Barrel coatings test

Havn't read all the comments but a great experiment with an interesting result.
Sure this has been discussed many times but is there a real issue with the temp these motors run at.
I had my 850 motor in a reasonable state of tune in 1976, one of the hottest UK summers.
I thrashed it around all summer, fitted a T150 oil cooler w/out a thermostat only to find that the general consensus was that my motor was running to cool.
Also I don't recall seeing any Commando motors currently within the CRMC with oil coolers.
Before anyone asks, A Black stove enameled motor prepared by Fred Barlow.
Discus!!

Given comnoz's observation re liner temp when fins seemed cool I would suggest any heat reduction for the engine via an oil cooler (also known as heat exchanger) is good heat reduction. Oh, but with a thermostat. Oh, and with engine airflow to be sure.
Your memorable heat wave (http://en.m.wikipedia.org/wiki/1976_Uni ... _heat_wave) is probably close to a warm maybe even hot spring here hence oil cooler country.

Oil coolers on Norton race bikes not needed 120mph wind blast keeps things in check.

peter12 said:

Havn't read all the comments but a great experiment with an interesting result.
Sure this has been discussed many times but is there a real issue with the temp these motors run at.
I had my 850 motor in a reasonable state of tune in 1976, one of the hottest UK summers.
I thrashed it around all summer, fitted a T150 oil cooler w/out a thermostat only to find that the general consensus was that my motor was running to cool.
Also I don't recall seeing any Commando motors currently within the CRMC with oil coolers.
Before anyone asks, A Black stove enameled motor prepared by Fred Barlow.
Discus!!

Click to expand...

Only place our oil gets too hot is in the head. Last yr comnoz tested his double large cooller inline with head feed to find where cooler works best. Coolling over heated head oil in bulk after its mixed with cooler oil in in tank vs extra coolling of oil before its head boiled is my question that was answered.
Comnoz you musta run into rain at turn pike heating speeds, - what did your head and oil temps show?

Painted vs raw alu intercooler, skip to 9 min for punch line.
https://www.youtube.com/watch?v=z_mmmXTbLP0

I can not find anything that's shows any advantage of external heat-raditive coating helping items -unless heated to glowing temps.

Jim
Good test, now we dont need to spend silly money on hi-tec coatings. Just simple Hi-temp black.

peter12 said:

Sure this has been discussed many times but is there a real issue with the temp these motors run at.

Click to expand...

Rather than join in on this rather egg headed discussion, my own answer to this question is "no". Continue to drive your selves nuts pursuing a few degree drop in engine operating temp at the extreme then do the same to keep the engine warm enough during cold rides. It's an air cooled engine for crying out loud! No antifreeze to boil over and with a good motor oil, syn or otherwise the engine will still get lubed. The operating temps will vary. That's all I got. :mrgreen:

Jim has showed what Norton already knew that there's more than enough mass/surface area for the hp sold for public use no matter what reasonable finish applied but we still hear of over heating tales form those in extreme conditions in public or all out racers so there may be some special cases finish can make a difference, though still up in the air it there is one vs raw dull rough metal surface. Alas any surface finish can only help a little bit & mainly only when approaching incandescent temps. Sir Eddie made provisions for extra coolling with fins and ducting -so will rig up similar ducting for comnoz to test Peel with & w/o. I expect so little an effect Peel gets external and internal watering plus oil cooler for head oil. Leaving steam trails instead of oil smoke and flames.

I had a couple reasons for doing the coatings test.

First, I recondition batches of barrels for CNW and others and I had a dozen of them waiting. The past several years I have been using [aerospace] heat dissipating coating on the barrels. It is difficult to deal with, requiring a special gun and extreme care. It produced a nice finish but like many ceramics it is brittle and sometimes chipped around the bolt holes. It's also pricey. I wanted to switch to a stoving enamel that was little less expensive and hopefully tougher and easier to deal with but I wanted to make sure that I was not going to mess with the piston clearances I had been using. The heat tests have done that.
Second was I wanted to establish a method and baseline for some testing I want to do on my billet barrel and use that input to help determine what I need for piston clearance.

So now I have switched to Indestructable Coatings black stoving enamel. It is much easier to work with and has proven to be extremely tough.

PS- In the video I referred to thermotech coating. That is not actually the name of the product but a generic name to an aerospace heat dissipating coating. If a company named Thermotech makes a head dissipating coating I am not aware of it.

