Ducati.org forum banner

1 - 3 of 3 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter · #1 ·
98 st 2 with 35k on it. Top bolt of rear motor mount had broke when? i dont know, maybe was that way when i bought bike from po. Anyway I rode bike for year or maybe 10K miles, never noticed anything wrong. Being on the plus side of 50, I have learned to slow down a little and enjoy the scenery and such , cough cough, bs! ok i just dont push as hard as i used to, lol Well one day i happened to see that the little black plastic cover on a hole in the frame was missing so I looked in the hole and saw bolt was broken. Case was still in good shape. So ordered new bolt from local dealership which had to order it from Italy. "oh, never had to order that bolt before" said the parts guy sounding very suspicious. New bolt came in a week or so later and I installed it that night.
Anxious to go for a ride, I was backing out of my driveway, hadn't yet started the motor, and Bang! The bolt head from the bolt that is in the next hole up on the frame, comes shooting out and lands on the ground That bolt being the one that goes through the center of the rear shock pivot arm.
Put the bike on center stand and grabbed the rear wheel and lifted up and noticed about 1/2" of slack.This cant be good I thought. Closely watching while my friend did the same lifting and I could see that all the slop was located in the now broken bolts hole. Appears to have egged out a fair amount from all the miles put on while the other bolt was broken. Im thinking of drilling out the hole to next size or two up, whatever it takes to remove the slop, and putting in a fresh new bigger bolt. yes I have read much since on the broken bottom bolt and now know why parts guy had such a sarcastic tone and am aware of Nichols and all the different types of bolts to use or not use, rolled threads vs. machined, etc... My concern is will it be possible to drill new bigger hole while the bike is on centerstand , with the rear suspension supported from straps to the rafters to keep everything aligned while bolt is out of hole and drilling is being done or should all the parts be removed off bike and make up some kind of jig to keep it all in alignment? Certainly it is a must to be in alignment with the top rear motor mount bolt, seems as they are related since the one broke immediately after the other was repaired.
Thoughts? Tips? has this happened to anyone else? Am I overlooking something serious? any help is much appreciated!
 

·
Registered
Joined
·
207 Posts
98 st 2 with 35k on it. Top bolt of rear motor mount had broke when? i dont know, maybe was that way when i bought bike from po. Anyway I rode bike for year or maybe 10K miles, never noticed anything wrong. Being on the plus side of 50, I have learned to slow down a little and enjoy the scenery and such , cough cough, bs! ok i just dont push as hard as i used to, lol Well one day i happened to see that the little black plastic cover on a hole in the frame was missing so I looked in the hole and saw bolt was broken. Case was still in good shape. So ordered new bolt from local dealership which had to order it from Italy. "oh, never had to order that bolt before" said the parts guy sounding very suspicious. New bolt came in a week or so later and I installed it that night.
Anxious to go for a ride, I was backing out of my driveway, hadn't yet started the motor, and Bang! The bolt head from the bolt that is in the next hole up on the frame, comes shooting out and lands on the ground That bolt being the one that goes through the center of the rear shock pivot arm.
Put the bike on center stand and grabbed the rear wheel and lifted up and noticed about 1/2" of slack.This cant be good I thought. Closely watching while my friend did the same lifting and I could see that all the slop was located in the now broken bolts hole. Appears to have egged out a fair amount from all the miles put on while the other bolt was broken. Im thinking of drilling out the hole to next size or two up, whatever it takes to remove the slop, and putting in a fresh new bigger bolt. yes I have read much since on the broken bottom bolt and now know why parts guy had such a sarcastic tone and am aware of Nichols and all the different types of bolts to use or not use, rolled threads vs. machined, etc... My concern is will it be possible to drill new bigger hole while the bike is on centerstand , with the rear suspension supported from straps to the rafters to keep everything aligned while bolt is out of hole and drilling is being done or should all the parts be removed off bike and make up some kind of jig to keep it all in alignment? Certainly it is a must to be in alignment with the top rear motor mount bolt, seems as they are related since the one broke immediately after the other was repaired.
Thoughts? Tips? has this happened to anyone else? Am I overlooking something serious? any help is much appreciated!
Sure wish we had some pics before we talk about this...
 

·
Registered
Joined
·
18 Posts
Firstly, you are really lucky that it didn't break the frame or the crankcase in that area. They usually do. Later bikes came with a 12mm bolt that is obviously stronger. You can drill the frame and cases in situ and install it but obviously you'll need a long drill bit to do it. Don't be tempted to update the front one as there is a crankcase joint dowel which will make it damn near impossible to fix it without splitting the cases and machining. I've never seen the front one break or the suspension rocker pivot bolt break for that matter. I think you were just unlucky there. I would not recommend Nichols bolts for this especially with the large, heavy nuts. I have seen hairline cracks develop in the frame tube that the rubber plug fits into after fitting those bolts. Not saying they're bad---just my observations on other bikes. I've never seen those cracks with the OEM hardware.
 
1 - 3 of 3 Posts
Top