Exhaust nut woes

On the thread I started yesterday about a front iso issue I commented on having to remove the RH exhaust system (for the first time) to remove the iso through-bolt. What I found was:
1. I was amazed at how poorly finished to exhaust port threads are on a FullAuto head. You would slice your finger on the serrated thread tips.
I brushed them with a SS brush to clean of soot. This almost entirely smoothed the thread crowns. I think I will still follow @ludwig s advice on using copper paste.
2. The sealing washer was a machined piece - flat one side with a pronounced dome the other - very like this RGM item https://www.rgmnorton.co.uk/buy/belled-exhaust-pipe-taper-seat_1339.htm . The combination of this and the flare at the pipe end means that just a little over half the threads in the port are actually working to keep things together. Anyone have experience with these and care to comment?
Cheers
 
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On the thread I started yesterday about a front iso issue I commented on having to remove the RH exhaust system (for the first time) to remove the iso through-bolt. What I found was:
1. I was amazed at how poorly finished to exhaust port threads are on a FullAuto head. You would slice your finger on the serrated thread tips.
I brushed them with a SS brush to clean of soot. This almost entirely smoothed the thread crowns. I think I will still follow @ludwig s advice on using copper paste.
2. The sealing washer was a machined piece - flat one side with a pronounced dome the other - very like this RGM item https://www.rgmnorton.co.uk/buy/belled-exhaust-pipe-taper-seat_1339.htm . The combination of this and the flare at the pipe end means that just a little over half the threads in the port are actually working to keep things together. Anyone have experience with these and care to comment?
Cheers
You should not needcto pull the header off to remove the iso bolt....it is meant to insert from the left side, nut on the right. Plenty of room left side to withdraw the bolt if needed. The tricky bit is getting a slim open end wrench on the nut against the casing and brackets...but it only needs holding, turning happens on bolt head.
 
Welp. It didn't work out for me. My new longer right exhaust nut, i took out the spacer since it wouldn't tighten down WITH one, added the permatex, followed instructions, cleaned it up while it was drying, fired it up and got it hot, tightened again and it felt damn tight, took a spin with only a couple of back fires, watched it as i ran to the gas station, it looked wobbly and fell off in the parking lot, then i remembered how i burned my hands the last time, so i went in and got a drink and i walked out realizing i'm probably fucked, but i brought the wrench with me at least. so i hid in the bushes and waited until i wouldn't burn my hands and i put it back together and tightened it up, but...i pulled pretty hard with the 14 inch or whatever spanner and it popped em. i got it semi tight again and got it home ok, but i think that might be the end of it for me. it's not gonna hold up without getting an insert. the left side is fine seemingly, with the spacer, the new longer exhaust nut and no goop. it stays tight (and no lock ring) i was excited to only have to carry that wrench around somehow and now i'm bummed thinkin how she's parked indefinitely...this is a sad ending. sorry everybody.
 
Welp. It didn't work out for me. My new longer right exhaust nut, i took out the spacer since it wouldn't tighten down WITH one, added the permatex, followed instructions, cleaned it up while it was drying, fired it up and got it hot, tightened again and it felt damn tight, took a spin with only a couple of back fires, watched it as i ran to the gas station, it looked wobbly and fell off in the parking lot, then i remembered how i burned my hands the last time, so i went in and got a drink and i walked out realizing i'm probably fucked, but i brought the wrench with me at least. so i hid in the bushes and waited until i wouldn't burn my hands and i put it back together and tightened it up, but...i pulled pretty hard with the 14 inch or whatever spanner and it popped em. i got it semi tight again and got it home ok, but i think that might be the end of it for me. it's not gonna hold up without getting an insert. the left side is fine seemingly, with the spacer, the new longer exhaust nut and no goop. it stays tight (and no lock ring) i was excited to only have to carry that wrench around somehow and now i'm bummed thinkin how she's parked indefinitely...this is a sad ending. sorry everybody.
Pop head, box up and send to Precision Machining in Ontario. You'll have it back in a week or so and around $500 USD I'd estimate (dont forget you Yankies get nearly 25% more for your saw-bucks up here, eh!).
 
