| Author | Message | ||
     Vonsliek |
does anyone racing an xb12r (mine is '05) know of the use of solid-type (ie: non-rubber) front motor mount replacements for the stock rubber isolator? having many problems killing these things - even the revised ones .. paul. | ||
| Anonymous |
This is a very bad idea as the vibrations through the solid mount will tear the bike apart. It also will put impact loads into parts not designed for it. | ||
| Yohinan |
As anony mentioned, don't do it. Think about it in theory. What is a solid mount going to provide you over a rubber mount? All it is going to do is provide a harsher ride, more vibration, less vibrational absorption, add to the wear and tear of other "soft" parts, etc... I cant think for the life of me what in this particular instance a hard mounted part would provide over the stock/rubber piece. Edit: I just thought of something else. In your particular case with the symptoms your experiencing this part (if installed) is going to make it worse. Right now your front isolator is wearing out prematurely because it is my belief something on your bike is tweaked. Therefore this rubber isolator is the weakest link in the realm of parts on your bike. If you remove this and put a solid mount in your now installing a part that will most likely not be the weakest link anymore. Now your going to be breaking something else. This may be be one part or several. Only way you will know is if you do in fact swap this hard mounted part in. Hopefully this new weakest link, whatever that happens to be, is not something that will cause a catastrophic failure and lead to you crashing yet again, if not worse doing damage to your bike and more importantly yourself. It's not worth it. As a collective we can figure out what is causing the issue. Something on your bike is tweaked we just need to find out what it is. Can you give us a very specific list of parts that were replaced after each accident? Also exactly what type of crashes were each of them? Be very specific here. Left side, right side, high side, low side, head over head rollovers, side over side rollovers, etc... Was the work done by a shop or by yourself? Who did the damage assesment and purchase of parts each time? Were any parts left on the bike that may have looked questionable but it was determined they were "ok?" (Message edited by yohinan on January 03, 2007) | ||
| Slaughter |
Why? I've heard stories about the stock mounts being weak but in a few crashes, I've broken many things but NEVER the mount. I've also torn out the front mounts from the cylinder (still not breaking the mount) Again, like the above folks indicated, you'd be putting much more vibrations into structures that were never designed to do so. Maybe in a drag bike it'd be an advantage - where you are tearing the motor down every race weekend after a couple miles... but for road racing, I'd stay away from anything that eliminated ANY vibration isolation - at ANY place on the motor. | ||
| Vonsliek |
ok .. & thaks for the considered replies .. so, is there are replacement material that is *soft* yet perhaps a little more durable? like say teflon-type materials? .. & i am not an engineer nor materials researcher so i may be more off the mark than usual .. while i appreciate & respect the logic of what is being & said & that alone shd perhaps kill my thread, i am duty-bound, as an unconventional-type, to consider alternatives. ::crashes:: ::first crash:: lowside loss of front on snow gravel (during a chinook (warm spell in nov in calgary, alberta, canada)) while cornering. lowsided to left, hit median, reversed to lowside turnaround spin on rightside, trapping my foot & right leg under r footpeg. right front fork & front wheel bent. triple tree snapped in 2. lower triple impacted against yoke of frame, leaving a very small dent. magnesium front fairing on leftside cracked on lower attachment point at fixture mount. various minor scrapes on body work (r side), snapped r footpeg, bent & snapped r side clipon & brake lever. minor scratch at rear axle on swingarm. was considered an insurance right off .. i took part payment & kept bike. cost me CA$2000 in parts to fix damage. i did work w/ friend - we tapped in steering-head bearings ourselves, as we didn't have bearing press tool. bike was certified safe & salvage titled by dealership (calgary harley-davidson). they wrote a near total replacement of parts inventory for insurance but privately the service manager told me i cld fix the minor damage, as long as i didn't mind cosmetic blemishes & just wanted to ride it. i replaced entire right fork, but left was deemed good - i had another sportbike shop inspect forks, as i was keeping my options open. as well as new wheel, new brake disc was used. headers remain scratched. ::next crash:: nasty off while clutching a wheelie in 1st gear on public road at night at abt 40kmh .. bike took off, went vertical & gained some altitude before landing squarely on its ass .. then flipping a bit into the kerb & buckling front wheel again .. miraculously, only minor damage to bike - i nearly brooke nek, had bad concussion & smashed knee cap! replaced front wheel & lights that were damaged, as well as r clipon (again) & sundry small parts. ::last crash:: missed braking marker for chicane at racecity, saw concrete retaining wall in front of me, hit rear brake hard to scrub off speed & went off road .. no recollection of what happened to me & bike, other than brutally hard THUMP! on right side of back & then seeing hands in the air framed by blue sky & after a couple of seconds, decided i was no longer moving & hence got up * tried to remount, but corner marshall put a stop to that. just a lot of grass in bike. race team mechanic inspected bike & decided it was safe, so i rode it home. ::important point:: after each crash i replaced rubber isolator (last 2 were the updated variety) .. HOWEVER .. the last 2 mounts failed PRIOR to crashes 2 & 3 .. i delayed replacing them. i rode to laguna seca on a failed front isolator & back (quite a trip from calgary to cali) & did all the track days .. IMPORTANT POINT 2 .. the harley dealership inspected isolator & because they couldn't get one in for over a week, the service manager told me bike was *safe* but wld just chatter a bit under breaking .. so - desperate track-addict i am - i took bike & hoit the road w/ no replacement isolator ... so, now i have fessed up .. i guess the litany shall desend upon me?! ;P ok guys, lemme have it .. i deserve it a bit .. but can we keep it in the *useful* realm & spare me the *idiot* stuff .. no point stating the obvious! ;P paul. | ||
