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Discussion Starter · #1 ·
Hi All, thanks for taking the time to read.

Just noticed this crack and push through of a lower case bolt behind the gear shift/main drive chain case:

Auto part Fuel line Engine Automotive engine part Metal Auto part Disc brake Engine Vehicle brake Gear

Can't see the bolt and there are no loose pieces. I don't know how long it's been like this for as the bike is new to me and I have yet to ride it.

Thoughts on what to do? I REALLY don't want to have to take the engine out and split the cases. One thing I thought about, and I may be way off, was perhaps using some JB Weld around the break (after thoroughly cleaning it).

Thanks Fellas.
 

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First things first.
The bike didn't come this way from the factory. Something's changed; either the bolt in question is missing a washer or spacer of some kind, or it's been changed out for a longer bolt (whether it's been replaced or just mixed up with another lower case bolt that's too long). In any case, address this first. Case bolts need to be torqued to spec. If the bolt is distorting engine case metal, it isn't exerting the proper clamping force on the case.

Once you've got that sorted out, then yeah, you need to patch this. Cleaning the area thoroughly (and I'd be inclined to remove some of the surface around the damaged area, just to be sure there's a good surface for adhesion), you could patch it up with some JB Weld. A proper fix would be to disassemble everything and have the area TIG welded, but I'd try the JB Weld approach first.
 

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That's not from a bolt it is from someone not getting the locating pin seated where it was supposed to be and the pin pushed through the case.

Means taking the engine out and splitting the cases to get everything back in place properly then repair the damage. Some have the case welded others use epoxy.

This can not simply be repaired by slopping epoxy on top, parts are not aligned properly inside the cases.
 

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Discussion Starter · #4 ·
Thanks Old Putz (great name btw) and Boomer for the replies. That's what my gut said too . . . but it's getting so nice out up this way that my brain wants to ride ASAP!

Looks like I'm pulling the engine out. :roll:
 

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I would just run it ,for the time being. The bearing race isn't moving in the case, it's clamped tight between the case halves. It isn't going to break anything else by riding it now, you can fix it when bad weather comes.
 

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Discussion Starter · #6 · (Edited)
Damn it Mike! ;)

What to do, what to do . . . .

Could the previous owner put in a longer locating pins than he was supposed to? I can't understand how else it could have broken through. IF I did leave it as is I should probably do something to prevent any oil getting through that passage - there does not look like any had been, but better to be safe than sorry.
 

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Dab some RTV over the crack to keep the oil from leaking and go ride it.
 

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I encountered a similar situation is past winter. PO busted the upper case and everything was sitting a little off and causing shifting issues when hot. Like mike said, what's done is done. I also happened to have a bad head gasket leak so that's why I pulled it. May as well run it and plan to rebuild sooner than later.
 

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I will tell you that it is possible for the bearing cap to move outward under the worst case scenario, I've seen it happen on the other side on the end of the countershaft behind the clutch when the locating pin pushed through the case. It might not, but if it does it will push the clutch rod seal out with massive loss of oil all at once
 

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Discussion Starter · #11 ·
I will tell you that it is possible for the bearing cap to move outward under the worst case scenario, I've seen it happen on the other side on the end of the countershaft behind the clutch when the locating pin pushed through the case. It might not, but if it does it will push the clutch rod seal out with massive loss of oil all at once
Thanks Ancient Dad. I don't get how the locating pin could have pushed through like that unless the PO used a longer/wrong pin.

Cheers
 

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^^^yes, I wouldn't consider it easy to miss if you've done any Honda engine bottom end work before, but we've seen quite a few instances where someone put the shafts in the upper case and didn't have the roller bearing cap(s) aligned with the pin(s) in the bearing location in the upper case. The shaft/bearing cap will stick up slightly if not located over the pin properly, and it would seem to me that when the lower case half goes on it would not sit flat and should catch the attention of the person assembling it, but to the lesser-experienced eye it could get by... and then tightening all the bolts leads to the pin getting pushed through the upper case
 
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