'72 Norton bogs down after less than 10 miles - need ideas!
- Thread starter PJ Martel
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Re: '72 Norton bogs down after less than 10 miles - need ide
Mayby the crackcase's arn't venting? pressure builds up, motor slows..stop and case vents slowly. off you go again...just a tanners worth.
Mayby the crackcase's arn't venting? pressure builds up, motor slows..stop and case vents slowly. off you go again...just a tanners worth.
Re: '72 Norton bogs down after less than 10 miles - need ide
The 13.12 at 4000 doesn't seem particularly robust to me, especially with the "needy" Boyer. Anything below 4000 could be assumed as less voltage than that. A good battery will recover after sitting a few minutes to where it would run again.
The charging system is rather simple in nature and checking all connection and functions should be straight forward.
Check your voltage under loads isolating head light, brake lights, horn, etc., looking for a drop in voltage signifying a poor connection at any particular entity, ie brake light, brake light switch, horn, etc.
Check A/C current of stator before regulator/rectifier and of course D/C after reg/rec.
Both coils going out together is not that common, possible but not common.
PJ Martel said:
The 13.12 at 4000 doesn't seem particularly robust to me, especially with the "needy" Boyer. Anything below 4000 could be assumed as less voltage than that. A good battery will recover after sitting a few minutes to where it would run again.
The charging system is rather simple in nature and checking all connection and functions should be straight forward.
Check your voltage under loads isolating head light, brake lights, horn, etc., looking for a drop in voltage signifying a poor connection at any particular entity, ie brake light, brake light switch, horn, etc.
Check A/C current of stator before regulator/rectifier and of course D/C after reg/rec.
Both coils going out together is not that common, possible but not common.
Deets55
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Re: '72 Norton bogs down after less than 10 miles - need ide
This might be a stretch, but I saw something similar to this on my buddies Triumph . Turns out his valves were adjusted to tight. When his engine warmed up it would run bad once it cooled down it was fine. Might be worth a look.
This might be a stretch, but I saw something similar to this on my buddies Triumph . Turns out his valves were adjusted to tight. When his engine warmed up it would run bad once it cooled down it was fine. Might be worth a look.
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Re: '72 Norton bogs down after less than 10 miles - need ide
To hell with the Triumph gods!!
You have made the right decision.
I don't think it can possibly be a fuel issue if it runs well for some miles then trouble starts. Then runs well afterwards.
Sounds definitely an electrical issue associated with heat. Coils breaking down was not uncommon, but your new single one I wouldn't think would be affected. But how new is everything?
It might be one of those frustrating tedious replace item by item issues.
But boy it is sweet when you discover it. I had similar way back with the Dominator. Finally finally traced it to a hair line crack in the distributor cap. But that obviously won't be your issue.
Maybe upgrade from Boyer to Tri-Spark and hit two stones with the one bird.
Or give up like me, hand it to the bike shop, and get some sleep. Sounds like you've covered a lot of problem solving already.
Good luck PJ. You'll love the Norton like no Triumph when you sort this little issue.
The Triumph gods got their chariot all wrong!
Phil
PJ Martel said:
To hell with the Triumph gods!!
You have made the right decision.
I don't think it can possibly be a fuel issue if it runs well for some miles then trouble starts. Then runs well afterwards.
Sounds definitely an electrical issue associated with heat. Coils breaking down was not uncommon, but your new single one I wouldn't think would be affected. But how new is everything?
It might be one of those frustrating tedious replace item by item issues.
But boy it is sweet when you discover it. I had similar way back with the Dominator. Finally finally traced it to a hair line crack in the distributor cap. But that obviously won't be your issue.
Maybe upgrade from Boyer to Tri-Spark and hit two stones with the one bird.
Or give up like me, hand it to the bike shop, and get some sleep. Sounds like you've covered a lot of problem solving already.
Good luck PJ. You'll love the Norton like no Triumph when you sort this little issue.
The Triumph gods got their chariot all wrong!
