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| techtalk:ih:engmech09f [2021/06/10 20:39] – created hippysmack | techtalk:ih:engmech09f [2023/12/27 22:12] (current) – hippysmack |
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| ====== Broken / Cracked Rear Mounts ====== | ====== Broken / Cracked Rear Mounts ====== |
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| | Originally, the rear motor mount was made of steel and had 4 bolts in the top. ((piniongear at HD Forums https://www.hdforums.com/forum/ironhead/633728-ironhead-rear-motor-mount-stud.html)) \\ |
| | Later it was made of aluminum and prone to cracking. The steel mount will never crack. \\ |
| | The first aluminum mount had 4 bolts in the top. Later the mounts had only 2 bolts. \\ |
| | Aluminum mounts are going to crack. If you have a brand new replacement mount in hand right now, it will crack. \\ |
| | Should your mount be a steel one, then it is worth installing. But, the cracks do not present a real problem though. \\ |
| | That is the good news. \\ |
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| | Sometimes the mount cracks all the way across as in the pics below. \\ |
| | Whilst many of them tend to crack, some only crack so far and then stabilize. ((simonster123 of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/86472-stock-vs-pingel/page2?t=670768&page=2)) \\ |
| | Unless it's completely cracked through or flexing like mad, you can run it and monitor whether or not it gets worse. \\ |
| | So it's not necessarily a problem that has to be fixed depending on how badly cracked it is. \\ |
| | However, it does reduce vibration to repair or replace. \\ |
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| | And even if the aluminum mounts are installed correctly, they will still crack. They seem to crack worse after welding. ((Dr Dick of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/126465-rear-motor-mount-help/page2?t=1283746&page=2)) \\ |
| | It may be best to score a 57-60 steel mount (a 52-56 k model mount will work too if you ain't got a kickstart) and cut it to mimic the -67 mount. \\ |
| | You can try to have the crack welded as in the pics below. \\ |
| | You can also replace it with an aftermarket mount. Pingel has a high reputation as an aftermarket alternative. \\ |
| | See [[techtalk:ref:engmech09#pingel_rear_motor_mount|Pingel Rear Motor Mount]] in the REF section of the Sportsterpedia. \\ |
| | The heavy aftermarket works but it takes up more room and you gotta screw around with the lower oil tank mount if you're working on a 70-78CH. \\ |
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| | This one is cracked all the way across. \\ |
| | {{techtalk:ih:engmech:cracked_motor_mount_1_by_jsandidge.jpg?direct&300|}} ((photo by jsandidge of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/198233-cracked-motor-mount/page4?t=2074969&page=4)) {{techtalk:ih:engmech:cracked_motor_mount_2_by_jsandidge.jpg?direct&300|}} ((photo by jsandidge of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/198233-cracked-motor-mount/page6?t=2074969&page=6)) \\ |
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| | This one is only cracked for a small distance. \\ |
| | {{techtalk:ih:engmech:cracked_motor_mount_on_73_ch_1_by_killer_ch.jpg?direct&300|}} ((photo by Killer CH of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/130889-rolling-basket-case-saga-now-it-s-the-rear-motor-mount?t=1384261)) {{techtalk:ih:engmech:cracked_motor_mount_on_73_ch_2_by_killer_ch.jpg?direct&300|}} ((photo by Killer CH of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/130889-rolling-basket-case-saga-now-it-s-the-rear-motor-mount?t=1384261)) \\ |
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| | This one from a 68 XLCH has been welded. \\ |
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| | {{:techtalk:ih:engmech:welded_rear_motor_mount_on_68_xlch_pic_1_by_kennycoulter.jpg?direct&300|}} ((photo by kennycoulter of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/117858-wiring-placement-pictures-or-diagrams/page3?t=1139862&page=3)){{:techtalk:ih:engmech:welded_rear_motor_mount_on_68_xlch_pic_2_by_kennycoulter.jpg?direct&300|}} ((photo by kennycoulter of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/117858-wiring-placement-pictures-or-diagrams/page3?t=1139862&page=3)) {{:techtalk:ih:engmech:welded_rear_motor_mount_on_68_xlch_pic_3_by_kennycoulter.jpg?direct&300|}} ((photo by kennycoulter of the XLFORUM https://www.xlforum.net/forum/sportster-motorcycle-forum/sportster-motorcycle-era-specific-and-model-specific/ironhead-sportster-motorcycle-talk-1957-1985/117858-wiring-placement-pictures-or-diagrams/page3?t=1139862&page=3)) \\ |
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