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Secondary butterfly removal:how screwed am I?

Joined
Mar 18, 2013
Messages
161
Location
CA
A while ago I bought the dobec TFI from holeshot, along with everything needed for stage1 or 2 build. I did stage 1, and did not proceed with TB butterfly removal because I could not get a single screw to break loose. I busted my p00 bit, I tried heating with a propane torch, they wouldn't budge. So I just used stage 1 settings.

Now I was working on the bike, installing header, flushing coolant, etc. Got bitten by the "while I am at it" bug, and decided to get the secondaries out. I got 2 new heavy duty p00 bits, impact screw driver. Zip. Just stripped the screws. Not a single one would budge.

I said "Screw it, I am drilling them out". So I did. I went through 3 drill bits (2 of them craftsman), and got all of them out... except the #1 unit. I broke 2 bits on that, and on 2nd bit, it got wedged at an angle as it snapped in half.

While extracting and cleaning, looks like I tore through the bar. As you can see in the pics:

#1 TB closed position
A7XS060.jpg


#1 TB open position
BZdV5aI.jpg


Another TB for comparison, which is how all 3 others turned out (ie. just fine).
YYGMOgrl.jpg


So, this being the case, what's the worst that could happen? I am guessing one of the following:

1. Eventually with time, as the motor turns it on/off, it will snap the upper torn beam (as it's closest to the motor) and leave a twisted portion moving?

2. Both halves snap in time since the bottom half will not take twice as much force to twist?

3. Nothing, and it'll be fine since it no longer has to rotate the mass of plates, screws, etc?

What should I do at this point? I remember someone made a post on here about removing the beam and motor, but I am having issues finding that post at this moment
 
Joined
May 8, 2011
Messages
881
Location
NW GA
Agreed. I don't have pics of my "fun" with the secondaries but recall doing something similar maybe not quiet as bad and its been about 22k miles and the bike continues to run! ;)
 
Joined
Nov 7, 2007
Messages
2,071
Location
Antelope Valley CA
First Name
Scott
Last Name
Brown
Agreed. I don't have pics of my "fun" with the secondaries but recall doing something similar maybe not quiet as bad and its been about 22k miles and the bike continues to run! ;)
I still have a hard time understanding how so many people seem to have great problems removing those 8 little screws, as it seems to run from very easy removal of the screws to extremely diffiicult, and when I removed mine I simply heated up the screws a little and they all came right out.

So given the fact that they are all installed the same at the factory I cannot for the life of me understand why this happens, and if it is a function of the screws or the screw remover or both.
 
Joined
Mar 18, 2013
Messages
161
Location
CA
You are under the assumption that every part is mechanically and systematically assembled, with precise equal torque, and no possibility of issues or failures. If this was the case, people wouldn't have warranty issues right out of the box, etc.

As I have stated, along with many others, that even with heat and precise bits, it was still impossible to remove any screws. On my bike, they were so tight that every single one of them stripped. I tried an impact screw driver, a socket and wrench, and plain old screw driver with lots of down force, and all of them came out exactly the same: stripped heads.

Maybe you machine your own extremely precise fitting tools for this job :)
 
Joined
Mar 18, 2013
Messages
161
Location
CA
Tidy up any loose metal and use it as is. Very little pressure on the shaft
Hm.. I am still a bit worried about doing it mainly because one side of the hole is completely obliterated. I have absolutely 0 desire to revisit the manifold in the future.

I could consider sticking the mig tip in there, but I'm not even sure I could get a good ground with these conditions
 
Joined
Mar 18, 2013
Messages
161
Location
CA
kewwig, you're right. I looked at it today in depth and it just rotates the STP sensor. My worry is that with time it will eventually start giving way. I'd think about just putting a dab of steel epoxy there to tie the two rods together at that spot, but my concern there is if it happens to come off, it'll go straight into the combustion chamber. Highly unlikely, but I still worry.
 
Joined
Jul 26, 2009
Messages
236
Location
New Zealand
I still have a hard time understanding how so many people seem to have great problems removing those 8 little screws, as it seems to run from very easy removal of the screws to extremely diffiicult, and when I removed mine I simply heated up the screws a little and they all came right out.

So given the fact that they are all installed the same at the factory I cannot for the life of me understand why this happens, and if it is a function of the screws or the screw remover or both.
I have done 4 sets now. One was just impossible and the screws did not want to budge no matte what, so they got drilled after the heads on a couple did an impression of cheese. The other 3 sets were fine with a butane pencil torch and came out quite easily.
 