Here is another "boring" day in my shop.

[video]http://youtu.be/oWxjaBdaBxI[/video]

Boring jobs Jim though your practiced hand technique with extra reach bore gauge is not lost on me. Commando hospital TV series with and w/o cliff hanger episodes. Hey while ya got the temp testing set up how about checking those new bores at say ~500'F which ya know bores can reach on the boil.

Hi comnoz.
I love work. In fact, I could watch work all day - and now I can.

I decided to run some more tests at temps similar to normal operation. I made a new 5000 watt heating element and used a small PC fan to move some air.

[video]http://youtu.be/rWNs0f5Ly9k[/video]

The results after 2 hours on time were.

aerospace coatings barrel, the thinnest coating - 308 F.
powder coat barrel, the thickest coating - 281 F.
enameled barrel, 3 medium coats - 272 F.

That is over 30 degrees difference from highest to lowest.....

Using my infrared temp sensor on the rear of the barrels -out of the direct airflow -I observed temperatures between 410 and 425 F.
That is where the barrel temp sensor on my bike is located and is around the normal temps I see at highway speed. [with the aerospace coating]

At that temp I could scratch the powdercoat with my fingernail. Jim

based on your new test are we to assume that the lower temperature is more desirable?

Dennis

Dennis C said:

based on your new test are we to assume that the lower temperature is more desirable?

Dennis

Click to expand...

Sure,
the higher the temp the faster they wear and the higher the fuel octane requirement. Jim

There is one more test I want to do. I am going to strip the aerospace coated barrel and give it an enamel coating -just to make sure there is not some other anomaly with the barrel that is causing the high reading. Jim

Comnoz this confused me on how to interpret this last test. Personally- I'd pick the finish that allows highest infrared temp to show up on outside, ie: closest to internal temperature being expelled, Except if it was my thermos of coffee. So is it really better to see cooler outside temps in this test? Would need to know the internal temp to decide which finish ran cooler internally.

peter12 said:

Havn't read all the comments but a great experiment with an interesting result.
Sure this has been discussed many times but is there a real issue with the temp these motors run at.
I had my 850 motor in a reasonable state of tune in 1976, one of the hottest UK summers.
I thrashed it around all summer, fitted a T150 oil cooler w/out a thermostat only to find that the general consensus was that my motor was running to cool.
Also I don't recall seeing any Commando motors currently within the CRMC with oil coolers.
Discus!!

Click to expand...

I can tell you that I started carrying a digital thermometer around with me and testing my oil temps. In the 50 and 60 degree weather I normally ride in, I have trouble getting my oil hot enough to work to its full potential. 145 degrees is pretty common. So, yeah, I think it is real possible to be running your bike too cool. I have not done extensive testing regarding different grades of oil. Typical philosophy is cooler temps, lower viscosity, but I have started wondering if I should just run straight 50 or 40 weight. It might actually hold its heat better. So I guess I should do some testing of my own.

Russ

hobot said:

Comnoz this confused me on how to interpret this last test. Personally- I'd pick the finish that allows highest infrared temp to show up on outside, ie: closest to internal temperature being expelled, Except if it was my thermos of coffee. So is it really better to see cooler outside temps in this test? Would need to know the internal temp to decide which finish ran cooler internally.

Click to expand...

The temps I quoted were taken the same as before -with the thermocouple in the front center bolt hole.

I only used the infrared sensor to get an approximate reading at the rear of the barrel. Infrared sensors are notoriously inaccurate when they are used on different surfaces. I only used it to show that the rear of the barrels was similar to the temp I see on my bike in that same area. Jim

OK.
So we don't want to hot and we dont want to cool...but thats a fact of life with a air cooled engine . climb up the mountain...HOT, coast down COOL!
so what magic coating will keep the temps constant? 5 degrees or plus 40 roll the dice.

ok then more confused that softened plastic coat and black paint give lowest temp middle of metal mass but that's why we pay you to set us straighter. Relieves my mind now removing some expensive coating to highlight Commando engine shapes.

john robert bould said:

OK.

so what magic coating will keep the temps constant?

Click to expand...

WATER

Actually , I am not talking about oil temp. Cylinder temp and oil temp are very different.

The cooler the cylinder bore the better. If I could keep the cylinder temp near the oil temp I would be very happy -but it's not going to happen. Jim