the failed one for an autopsy or a free replacement, unfortunately. I have now installed a Drag Specialties one because that was what was on hand. It seems to me that I have a whole lot more vibration gong on. Vibrates like my Sportster. Is that to be expected or should I look for more gone wrong. (Rears were also new and seem undamaged.) | ||
| Gowindward |
Hey Eric, Yes the DS part is harder rubber and does cause more vibes. I guess a lot better than a failed part every few thousand miles. I went three OEM parts in less than 1 year. | ||
| Mmmi_grad |
60 k out of the original? thats cool but the way I beat on mine and do wheelies ill be happy with half that. They had to redesign the oil gear, why dont they bring back the original spec ISO!!  | ||
| Sportyeric |
Has anyone tried to get Harley to warranty replace a failed one? I was willing to accept the possibility of poor installation on my part for the failure, but for threads like these. Not to mention that its not exactly rocket science to install them. | ||
| Dpg |
The single long bolt that goes through the isolator and down into the NRHS mount gets torqued to 110lbs ? I couldn't get any of my three torque wrench heads to fit at the top nut due to the plate which is part of the frame. No way to get a torque wrench into the space available on the motor mount either. Since the nut is a crimped locking nut why such a high torque factor? While 110lbs on those two mount-to-head bolts is a lot, 60lbs hardly seems enough to control what many have said is a cause of bolt failure i.e., the mount moving and eventually causing a shear factor which causes bolt failure. Where in the manual does it show a torque factor for the mount bolts. All I've ever seen is mention that we shouldn't remove the mount and that 'repeated' removal and re-installation could cause problems with the internal threads on the head. I torqued those bolts to 60-90-110lbs. Safe ride, Gary, DPG | ||
| Mmmi_grad |
i just checked my head bolts today after a new front mount set up with original stock iso in great cond. }3 weeks ago. No problem found again. Bolts are solid and were not loose at 60lbs. I agree that the single bolt through the ISO 110lb spec is funny to me too. A person with skill can crank it down to about that and be rightous. (Message edited by mmmi_grad on July 04, 2009) | ||
| Dpg |
Bowing to the wisdom of the board, I changed out the head/mount bolts that were over torqued and installed the other new 'back-up' pair I had purchased. Did the red Loctite again and the torque to 60/loosen/re-torque to 60 process. Hope this will hold up for a while. I guess if you use one of the open end wrench / socket adapters you could use a torque wrench in those tight quarters for the vertical bolt and nut. Now I have to wonder if that 110lb torque spec for this bolt is intended to compress the isolator to a certain extent. Time will tell I guess. Safe ride, Gary in Oaktown | ||
| Gowindward |
The 110 ft-lbs is not about keeping the bolt tight and from coming loose, but about preloading the bolt beyond it's normal load, to prevent fatigue failure. | ||
| Dpg |
Aren't we compressing the rubber grommet on the isolator when we torque that bolt to 110 lbs? I'm guessing the rubber is cushioning both vertical and lateral movement. If that is so, and the bolt isn't bottoming out on the metal sleeve going through the grommet (which would nullify the vertical cushioning) I'm not getting the high torque value. In addition, the density of the rubber on different model isolators would also become a non-factor. Has the factory provided any direct input to the owners on what the design intention was and the problems we are now dealing with? Safe ride, Gary in Oaktown | ||
| Psycrow |
DP, no you are not compressing the Iso Rubber. It has a metal sleeve the bolt runs through, so the "D" washer on top and v mount below are sandwiching the the metal sleeve. The "D" washer sits on top of the rubber but its metal on metal with the sleeve. Psy | ||
| Sloppy |
