Why the left?

Schwany · Jan 10, 2023

SteveA said:
A comment on oil pressure and centrifuging.....

When the oil is hot enough and revs are high enough....the oil centrifuges out of the oil trap....potentially at a higher rate than the oil feed pump can pump it....when the rates of input and output are equal, the pressure is zero....but the flow is the really important issue....and this is why I would not race with an oil pressure gauge fitted....and only use one for start up testing after a rebuild.

New build is why I put an oil pressure gauge back on. Good test tool. I've had it on and off the bike 4 times over the course of ownership. I reshaped the mount and now like looking at how it is mounted more than anything else. I generally only look at it when sitting still idling and blipping the throttle, or cruising. I can't remember if it went to zero when I got the motor up to what I figured was 7400 RPM based on gearing and the speedo. I was too busy watching the road ahead and looking in my rear view for the POPO at the same time.

The oil pressure gauge plumbing detour is more than likely not that good a thing. My plumbing is all 1/8" PTFE tubing, so not that big a drain on flow up top. I usually plug the oil port to the tube and remove the gauge after a few test rides. I'll do that again eventually, but leave the gauge mounted this time, so I can admire my handy work.

Onder · Jan 10, 2023

I think sometimes we get lost between what you would do for a racer v. what you do for an ordinary street bike.
All my bikes have OP gauges and I am only a street rider.

SteveA · Jan 11, 2023

kommando said:
I was not talking holes in the con rods, I cover them up by fitting 2 bottom shells anyway as they add nothing, but the holes in the crank shaft that feed oil into the shell bearings so read again. It was answer to a statement that the lower oil flow out the timing side was due to frictional loses inside the crank as the oil moved between the 2 journals.

Indeed, my apologies.

concours · Jan 11, 2023

KiwiShane said:
IMO the legalization of mind altering drugs such as you have mentioned compromises the mind development of our young and believe it eventually dumbs down the younger population that use it...who I believe end up with a lack of ambition and critical/ logical thought.
A attribute alot of the younger generation seem to have these days.
No wonder they call Marijuana "Dope"

Also, with NO WAY TO QUANTIFY THC levels, it's like legalizing drunk driving.
One beer, or 25..... doesn't affect ya... yeah, right.

I discount the oil flow difference to the ROD bearings theory. The large chamber from which they both are fed is my reason why.

Torontonian · Jan 11, 2023

concours said:
Also, with NO WAY TO QUANTIFY THC levels, it's like legalizing drunk driving.
One beer, or 25..... doesn't affect ya... yeah, right.

I discount the oil flow difference to the ROD bearings theory. The large chamber from which they both are fed is my reason why.

Quantifying ( THC use levels ) , is still a recent challenge to the Police forces here in Canada .
Your license can be pulled immediately for ANY reason by the police . That includes distracted , screens , cel. phone use , talking with passengers , eating , etc.
Driving is a privilege , not a right .
BTW , Alcohol still remains the most dangerous drug on the planet .

I'm going to study a spare head I have ( this evening ) and see if a cross channel can be carved or drilled out to equalize any oil flows re : unequal pooling sides . Just for fun . Enjoy .

concours · Jan 12, 2023

Torontonian said:
Quantifying ( THC use levels ) , is still a recent challenge to the Police forces here in Canada .
Your license can be pulled immediately for ANY reason by the police . That includes distracted , screens , cel. phone use , talking with passengers , eating , etc.
Driving is a privilege , not a right .
BTW , Alcohol still remains the most dangerous drug on the planet .

I'm going to study a spare head I have ( this evening ) and see if a cross channel can be carved or drilled out to equalize any oil flows re : unequal pooling sides . Just for fun . Enjoy .

I am very much aware. Both my Grandparents were Canadian born.
I work in/around Toronto frequently.

"Your license can be pulled immediately for ANY reason by the police"
If a citizen isn't chilled to the bone by the SUBJECTIVE, and corrupt overreach afforded by this statement, (completely editing due process out of the equation) then they have already been conditioned to be a SUBJECT.

Is your spare head a usable one? Or damaged beyond repair?

Schwany · Jan 12, 2023

Easy to create the channel between the two spring pockets with a dremel or die grinder, but not a good solution. Do what Nigel did or had done on a large intake port Full Auto head.

I tried to link to the image in a post where there is some discussion or at least a couple of pictures of the modification, but it returns an error and deletes the text in this message box. Not going to try that again.

