| Author | Message | ||
     Jimidan |
All but the last one of my front isolator failures can be attributed to riding two up for some distances...like the time we went on the Northeast Tour to Maine and back. We also broke one in Colorado...twice on different trips. This Buell S2 is the only bike I have that isn't a mono, so the wife has to be able to go on it. Usually, we are well loaded with luggage (but how much can you really put in those little hardbags and a tank bag/), but still below the gross max. We do ride a bit briskly (using all of the tire) and keeping up with single guys of their bikes. The S2 really isn't a very good sport touring bike for two up though, I have come to realize. I am thinking to buy a Honda Blackbird with hard luggage for the two of us to ride, or maybe a BMW. These bikes have a higher gross max and no isolators to fool with...and they are smooth, powerful and very reliable. Hey, I have given it my best shot...but I have to have some reliability to take trips with the wife. I will give my service manager a call and see if he is going to be able to warranty the "bad batch" (his words) isolator...if not I will drop Court a line. Thanks Henrik! Jimidan | ||
| Jimidan |
Hugh and Jose': The way my isolator usually tears is in a horizontal line about half way up on the TOP half. It looks like the weight of the engine contributes greatly as it moves in the vertical plane, as it always is in the front center initially. That was until this new re-engineered one I got that broke up all over. When I bought it the parts guy told me that they had been re-engineered...I liked the old ones better. I am not sure that adding the extra heim joint link will help, but it couldn't hurt. I doubt that Buell engineers are really sweating this problem as they probably are hoping that I will buy a new XB model. Not yet. jimidan | ||
| Henrik |
Jim; only happy to be of help. Hope you get it sorted out. As an S2 owner I'd sure be interested in any issues/solutions you come up with. Henrik | ||
| S2pengy |
I have 2 S2's with close to 50,000 miles on each. I have had to replace the front isolators twice on each bike due to horzontal tears on the side of the isolator as seen on the lower portion of the isolator mount, and always in front. While I would love to say it was 2 up driving it isn't, also I don't believe mileage is a factor... I have to think it is age each time they were about 3 years old... The older -79B style is available at alot of aftermarket shops because of the HD usage | ||
| Jimidan |
With mine, the continuing failures could easily be horse power and torque related. I doubt that these things were over-designed to handle the additional power of an 88", and riding two up with luggage only exacerbates this by stressing the front even more (the engine IS a stressed member). My theory is that the additional weight definitely puts more load on the front of the isolator (I can see it when weight is added to the bike) which compresses the rubber and restricts its ability to move. That coupled with the engines movement in the vertical plane is enough to wreck havoc on the isolator. The old ones had a metal band inside that only allowed so much compression, however the new one that just grenaded on my bike seems to be just the vulcanized rubber with a metal sleeve, which is where it broke-up more severely than in the past (see Hugh's photos above). Like I said before, with the old design, I could remove the isolator and turn it around to get double duty as the rear of the mounted isolator has little stress since it doesn't appear to be supporting much of the weight of the engine and bike. With this new design, it looks like there isn't any material left on the back side once it destructs...the whole sleeve in the center is broken loose. I know that American Sport Bike had at one time offered an aftermarket isolator that used a polyurethane bushing (I believe), but I don't think they proved to be any better, as they dropped them after a short while. It also transmitted more of the paint shaker's vibration into the frame. These isolators may make the S2 obsolete prematurely after HD/Buell stops making them, especially since they no longer share a part number with the Hogs. That would be a shame to have to park (part out?) my steed because I could no longer get this part. I guess that is just a matter of time, since like I said, I doubt if any Buell engineers are losing any sleep over this problem. I have looked in my Jireh Cycles and J&P Cycles big books and have not found any aftermarket isolators for HOGs, but that may be an option. Are there any other vendors out there that sell them? jimidan (Message edited by jimidan on June 09, 2006) | ||
| Mikej |
"I doubt if any Buell engineers are losing any sleep over this problem." There are Buell engineers who also own S2's, if we're affected then they're affected. I'm thinking there will be an eventual mod to utilize whatever isolators are available once the current production is deemed obsolete. | ||
| Whodom |
I'm thinking there will be an eventual mod to utilize whatever isolators are available once the current production is deemed obsolete. Out of curiosity, how different is the XB front isolator? | ||
| Sarodude |
First - a comment about the Blast Heim joints... Someone mentioned the Blast doesn't have the upper front Heim joint. In fact, year 2000 Blasts DID have it. In later years, it was dropped. An Anonymous poster mentioned that it was dropped because it transmitted more vibes and the handling differences it made likely did not matter to the target demographic. So, at least with the Blast, it seems the factory saw fit to just omit that joint with no apparent further modification to the bike. -Saro | ||
| Oldog |
this looks like a golden opportunity for an engineer [ M.E. ] to make an improvement to the breed any way to make a front iso with a replaceable rubber biscuit? | ||
| Ezblast |
Or a stronger urathaine/rubber re-enforced compound? GT - JBOTDS! EZ  | ||
| Whodom |
