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Message started by ThumperPaul on 07/19/24 at 15:27:08

Title: Cylinder Head Assessment Help
Post by ThumperPaul on 07/19/24 at 15:27:08

Decided to dive in and start removing the head today. Can I get some eyes on these photos and your assessments.

My notes:
1) Dry condition. Not much oil up there.
2) Looking around the exhaust springs/valley, you can see evidence of burnt oil. Running hot, low oil or oil pressure, too much idling on the side stand??
3) Aside from being rather discolored, I think the cam looks pretty good.
4) Pads on rockers look like normal wear.
5) Overall it seems like normal wear.

I'll actually pull the head tomorrow so we can see the valves and more.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/19/24 at 15:28:02

another view.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/19/24 at 15:28:52

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/19/24 at 15:30:52

exhaust side, springs, plug. Hey, the plug wasn't leaking (maybe it needs oil up there to actually leak).

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/19/24 at 15:32:01

Cam bearings (or are those journals) in the head. I mix those up.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/19/24 at 15:32:52

rocker pads and more.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/19/24 at 15:34:07

Dropping bread crumbs to get me back home.

Title: Re: Cylinder Head Assessment Help
Post by Dave on 07/19/24 at 18:17:42

Where are the traces of oil? That thing looks really dry.

So far the head looks good.

Those rockers appear to be the old style used prior to 2005 - they look a bit worn. The newer style with the brazed on pads are much more durable.

Title: Re: Cylinder Head Assessment Help
Post by DragBikeMike on 07/19/24 at 22:35:11

Paul, you need to show us the nose of the cam lobes, not the base circle.

I agree with Dave that the interior is exceptionally dry, almost as if someone cleaned it with solvent, let it dry, and then assembled it. Only way to tell for sure is to disassemble it and measure everything. I don't see any showstoppers at this stage. The shellac in the exhaust pocket is difficult to assess; it gets pretty hot in that location. The only LS650 heads I have worked on that had coking in that area were melt downs, but that doesn't mean that any evidence of coking is bad. It might be just normal deposits. I wouldn't worry about it if the head checks out dimensionally. Visually it looks pretty good.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/20/24 at 04:19:36

Thanks guys!

Dave, you’re right. It is a 2000 model year. They are probably the original rockers.

Mike, the photos are after I cleaned up the mating surfaces and I probably did wipe some brake parts cleaner in the whole area. But it was dry when I opened it up.

I’m going to plow ahead with disassembly today. I also need to take a pic of what I can’t tell are “hairline cracks” or imperfections in the casting mold (or both).

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/20/24 at 05:39:43

A pic of either hairline cracks or imperfections in the casting. Using the pick to point out the area only. I can feel it with my finger, but I can’t tell if it’s just how it was cast or if they are cracks. If they are cracks, they seem superficial, but I’m far from an expert.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/20/24 at 05:43:23

The outside looks fine.

Title: Re: Cylinder Head Assessment Help
Post by Fast 650 on 07/20/24 at 06:26:58

That looks like it is just casting marks to me.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/20/24 at 07:03:48

Thanks Fast650! I like that answer!

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/20/24 at 07:05:08

Glad I found some black gold in the well!

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/20/24 at 07:07:53

A more thorough inspection and some measuring is needed, but the cam looks pretty good. Clean sharp edges and no scaring on the lobes.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/20/24 at 07:55:22

The other ones were tough, but this guy is an A-Hole! Can’t get a socket or box end on it. And now I’ve rounded it off with an open-end wrench. Vise grips are slipping too! Argh!

Title: Re: Cylinder Head Assessment Help
Post by Graybeard on 07/20/24 at 07:56:21

The cavity below the lumps on the cam should have oil in it.
Your diagram for bolts? It would be great if others could print that.
That is Noice!
Don't forget to drop the middle bolt in before it gets set in place.
IIRC there is a corner bolt that goes in the jug and up through the head,,right?
As dry as that is I'm surprised stuff doesn't look galled and scorched.

I'm wondering if you shouldn't give the oil pump a test.
YaKnow, the drive gear for it goes in wackberds and Looks like it's just Fiiine.. ButitAin't..
Have you been in the clutch recently?

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/20/24 at 08:03:37

So while stewing on how to remove the A-Hole nut, I decided to remove the rear cam chain adjuster/guide. I’ve decided that the bigger your banana, the more you need a Versy CCT. I could have waited until I pulled the head to remove the guide (easier), but I felt like fighting the guide out. I’ve also decided that the bigger your banana bend, the harder it is to get the sucker out!