Page 6 in the post with this title

920 engine build waffle (2016)

Personally, I don't think it is much of a problem on a street bike with mostly stock parts.

baz · Jan 12, 2023

Schwany said:
Easy to create the channel between the two spring pockets with a dremel or die grinder, but not a good solution. Do what Nigel did or had done on a large intake port Full Auto head.

I tried to link to the image in a post where there is some discussion or at least a couple of pictures of the modification, but it returns an error and deletes the text in this message box. Not going to try that again.

Page 6 in the post with this title

920 engine build waffle (2016)
Personally, I don't think it is much of a problem on a street bike with mostly stock parts.

Years ago I did some work to the cylinder head oil drainage on my commando 750
It was so long ago I can't remember exactly what it was was!!

but I do remember setting the head up in it's forward tilting position and cutting a groove and enlarging the drain
I remember testing it in the side stand position to see that the oil didn't well up around the guides
There's no photos
And I am not pulling the head to take any

Torontonian · Jan 12, 2023

concours said:
I am very much aware. Both my Grandparents were Canadian born.
I work in/around Toronto frequently.

"Your license can be pulled immediately for ANY reason by the police"
If a citizen isn't chilled to the bone by the SUBJECTIVE, and corrupt overreach afforded by this statement, (completely editing due process out of the equation) then they have already been conditioned to be a SUBJECT.

Is your spare head a usable one? Or damaged beyond repair?

I have 2 750 heads in storage . Both have compromised exhaust port threads and could use new sleeves for reliability . I've tried to sell them at the Paris meet/swap but no takers there . I'm driving an 828 motor now .

Schwany · Jan 12, 2023

baz said:
Years ago I did some work to the cylinder head oil drainage on my commando 750
It was so long ago I can't remember exactly what it was was!! but I do remember setting the head up in it's forward tilting position and cutting a groove and enlarging the drain
I remember testing it in the side stand position to see that the oil didn't well up around the guides
There's no photos
And I am not pulling the head to take any

Misty memories.

Unless you did something with magical tools after lighting up a spliff, I think you may only need to take the intake valve cover off to see your masterful drainage work on the intake side.

By the way I was looking into that little drain hole in the spring pocket and it is kind of a miracle that oil ever gets down where it needs to go given how it was drilled and has a 90 degree turn in it. If a valve stem seal ever got hard enough to come apart into small pieces, it would block that hole, and all sorts of hell could ensue.

Mart UK · Jan 12, 2023

That's why I switched to the neoprene type gaskets on the covers. Wellseal had been used previously and dripped or was flushed by oil into the drain hole.

cliffa · Jan 12, 2023

baz said:
Years ago I did some work to the cylinder head oil drainage on my commando 750
It was so long ago I can't remember exactly what it was was!! but I do remember setting the head up in it's forward tilting position and cutting a groove and enlarging the drain
I remember testing it in the side stand position to see that the oil didn't well up around the guides
There's no photos
And I am not pulling the head to take any

Some folks have no commitment

concours · Jan 12, 2023

Mart UK said:
That's why I switched to the neoprene type gaskets on the covers. Wellseal had been used previously and dripped or was flushed by oil into the drain hole.

518 Loctite.
Anaerobic.

Fast Eddie · Jan 12, 2023

Schwany said:
Easy to create the channel between the two spring pockets with a dremel or die grinder, but not a good solution. Do what Nigel did or had done on a large intake port Full Auto head.

I tried to link to the image in a post where there is some discussion or at least a couple of pictures of the modification, but it returns an error and deletes the text in this message box. Not going to try that again.

Page 6 in the post with this title

920 engine build waffle (2016)
Personally, I don't think it is much of a problem on a street bike with mostly stock parts.

If you’re talking about the oil drain, B-Bogus already posted a pic in #50.

Schwany · Jan 13, 2023

Fast Eddie said:
If you’re talking about the oil drain, B-Bogus already posted a pic in #50.

I repeated something already mentioned in a thread. Probably the first person to ever do that on the internet. lol

I must have skimmed over the page it was mentioned on.

Carl H · Jan 14, 2023

SteveA said:
Check away, it was Peter Williams who calculated that on the mountain mile oil, pressure would drop to zero! (and shared that little gem with me in conversation in '78)

The pumps work...just....a crank spinning at over 7000rpm is a better centrifuge than you would think too!

