broken countershaft bolt

[woodsguy]

On a 2022 Honda CRF450, going over it last night saw the bolt was backed out. In checking it was snapped into. No idea how I got lucky the sprocket didn't come off while riding. I did replace the sprocket a few months ago, but haven't tightened it since then.

2 questions, any idea what happened?
How to remove without splitting the cases?

 

[bwdmax]

Did you use loctite when you changed your sprocket?

I would use a left handed drill bit to try and remove the piece of bolt remaining in the counter shaft. In the even that you used loctite you may need to apply some heat to get it to release.

What happened? Who knows? Bad bolt? Did you inspect or change the spring washer when you changed the sprocket? There is a shoulder on the bolt that centers the collar (part 17) and washer (part 31) sometimes during assembly if these drop behind the shoulder instead of center when you tighten the bolt it could side load the bolt. Really hard to say.

 

[budzrex]

Rob, can you get to the exposed bolt? if so set a nut on the exposed bolt and tack weld inside the nut to secure it to the exposed broken bolt then just
use a wrench and back the bolt out

 

[Johnf3]

That bolt will come out fairly easy with a left hand drill bit most likely. I have extracted many broken countershaft bolts like that. It will not have any tension on it and will screw out easy. Drill straight in the middle with a small bit. Increase size as needed.

Extracting broken bolts and screws is a bit of an art form. My buddy owns an auto repair shop and he is a broken bolt extracting savant. I have learned a bunch from him. Drill straight, take your time and have good drill bits to start.

I generally do not recommend any type of extractors because they break off and then you have a much bigger problem, but in this case with as easy as that bolt will be to remove with no tension on it (even with loctite if that is the case) an extractor will work too.

If you were near we would have it out in 10 minutes.

 

[woodsguy]

This

Did you use loctite when you changed your sprocket?

I would use a left handed drill bit to try and remove the piece of bolt remaining in the counter shaft. In the even that you used loctite you may need to apply some heat to get it to release.

What happened? Who knows? Bad bolt? Did you inspect or change the spring washer when you changed the sprocket? There is a shoulder on the bolt that centers the collar (part 17) and washer (part 31) sometimes during assembly if these drop behind the shoulder instead of center when you tighten the bolt it could side load the bolt. Really hard to say.

Spring washer not new.
Don't remember but sure there's locktite involved.
Again don't remember but it's obvious it needed to be centered so I think so.

 

[HiSPL]

As you are doing the left hand drill bit thing, it would help to blow compressed air into the hole to clear the chips you'll be making. You don't want a chip to get caught in the threads ruining an otherwise easy bolt extraction.


We had a weird CS issue this week too. My son has an 05 CBR600rr and the transmission/CS area started clicking like the chain was worn, but the chain and sprockets were fairly new, installed by the PO. We couldn't figure it out. It would click when you properly adjusted the chain slack. If the chain was really loose it wouldn't click.

As a last ditch effort to figure it out we removed the CS sprocket to turn the CS by hand, and wouldn't you know it the sprocket nut was put on by a 900 pound gorilla with a cheater bar! When we reassembled and torqued it to the proper 40 ft/lbs it was fine! no clicking anymore!

I have no idea how the improper torque caused the clicking, but it sure is gone afterwards!

 

[woodsguy]

As you are doing the left hand drill bit thing, it would help to blow compressed air into the hole to clear the chips you'll be making. You don't want a chip to get caught in the threads ruining an otherwise easy bolt extraction.


We had a weird CS issue this week too. My son has an 05 CBR600rr and the transmission/CS area started clicking like the chain was worn, but the chain and sprockets were fairly new, installed by the PO. We couldn't figure it out. It would click when you properly adjusted the chain slack. If the chain was really loose it wouldn't click.

As a last ditch effort to figure it out we removed the CS sprocket to turn the CS by hand, and wouldn't you know it the sprocket nut was put on by a 900 pound gorilla with a cheater bar! When we reassembled and torqued it to the proper 40 ft/lbs it was fine! no clicking anymore!

I have no idea how the improper torque caused the clicking, but it sure is gone afterwards!

The thinking is I had this too tight and took the spring tension out of spring washer. Or something broke this piece and let bolt get cockeyed. This piece is pretty dirty, it's been broke a while.

 

[woodsguy]

@GSTJOHN got the broke piece out but shop doesn't have. So still out of luck this week. But blessed he got it out. Thanks!!!!

 

[woodsguy]

Cycle Shack got part overnight for me so we got to ride Thursday after all!
Also pretty sure it was my fault, there's 2 pieces the bolt goes through, pretty sure I had them backwards, which caused the part you see broke here to fail. Which in turn put the bolt in a bind till it snapped. Lesson learned and thankful I found it at home.

 

[sandman]

@GSTJOHN to the rescue,…. Rob that is awesome. I had a similar thing happen on my Honda 450. As you already know the washers must be in correct orientation and use blue Loctite.

 

[woodsguy]

@GSTJOHN to the rescue,…. Rob that is awesome. I had a similar thing happen on my Honda 450. As you already know the washers must be in correct orientation and use blue Loctite.

Know that now.

 

[woodsguy]

Of course I THOUGHT it was right last time.

 

[chiricahua]

Got a few out with a left turn extractor after drilling.
Do not over tighten. Bolt is pretty soft.