Loctite the exhaust nuts?

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maylar

maylar

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I've been through dozens of posts regarding tightening exhaust nuts on a Commando, and none of them ever suggest using some sort of liquid thread locker. Is there some obvious reason why that is not an opton?
 
maylar said:
I've been through dozens of posts regarding tightening exhaust nuts on a Commando, and none of them ever suggest using some sort of liquid thread locker. Is there some obvious reason why that is not an opton?
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Heat?
 
The heat is too much for most thread locking stuff I've used but its also not really necessary. Just retighten them when the engines good and hot and as hard as you can.
I don't use any lock wire or the lock rings.
 
Afew years back I tried applying "Red Loctite'" to my exhaust clamp nuts. It worked OK, until the next I had to take them off, thats when the stuff started wadding/galling up on the threads. I was feaking out for a few minutes as it felt like I might be ripping out the threads as I turned the nut, I managed to get them off without damage, but, I wouldn't use the loctite again. Probably the best method would be to some how attach a spring that would hold constant tension in the tightening direction. I have considered creating and manufacturing some sort of hook and spring device that would slip around the nut on each side then be connected together with a spring, unfortunately it would be very difficult to do so because of the variety of exhaust nuts in use. I have also heard that the bronze exhaust nuts work well and stay tight.
GB
 
geo46er said:
Afew years back I tried applying "Red Loctite'" to my exhaust clamp nuts. It worked OK, until the next I had to take them off, thats when the stuff started wadding/galling up on the threads. I was feaking out for a few minutes as it felt like I might be ripping out the threads as I turned the nut, I managed to get them off without damage, but, I wouldn't use the loctite again. Probably the best method would be to some how attach a spring that would hold constant tension in the tightening direction. I have considered creating and manufacturing some sort of hook and spring device that would slip around the nut on each side then be connected together with a spring, unfortunately it would be very difficult to do so because of the variety of exhaust nuts in use. I have also heard that the bronze exhaust nuts work well and stay tight.
GB
Click to expand...

Uh, a spring? That's why they invented safety wire...
 
I thought u were supposed to do it cold because the vibes will strip out the threads???
 
No, you're supposed to keep them tight because if they get loose, then the vibes will chatter them about enough to screw up your threads. Torquing while hot and running is the accepted way of preventing this. I did a few times, to 60 lbs-ft and occasionally check but after the first couple retightenings this way they've stayed tight and the wrench always clicks without moving them further since.
 
I've always used bronze nuts as they have the same expasion rate as alloy and never come slack when tightened up correctly.

Cash
 
here is how i keep my nuts tight and it works
Step 1 use the 850 type nuts with the larger fin on the nut
Step 2 drill and tap a hole through this large fin
step 3 fit grub screw into newly drilled and threaded hole
Step 4 tighten nuts when hot and then tighten grb screw
Step 5 have a beer and concretulate yourself you will never have loose nuts again
the reason this works is the grub screw is clamping against the header pipe and stops the nut trying to unscrew
also if you use a small grub screw you would never know it was there and great if you have a show bike
 
I haven't had a problem after doing the nuts up with the motor hot. However, warm the engine up before removing them or you may do some thread damage.
 
Antiseize in an application like that is always a good idea. The Nortons aren't quite as tempermental in this regard as old BMW airheads (I religiously remove and reapply antiseize to my airhead's exhaust header threads annually, and not because I think it's fun) but it's still advisable.
 
Safety wire works well and I think it looks cool:

Loctite the exhaust nuts?
 
I have always used copperslip on the threads, done them up tight from cold, then re-tighten when stinking hot. I suppose the lubricant makes sure that they are really clamping onto the sealing ring.

They have never come loose. I speak from 33 years experience of commando ownership.

The lock wires, by the way, dont look cool, they look like like a right old bodge up, which, i suppose, is just what they are!

Lock rings have a tendancy to rattle, causing owners to worry about some major engine malfunction, before realising the real cause.

As with most things commando related, there is a simple way & many more complicated ways to resolve each little hic-up. More often than not the simple way is perfectly adequate, easier to achieve & cheaper.

Bob.
 
@ Bobolink: where do you attach the lock wires ? could you please post a photo ?
 
One of my exhaust ports has a slightly buggered thread and the nut is hard to turn. That one never comes loose, but the other side is forever vibrating out. I had the 850 rattle rings when the bike was new and they probably contributed to having to get the head repaired with welded inserts, which I did in the early 80's.

Safety wire and springs are just fugly, IMO.

I didn't intend to create another "How do you keep the exhaust nuts tight" thread, the subject has been discussed here many times. It just seems like with all the modern chemistry available somebody would be selling a high temp thread lock compound that isn't also permanent. I guess not.

So, I will continue to use steel Suzuki crush washers (as recommended in an old Norton Tech Digest), put the Fear Of God into tightening the nuts, and be forever doomed to carry that big hook spanner with me when I ride.

<sigh>
 
Ever since the time I fried my boot holding a pipe on until I got stopped I've safety wired them. It seems redundent not that I have the big tool and tighten them hot, but it makes me feel better. Since the way you remove Loctite is heat I reckon that would not do a lot of good here.
 
Bodge up? Whatever, thats your opinion.

Here is another opinion: use aircraft safety wire and your parts won't rattle off. Also there would be less posts about loose exhaust nuts
 
hi all,if you,re after a concours show winning bike stick to the original setup ,if you want a bike to ride regular and hard why not use lock wire,and not just on the exaust nuts,its not a bodge,racers dont bodge their bikes and if you look closely at a race bike you will notice lockwire in all the critical safety areas where a nut or bolt can undo and cause a serious accident,and this includes the exaust pipes
 
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