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Gearbox Ground Thread Stripped

This thread insert idea has been rehashed a bunch here & there but I don't know the location of that screw w/o looking as for amt of metal and opening to work but I'll throw this out- there are many brands of inserts & many have different "models" that offer various metals,lengths and wall thicknesses and that's in addition to the fact that there various installation methods & tools needed. Some also offer threads not available in others. Some you have to buy several , others only a few. My point here(comes from experience) is to not limit your search to helicoil brand. Once you know every aspect of the situation then look for what works best for that.
I often use a brand/model called "Thinsert" and there are suppliers that will sell a couple. They are thinwall but strong. It's possible to install some types/brands w/o buying special tools needed for insertion or special taps that are weird sizes & pricey. Look around a lot before you pick one. The Chinese are selling insert kits on ebay too. Fastenal is all USA over but charges a bunch for shipping small stuff that comes in on their own truck! & it comes to them, not my house. Ebay is a good place to wander around the insert types .
 
Is "Thinsert" the same as a Timesert? When I google thinserts in get dental inserts. ???

I've seen timeserts used twice now and have been impressed. I think they work best when there's lots of meat to drill into though and not sure how thick the rear transmission cover is. This would be a factor of course. Whole bunch of good videos on how they work here: http://www.timesert.com/html/install.html#A

They are not as cheap as helicoils; about $63 on ebay for the tools and five 6mm inserts. http://www.ebay.com/itm/TIME-SERT-N..._Automotive_Tools&vxp=mtr&hash=item43b1244897 Amazon sells these also at similar prices.

I like the idea of replacing aluminum threads with solid steel ones in places where the aluminum threads have failed anyway.
 
Alter ground

I didn't like to undo that bolt and remove the ground strap every time I went in to the front cover.So,I cut a slot in the lug at the battery and I loosen the bolt at the battery and slip off the cable leaving the trans bolt alone.
 
Google "Keensert thread insert" The insert I've used last several times is the one that has a slot similar to a gland nut on top and if the treads are loos you can screw it in with a fat tip screwdriver or if room you simply place a cap screw with a stopper nut and wrench it in. They come with a dollop of red Locktite on them. It's always a matter of each situation and which insert fits that scenario. Most machine shops already own the taps,etc., for helicoils but to avoid that expense I like inserts that use "normal tap sizes" , which I already own. Fastenal sells several choices but you have to pay them to deliver it to their store on their truck which is a rip to me as they are coming anyway! I think I had to buy 5 where I got mine last time. Look on ebay at the metric insert kits -maybe those will work?
 
At the moment I am still evaluating various options for thread repair. I am appreciative of the input from the community, as well. My single trepidation is that I would rather not pull the gearbox as it requires a great deal of other dis-sembly. The clearance is minimal between the front of the swingarm and the rear of the gearbox where the screw resides.

Some thread inserts that are intended for use in wood attracted me though I am all too aware that a correct repair will give me the best long term result. The ultimate removal of the gearbox seems inevitable, but i's 25 degrees today, so i am not in a hurry.
 
Pulling the transmission

There isn't all that much to pulling the transmission back. If you pull the swingarm pivot pins, and drop the brake pedal assembly, you can pull the swingarm back far enough to easily remove the tranny. I use a tie down strap to hold the wheel/swingarm assembly back , wrapped around the rear fender.
 
OK, all done.

First I disconnected the ground (HA)! I removed the swingarm pivots to allow me ability to remove the shock.
Second, I rigged a NEW 1/4" bit into a flexible shaft. This was needed for the additional required to reach the hole. The bit went in under the frame gussett at the swingarm pivot.

Straight shot! Took all of 10 seconds to run a bit into the hole. I had shoved a rolled up towel into the speedo drive to prevent swage from entering. I then used my aluminum magnet to remove the shavings. The aluminum magnet consists of a tiny screwdriver with a bit of oil on it. Clean as a whistle.

Then ran a M6 X 1.0 die over the bolt to make sure it was clean.

Then I inserted the OEM Brand thread insert (AutoZone) into the hole. Then I put the whole deal back together. Total time, exclusive of shopping <1HR.
Don't ask me how much I spent!!!!!

Thanks.

Rick
 
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