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Discussion Starter #1
What I thought would be a quick chain and sprocket change has now turned into a nightmare. I managed to remove the rear sprocket after many hours of frustration with pb blaster, putting the nuts back on has been impossible.

I tried using a 6mm hex 3/8" drive and a 3/8 to 1/2 adapter on my torque wrench with a 17mm open wrench to try to get it to 65 newton-meters. But the ******************** bolt strips every time. Whose bright idea was it to have a hex bolt why not a regular 6 point?!??!??! And I can't get a socket onto the nuts on the other side because the parts of the wheel sticking out is directly in line with the nut meaning nothing can fit between them. What am I missing?

Icing on the cake: the fixing plate does not fit on these front sprockets I got, the holes are completely misaligned for the bolts, but I'll just order an OEM to fix this
JT Sprockets JTF1321.14 14-Tooth Steel Front Countershaft Sprocket

Please send help
 

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Ive done this job three times now on 250 & 300R's. The secret is to put the torque wrench back in the drawer.
Not everything you read is correct. They only need to be done up tightly by hand. If you are still concerned about them coming loose then put a drop of loctite on each thread before assembly.

If you dont like the socket head bolts then change them for six pointers, they dont have to be socket heads. I changed the OEM bolts on my 300R to Aluminium six pointers which have a max torque of about half what you quoted. Never came loose.

The point I'm trying to make is that everything is only a guide or a recommendation, there's room for your own interpretation and modification.
 

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Best way for removal is an impact with the hub out of the wheel and in a vice. I was able to get all but one of mine loose with a breaker bar and careful application of torque, but one did eventually round slightly and I had to get creative with vice grips and an impact wrench on the nut.

If they are stuck, you can drill out the aluminum bolt heads from the center of the hex, and then replace them. It's relatively soft metal and doesn't take much time. You just have to be careful to not damage the hub.

Upon reinstall, they don't have to be that tight as has been stated previously. The nuts are locking nuts with blades that grab the threads as they're torqued down. No loctite or overtightening is needed with them, but some blue loctite can give you a little piece of mind.
 
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Discussion Starter #5
Thanks everyone I think the consensus is that the torque is not needed. I forgot that I had hand tightened them last time and it still took a full night soak in pb blaster to loosen it.
 

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After spending a couple hours on it (tried heating, breaker bar, etc.) and an appreciable amount of money on tools, making several trips to the auto parts store, I decided it'd be best to sever my losses and take mine in to a local motorcycle dealer and service shop

I basically told them, "I'm trying to change out my rear sprocket, I have the hub out, but am having a hard time with these bolts. There are six of them. Is this something you can do?"

It took the shop about 45 minutes to get the bolts off as well, but in the end, they only charged me $50.00 to remove these monsters and install the new sprocket (same-day).

Totally worth it in my opinion.
 
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