"bummed thinkin how she's parked indefinitely...this is a sad ending. "




Get busy, pull the head, send it off for repair.
No time for moping.
I feel like that's above my pay grade unfortunately. and i can't afford to have it taken apart. this is not my bike's only issue, i have a bent gear box rod and none of my gaskets are holding oil even when it's not running...debating selling it and getting something i can depend on, that's the sad part. someone else can have fun with her, someone that can afford her.
 
I feel like that's above my pay grade unfortunately. and i can't afford to have it taken apart. this is not my bike's only issue, i have a bent gear box rod and none of my gaskets are holding oil even when it's not running...debating selling it and getting something i can depend on, that's the sad part. someone else can have fun with her, someone that can afford her.
Priorities.

Ramen noodles, mac & cheese, NattyLight, all ways to save money, so your motorcycle can have a better life.

Exhaust nut woes



JK, good luck.
 
I feel like that's above my pay grade unfortunately. and i can't afford to have it taken apart. this is not my bike's only issue, i have a bent gear box rod and none of my gaskets are holding oil even when it's not running...debating selling it and getting something i can depend on, that's the sad part. someone else can have fun with her, someone that can afford her.
Seems like you brought the wrong bike for you, but then you don't learn about your own bike if you are not willing to work on it, gaskets are easy to replace, some think buying a 50 year old British bike and not expect to do any work on them, it's all about owning a classic bike, even fully restored classics need caring and maintenance along the way, and you can't trust someone else to do the work, most things happen when out on the road, as you found out.
Selling it to someone who will take it on as long as the price is right, asking a high price for something that needs work is another thing.
 
I had next to zero hands on mechanical experience 3 years ago. I bought my Commando in March '21. I had starter, primary and clutch problems and sorted them with help from this forum. A few minor issues followed, including a split front rim.

Last year I bought a 1976 CB750. I restored it last winter. So, in 3 years I've gone from no clue to engine out, bare frame renovation. I've rebuilt 2 wheels now, replaced a cylinder head from ebay, replaced fork stanchions, steering bearings, replaced front brakes, loads of stuff and lost count of the number of times carbs have been apart. Friends are bringing bikes over for a bit of help now.

It is possible to teach old dogs new tricks! I'm still only scratching the surface, much I'm still ignorant on, but confidence has grown. Had a few dents on the journey, though. Things I didn't understand and mistakes I've made. That's when I've appreciated friendly advice and reassurance. Then grit teeth, convince yourself you can do it and go again. I've come to massively enjoy working on bikes as an extra dimension to my biking hobby.

If you have any practical bent and patience, you'll pick it up. If you really want the bike and love riding, that will motivate you when you have the moments you feel overwhelmed. Get help here to work through things you don't understand and when you sort a problem, the next ride is incredible. 👍
 
Hello there,
Has anyone had any luck with gooping up your exhaust port threads with high-heat jb weld and tapping new threads with a 1 15/16 tap? I am at my wits end with my 74 850 exhaust nuts. I can't afford to take the head off and ship it to mass. for those brass inserts. Thank for any information.
Do you want to sell it ? And where is it at?
 
This is where we’re all supposed to chip in with overwhelming enthusiasm and encouragement to tear into it and restore it.

But the world is full of abandoned enthusiastically torn down old bikes, so some contemplation would be wise.

Honestly, getting your Norton to a good standard is going to take time, money and inclination. Do not under estimate this.

On the other hand, they're actually remarkably simple bikes and are not challenging to work on, so you do not need to be an ‘expert’ and when you do get stuck, this forum does have some great experts who are very willing to help. I was a complete Norton novice when I bought my Commando, and this site was invaluable in helping me.

BUT you DO need a reasonable level of mechanical competence, ie to be someone who is reasonably experienced at working with, and fixing, bikes and / or other mechanical stuff.

So you most likely can do it IF you want to, and you’ll learn a lot and have a tremendous sense of satisfaction when done.

But honestly only you can decide if you have the required levels of spare time, money and inclination that it WILL need.
 
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