| Yohinan |
Just to clarify we are not saying the stock mount is weak. As mentioned is it the same piece used on the XBRR (which takes much more abuse than the average Buell). I am going off the guess that your not in fact breaking the mount itself but wearing out the rubber within the isolator. Ok after reading your last post here is my opinion. left fork issue - if the right fork took enough damage to bend it there is a good chance the left took some type of hit. How did the "shop" that looked at it determine the part was in fact good and did not need to be replaced? What type of machines, measuring, etc was used to state replacement was not needed? When you have the front wheel off the ground and pointed straight ahead if you spin the wheel does it rotate freely and/or exhibit any type of abnormal rotation? steering head bearing - sounds like it may or may not have been installed correctly. I recommend following the FSM and checking it not only with the front wheel off the ground and pulling/pushing but also using the spring scale to determine correct resistance is acquired. If determined to be out of spec install both upper and lower bearings with a correct type of bearing installer (lube the outer portion of them with oil prior to installing to ease in installation). Frame - definitely follow both Diablobrian's and mine recommendations to have GMD Computrack inspect your frame for possible damage. They will be able to see if other parts are out of whack/alignment also when doing this. If you want the easiest way out of this here is what I would do. Check the steering head bearings as recommended by the FSM. If they are deemed good then go with GMD as they will be able to tell you if your left fork, frame, or whatever else on your bike is causing issues. I would have a GMD chassis optimization check done regardless as I am 99 percent sure you will notice an improvement in both feel and drivability. Your bike has obviously taken some serious damage in the past. This shows two things, just how resilent our bikes really are at being able to take this kind of beating and also how fragile they really can be. When you find out exactly what part/s need replacement or fixing please let us know. It would be great to see what is causing your issue. | ||
| Vonsliek |
u know i really like the kid of intelligent, considered feedback i have been receiving here .. & timely too!  i convinced my housemate to keep his xb12s after he was going to sell it to get a ktm superduke .. he decided against the duke .. i cannot think why?! ;P anyway .. GMD is out of question at this juncture .. due to lack of proximity. i always chk front end on stands (ie: rear stand & nothing under front except under muffler) .. the only missing thing is the spring scale ... front wheel rolls true to the eye. they chked forks by *i have no clue* wasn't cynical enough at the time! :\ when spring comes up, i'll ride down to usa & get GMD to chk bike then .. if i am forking out the better part of CA$20k for this dreambike, then i may as well get serious ..  ouch! | ||
| Slaughter |
Paul, Some "poor man's racer" suggestions... 1 - If the forks are leaking oil, they're bent. If not, you can run them IF they don't bind. 2 - IF you haven't ripped the front end off of the chassis, you can still race it. BAD wreck will usually tear the triple clamps and NOT wreck the chassis. You might save your $$$ on computrak if it means losing too much time. They WILL tell you if it's straight, if components are in line - but IF it's bent, they can't always tell you how to straighten it (not a good idea unless you can do proper inspection anyways) - it is money well spent but unless you really are afraid that you've bent it badly, you might put your money elsewhere at first - especially since there's no GMD near you. I've broken Suzuki SV frames in a couple different ways but in a half dozen crashes at speeds up to ~~125MPH have never bent an XB frame to where it couldn't be raced again. Pic is Jeff Ecklund's XB after a tumbling get-off at about 135MPH in T8 at Willow. Front end broke off as it was designed (at the triple clamps) It was race ready the next month - most expensive parts were new bodywork. We couldn't see that one fork leg was bent until we took the forks apart. One leg was slightly bent and it was replaced.  | ||
| Diablobrian |
I was thinking about it, have you taken a look at the rear isolator? It seems like the front is absorbing a lot of excess motion if it is going out this quickly. I agree with Slaughter about the durability of the Buell chassis, the reason I made that suggestion is because there is apparently something (invisible to the naked eye) wrong with the bike if it eats 3 front mounts in a year. If you have it torn down I'd suggest a very careful inspection of all of the motor mounts and rubber inserts. As far as a material for inserts goes Buell has done very well, maybe a polygraphite material like PST uses to make high performance bushings for the old muscle cars? The material in there needs to be resilient. It is supposed to dampen, not transfer vibration. | ||
| Court |
Paul: Something is not right. Drop me an note with your contact info. Court | ||
| Buellshyter |
Vonsliek, you might want to give up traveling by two wheels and stick with your two feet  | ||
| Vonsliek |
buellshyter .. SCREW YOU!!! hahaha! |