Phil
Re: '72 Norton bogs down after less than 10 miles - need ide
Gents,
I certainly appreciate all of the input you've given me and encouragement from Phil. I know once this bug is cured I'll love this bike as the difference between all my Trumps and this bike, both in handling and power is night and day. Being as I'm stuck here at work until tomorrow, I won't be able to go down the checklist of suggestions you've made. I'll answer some of your suggestions with what I know or have already checked. The bike was completely redone by the PO. He only freshened the engine with new gaskets and bolts/nuts/studs etc. There isn't any fastener on the bike that isn't new stainless. The cylinders didn't require any work as they had just been redone (the honing marks were still visible on the cylinders, no scoring at all, compression is excellent). The gearbox was completely redone, and she shifts very smoothly. Tins and frame were taken down and repainted, new brake components, new suspension components,, stainless spokes, new cables - well, you get the idea that this was a pretty complete restoration. And of course, completely new ignition system which includes the Boyer running on a 12v coil and an AGM battery. When I got her I thought it was almost as nicely done as one of my Triumph restorations (the paint on the tins wasn't quite up to my standards, and the kicker would kiss the silencer, but other than that it was very well done).Getting to some of your suggestions and questions: I've set the float to 23mm; I don't believe the floats are damaged, and even if they were the valve wouldn't shut and I'd have fuel shooting out of the float bowl vent, which isn't the case. She won't idle at all when then symptoms begin and will die if I let off the throttle; new petcocks from Mitch Klempf (the good ones that he sells that I've never had any issues with and put on every bike I do), new fuel lines from Old Britts made for the Mikuni (no kinking or collapsing); the carb does have a choke lever which I have only had to use a couple of times on cold start - I did choke it one time when the issues arose and she quickly died; air seals all tight, no crossover tube, no key fob; float chamber is spotless; I believe the crankcase is breathing properly - and after a run get the perverbial drop or 2 of oil out of the pipe; fuel flows freely from the lines even when symptoms occur - no kinks; oil pressure is solid - pump was rebuilt and no wet sumping; I'll check out the voltages and electrical system tomorrow, but I can say that even at idle (when she runs good) I get no light dimming - stays bright no matter the rpm; I checked the valves about 150 miles ago and they were correct, but I'll check again; air filter is a K&N which I cleaned when I cleaned the car. I plan on getting new pilot, main, needle jet and needle tomorrow and replacing the ones in the carb tomorrow if I can find the sizes at a local shop (I pulled a post from last year by Road Scholar and I'll try his recommended sizes). Monday the new Power Arc EI from Old Britts should arrive and I'll be giving that a shot. I have read some good things from some previous threads about the Power Arc - what are some of your guys thoughts on it? Again, thanks for the input and I'll keep you posted
PJ Martel
Gents,
I certainly appreciate all of the input you've given me and encouragement from Phil. I know once this bug is cured I'll love this bike as the difference between all my Trumps and this bike, both in handling and power is night and day. Being as I'm stuck here at work until tomorrow, I won't be able to go down the checklist of suggestions you've made. I'll answer some of your suggestions with what I know or have already checked. The bike was completely redone by the PO. He only freshened the engine with new gaskets and bolts/nuts/studs etc. There isn't any fastener on the bike that isn't new stainless. The cylinders didn't require any work as they had just been redone (the honing marks were still visible on the cylinders, no scoring at all, compression is excellent). The gearbox was completely redone, and she shifts very smoothly. Tins and frame were taken down and repainted, new brake components, new suspension components,, stainless spokes, new cables - well, you get the idea that this was a pretty complete restoration. And of course, completely new ignition system which includes the Boyer running on a 12v coil and an AGM battery. When I got her I thought it was almost as nicely done as one of my Triumph restorations (the paint on the tins wasn't quite up to my standards, and the kicker would kiss the silencer, but other than that it was very well done).Getting to some of your suggestions and questions: I've set the float to 23mm; I don't believe the floats are damaged, and even if they were the valve wouldn't shut and I'd have fuel shooting out of the float bowl vent, which isn't the case. She won't idle at all when then symptoms begin and will die if I let off the throttle; new petcocks from Mitch Klempf (the good ones that he sells that I've never had any issues with and put on every bike I do), new fuel lines from Old Britts made for the Mikuni (no kinking or collapsing); the carb does have a choke lever which I have only had to use a couple of times on cold start - I did choke it one time when the issues arose and she quickly died; air seals all tight, no crossover tube, no key fob; float chamber is spotless; I believe the crankcase is breathing properly - and after a run get the perverbial drop or 2 of oil out of the pipe; fuel flows freely from the lines even when symptoms occur - no kinks; oil pressure is solid - pump was rebuilt and no wet sumping; I'll check out the voltages and electrical system tomorrow, but I can say that even at idle (when she runs good) I get no light dimming - stays bright no matter the rpm; I checked the valves about 150 miles ago and they were correct, but I'll check again; air filter is a K&N which I cleaned when I cleaned the car. I plan on getting new pilot, main, needle jet and needle tomorrow and replacing the ones in the carb tomorrow if I can find the sizes at a local shop (I pulled a post from last year by Road Scholar and I'll try his recommended sizes). Monday the new Power Arc EI from Old Britts should arrive and I'll be giving that a shot. I have read some good things from some previous threads about the Power Arc - what are some of your guys thoughts on it? Again, thanks for the input and I'll keep you posted
PJ Martel
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Re: '72 Norton bogs down after less than 10 miles - need ide
PJ
Sounds like you've spent more time hunting the problem than the whole restoration project took. This is the curliest one I have heard of. I still can't imagine it is a fuel problem but I am just a Norton rider come occasional problem solver/ fixer when something goes wrong, certainly not an expert. The answer is out there somewhere. Or in there, I should say. Pics when you get a moment PJ, everybody loves pics. And as a VIP member, you no doubt realise that is a simple matter of computer straight to post. And thanks on that matter, certainly not my business but I'm sure Jerry appreciates help in keeping the show on the road.
