Cracking the case on an XJ650 - middle gear TORX bolts

I got a problem!

I like my XJ650 Seca. I like it a lot! It has a problem with first gear that I want to fix. Unfortunately, the only way to do that is to crack the case.

So, I've got the engine mostly disassembled, and about the only step left before I do so is to remove the "middle gear" assembly, as it involves a metal plate that bolts in to both halves of the case.

The official yamaha shop manual just says "remove the TORX bolts that hold in the middle gear assembly" Easy enough, right?

So I go about it and it's not long before I'm stripping out the TORX heads. Huh? What the heck? Upon closer inspection I notice that the bolts themselves are punched in to holes on the plate behind it. As in, the edge of the bolt is struck with a punch so it indents into a notch on the plate, preventing the bolt from spinning out.

This is great, except it also prevents you from EVER REMOVING THE BOLT.

Has anyone else ever dealt with bolts like this? I have no idea how I'm going to get those out. Maybe I could drill out the indented part? There's not enough room to get a dremel in there to do any cutting, and also not enough room to get anything under the punched part to try and bend it back out.

aaauugh!

 

Drilling the indent will help, you don't neet to drill all the way through just enough to get the indent off. Your biggest helper is a impact screwdriver, if you don't have one get one. They are available most anywhere for under 20$, I have a real cheap one from Harbour Freight and it works well. If you have alreaded rounded off the bolt then its time to drill the head off and extract the leftovers.

 

Impact driver plus extension plus 1/2" to 3/8" adapter plus torx bit.

The above works a charm, although I didn't read the drilling the indent out part until after I'd gotten them out... which goes to show an impact driver, leather work gloves, motor lying on its side and a big hammer will get you far.

 

The maintenance manual states that you need to drill out the staking before you try to remove the TORX. As Mlew pointed out, you don't need to drill far. Easy day after that and a little help from our friend, the impact tool.