I'm an M.E., but designing a new front isolator would be way over my head. Using a stronger/re-enforced material might defeat the purpose of having an isolator. It's probably a pretty big challenge to design an isolator with the required degree of "give" that's also strong enough to support the weight of the bike, rider, and luggage. I was wondering about using an XB front isolator. I don't have an XB handy to examine but I did find some photos here: http://www.badweatherbikers.com/buell/messages/32777/56570.html Looks like the front mount and isolator are very different from the tubers and it would take a lot of effort to adapt to a tuber. Still, it's a thought. Dave & others are checking with the factory to see if this is an "issue" or not. I'm interested to hear what they find out. | ||
| Tramp |
cut the old rubber from the iso (two bisecting cuts), make a little duct-tape dam around the top and bottom, and then, two words: Shoe-Goo... pretty dense compound when set..... | ||
| Oldog |
Hugh how does the iso move Up and down? I thought that the tie bars restrain left / right motion, the motor hangs from a bolt in the front hanger could a sandwhich of steel and rubber do that job so that the iso is repairable? how would you describe the loading? compression or tension? | ||
| Whodom |
Olddog, You're right- the tie bars restrain the engine/tranny's movement to a vertical plane. It can move up and down or back and forth, but not side-to-side. I'd say the load on the front isolator is generally downwards. The weight of the bike on the rear wheel pushes upwards, and the engine/tranny attempts to pivot around the rear isolators pulling downwards on the forward isolator. More weight on the bike = more downward load on the forward isolator. The rubber is mostly in shear (not tension or compression). IIRC, that's sort of a fundamental requirement for making an engine mount like this work properly. You could do a repair with with a rubber/steel sandwich, but it probably wouldn't isolate the vibration nearly as well as the stock mount. Tramp's idea probably isn't bad, but I'm not sure how well Shoe-Goo (or other similar stuff that's available) would "bond" to the metal parts of the mount, and that's a pretty important requirement for whatever material is used. | ||
| José_quiñones |
Saro, I did not know that about the 2002 blast, but it helps to confirm what I found, on my S3, removing that 'fourth' link reduced the vibration felt at the handlebars, at the cost of lower 'torsional rigidity' but most people won't notice that. It think it's the shear force of the passengers weight transmitted up through the isolator is what kills them, or the combination of weight and hitting a major dip/bump can also do it. The only thing you need to be able to use the 79c HD part number would be a smaller diameter bolt. how it would hold up is another matter. HD redesigned the front mount on the VROD for the 04 model year too, so it's not just a Buell issue. | ||
| Jimidan |
I have used Shoe Goo and other similar glues to patch the horizontal plane tears in my old style isolators before I turned them around and used them again. By the time the isolators tore again, the glued tear was torn again too. After examining the way they are made, I do not think that the new style isolators will work at all. I question whether it is even worth the effort to try and get the Mo.Co. to warranty these things. It takes me about an hour to change these out on my S2, if I am home...which I never am when they break. The good news is that I have ridden 1100 hard miles through the mountains with luggage and it still didn't damage my bike too much. The front cast aluminum engine mount was hitting the "V" shaped heim joint support and it could cause a major failure in that bracket I guess. I only do power wheelies that lets the front end down easy, so there is no big hit on the front isolator. I would think that wheelies would be terrible on that isolator...it is hard to say how much sheer force there is on it with a hard landing. I am still looking for an aftermarket isolator with the designed bolt size hole in it, but I haven't seen one yet. Any ideas on a vendor? jimidan | ||
| Whodom |
Jimi, Another idea would be to drill out the steel bushing in the HD mount to take the proper Buell-sized bolt, if there's enough meat to do it. I'm pretty sure I've seen "generic" rubber mounts similar to this in industrial supply catalogs; there's bound to be something out there that would work. Whether it would work better than the Buell part is another question. | ||
| Henrik |
Back in my FXR days there were one or two aftermarket companies making rubber mounts. Not sure where to look these days, but it may be worth a search. Henrik | ||
| Jimidan |
Hugh says, "Another idea would be to drill out the steel bushing in the HD mount to take the proper Buell-sized bolt, if there's enough meat to do it." It would be a bit of a problem drilling it out considering the sleeve is surrounded by rubber (heat and the bit would chatter like a mo'fo'). I can not understand why the MoCo would redesign it worse than the original? Jimidan | ||
| Shanetbolt |
I'm a little worried now, on average how long do these isolators last on a bike in miles or time? I have a 99 S3 with 50K on the clock and all engine isolators are original. I occasionally look at the swing arm isolators but never thought to look at the front one. I'm planning a trip to Sturgis and would hate to have a failure at that time. | ||
| Whodom |
Jimi, It is hard to understand why HD would go to a mount with a smaller bolt than original. How much difference is there in the diameter? No doubt you're right about the difficulty in actually drilling it out, but I'll bet you could still bore out the HD mount on a lathe without much trouble. OTOH, unless you've got your own lathe, the cost and effort wouldn't be worth it. Shane, I'd say yours have lasted much longer than usual. Hard and/or two-up riding probably accelerates their failure. If you haven't done much of that, you may be OK. The front one is a fairly easy job to replace; the back ones are a little more involved. Neither is the kind of job you want to do far away from home in a motel parking lot. | ||