I will be extremely interested to hear what has been causing the problem. It might happen to me one day, or anyone else.
Phil
PJ Martel said:
PJ
Sounds like you've spent more time hunting the problem than the whole restoration project took. This is the curliest one I have heard of. I still can't imagine it is a fuel problem but I am just a Norton rider come occasional problem solver/ fixer when something goes wrong, certainly not an expert. The answer is out there somewhere. Or in there, I should say. Pics when you get a moment PJ, everybody loves pics. And as a VIP member, you no doubt realise that is a simple matter of computer straight to post. And thanks on that matter, certainly not my business but I'm sure Jerry appreciates help in keeping the show on the road.
I will be extremely interested to hear what has been causing the problem. It might happen to me one day, or anyone else.
Phil
Re: '72 Norton bogs down after less than 10 miles - need ide
At the risk of being shouted down by all the experts. What's being described sounds exactly like condenser failure, does your ignition system have condensers? best of luck. It happened to me, first on my Gold Star, second on the Tiger 100 that succeeded the Goldie. Of course on a proper ignition system a condenser failure was easy to overcome.
cheers
wakeup
At the risk of being shouted down by all the experts. What's being described sounds exactly like condenser failure, does your ignition system have condensers? best of luck. It happened to me, first on my Gold Star, second on the Tiger 100 that succeeded the Goldie. Of course on a proper ignition system a condenser failure was easy to overcome.
cheers
wakeup
Fast Eddie
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Re: '72 Norton bogs down after less than 10 miles - need ide
Have you checked your fuel taps?
One possible cause of fuel starvation is poor quality and / or partially obstructed fuel taps. I've seen lots of taps where even when fully on, there's only a partial hole open due to poor machining / assembly. Plus those taps with that have a cylindrical rubber seal inside can suffer from the rubber swelling and, again, partially blocking the hole.
Partially blocked taps can fool us because when we open them, fuel comes out, and things run well in the workshop. But if they cannot keep up with the engine, the float bowls empty and cause issues. Then they refill again, leading us to think the problem is elsewhere!
Have you checked your fuel taps?
One possible cause of fuel starvation is poor quality and / or partially obstructed fuel taps. I've seen lots of taps where even when fully on, there's only a partial hole open due to poor machining / assembly. Plus those taps with that have a cylindrical rubber seal inside can suffer from the rubber swelling and, again, partially blocking the hole.
Partially blocked taps can fool us because when we open them, fuel comes out, and things run well in the workshop. But if they cannot keep up with the engine, the float bowls empty and cause issues. Then they refill again, leading us to think the problem is elsewhere!
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Re: '72 Norton bogs down after less than 10 miles - need ide
Eddie
Read his info mate. You are giving him duff he has already covered.
Phil
Fast Eddie said:
Eddie
Read his info mate. You are giving him duff he has already covered.
Phil
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Re: '72 Norton bogs down after less than 10 miles - need ide
I agree that the symptoms are electrical. IMO, the battery voltage/Boyer/coil is a high on the list of "usual suspects." Unfortunately, unless you have another ignition system handy, it's difficult to troubleshoot. Do you have the oem points/AAU you could try? I had major similar problems with my bike when purchased but replacing the Boyer/single coil with the oem ignition system cured the problems. In fact, I had no intention of ever replacing the points/AAU with another electronic but the Trispark sounded intriguing so, after several years on the points/AAU I decided to try one and it's been in there ever since. The advantage to the points/AAU is it's very INsensitive to low voltage - the advance can't change if battery voltage is low!
