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Ran into a nasty issue with the cylinder head mounting stud

Yep!

I guess I have been very blessed during my 50 years of drilling and tapping hundreds of holes by hand only to have never messed one up. How did I ever get by without those fancy contraptions?

Right on pard.

Using the tap guide to get you started ain't a bad idea for a newbie, especially since the tap included in the kit is a plug rather than starting tap, but the experienced folks shouldn't have an issue.

As for drilling the old threaded hole, it's already there and square with what is needed. You're only reaming for diameter, and that's barely more than the old thread major diameter. Kinda hard to make the hole crooked unless it was already crooked before you started! We aren't filling and redrilling the case, just cleaning out the old thread pattern.
 
BMW stud tool

Just to let you know there is a company in Boulder Co that makes and sells a stud tool that works very well.
My brother owns one and has rented to other enthusiast on occasions.
You can see the tool here and his review on there page
Aaron D
http://www.hpd-online.com/stud-tool.php

Good luck with your repair
Dave
 
I have a ratcheting tap handle that is 12 inches long. With care, and a handle this long, any angular discrepancy is minimal. It is a lot easier to get crooked with a very short tap handle.
 
Ratcheting tap handle?

I have a ratcheting tap handle that is 12 inches long. With care, and a handle this long, any angular discrepancy is minimal. It is a lot easier to get crooked with a very short tap handle.
What is a ratcheting tap handle,never saw one?
Dave
 
And again, the manuals are wrong about 29 pounds on those studs. 25 is plenty. Also, unless you have just done a top end and need to follow the re-torque procedure, leave them alone - meaning, resist the urge to torque them everytime you adjust your valve lash.
 
Sorry for warming up this old post...

I have the same issues with my top right stud on the right cylinder. I am on the fence if I should tackle this myself or pay someone to do it.

There is one thing that hasn't been covered in this thread (I think). How do you get the small hole drilled in the insert that is needed for the oil supply? That seems like a big deal to me. Is there any documentation about this? Thanks!
 
I have the same issues with my top right stud on the right cylinder. I am on the fence if I should tackle this myself or pay someone to do it.

There is one thing that hasn't been covered in this thread (I think). How do you get the small hole drilled in the insert that is needed for the oil supply? That seems like a big deal to me. Is there any documentation about this? Thanks!

We had a recent thread on this subject. It's imperative that a drill guide be used so that the drilling is done perfectly straight...if not, then the small angles that it is off means that the studs will not be parallel when they get all the way out to the head and rocker arms. Things might not fit then. In my book, this is a critical job and I'd want someone who had done this before either looking over my shoulder or have a trained mechanic doing it.

The service bulletin mentions that the helicoil should be installed 2mm below the outside surface of the engine case. This should result in the oil feed path not being blocked. Snowbum discusses this and more near the bottom of this page:

http://bmwmotorcycletech.info/break-in.htm
 
All Eight

As the title of the reply says, stay clear of the Helicoil product for this repair.

The correct product to use is called a time sert:

http://www.timesert.com

It is the preferred replacement because it is not a wire coil, but a solid tube threaded to fit your application. Helicoils pull out in most of these uses and you will end up tearing down again and replacing it with a time sert anyway. Spend the couple extra bucks and buy the insert kit for your job. It'll never pull loose or separate and will be worth the dough in the long run.

Just did one myself on a stripped cylinder stud that some ham-fisted BMW dealer "technician" stripped at the 600 mile service on my R1200GSA...[/QUOTE

I ended up putting TimeCerts in all 8 of my cylinders’ studs. AVOID Helicoils.
 
Stud fixed with Heli-Coil

I just fixed a stud with a Heli-Coil. Turned out well and feels very strong. No issues after 300 mls of driving. I added some details on my website (below) under "Technical".

I rented a drill rig, I am glad I did. I am sure it can be done without if you are trained, but I didn't want to take that risk.
 
Tread repair

Reply to post #31
Are you saying that on a new bike durning a 600 mile service a stud was stripped out and you fixed it !
Why would you not demand a new bike from the dealer or a new head and a extended warranty, are you going to give full disclosure to a new buyer when you sell the bike? Did you except a insurance settlement and repurchase bike with a salvage title? I don't know all the details but it sounds f****d up
 
Heli-coil vs Time-Sert? It is much much more important with either system to maintain the original thread axis alignment. In my experience w industrial fatigue applications an original thread is not as strong as a Heli-coiled thread, but if the the alignment is off just a little bit, there will be a progressive thread strip out and neither system can be strong.
 
One downside of a Time-Sert is that you have to drill a bigger hole than with a Helicoil. Sometimes there is not enough metal.
 
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