BMW Luxury Touring Community banner

1 - 17 of 17 Posts

·
Registered
Joined
·
71 Posts
Discussion Starter #1
The exhaust pipe is blowing.
Seems like a crack under the left foot-peg - just aft of the 4 into 1 join.

I know that to repair this will involve removing the eight nuts on the four pipes at the manifold and at least two of the studs will shear.
Then the head has to come off to drill out and replace the sheared studs.
Then find a welder to fix the pipe (the easiest bit of the whole process)

Do I ;
1. Settle back and start a long involved job.
2. Pretend it isn't important and keep washing the soot stains off by the left foot-peg.
3. Tear down everything while I am at it and re-furb everything I can find.
4. Leave it to the dealer and write a large cheque.

What would you do ?
 

·
Registered
Joined
·
4,342 Posts
The bolts should back out of the head before they shear so you should be fine there. The exhaust is I believe stainless so you will need to find someone who can weld that with the proper shielding gas or flux combination but it is not all that uncommon to have a crack there.

8 nuts and the o2 sensor once you get the tupperware off to see it all.
 

·
Registered
Joined
·
181 Posts
I had a rusted muffler, and crappy looking headers on my RT.
Had them ceramic coated, and like the looks. Removing the
exhaust should be without incidents, a welder knows how to
deal with stainless, and ceramic coating is not so expensive.
In the end you have a exhaust that is calibrated for your bike,
fixed and looking better (if you like black exhaust as most bikes
these days have) Good luck with your choice!
Just my 2 cents...
 

·
Wrencher Extraordinaire
2005 K1200LT
Joined
·
14,171 Posts
I have removed at least 8 exhausts on LTs and never had a stud shear off. You will need the copper donut gaskets and I recommend the new nuts they sell now. I would not waist money on a ceramic coating since you cannot see the pipes anyway. Check for flange cracks as well.
 

·
Registered
Joined
·
71 Posts
Discussion Starter #5
I have removed at least 8 exhausts on LTs and never had a stud shear off. You will need the copper donut gaskets and I recommend the new nuts they sell now. I would not waist money on a ceramic coating since you cannot see the pipes anyway. Check for flange cracks as well.
Any special tips for undoing the nuts ?
 

·
Wrencher Extraordinaire
2005 K1200LT
Joined
·
14,171 Posts
I have never done any prep work at all but look at them for serious rust (big growths). I have had nuts stuck on the studs and the studs have always just come out of the head. I would remove the nuts in a vise or double nutting and reinstall the studs. The old nut appears to be steel and the new nuts appear to be bronze. More common for exhaust nuts.
 

·
Registered
Joined
·
2,730 Posts
Just spray them with some penetrating oil, let it soak for an hour. (please something other than wd40) If the nut is frozen, the stud will come out. Buy new studs and nuts, they are actually cheap from the dealer, also the donut copper metalic crush seals. Torque is a tad over 16 ft/lbs.
Looking good with ceramic spray coating is nice but it also helps with corrosion if you are not using stainless steel pipes. There was a company that even treated the interiors. Think positive and this will be a piece of cake. :grin:
https://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias=aps&field-keywords=penetrating+oil+spray
 
  • Like
Reactions: Voyager

·
Premium Member
Joined
·
2,946 Posts
Use this formula with high success rate!

Home made Penetrating Oil


Here is an interesting finding on Penetrating Oils
Recently “Machinist Workshop Magazine” did a test on penetrating oils. Using nuts and
bolts that they ‘scientifically rusted’ to a uniform degree by soaking in salt water, they then
tested the break-out torque required to loosen the nuts. They treated the nuts with a variety
of penetrants and measured the torque required to loosen them.
This is what they came up with:
Nothing: 516 lbs
WD-40: 238 lbs;
PB Blaster: 214 lbs;
Liquid Wrench: 127 lbs,
Kano Kroil: 106 lbs
(ATF)/Acetone mix (50/50): 50 lbs.

This last “shop brew” of 50% automatic transmission fluid and 50% acetone appears to beat
out the commercially prepared products costing far more.
 
  • Like
Reactions: beech

·
Registered
Joined
·
71 Posts
Discussion Starter #9
And so we learn.

Six of the studs had the nuts well rusted on - and the studs just came out smoothly. Seventh stud; the nut came off and then the stud was removed easily with two nuts locked. Eight new studs and nuts are arriving tomorrow.
Stud number eight had sheared many years ago. Before I bought the bike. I might be able to get the stump out but it is getting to the stage where I might be making more of a mess getting it out than leaving it in. The first drill hole was off centre. I have managed many miles without it - so maybe it can stay as a sheared stump.

Clymer was not as helpful as I had hoped but the routine of "Read Manual, Observe set-up, Think, Act", (in that order) worked well and the exhaust was easily removed, albeit slowly.

Now I have a one piece exhaust (score marks were made before removal for the welder to align in case it separated) with some mighty cracks - but they are in the "easy to weld area" downstream of the box, not in the "four into one" part.

Since a new exhaust (less oxygen sensor) will run to about USD1800 I can afford to pay "local skilled welder" a stout fee for his trouble.
(New studs, nuts and gaskets run to about USD45, I know an excellent BMW dealer with a brilliant guy on the parts desk who will take a phone order and post the bits next day. They are superb and I use them all the time for my bikes.)

This could be a successful project.

Question. When the new studs go in, Should I use any Copper grease or Locktite or just plain in ?
 

Attachments

·
Registered
Joined
·
4,342 Posts
And so we learn.

Six of the studs had the nuts well rusted on - and the studs just came out smoothly. Seventh stud; the nut came off and then the stud was removed easily with two nuts locked. Eight new studs and nuts are arriving tomorrow.
Stud number eight had sheared many years ago. Before I bought the bike. I might be able to get the stump out but it is getting to the stage where I might be making more of a mess getting it out than leaving it in. The first drill hole was off centre. I have managed many miles without it - so maybe it can stay as a sheared stump.

