Fire on the first ride

gatsby

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Another one on the road!
I did start a rebuild thread, and got lazy and did not update. For this bike I tried to spend as little money as possible, and use left over parts from my bin. Its complete basket case made from multiple parts and bike leftovers.

Work included:
Bored over .020
New pistons
Layshaft bearings
Rebuilt forks
Rebuild brake with Madass MC
Stay up floats
All new isolastics / adjustable kit
Electronic ignition
LED headlight
Tires
Wheel bearings
Sealed tank
Bras inserts on head
Valve seals

Grab bar and air box still have to be installed.

During my first ride yesterday, I caught fire. It appears that my 50 year old oil line popped off, and the remainder of the lines melted off. I am guessing the slow moving traffic and an oil starved head caused the engine to over heat and melt the lines. Once I pulled over, the left header pipe ignited on fire. I was able to snuff it out with my leather gloves. Once the bike cooled, I cut the ends of the melted oil lines, and popped them back on with zip ties. I took a route home with few stop lights. When I check the oil when I got home, there was less than half a cup in the sump. A new oil line will be ordered.

Question - I was burning a lot of oil and smoking as this was the first ride bedding in the rings. When I started up the bike again after filling it up with oil, bike was still smoking. I drove about 20 miles. How many miles should I expect smoking?

All the best,
Gatsby



Fire on the first ride
Fire on the first ride
Fire on the first ride
Fire on the first ride
 
Get stainless lines. It's oil delivery which is important. Can't help with your smoking issue but I appreciate you doing what you can to get another old girl back on the road. Cosmetics be damned.
 
Another one on the road!
I did start a rebuild thread, and got lazy and did not update. For this bike I tried to spend as little money as possible, and use left over parts from my bin. Its complete basket case made from multiple parts and bike leftovers.

Work included:
Bored over .020
New pistons
Layshaft bearings
Rebuilt forks
Rebuild brake with Madass MC
Stay up floats
All new isolastics / adjustable kit
Electronic ignition
LED headlight
Tires
Wheel bearings
Sealed tank
Bras inserts on head
Valve seals

Grab bar and air box still have to be installed.

During my first ride yesterday, I caught fire. It appears that my 50 year old oil line popped off, and the remainder of the lines melted off. I am guessing the slow moving traffic and an oil starved head caused the engine to over heat and melt the lines. Once I pulled over, the left header pipe ignited on fire. I was able to snuff it out with my leather gloves. Once the bike cooled, I cut the ends of the melted oil lines, and popped them back on with zip ties. I took a route home with few stop lights. When I check the oil when I got home, there was less than half a cup in the sump. A new oil line will be ordered.

Question - I was burning a lot of oil and smoking as this was the first ride bedding in the rings. When I started up the bike again after filling it up with oil, bike was still smoking. I drove about 20 miles. How many miles should I expect smoking?

All the best,
Gatsby



View attachment 120038View attachment 120039View attachment 120041View attachment 120042
 
A properly rebuilt bike NEVER smokes when first run and My bikes have great compression even before starting them. I run my bikes in my shop and the air is never smoke filled. Do a compression test you should have 150-170 PSI. I never thought you could get oil to burn.
 
When the oil lines melted you lost oil pressure to the big ends, now as long as you did not run out of oil the spinning crank would have still got oil and also the centrifugal force would have got some pressure at the big ends. The lesson being get the stainless braided pipes to ensure the pipes do not break.

The smoke is likely the rings, it should have disappeared within a few hundred yards.
 
A properly rebuilt bike NEVER smokes when first run and My bikes have great compression even before starting them. I run my bikes in my shop and the air is never smoke filled. Do a compression test you should have 150-170 PSI. I never thought you could get oil to burn.
Synthetic does, try it.
 
I’m starting to question if the valve seals I used were too old. They were given to me, and I have no idea how old they were…. I just took it for another run, and it’s only one side smoking.
 
How much oil was left in the oil tank?

Once upon a time my left leg got really warm when I was running down the highway at 70 mph. I looked down and my pant leg was covered in oil and my oil pressure gauge was at 0. I pulled over and the header and head were smoking. Oil pressure gauge line had blown off at the spindle cover. Relatively easy fix on the side of the road, since I at the time carried the parts to eliminate the oil pressure gauge. Oil tank was still almost full, but most of the oil feeding the rockers for a minute or so was sprayed on my leg. Anywho, started it up and took a surface street back home. When I got home I reconnected the oil pressure gauge and checked the oil pressure. I still had plenty of oil pressure. Then I removed that oil pressure gauge. Maybe someday I'll get another one. Someday sometimes never comes though.

Shouldn't smoke unless the sump is filling up to the main bearings when it sits for a few minutes. That is a bit of an exaggeration, but too much oil in the sump can make a Norton engine smoke for a bit.

It is possible that the valve seals are no longer down over the guides all the way and are traveling up and down with the valve. Basically doing nothing.
 
How much oil was left in the oil tank?