Aside from being a bit banana-shaped, the thing looks brand new.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/20/24 at 08:22:25

665340584344405345210 wrote:

Yes, at least there was some oil in the cavity below the cam lobes. As dry as everything else was, this was a relief.

I found that bolt diagram here on the forum somewhere. Then took it to the copy place and enlarged it onto like 14x17” paper. Then taped it to a piece of cardboard box.

If I was working with the motor in the frame, then yes “B70” needs to be in place on the head cover before you slide the head cover under the frame and onto the head.

I don’t know what IIRC is, but “B65 bolt” does need to get trapped in its spot before you put the head cover on. I’ve got it positioned upside down in my diagram (the other side should have a pretty cap nut, but this one just has a regular nut).

Clutch pack will get inspected next. I want to get this head off right now. darn A-Hole nut!

Title: Re: Cylinder Head Assessment Help
Post by Michael Moore on 07/20/24 at 22:25:13

IIRC = If I Remember Correctly

Title: Re: Cylinder Head Assessment Help
Post by Dave on 07/21/24 at 03:31:32

That stubborn nut should only be attempted with a box end wrench - as you can tell an open end wrench will just round things off.

I would be tempted to try a couple of things - not sure which would work better:

You could try using a chisel on the side of the nut that will move it in the direction it needs to go to be loosened. This is a bit brutal - but it has worked for me in the past.

Another option is to screw a nut on the few threads that are remaining - then weld the new nut to the existing nut. One potential problem in doing this is if you have enough room to get a box end wrench on the new nut when you do this. Also.....if the stud comes out of the head rather than the nut coming loose - now you have a stud and welded double nut stuck in the head. The potential good news is that if you are able to put the wrench on the nut while it is still hot - it likely will come loose easier.

Are you starting to realize that working on old motorcycles is not all that relaxing? :-?

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/21/24 at 04:47:47

Thanks Michael and Dave.

IIRC - I never remember correctly according to my wife!

Dave - You nailed it with the relaxing hobby comment! All 4 of the Savages/S40s I’ve bought and owned were with the intent of keeping for myself once I got them running well and given some TLC. It is rewarding and kinda fun bringing them back to life and made truly road worthy again. But as you know, I keep running hot/cold on how much I really like the Savage and end up selling.

This bike, Bumblebee (#5), was bought with the intent of getting some usable parts, like a head to practice porting, and then part-out the rest to cover my initial cost and maybe finance a few extra goodies. Now I’m questioning my want to play with and practice porting the head. Wanna buy it and save me some torture? Save you some torture too when I have to post about it and ask 47 questions. Lol.

Mad at myself for rounding off that nut. I knew the open end was a bad idea but it worked fine on the nut up front. The 12 point box end that I could fit in there wasn’t any better. I’m getting a new set of small 6-point 15° offset combo wrenches today. I needed some metric 6-point combo wrenches anyway. Perhaps just using the right tool will work. Add some heat and try that if I have to. It’s not a good spot to try to get penetrating oil or PB Blaster in there, but I’m trying that too.

I like the welded double-nut idea, but I don’t weld or have the equipment.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/22/24 at 15:40:02

I finally got the pesky nut off.

It has 4 valves and carbon to look at.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/22/24 at 15:41:50

Another view. Spark plug hole looks good! Lol.

I need better lighting in the garage.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/22/24 at 15:43:55

A cursory look at the piston. Most of that carbon vacuumed right off. More pics when I remove the jug in the next couple of days.

Title: Re: Cylinder Head Assessment Help
Post by Dave on 07/22/24 at 19:32:31

That looks like a lot of carbon on the top of the cylinder.....maybe it is just looking like that from sitting a while.

The weird part about carbon......is this:

If you take your bike apart soon after you last had it running. The exhaust valves and the inside of the header are light tan or nearly white. If you take an engine apart after it has sat idle for a while - the carbon on the exhaust valves and header has turned completely black. And as you have noticed - some of the carbon has become soft or flaky and loose.

Title: Re: Cylinder Head Assessment Help
Post by ohiomoto on 07/22/24 at 20:11:17

Does that bike have a 155 main jet by chance???

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/23/24 at 04:00:58

Interesting observation, Dave! Thanks. Along those lines, the carbon on the exhaust valves is less thick and more of a tannish brown color while the other areas are black.

OhioMoto - I bought this bike for parts. The carb was gone when I got it, so I have no idea about jetting. It did have a SuperTrapp muffler on it, so a prior owner probably did tinker with the carb. And the air box was cut open around the snorkel area (rather crudely butchered) presumably to accommodate a larger air filter setup.

