[jdrouin]

Hello All,

I also stripped the gearbox bolt today on my 2007 Bullet Classic. I thought I was gingerly tightening it little by little but all of a sudden what small resistance had been there gave way and, well...

Just wondering if anyone has tried the spark plug thread fix covered in the Snidal manual, or has any other advice.

Not a good day for motorcycle maintenance...

Jeff

[c1skout]

Helicoil? Tap for next larger size?

[Rick Sperko]

I just did a helicoil on my distributor. It went well. If possible practice on a piece of scrap. If you search for stripped distributor you will probably find my write up on it.

Good luck,
-Rick

[1Blackwolf1]

  Most hardware stores or auto stores have metric heli-coil repair kits in a variety of sizes.  If you follow the instructions provided you won't have any problems doing the repair.  The biggest thing to remember is go slow and use lots of lubricant when tapping the hole out to the next larger size, since you are working with aluminum the tap can bottom out and you could crack the casting if you go to deep.

  The best caution is to use a small drill and mark how deep the hole is currently with a piece of electrical tape and remove the tap frequently during the repair, blow out all the small chips you are going to create.  Once the hole is deep enough the heli-coil should be coated with some type of permanent thread locker solution, loc-tite blue is good if you have it already if not get the red it's stronger and more permanent.  Use the included setting tool ands install till just snug.  Don't put a lot of torque on it or it could strip out also. 

  It sounds harder than it is really...slow and steady wins the race here...at least you did it on a less critical bolt than the sparkplug.  It's best to remove the head to fix a plug.  This is a good learning opportunity,  you can do it.  Will.

[stipa]

Which bolt did you strip?  Was it on the side cover?

[jdrouin]

Yes, sorry I forgot to specify. It's the large bolt in the fill hole on the side of the gearbox.

I'll see if my local hardware store has the helicoil thing. Thanks for your advice.

Jeff

[1Blackwolf1]

  The only thing to add then is you should make every attempt to keep the chips or flakes out of the gear box so they don't end up in the gears.  They should fall to the bottom of the gear case if you don't catch them, so a change of gear lube at the end is probably called for.  Good luck, Will.

[geoffbaker]

Tapping is a simple but slow process. Remember to add oil, then turn the tap 1/4 turn, stop, and then turn back; this frees the chips and stops them from cutting into the new threads you are cutting. Repeat till done.
You might consider draining the oil, taking off the side covers, then tapping. That would be the safest procedure Remove the tap regularly and blow out the chips. When you are done you can wipe out any loose chips, then reassemble and reinstall the covers and gasket and add gear oil back in.
You could of course try to find the next size larger bolt instead of using a helicoil with the existing bolt.

You can stuff a rag into tthe gearbox around the hole to keep the chips contained as you work.

Lastly, if this is something you don't have time for right away, keep in mind that this bolt is under no strain, and you could easily loctite it or silicone it into place until you have time to make the repair.

[Vince]

    Helicoils work well in the smaller sizes (6-8mm or1/4-3/8),  particularly for infrequent use bolts. Larger bolts are better repaired using a solid insert (Time Sert tm) . Grease the cutting tool, Back it out and clean the grease and the filings the grease is holding about every one to two turns. This will minimize the metal chunks that fall inside. You will still need to change your oil after. Be sure to match the length of the coil or insert with the depth of the hole.
     Given the cost of a GOOD kit to do this, plus the learning curve to use it (yes you should practice on some scrap before attempting this on your bike), I would advise letting a shop do it. It might be cheaper in the long run.

[jdrouin]

OK, so I've looked up both the Heli-Coil and Time Sert products. Both products are similar, and the process seems pretty straightforward (though I also said that about adjusting the drive chain tension).

These videos explain the process pretty well.

Helli-Coil: http://www.youtube.com/watch?v=RFYa6sjhh_E

Time Sert: http://www.youtube.com/watch?v=uP2Up_hG7rc

My concern with either of these would be in setting the insert too far past the cover so that it interferes with the gears. Also getting the right diameter and pitch measurements of the plug, since I don't have any such tools.

Before I do anything, I think I'll ride a few blocks (after I get the drive chain adjusted and the wheel aligned) to see if gear oil comes out of the stripped plug. If not, maybe I can get by without re-tapping the fill hole until my aluminum skills improve with other maintenance procedures, and then give it a shot.

Thanks to everyone who responded. I'll let you know how it turns out.

Jeff

[1Blackwolf1]

  Geoff had an excellent idea, you could always thread it back in until snug and use clear RTV aound the outside.  A decent machine shop probably wouldn't charge much for the repair if you had the cover in hand and all they had to do is insert the repair coil. And they would be able to match the pitch and thread quickly.  But I doubt you would loose much oil.  Will.

[t120rbullet]

You might want to check the price of a new cover.
Might be less than a heli-coil kit or having someone fix it for you.

[jdrouin]

When I pulled the plug again today I noticed a ton of aluminum filings on the ground where some gear oil had collected, as well as on the plug, in the threads of the cover, and floating on the oil inside. So I drained the gear oil, cleaned everything out as best I could, and refilled it with new oil.

When I put the plug back on I used blue loctite. By that time it was too dark to ride and see if it will hold the oil, so I'll check in the morning. It seems like it will probably be alright, at least temporarily.

The gearbox cover does not seem to be sold separately on our host's website, so if this doesn't work I'll just call to find out.

Thanks again.

Jeff

[birdmove]

    You may find the price of a Heli-Coil kit that big is as much,or more than a new cover.

    jon

[jdrouin]

OK, so I rode for about 7 miles on local city streets, including a 45 MPH uninterrupted run on a 2 mile service road. Also did some spirited acceleration and turning in some of my favorite twisty areas. No leaks whatsoever from the gearbox. The blue loctited bolt is oil tight.

I'm just wondering if it will hold up when I drive it about 200 miles to Boston at the end of the month for Winter storage. Guess I'll try a parkway run later this week to see how it does with that, and will probably order a new gearbox cover along with some other goodies for when I take it out of hibernation in the Spring.

Thanks all for your help.

Jeff