Alternator rotor bolt is crazy hard to turn

[Guest]

I have a 79 GS750 and I'm currently in the process of tearing it down for (hopefully) a cafe project. I'm disassembling the engine and the bolt holding the alternator rotor on is super tough, trying to see if this is normal or if I'm destroying something.

The bolt is super hard to move, even with a large breaker bar it's taking quite a lot of effort to turn. I have it backed out between a half and three quarters of an inch and the resistance is still super heavy. I finally stopped when it made a strange creaking noise while turning. I'd love to hear it's just on with a ton of thread locker, but wanted to make sure I'm not breaking anything stupid or shearing the damned thing.

I have a manual and it doesn't mention anything about this bolt being crazy, so I'm getting worried. Any help or advice would be appreciated!

[Baatfam]

Don't have an answer, but I do have a question.

Why are you tearing the motor down?

[Rich82GS750TZ]

Like Bob mentioned, unless somethings wrong with your starter clutch on the back side of the rotor, or you’re splitting the cases, why would you need to take the rotor off?

Anyway, I’m sure it’s covered in the Service Manual. You can download one at BikeCliffs Website.

[tom203]

Not clear how you are holding rotor while the breaker bar has a go at nut....but I would just get an impact wrench to remove the nut, then get a rotor puller to “slide” the rotor off the crank. The right tool will cost maybe $20.....avoid banging on rotor.

[chuck hahn]

Use an impact. It's loctited in. And you loctited it when you reinstall it or it will come loose

[Rijko]

try to turn it back a bit, crushing and spread any junk caught in the threads that way.
Use WD40 to help lubricate and wash clean the thread.
Hopefully that makes it turn easier.

[RogerL]

I'm in the same boat. I have a 650E that I'm stripping the motor down for a full rebuild and cleaning. My plan wass to hit it with the impact gun. Would like to knnow if this is reverse thread or not. I'm leaning towards not, given how the wrench and special tool are shown in the picture of my service manual.

[tom203]

It’s a standard right hand metric thread. After you remove this bolt, you’ll need a 16 mm to thread into rotor itself and push the rotor off the crankshaft ....impact tool is a must.

[GregT]

The bolt is long enough that there is a substantial portion of thread sitting exposed inside the hollow crank end. If it's loctited all the way down the thread, once in, the loctite sets on the exposed thread and can be a right pain to get out through the threaded hole.There's no way to get any WD40 or similar into the end cavity so it's just simple persistence and poassibly a little heat.An impact gun does help.When re-installing, only put loctite on about half the thread - at the head end of the bolt. This is the end that actually does the work.