Puzzling misfiring from one piston

kommando said:
I worked in an engine assembly plant making 5000 engines a week, no assembly lube used on the camshafts.
Click to expand...
I'm pretty sure the whole magic oil and "two grand for 20 mins" originated for racing engines with flat tappets.
Stiff valve springs challenged the oil film, and 2,000 RPM was to ensure a hydrodynamic condition until the high spots were cuffed off.
Aftermarket cam makers protecting their (warranty) interests.
It has trickled down to everything now.

The width of the cam lobe is key.
The PD TDI engines are a great example.
 
Just look at this seat, and the excuse, oh its and Italian Frame !!

www.accessnorton.com

Rougue commando seat !

Can anyone identefy this seat ? Sold to me by norvil for a mk3 roadster 10 years ago and it obviously isn't !!! As new still except might need a bit of light sanding and plasticote . Told I had a rogue italian frame and wouldn't take it back ! Cheap if anyone wants it by the way. Wassel brand.
www.accessnorton.com www.accessnorton.com

All RGM and AN say about new cams is to fit with new or regound followers.

 
OK, better way to ease your mind. Before you next start it, drain the sump. Then pour about a cup of oil in each exhaust rocker area. If using Castrol GTX 20W50, get the same oil but marked Classic (high Zinc) to do it.

When I build engines, I use the Classic version to start and then switch to the non-classic version at the first oil change. It would be fine to use it all the time, just more expensive and harder to find.

Why Castrol GTX? It's dino oil - I don't prefer synthetic in old bikes. It is on the Norton and Triumph recommended lists (yes, I know things change over 50 years), it's readily available at a decent price, and I've used it since it was introduced. They also now have full synthetic which I do not use - supposedly better, but oil is not tested in 50 year old engines - and our engines are nothing like a modern water-cooled engines!
 
kommando said:
I worked in an engine assembly plant making 5000 engines a week, no assembly lube used on the camshafts.
Click to expand...
AN cams come with a "special" cam lube that reminds me of STP. Hepolite cams (what I normally use), come with nothing and say nothing. I do use assembly lube on the lobes, and I ensure that the bushings are well lubed with oil during assembly. I also dump some oil in the exhaust rocker area. I don't consider any of that to be critically needed - it's just a little extra protection for the first few minutes of running before being able to ride.

To me, grinding (when needed) and polishing the tappet surfaces is much more important when not using new.
 
kommando said:
Just look at this seat, and the excuse, oh its and Italian Frame !!

www.accessnorton.com

Rougue commando seat !

Can anyone identefy this seat ? Sold to me by norvil for a mk3 roadster 10 years ago and it obviously isn't !!! As new still except might need a bit of light sanding and plasticote . Told I had a rogue italian frame and wouldn't take it back ! Cheap if anyone wants it by the way. Wassel brand.
www.accessnorton.com www.accessnorton.com

All RGM and AN say about new cams is to fit with new or regound followers.

Click to expand...
I have no dog in this fight.


Rather than try and steer the original poster away from, or toward this particular "sacred cow" topic, I offered two solutions for what is clearly obvious to any experienced tuner, a no-load cracked throttle intermittent misfire, which is likely to be a NON-issue when riding, or idling the engine as designed.

The whole "break-in" topic has been beaten to death, and I have no interest in trying to "sell"
my methods.

I have a Norvil cam in my engine currently, based solely on a @dynodave verbal recommendation.
ALL the parts from all suppliers are suspect in my experience.


I'll let you know how it lasts (only 10,000 miles so far)
 
marshg246 said:
OK, better way to ease your mind. Before you next start it, drain the sump. Then pour about a cup of oil in each exhaust rocker area. If using Castrol GTX 20W50, get the same oil but marked Classic (high Zinc) to do it.

When I build engines, I use the Classic version to start and then switch to the non-classic version at the first oil change. It would be fine to use it all the time, just more expensive and harder to find.

Why Castrol GTX? It's dino oil - I don't prefer synthetic in old bikes. It is on the Norton and Triumph recommended lists (yes, I know things change over 50 years), it's readily available at a decent price, and I've used it since it was introduced. They also now have full synthetic which I do not use - supposedly better, but oil is not tested in 50 year old engines - and our engines are nothing like a modern water-cooled engines!
Click to expand...
I use the Castrol GTX Classic 20/50. In recent oil testing the regular gtx produced 80 ppm metal on analysis whereas the classic gtx produced 30ppm in the same engine for the same duration and loading.
These oils are changing all the time and the regular GTX lost some more of its zddp about 2 years ago. That loss of zddp prompted the testing and comparison.
The classic is cheap , though not quite as cheap as regular GTX, and is designed for our old flat tappet, non catalytic engines. The regular GTX keeps getting reformulated so that it will work with modern catalytic engines.