Have you checked all relevant connections/wires? Could be a simple case of poor connections that vary with engine heat.
I agree that the symptoms are electrical. IMO, the battery voltage/Boyer/coil is a high on the list of "usual suspects." Unfortunately, unless you have another ignition system handy, it's difficult to troubleshoot. Do you have the oem points/AAU you could try? I had major similar problems with my bike when purchased but replacing the Boyer/single coil with the oem ignition system cured the problems. In fact, I had no intention of ever replacing the points/AAU with another electronic but the Trispark sounded intriguing so, after several years on the points/AAU I decided to try one and it's been in there ever since. The advantage to the points/AAU is it's very INsensitive to low voltage - the advance can't change if battery voltage is low!
Have you checked all relevant connections/wires? Could be a simple case of poor connections that vary with engine heat.
Fast Eddie
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Re: '72 Norton bogs down after less than 10 miles - need ide
Well Phil, I see a comment about fitting new taps, but no comment that they've been checked. I agree its a long shot, but its certainly not impossible that they're faulty, as I have found out myself in the past!
phil yates said:
Well Phil, I see a comment about fitting new taps, but no comment that they've been checked. I agree its a long shot, but its certainly not impossible that they're faulty, as I have found out myself in the past!
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Re: '72 Norton bogs down after less than 10 miles - need ide
fuel flows freely from the lines even when symptoms occur - no kinks
I wasn't intending to sound smart Eddie. You must have missed this. Not hard, given what poor PJ listed as things he looked at. But I have noticed this before that lots of suggestions come in covering issues already checked. I know everyone is trying to be helpful.
I can't imagine fuel being the issue here at all. The symptoms just don't match it. I think mike996 is shooting in the right direction. Just has to be something like this. That hair line crack I mentioned in the Dominator dissy cap, diagnosis took me bloody weeks. It was opening up a fraction when hot, almost impossible to see when cold. I thought the Triumph god's had me by the short and curly's too, just for daring to buy this old Norton. There was no forum then to ask what the f…….??
I can't even remember how I discovered it. But man, was it a relief to get that old bird running properly again.
Now don't ask me about the combat. If I wasn't a mechanic then, I quickly became one!!
Phil
Fast Eddie said:
fuel flows freely from the lines even when symptoms occur - no kinks
I wasn't intending to sound smart Eddie. You must have missed this. Not hard, given what poor PJ listed as things he looked at. But I have noticed this before that lots of suggestions come in covering issues already checked. I know everyone is trying to be helpful.
I can't imagine fuel being the issue here at all. The symptoms just don't match it. I think mike996 is shooting in the right direction. Just has to be something like this. That hair line crack I mentioned in the Dominator dissy cap, diagnosis took me bloody weeks. It was opening up a fraction when hot, almost impossible to see when cold. I thought the Triumph god's had me by the short and curly's too, just for daring to buy this old Norton. There was no forum then to ask what the f…….??
I can't even remember how I discovered it. But man, was it a relief to get that old bird running properly again.
Now don't ask me about the combat. If I wasn't a mechanic then, I quickly became one!!
Phil
Fast Eddie
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Re: '72 Norton bogs down after less than 10 miles - need ide
fuel flows freely from the lines even when symptoms occur - no kinks
I wasn't intending to sound smart Eddie. You must have missed this. Not hard, given what poor PJ listed as things he looked at. But I have noticed this before that lots of suggestions come in covering issues already checked. I know everyone is trying to be helpful.
I can't imagine fuel being the issue here at all. The symptoms just don't match it. I think mike996 is shooting in the right direction. Just has to be something like this. That hair line crack I mentioned in the Dominator dissy cap, diagnosis took me bloody weeks. It was opening up a fraction when hot, almost impossible to see when cold. I thought the Triumph god's had me by the short and curly's too, just for daring to buy this old Norton. There was no forum then to ask what the f…….??
I can't even remember how I discovered it. But man, was it a relief to get that old bird running properly again.
Now don't ask me about the combat. If I wasn't a mechanic then, I quickly became one!!
Phil[/quote]
I didn't take you as trying to be smart Phil... Not this time :wink:
It could well turn out to be electrical, I agree. But, and I know I sound like a stuck record, unless he knows what "flowing freely" actually looks like from a known good fuel tap, I'm afraid I still say its possible!
The first rule in this kind of situation is to properly ensure the basics are ok before looking at the complex / expensive stuff.