Once upon a time my left leg got really warm when I was running down the highway at 70 mph. I looked down and my pant leg was covered in oil and my oil pressure gauge was at 0. I pulled over and the header and head were smoking. Oil pressure gauge line had blown off at the spindle cover. Relatively easy fix on the side of the road, since I at the time carried the parts to eliminate the oil pressure gauge. Oil tank was still almost full, but most of the oil feeding the rockers for a minute or so was sprayed on my leg. Anywho, started it up and took a surface street back home. When I got home I reconnected the oil pressure gauge and checked the oil pressure. I still had plenty of oil pressure. Then I removed that oil pressure gauge. Maybe someday I'll get another one. Someday sometimes never comes though.

Shouldn't smoke unless the sump is filling up to the main bearings when it sits for a few minutes. That is a bit of an exaggeration, but too much oil in the sump can make a Norton engine smoke for a bit.

It is possible that the valve seals are no longer down over the guides all the way and are traveling up and down with the valve. Basically doing nothing.
Always nice to have a happy endings g and get home:). Time to pull the head!
 
I’m starting to question if the valve seals I used were too old. They were given to me, and I have no idea how old they were…. I just took it for another run, and it’s only one side smoking.
The better ones are Viton Rubber, Hi- Heat material. I never used the ones that came in gasket kits and I clearance the valves to guides using Precision Machining recommended specs. I've never seen a seal slip off the guide. But I use PM parts and care when I do my head work= Race quality work.
 
You could have a clog on the head's intake side drain hole. Sometimes a clog there puts the valve underwater (in oil) and it sucks oil past the oil seal where it normally won't do that. You can take the intake valve cover off and it's on the timing side next to the timing side valve. It wouldn't be the first time that passage was clogged and caused a bike to smoke until it was unclogged...... just another thing to check, not a diagnosis from my armchair..
 
Once you get the engine sorted out. I would reconsider those wheels. Rusty spokes can fail if the rust eats enough of the metal. Rusty rims can scuff the tire tube and cause a leak. Old tires can fail and kill you.
 
My 850 took a couple of hundred km's following rebore to 20 thou over. Unclear which oil lines failed here...head feed or to/from tank lines? Unlikely the oil tank lines melted if made from the original material...more likely just hardened and cracked open. The oil lines to/from the tank are not under any real pressures...only the valve head feed lines. These can be replaced with 3mm nylon air brake lines...cheap as chips.
 
The smoke is likely the rings, it should have disappeared within a few hundred yards.
Piston rings are either of the barrel or tapered type. Both need to be fitted with the marked side up. If not done correctly, rings will push oil from the crankcase into the combustion chamber, and the smoking will never disappear.
See figure below.

- Knut

1748825337593.png
 
During my first ride yesterday, I caught fire. It appears that my 50 year old oil line popped off, and the remainder of the lines melted off. I am guessing the slow moving traffic and an oil starved head caused the engine to over heat and melt the lines.
I suggest you replace all the lines, including the fuel line. A spliced fuel line is a disaster waiting to happen! Leaking fuel catching fire would be much harder to put out than a fire caused by leaking oil.

- Knut
 
I agree that it shouldn't be smoking for more than 10-15 seconds after a rebuild as oils/lubricants that were used on the rings/cyl walls is burned off (some builders assemble those dry but that's a different subject).

Is it smoking all the time? Only on acceleration? Only on deceleration/idling?
 
Even with no seals on the inlet valves it should not smoke. Mine worked themselves off once and it used a bit of oil but didn't smoke.
 
Another one on the road!
I did start a rebuild thread, and got lazy and did not update. For this bike I tried to spend as little money as possible, and use left over parts from my bin. Its complete basket case made from multiple parts and bike leftovers.

Work included:
Bored over .020
New pistons
Layshaft bearings
Rebuilt forks
Rebuild brake with Madass MC
Stay up floats
All new isolastics / adjustable kit
Electronic ignition
LED headlight
Tires
Wheel bearings
Sealed tank
Bras inserts on head
Valve seals

Grab bar and air box still have to be installed.

During my first ride yesterday, I caught fire. It appears that my 50 year old oil line popped off, and the remainder of the lines melted off. I am guessing the slow moving traffic and an oil starved head caused the engine to over heat and melt the lines. Once I pulled over, the left header pipe ignited on fire. I was able to snuff it out with my leather gloves. Once the bike cooled, I cut the ends of the melted oil lines, and popped them back on with zip ties. I took a route home with few stop lights. When I check the oil when I got home, there was less than half a cup in the sump. A new oil line will be ordered.

Question - I was burning a lot of oil and smoking as this was the first ride bedding in the rings. When I started up the bike again after filling it up with oil, bike was still smoking. I drove about 20 miles. How many miles should I expect smoking?

All the best,
Gatsby



View attachment 120038View attachment 120039View attachment 120041View attachment 120042
You warmed yourself while almost giving it too much patina
 
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