| Tramp |
shane- go ahead and replace the isos, it's a snap to do, and your scoot will feel strangely tight again. i rode my originals well past 200,000 miles, and believe me, the last 50,000 were sheer insanity. likely the last 100,000. just replace 'em. call dave s. and do it before sturgeon | ||
| Daves |
Shane I agree with Tramp, replace them before you head to Sturgis. 50,000 miles is a lot to get out of the rears | ||
| Jimidan |
It has always been a mystery why some Buells (riders?) get great service out of the isolators and some eat them. I know riding style has a lot to do with it in some cases. Stunting would seem to be the worst thing you could do to a front isolator. Dropping the front end hard during a wheelie event would put thousands of pounds of sheer force on the front isolator. Fun? I don't think so. There is also a wide deviation between those bikes that eat the rears but not the fronts, and vice versa. My bike has the original rears installed at the factory in 95-96, and have over 40 miles of 88" torque on them. I will replace them when I change engines this time around, just for safety's sake. But the front ones have always been the problem. The S2 is famous for being easy on the rears. S1's were famous for being hard on the rears. Why? If you account for extreme riding techniques and stunting, and remove them from the pool, I wonder what the other factors would be that cause this phenomena? Could we take a pool here? As unscientific as it may be, it may shed some light on it. I am sure that it would be at least as scientific as the "poll" taken by my dealership's service manager, when he determined that there was a "bad batch" of isolators based on the number of replacements that they were having to do. I would contend from the comments made on this site to date that there was a bad batch made...and they include all of the new types. So, could we get you guys to post your experiences with your tube frame bike's isolators? I will set up a separate thread with the title "Tube Frame Isolator Survey", and if you are a stunter who likes to do wheelies, indicate it when you respond. Thanks, jimidan | ||
| Buellistic |
HOW OLD IS THIS SAID "BAD FRONT ISOLATOR(miles and years) ??? WHAT IS THE "PART NUMBER" FOR THIS "ISOLATOR" ??? | ||
| Jimidan |
The failed isolator was purchased back in the fall and sat on the shelf until right before I went on my trip to Summit Point. After only 400 miles, it was torn, but I continued to ride on it for the rest of the trip which was another 1100 miles. It is shredded up pretty good and allowed some contact between the frame and the front engine support bracket that bolts to the head. According to Dave in his earlier archived post the part number is 16207-79C, with the new number L0501.2. I don't believe that the addition of a heim joint stabilizer will prevent the tearing problem as it does little to stop the vibration in the vertical plane. The isolators are tearing first in the vertical plane only. | ||
| Whodom |
Jimi, I had a thought on the general failure of front isolators (not directly related to the alleged "bad" batch). IIRC correctly from changing out my front isolator, the "D" shaped washer that sits on top has a fairly sharp edge on the front side (the straight leg of the "D"). I wonder if grinding/filing a radius on this edge where it contacts the isolator would lessen the tendency for the isolator to tear? It seems that most of them fail along the line where the washer contacts the isolator. | ||
| Buellistic |
jimidan: My 97 has a FRONT ISOLATOR PN 16207-79B which up-dated to 16207-79C which is used on BIG TWINS(the rear isolators can be used off the BIG TWINS as long as you do not ride double)and of course the "BUELLschitte" PART NUMBER L0501.2 ... | ||
| Jimidan |
I was just at my local dealership again today and they had the full compliment of isolators for us to compare. The new isolator L0501.2 has been changed significantly for the big twin application, and has a flat washer molded into to the TOP and has a smaller bolt size. This isolator will not work with tube frame Buells, regardless of the bolt size, because the washer is not cut in the "D" pattern so it would hit the steering head. Under the same number, L0501.2, there is a Buell only isolator that looks identical to the 16207-79B that I purchased 9 months ago. It has the same markings in the rubber portion and the same bolt size sleeve. It is made to work with the "D" washer. The service manager said that my only choice was to buy another Buell isolator just like the one that failed in 400 miles, as he was not authorized to replace mine under the 90 day warranty. I chose not to buy another one as I still have a much older one on the bike now (those parts on the shelf come in handy sometimes) that is holding up pretty well...and wait to see if Buell comes up with anything to replace ours in the future. They (HD) sure went the extra mile to fix the isolator for the big twins though. It looks like a very substantial piece. WHodom sez: "I wonder if grinding/filing a radius on this edge where it contacts the isolator would lessen the tendency for the isolator to tear? It seems that most of them fail along the line where the washer contacts the isolator." It could not hurt, as my new model one was torn in that area too. But in the past, there was only a horizontal tear along the front top where the rubber separated from the metal band coming up from the flange. It is worth a shot...I will try that too. jimidan | ||
| S2pengy |
J&P cycle does have a replacement available for the front isolator just like the 16207-79B... No markings and package sayes made in Taiwan. Price is $19.99 part number is 4300140. Several outfits have poly 3 piece versions available but they run around $100.00. I hope I didn't step on too many toes by posting this.... |