I don't run a gauge, because at max rpm in top I really don't need the distraction of seeing a huge oil pressure drop, it would be hard to maintain concentration!! Just like you say....

.....and if yours never drops below 35psi, you should begin doubting it anyway, or just ride a bit harder!

Temp gauges are an experiment, I only used them so far on a track day, it's likely they won't be there on race day! Same logic...distraction!

My race bikes were my street bikes, and I rode hard enough to win 3 USCRA Open class Championships. The Class is for 750CC max , drum brake bikes. I only won a few races but scored points in every race, But considering I was racing against some of the countries best , Like Todd Henning #454, Jerry Wood #3, Greg Nichols#15 and the Iron Man Dave Roper and others, I figured I did ok to win the #1 plates in my class. But my odd looking Commandos did well and I got many famous HOF Riders to want to race them. So if you can get distracted by an Oil pressure gauge, You can try what YD did and like Joe Bolger quipped after the race "Yvon sure spent a lot of time looking backwards." But this was probably due to the fact that two racers had tried to out brake him in the famous Laconia "hair pin" and nearly took him out , but after a few hard laps he had such a lead over the two featherbed Nortons. ( one of them had just won the Bears Race in Daytona). That Yvon was chopping the throttle and gave them a stare down to remind them who they were up against and save unnecessary wear and tear. Which when you race in Vintage classes always make the mechanic/ sponsor happy.

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Carl H · Jan 14, 2023

Carl H said:
My race bikes were my street bikes, and I rode hard enough to win 3 USCRA Open class Championships. The Class is for 750CC max , drum brake bikes. I only won a few races but scored points in every race, But considering I was racing against some of the countries best , Like Todd Henning #454, Jerry Wood #3, Greg Nichols#15 and the Iron Man Dave Roper and others, I figured I did ok to win the #1 plates in my class. But my odd looking Commandos did well and I got many famous HOF Riders to want to race them. So if you can get distracted by an Oil pressure gauge, You can try what YD did and like Joe Bolger quipped after the race "Yvon sure spent a lot of time looking backwards." But this was probably due to the fact that two racers had tried to out brake him in the famous Laconia "hair pin" and nearly took him out , but after a few hard laps he had such a lead over the two featherbed Nortons. ( one of them had just won the Bears Race in Daytona). That Yvon was chopping the throttle and gave them a stare down to remind them who they were up against and save unnecessary wear and tear. Which when you race in Vintage classes always make the mechanic/ sponsor happy.

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Jerry Wood #3 after continually distracting the F750 Daytona winner on a Rickman 750 at Loudon by showing him a wheel in most every corner, Jerry climbed onto the tank , not so much to not see the pressure gauge, but to add pressure to the front tire so he could roll into the turns faster and save the drum brakes for the last lap pass and dash to win the Loudon AHRMA Formula 750 national. Wood said he had to work hard for that one as the bike I brought up had clip-ons and it was a handful. A big win for a streetbike against a proven F 750 winner. But as I always say " They don't call em Commandos fer nuthing." And apparently a lot of Hall of Fame members took notice and took the chance to ride a real fast Commando. I am very proud of what a bike I built did and the riders who were willing to get on board, Best of all they all finished well at Loudon and Laconia and were easy on the equipment. And I did not have to pressure them at all.

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MikeG · Jan 14, 2023

Carl H said:
Jerry Wood #3 after continually distracting the F750 Daytona winner on a Rickman 750 at Loudon by showing him a wheel in most every corner, Jerry climbed onto the tank , not so much to not see the pressure gauge, but to add pressure to the front tire so he could roll into the turns faster and save the drum brakes for the last lap pass and dash to win the Loudon AHRMA Formula 750 national. Wood said he had to work hard for that one as the bike I brought up had clip-ons and it was a handful. A big win for a streetbike against a proven F 750 winner. But as I always say " They don't call em Commandos fer nuthing." And apparently a lot of Hall of Fame members took notice and took the chance to ride a real fast Commando. I am very proud of what a bike I built did and the riders who were willing to get on board, Best of all they all finished well at Loudon and Laconia and were easy on the equipment. And I did not have to pressure them at all.

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Having seen your bikes race a few times at USCRA Loudon events all I can say is thank you for the great racing entertainment. I think Greg Nicholes is one of the smoothest riders I have ever watched.

Why the left?

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