I'm not sure why we have two topics on this post - this post is for isolator failures of the OEM model... Anywho, on my replaced OEM isolator the rubber did indeed tear, BUT the tear took place due to concentrated stresses in the ONLY location that the rubber and the sleeve made contact. And this bond was extremely small, and hence for my isolator, the cause of the failure. My autopsy consisted of cutting a groove far outside the torn rubber and using a press to slowly push out the sleeve. As the sleeve pushed through I continued to cut the rubber loose until I could see that there was hardly any bond between the sleeve and the rubber. The key here is that the sleeve had little to support it to the rubber isolator. I don't see any warranty issue here or any "what can the factory do for me". The bike model is past its business prime and while the replacement parts don't last long, it still does work. Like many other groups, it's up to us (and private industry - hello Al from American Sport Bike?) to figure out a longer term replacement. And I think the -79D is a reasonable replacement that requires a very small investment to modify for our bikes. If someone were to work with an OEM vendor to design these for 1/2" holes would be fortunate. BTW, I have noted that the -79D doesn't contribute ANY more vibration than the OEM replacement. (Message edited by sloppy on July 06, 2009) | ||
| Psycrow |
I might as well add this here instead of starting a new Thread. I too replaced a failed OEM front ISO with the Barry OEM ISO from Buell (soft rubber version) It was heaven on vibes for about 200 Miles and then total failure. The rubber tore completely away from the Metal Sleeve just as Sloppy described. I was pissed. Last night I installed the ISO from Drag. and took a 30 min ride to test. Holy vibes Batmam! It is shaking apart from 2 to 3k Rpm above 3k its just hand numbing. Others have said to give it 500 miles or so to settle in and I will but my next purchase is going to be the 79D ISO and a drill press. Just my 2cents added Psy (Message edited by Psycrow on July 06, 2009) | ||
| Mmmi_grad |
" I don't see any warranty issue here or any "what can the factory do for me". The bike model is past its business prime and while the replacement parts don't last long, it still does work. " I personally would have replaced the old shock myself if they could have eaten the oil gear or the ISO problem. That statement is Buellarious sloppy. | ||
| Sloppy |
Never had an oil gear problem and the shock was a voluntary safety recall - Buell was under no NHTSA rules, they did that themselves. The "iso" problem is that they don't last long but they are designed to be a regularly replaced item. Of course, regularly replaced isn't as long as we'd like...  Let's remember that the Tubers are an 11+ year old design from a brand new manufacturer. I'm not going to worry about it especially when there's so many other solutions available. Am I happy about it? No. Do I expect to be self sufficient and figure out a solution myself - absolutely! Waiting for someone else to solve my problems is called Socialism... | ||
| Mmmi_grad |
hilarious again. Ahhhh shucks sloppy your right. Ill get off my lazy ass right now and go fix the problem right now in my 10000 dollar garage for all of us. While Im at it, ill learn to never ask for excellence again from anyone while demanding it from myself because I am the supreme winner of the year!  is anyone from real linda around here? | ||
| Sportyeric |
I think that when the stock Harley/Buell replacement fails without lasting one riding season, it is faulty. Most last for years. If it happened to me again, I'd be asking for a free replacement. (But I'm got the Drag Specialties one installed now, so hopefully that's the end of it for a while.) | ||
| Oldog |
DPG: Please check through the archive on the old school section, there are several threads related to the iso failures, the hanger bolt, clamps with the motor mount and D washer with 2 hard washers to put a clamp load on the mount's molded in tube. My iso also ripped as decribed I BELIEVE that the rubber is too soft, and the barry part is off spec, or wrong spec. the DS part on my repaired X1 seems to be much like the original I plan on a close inspection soon to check the condition of the mount, and hardware. } | ||
| Oldog |
Grad; I agree with you that we shoud not have to fix this issue, I believe that Buell may a. not be aware of the problem b. may not have control of the supply chain (its HD's turf ?) c. have lost it in the overwhelming work load, that precludes support for our vehicles small staff many tasks to do. d. can no longer justify spending more than minimal time on these kind of things. who knows, they have addressed the oil pump issue, (brass gear) they never adderssed the shock issues beyond shaft breakage ( short life span ) the FI issues have been improved on subsequent year models Its sad that this cant be resolved by Buell but the answer seems to be Get the DS part, watch the sacred bolts, and live with it. [ btw I believe that the rear mounts have some thing to do with this as well.] My DS Iso & billet mount have 500 miles on them now, so far so good. | ||
| Gowindward |
A billet motor will be my next purchase.    |