The classic GTX is very similar in chemical makeup to Castrol Classic XL , which is readily available in the UK and Europe, but difficult to find in North America. No problem as we have the GTX Classic.
Jim Comstock tested the Castrol Classic XL 20/50 and it did very well, top tier Iirc.
GTX also protected well in his test, but that was the old recipe GTX, not what is currently on offer. GTX had very high heat from friction, not a good thing. In Jim's testing the GTX was at 7.70 for heat from friction. This was the greatest amount of heat produced out of the 86 oil types tested. This would be a concern for hot weather riding. It did offer reasonable protection at 257.

Castrol Classic XL did not have high heat from friction , it was at 1.94, one of the lowest of the conventional oils which Jim tested. At 333 for protection it also scored higher than regular GTX. Jim did not test Castol GTX Classic. I'm not sure if it was available then?
With near identical chemistry to the UK Castrol Classic XL, I think it's a safe bet that the Castrol GTX Classic 20/50 would put up numbers similar to the top tier Castrol Classic XL in Jim's test.
We also have the oil analysis testing of the GTX Classic, which showed very low PPM metal in a working engine, perhaps the best test of all.
Hope all of this makes sense as it's discussing 3 different oils with very similar names and all Castrol branded. I suppose it is actually 4 oils as the current GTX is a different oil to the one in Jim's test. My guess is that it would score lower on the protection score than Jim's GTX but might still have the heat problem.

Glen
 
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Semitone said:
Hello again o0norton0o. Thanks for chiming in. No, that sporadic combustion sound sounded totally normal. I probably had it running for a total of 30 seconds or the course of 15 minutes. The right header was a bit warm to touch, the left cool. So I’ve got more into. After work I went over to the bike and rechecked tappet clearances. I was disturbed to see that at TDC on compression stroke, there was no lash between rod and rocker. In fact I had to back off the adjuster screw about 4 turns before I heard a “ping”. I think the rod was not seated properly. I’ve taken the head off many times over the years, and I’m usually very careful about making sure rods are seated properly before tightening head. Anyway, I set gap and checked others, which were fine. So I hope I didn’t damage the cam, follower, etc. during the short time I had it running. I checked compression and it was still at 120psi as it was yesterday. I’m not sure how I got this much compression yesterday with the intake rocker in the state it was in. Nevertheless I hope this was the cause of the misfiring issue. Unfortunately i didn’t have time to start the engine! Hopefully tomorrow.
Click to expand...
Well, dude, THERE was a good reason to have a misfire.
 
concours said:
I have no dog in this fight.


Rather than try and steer the original poster away from, or toward this particular "sacred cow" topic, I offered two solutions for what is clearly obvious to any experienced tuner, a no-load cracked throttle intermittent misfire, which is likely to be a NON-issue when riding, or idling the engine as designed.

The whole "break-in" topic has been beaten to death, and I have no interest in trying to "sell"
my methods.

I have a Norvil cam in my engine currently, based solely on a @dynodave verbal recommendation.
ALL the parts from all suppliers are suspect in my experience.


I'll let you know how it lasts (only 10,000 miles so far)
Click to expand...
I forgot to add in my initial post that I tried starting without the choke and when it kicked over, there was no combustion at all from the right side at all. Did you see my post yesterday? Discovered that intake manifold pushrod for that cylinder was not seated properly. Haven’t had time to start it after fixing this, but I expect this was the issue. Anyway since yesterday Ive looked at several posts on the whole break-in subject, and agree it has been beaten to death, and I have to say I’m farther from a conclusion than I was before I went down the rabbit holes. The cam is Norvil fwiw. Thanks
 
marshg246 said:
AN cams come with a "special" cam lube that reminds me of STP. Hepolite cams (what I normally use), come with nothing and say nothing. I do use assembly lube on the lobes, and I ensure that the bushings are well lubed with oil during assembly. I also dump some oil in the exhaust rocker area. I don't consider any of that to be critically needed - it's just a little extra protection for the first few minutes of running before being able to ride.

To me, grinding (when needed) and polishing the tappet surfaces is much more important when not using new.
Click to expand...
I did pour oil over rockers a few times to get as much oil on the followers and cam as I could. I did not change the followers. They had almost no wear, so I just did a light grind and polish.
 