The guy has already ordered a new ign system. If that doesn't work he could easily spend fortunes in time and money on this. Just imagine if after doing all of this, he then finds out it was the taps!
I posted a confession a while back about the time I started stripping the carbs down on a racer before realising I'd simply run out of fuel
Whilst I'm sure this chap is not as thick as me, the point remains.
Lets see what our man finds. And soon I hope!
fuel flows freely from the lines even when symptoms occur - no kinks
I wasn't intending to sound smart Eddie. You must have missed this. Not hard, given what poor PJ listed as things he looked at. But I have noticed this before that lots of suggestions come in covering issues already checked. I know everyone is trying to be helpful.
I can't imagine fuel being the issue here at all. The symptoms just don't match it. I think mike996 is shooting in the right direction. Just has to be something like this. That hair line crack I mentioned in the Dominator dissy cap, diagnosis took me bloody weeks. It was opening up a fraction when hot, almost impossible to see when cold. I thought the Triumph god's had me by the short and curly's too, just for daring to buy this old Norton. There was no forum then to ask what the f…….??
I can't even remember how I discovered it. But man, was it a relief to get that old bird running properly again.
Now don't ask me about the combat. If I wasn't a mechanic then, I quickly became one!!
Phil[/quote]
I didn't take you as trying to be smart Phil... Not this time :wink:
It could well turn out to be electrical, I agree. But, and I know I sound like a stuck record, unless he knows what "flowing freely" actually looks like from a known good fuel tap, I'm afraid I still say its possible!
The first rule in this kind of situation is to properly ensure the basics are ok before looking at the complex / expensive stuff.
The guy has already ordered a new ign system. If that doesn't work he could easily spend fortunes in time and money on this. Just imagine if after doing all of this, he then finds out it was the taps!
I posted a confession a while back about the time I started stripping the carbs down on a racer before realising I'd simply run out of fuel
Whilst I'm sure this chap is not as thick as me, the point remains.
Lets see what our man finds. And soon I hope!
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Re: '72 Norton bogs down after less than 10 miles - need ide
I didn't take you as trying to be smart Phil... Not this time :wink:
It could well turn out to be electrical, I agree. But, and I know I sound like a stuck record, unless he knows what "flowing freely" actually looks like from a known good fuel tap, I'm afraid I still say its possible!
The first rule in this kind of situation is to properly ensure the basics are ok before looking at the complex / expensive stuff.
The guy has already ordered a new ign system. If that doesn't work he could easily spend fortunes in time and money on this. Just imagine if after doing all of this, he then finds out it was the taps!
I posted a confession a while back about the time I started stripping the carbs down on a racer before realising I'd simply run out of fuel
Whilst I'm sure this chap is not as thick as me, the point remains.
Lets see what our man finds. And soon I hope![/quote]
If it turns out to be the taps Eddie, you will be given a leave pass to write any and every post you want.
I'll say I knew it all along, was only kidding about electrics
It's a bastard problem Eddie. We just want PJ to enjoy his Norton.
He can find out later what a bastard/frustrating/unreliable/expensive piece of kit they are.
Once you get to love them, there is no turning back.
Like a bad marriage, too expensive to get out of.
But I jest, of course.
Or do I?
Cheers
Phil
Fast Eddie said:
I didn't take you as trying to be smart Phil... Not this time :wink:
It could well turn out to be electrical, I agree. But, and I know I sound like a stuck record, unless he knows what "flowing freely" actually looks like from a known good fuel tap, I'm afraid I still say its possible!
The first rule in this kind of situation is to properly ensure the basics are ok before looking at the complex / expensive stuff.
The guy has already ordered a new ign system. If that doesn't work he could easily spend fortunes in time and money on this. Just imagine if after doing all of this, he then finds out it was the taps!
I posted a confession a while back about the time I started stripping the carbs down on a racer before realising I'd simply run out of fuel
Whilst I'm sure this chap is not as thick as me, the point remains.
Lets see what our man finds. And soon I hope![/quote]
If it turns out to be the taps Eddie, you will be given a leave pass to write any and every post you want.
I'll say I knew it all along, was only kidding about electrics
It's a bastard problem Eddie. We just want PJ to enjoy his Norton.
He can find out later what a bastard/frustrating/unreliable/expensive piece of kit they are.
Once you get to love them, there is no turning back.
Like a bad marriage, too expensive to get out of.
But I jest, of course.
Or do I?
Cheers
Phil
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