Joined
Jul 26, 2009
Messages
236
Location
New Zealand
kewwig, you're right. I looked at it today in depth and it just rotates the STP sensor. My worry is that with time it will eventually start giving way. I'd think about just putting a dab of steel epoxy there to tie the two rods together at that spot, but my concern there is if it happens to come off, it'll go straight into the combustion chamber. Highly unlikely, but I still worry.
I wouldn't use epoxy on that. At some stage it will come free. The secondaries don't torque the shaft like the primaries do and it's highly unlikely it will let go. If it really worries you, get another set of TBs. They come up regularly quite cheaply, although some people want silly prices.
 
Joined
Nov 7, 2007
Messages
2,071
Location
Antelope Valley CA
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Scott
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Brown
You are under the assumption that every part is mechanically and systematically assembled, with precise equal torque, and no possibility of issues or failures. If this was the case, people wouldn't have warranty issues right out of the box, etc.

As I have stated, along with many others, that even with heat and precise bits, it was still impossible to remove any screws. On my bike, they were so tight that every single one of them stripped. I tried an impact screw driver, a socket and wrench, and plain old screw driver with lots of down force, and all of them came out exactly the same: stripped heads.

Maybe you machine your own extremely precise fitting tools for this job :)
I was not implying that you do not know what your doing and my remarks were not meant as criticism towards your mechanical abilities in any way, but like a stated, just what causes some screws come out easily and others not to. ;-)
 
Joined
May 8, 2011
Messages
881
Location
NW GA
I even got the fancy screw driver broke on the 1st bolt in 30 seconds. Ironically it was labeled "Made in USA" go figure lol. Anyways I had to buy fancy titanium drill bits as the ones I had didn't do much then again I think they were worn to begin with! ;)
 
Joined
Jan 2, 2006
Messages
3,851
Location
Kempner, TX
First Name
Erik
Not that it helps now.. but for others....
The issue I find most often when this comes up is.. the fastener was not heated enough.. it can be very deceiving as you try and heat it up as the part is such a good heat sink.

I have shown this time and time again to folks that swear they are heating enough,, I have um try, then SHOW them with a IR temp gun or touch type thermocouple how far off the needed mark they are to soften anaerobic thread lock.

The entire part surrounding the fastener as well as the screw itself needs to be 250c or better for a few seconds , till the thread lock will soften.

Thats hard to do with a torch in such a small place and not under or over do it damaging things.

A steel rod heated to cheery red and touched to the fastener 60 sec, then reheated to cherry, touched again for 60 sec, and a well fitted driver bit that is heated a little so as to not draw too much heat away from the fastener will work every time....so long as the back of the screws are not peened over.
 
Joined
Mar 3, 2011
Messages
559
Location
australia
I used an 80 watt soldering iron ,a pissy 25w will never get enough heat .
I too was surprised how easy they came out. Screwdriver in and crack it
open .,not a little pressure and then a little more .
Telling the screws before hand that your boss and to do as they are told helps also .
 
Joined
Nov 7, 2007
Messages
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Antelope Valley CA
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Scott
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Brown
Yup, an 80 to 100 watt soldering gun held against the head of the screws for at least 30 seconds to 60 seconds, and I'm starting to also think that the main cause of hard extraction of the screws is simply people not applying enough heat to them, and I used an 80 watt Weller soldering gun to heat up my screws.
 
Joined
Mar 18, 2013
Messages
161
Location
CA
Well, too late for me to try this now :) However, I did have a propane torch on the screw for a while. I'd be surprised if it was under 100c temp.
 
Joined
Jan 2, 2006
Messages
3,851
Location
Kempner, TX
First Name
Erik
Well, too late for me to try this now :) However, I did have a propane torch on the screw for a while. I'd be surprised if it was under 100c temp.
But was it OVER 250C long enough to soften ,, which is the low end for release of most anaerobic thread lock compounds :giveup:
 
Joined
Nov 7, 2007
Messages
2,071
Location
Antelope Valley CA
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Scott
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Brown
Well, too late for me to try this now :) However, I did have a propane torch on the screw for a while. I'd be surprised if it was under 100c temp.
What your trying to do is loosen the thread locker on the screws by heating up the heads of the screws, and I feel that a small propane torch might be to much heat if over applied, as the screws and the butterfly body shaft are both made out of steel, and if you heat up the butterfly shaft to much its just going to expand and possibly apply even more pressure around the body of the screw making it even harder to remove.

Thats why I think that a hot 80 to 100 watt soldering iron applied to just the head of the screws for 30 to 60 seconds to soften up the thread locker is all thats needed to make the screws easy to remove.
 
Joined
Mar 18, 2013
Messages
161
Location
CA
Anyway, moot point. It's drilled out already :) Next bandit I get, I will get a pencil torch or 100 watt soldering iron to put heat on the butterfly screws :)
 
Joined
Mar 18, 2013
Messages
161
Location
CA
impact screwdriver is the one you tap with a hammer and it performs a small rotation, so force is centralized. Not an impact gun driver with an air compressor :)
 
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