Semitone said:
I forgot to add in my initial post that I tried starting without the choke and when it kicked over, there was no combustion at all from the right side at all. Did you see my post yesterday? Discovered that intake manifold pushrod for that cylinder was not seated properly. Haven’t had time to start it after fixing this, but I expect this was the issue. Anyway since yesterday Ive looked at several posts on the whole break-in subject, and agree it has been beaten to death, and I have to say I’m farther from a conclusion than I was before I went down the rabbit holes. The cam is Norvil fwiw. Thanks
Click to expand...
Correction:… no combustion from the LEFT side…
 
Semitone said:
Hello again o0norton0o. Thanks for chiming in. No, that sporadic combustion sound sounded totally normal. I probably had it running for a total of 30 seconds or the course of 15 minutes. The right header was a bit warm to touch, the left cool. So I’ve got more into. After work I went over to the bike and rechecked tappet clearances. I was disturbed to see that at TDC on compression stroke, there was no lash between rod and rocker. In fact I had to back off the adjuster screw about 4 turns before I heard a “ping”. I think the rod was not seated properly. I’ve taken the head off many times over the years, and I’m usually very careful about making sure rods are seated properly before tightening head. Anyway, I set gap and checked others, which were fine. So I hope I didn’t damage the cam, follower, etc. during the short time I had it running. I checked compression and it was still at 120psi as it was yesterday. I’m not sure how I got this much compression yesterday with the intake rocker in the state it was in. Nevertheless I hope this was the cause of the misfiring issue. Unfortunately i didn’t have time to start the engine! Hopefully tomorrow.
Click to expand...
All that is visually discernable.

Had you rolled it over with the plugs out, via the kicker, by hand, feeling and listening for abnormalities?

SOP engine assembly.
 
concours said:
All that is visually discernable.

Had you rolled it over with the plugs out, via the kicker, by hand, feeling and listening for abnormalities?

SOP engine assembly.
Click to expand...
Yes, hand cranked initially, then once I had the gearbox back in and primary, kicked it over. Everything looked, felt and smelled right..
 
worntorn said:
I use the Castrol GTX Classic 20/50. In recent oil testing the regular gtx produced 80 ppm metal on analysis whereas the classic gtx produced 30ppm in the same engine for the same duration and loading.
These oils are changing all the time and the regular GTX lost some more of its zddp about 2 years ago. That loss of zddp prompted the testing and comparison.
The classic is cheap , though not quite as cheap as regular GTX, and is designed for our old flat tappet, non catalytic engines. The regular GTX keeps getting reformulated so that it will work with modern catalytic engines.

The classic GTX is very similar in chemical makeup to Castrol Classic XL , which is readily available in the UK and Europe, but difficult to find in North America. No problem as we have the GTX Classic.
Jim Comstock tested the Castrol Classic XL 20/50 and it did very well, top tier Iirc.
GTX also protected well in his test, but that was the old recipe GTX, not what is currently on offer. GTX had very high heat from friction, not a good thing. In Jim's testing the GTX was at 7.70 for heat from friction. This was the greatest amount of heat produced out of the 86 oil types tested. This would be a concern for hot weather riding. It did offer reasonable protection at 257.

Castrol Classic XL did not have high heat from friction , it was at 1.94, one of the lowest of the conventional oils which Jim tested. At 333 for protection it also scored higher than regular GTX. Jim did not test Castol GTX Classic. I'm not sure if it was available then?
With near identical chemistry to the UK Castrol Classic XL, I think it's a safe bet that the Castrol GTX Classic 20/50 would put up numbers similar to the top tier Castrol Classic XL in Jim's test.
We also have the oil analysis testing of the GTX Classic, which showed very low PPM metal in a working engine, perhaps the best test of all.
Hope all of this makes sense as it's discussing 3 different oils with very similar names and all Castrol branded. I suppose it is actually 4 oils as the current GTX is a different oil to the one in Jim's test. My guess is that it would score lower on the protection score than Jim's GTX but might still have the heat problem.

Glen
Click to expand...
Trying to figure out how this GTX side bar started. Incidentally, I’ve been using Castrol for many years in my bikes and cats, Can’t remember what I was that started my brand loyalty, but there you go.
 
Semitone said:
I forgot to add in my initial post that I tried starting without the choke and when it kicked over, there was no combustion at all from the right side at all. Did you see my post yesterday? Discovered that intake manifold pushrod for that cylinder was not seated properly. Haven’t had time to start it after fixing this, but I expect this was the issue. Anyway since yesterday Ive looked at several posts on the whole break-in subject, and agree it has been beaten to death, and I have to say I’m farther from a conclusion than I was before I went down the rabbit holes. The cam is Norvil fwiw. Thanks
Click to expand...
If by "intake manifold pushrod" you mean that the intake valve pushrod was not properly seated in the tappet and rocker, there should have been a pretty terrible noise and I recommend you take the head off - surely the pushrod is well damaged!
 
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