Clymer was not as helpful as I had hoped but the routine of "Read Manual, Observe set-up, Think, Act", (in that order) worked well and the exhaust was easily removed, albeit slowly.

Now I have a one piece exhaust (score marks were made before removal for the welder to align in case it separated) with some mighty cracks - but they are in the "easy to weld area" downstream of the box, not in the "four into one" part.

Since a new exhaust (less oxygen sensor) will run to about USD1800 I can afford to pay "local skilled welder" a stout fee for his trouble.
(New studs, nuts and gaskets run to about USD45, I know an excellent BMW dealer with a brilliant guy on the parts desk who will take a phone order and post the bits next day. They are superb and I use them all the time for my bikes.)

This could be a successful project.

Question. When the new studs go in, Should I use any Copper grease or Locktite or just plain in ?
Make sure and snap a pic of the repaired exhaust so we can see the skill required/executed to fix such an issue.

As far as the new studs go, without making any effort to find the proper way of doing it, I would probably put them in dry and snug them down. If the new nuts are brass as John alludes to then there should not be any further issue of getting them loose. Be aware the clymer torque in my book is incorrect so maje sure you do not strip or snap any of the new studs/nuts if you are working in Ft/Lbs and not Nm.
 

Attachments

·
Registered
Joined
·
2,730 Posts
Do some research on stud removal. Left hand drills are your friend. Half the time they twist out a stud. Otherwise, flatten the nub face with a die grinder, center punch and either left hand twist drill or a small carbide spade drill. Or find a machine shop that will work on it for you while being a whole motorcycle. Your going through a lot of work and another $75 invested in getting that bugger out is well spent. Your headed down the path to a fun summer of riding.
 

·
Premium Member
Joined
·
7,615 Posts
Use this formula with high success rate!

Home made Penetrating Oil


Here is an interesting finding on Penetrating Oils
Recently “Machinist Workshop Magazine” did a test on penetrating oils. Using nuts and
bolts that they ‘scientifically rusted’ to a uniform degree by soaking in salt water, they then
tested the break-out torque required to loosen the nuts. They treated the nuts with a variety
of penetrants and measured the torque required to loosen them.
This is what they came up with:
Nothing: 516 lbs
WD-40: 238 lbs;
PB Blaster: 214 lbs;
Liquid Wrench: 127 lbs,
Kano Kroil: 106 lbs
(ATF)/Acetone mix (50/50): 50 lbs.

This last “shop brew” of 50% automatic transmission fluid and 50% acetone appears to beat
out the commercially prepared products costing far more.
Here is a similar test that got very different results. Not sure what to make of it.

 
  • Like
Reactions: RockyRoad

·
Registered
Joined
·
71 Posts
Discussion Starter #13 (Edited)
Ideally the head would have 9 studs. 8 to hold the exhaust on and one to shear off when you looked at it.

The sheared stud (which broke years ago, before I bought the bike)was eventually drilled out and 8 new ones went in. Usual problem, it was too tight for the extractor (fear of snapping it off) so I had to drill a larger hole - but we were now off centre. Drills were going sideways into the softer metal of the head so a dremmel tool was used to work at the remaining steel crescent without cutting into the aluminum. Then the hole re-threaded.

The pipe came back from the welder and it is fitted, but not yet torqued down. Gear linkage is having a bit of a clean and grease.
Only worry is if the welding fumes knackered the oxygen sensor. Not sure if this is a valid concern but we will see. Should be riding "The Luftmeister" on Tuesday.
 

Attachments

·
Premium Member
Joined
·
7,615 Posts
Ideally the head would have 9 studs. 8 to hold the exhaust on and one to shear off when you looked at it.

The sheared stud (which broke years ago, before I bought the bike)was eventually drilled out and 8 new ones went in. Usual problem, it was too tight for the extractor (fear of snapping it off) so I had to drill a larger hole - but we were now off centre. Drills were going sideways into the softer metal of the head so a dremmel tool was used to work at the remaining steel crescent without cutting into the aluminum. Then the hole re-threaded.

The pipe came back from the welder and it is fitted, but not yet torqued down. Gear linkage is having a bit of a clean and grease.
Only worry is if the welding fumes knackered the oxygen sensor. Not sure if this is a valid concern but we will see. Should be riding "The Luftmeister" on Tuesday.
Nice looking welds. Just torque carefully and be sure you have the right value. At least one Clymer edition had an incorrect value.
 

·
Registered
Joined
·
1,534 Posts
Well. Nice Job. I was gonna suggest replacement as an option. But i see you are well ahead now.
 

·
Registered
Joined
·
1,534 Posts
We use Kroil at were i work. It usually works on really nasty bolt/nuts. Usually. The only times i seen it not work is when the nut or bolt flats are rusted away and beyond tools being able to grab. But sometimes a bolt extractor will remove those. Kroil or blaster I've found will 8 times out of 10 work. But some are destined for the hot wrench.
 

·
Registered
Joined
·
71 Posts
Discussion Starter #17
Job done. And a lovely test ride on a glorious day with a strangely quiet bike.

Top Tip - When removing fasteners, push them through a piece of cardboard in a pattern that matches where they came from.
A month later, when you have no memory of what went where it tells you all you need to know.
Amazingly I had no left over screws and no holes without screws.

Tupperware geeks will recognise the patten of upper and lower port side fairing fasteners. Which for some reason is upside down in this post. (Note the pack of Spieglers - another story to follow ).

The cardboard was from a box of very good beers from Marstons's
 

Attachments

1 - 17 of 17 Posts
Top