Author |
Message |
Bushwick_bill
| Posted on Monday, February 13, 2006 - 04:52 pm: |
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I'm new to the Buell World and have recently purchased a 98 S1 which has a cracked engine case at the lower shock mount bolt. There is a Pic posted at the XLForum.net in the Buell forum. I have searched the archives, but haven't found much on this problem. I'm tempted to try to strap, or brace the mount to the rear of the engine for extra support. I'm just curious if this has been much of a problem with the tube frame Buells? Thanks, Boyd |
Whodom
| Posted on Monday, February 13, 2006 - 06:15 pm: |
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Bill, That's a weird one. I'd guess that came from the bike being wrecked at some point. The normal action of the shock, since it operates as a "pull" spring, would never make the case crack like that. I.E.- the normal load on that bolt is towards the back of the bike, not towards the front. I'm sure it would be best to grind it out and have it professionally welded, but I can't see how riding the bike is putting any load on that bolt which would tend to open the crack wider. |
Bluzm2
| Posted on Monday, February 13, 2006 - 06:21 pm: |
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That's a nasty crack! The previous owner must have REALLY over stressed it. That is not a common failure mode. In fact, I'll bet this is the first most have ever seen. I'd be tempted to pull the motor (your going to have to do it anyway) and have it welded. It would have to be done by someone who really knows their stuff as the gasket surfaces must not warp from the heat. I lifted the picture from the XL files, hope they don't mind. I don't think I'd use the JB Weld option. It might work but I'd be worried about structural strength. Brad
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Josh_
| Posted on Monday, February 13, 2006 - 07:12 pm: |
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I think you'd have to pull the motor to weld it, I have not heard of/seen that before. While you're at it, update the exhaust bracket. Buell fans should note the exhaust tie bar also. |
Buellistic
| Posted on Monday, February 13, 2006 - 07:28 pm: |
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IMO the bolt was over tightened !!! |
Akbuell
| Posted on Monday, February 13, 2006 - 07:38 pm: |
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Given the stresses involved in that area, I'm with Buellistic, the bolt was WAY overtightened. The cure, however, remains the same: complete disassembly, and a very professional re-weld and re-cut the threads. No other real choice; now that the crack exists, vibration and heat cycles will only cause it to grow, IMHO. |
Bluzm2
| Posted on Monday, February 13, 2006 - 08:51 pm: |
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Aren't the top and bottom bolts? I don't think you could crank a bolt down that tight and have it crack the case with out breaking first.. Unless the face of the shock mount was not flat. Weird any way you look at it... |
Fusa21
| Posted on Monday, February 13, 2006 - 10:29 pm: |
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I'll go on record here as being the first to make this happen to a Buell. I raced one in '99 at Daytona. Nearly highsided out of turn 4... in the grass before the West Horseshoe there's a guard rail...I saw it coming, decided to bail off, and the bike hit the wall at 50-70 mph. I cracked the frame right at the headstock, pushing the front wheel into the oil filter/engine cases. The bike also did a cartwheel after impact. That must have given the shock mount enough force to crack the cases in that exact spot. Luckily we sent the cam side case 1/2 to a welder who machined out the hole and built up a new one. The fix worked great, but you definitely want the cases completely torn down for the fix. good luck. |
Bushwick_bill
| Posted on Tuesday, February 14, 2006 - 05:56 am: |
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Thanks all! I feel better knowing that it is an isolated case anyway. The case looks even worse from the side. I will probably try to have them repaired, but I've picked up a set of cases from Nallin that have already been machined for the 88" kit. This website has been a valuable resource already. Thanks, Boyd |
Tbolt_pilot
| Posted on Friday, February 17, 2006 - 08:05 pm: |
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Bill, Yeah, thats an odd crack. And like Josh says above, swap that exhaust bracket and keep an eye on that tie bar...or more specifically, the slotted mount on the pipe. Mine isn't in use anymore. Anywho, If you swap cases due to this crack situation, what are your plans for the bad case? Reason being, I am kinda in the market for a 'junk' case and jugs for mock-up purposes. All I need is the mounting points in the right places. But I also want to go inexpensive so if you can get $$ for it from someone that will repair & use it then go for it. But just keep me in mind. Thanx! Dave |
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