Title: Re: Cylinder Head Assessment Help
Post by Dave on 07/23/24 at 04:14:00

3408150D1005123001150C600 wrote:

And the air box was cut open around the snorkel area (rather crudely butchered) presumably to accommodate a larger air filter setup.

I am pretty sure I have a good stock air filter box...only 1,200 miles on it!

Title: Re: Cylinder Head Assessment Help
Post by Graybeard on 07/23/24 at 04:19:30

People spend more time on exhaust flow than intake, I think. I didn't make a PHD study of it, but did come to understand one thing that I think is important. The volume of the intake between the filter and carburetor needs to be at least equal to the volume of the cylinder. More is better, but equal to is minimum for making it go good.

Yeah, Dave, interesting osbervation.

Title: Re: Cylinder Head Assessment Help
Post by Fast 650 on 07/23/24 at 06:59:35

7A4F5C445F585C4F593D0 wrote:

Tuning the intake volume and length has practically no effect with the stock cam though since it has zero valve overlap.The only thing that will have an effect with the stock cam is the distance between the filter and the carb. If you have a pod filter at the carb the air has to make a sharp turn to enter the carb and that causes turbulence. Moving that pod filter farther from the carb inlet gives the air time to straighten out and the flow will be better then.

Drop in a hotter cam with some overlap and then you can tune the intake and exhaust to take advantage of the scavenging effect.

Title: Re: Cylinder Head Assessment Help
Post by Graybeard on 07/23/24 at 10:34:04

One of the things that was in the article was an analogy with the
Fat straw versus skinny straw. If enough air is between the filter and carburetor so the cylinder can be charged without having to drag it through the filter, it gets a more complete charge. Intake relies entirely on atmospheric pressure to push air in, because of the vacuum from the piston falling. Exhaust has the piston shoving it.
I wish I could reference the article. That's all I've got,man..

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/23/24 at 14:29:16

You guys, please carry on about how engines suck and blow.

In defense of a UNI pod filter connected directly to the carb, the filter does have a back end too where air can come in and mix with the curvy air coming in from all sides. My 5" UNI filter butts right up to the opening in the air box where the snorkel (turbo tube) used to live. I have the stock air filter removed and side air box cover removed so I know the UNI is sucking at least some straight air through there. How much straight air vs curvy turbulent air is getting sucked is unknown. Only the air horn side of the carb knows and it ain't talking, but it’s trying really hard to get the air straightened out before it runs into gasoline. And the “air striker” on the PWK carb is also trying to get the air moving nicely I do like the "induction" sound of the UNI connected directly to the carb.

Ok, here's a piston to look at....

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/23/24 at 14:30:50

Underside. All good.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/23/24 at 14:34:22

The cylinder bore is really nice. I haven't done any precision measurements, but the cross-hatching is still visible and looks good. No stratches, gouges, or weird stains.

Hard to get good photos of the bore. The endoscopic camera isn't any better - too many reflections. I may try it again to get better photos.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/23/24 at 14:36:52

another less than ideal photo.

Title: Re: Cylinder Head Assessment Help
Post by Dave on 07/23/24 at 19:16:00

Looks like the second ring got a bit of corrosion going on......and the cylinder looks like it may have a matching line of corrosion as well.

Or......maybe the photos and my eyes are not seeing things! It is very hard to take good photos of shiny things!

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/24/24 at 05:52:12

Thanks for taking a look, Dave. The 2nd ring is more like gunk than corrosion.

At the top of the cylinder wall, I believe that’s the “carbon ring” that Clymer and others say not to remove or you risk excessive oil consumption. I could use some educating on that…

I like things clean. To me, all gunk is bad. I want to clean it so bad. But, I guess gunk in the right places acts as a sealant (keeps the oil out of the combustion chamber).

New motor = no gunk, no carbon, get the rings to seat during the break-in period and let the fresh carbon build-up do its sealing job…. Right??..

Rebuilt motor with fresh cylinder bore/hone and a new piston …. Same thing…

Disassemble, Inspect, no rebuild, reassemble…. If you clean off the carbon ring, won’t it just make a fresh mess in 300-400 miles? You’d want to take it easy anyway and give it something of a break-in period just like a new motor or rebuild…

I’m really struggling with why you shouldn’t clean up the old carbon mess. Again, I like clean…. I suppose if I think about it and answer my own question….it has to do with new parts having super tight clearances while used parts are rather worn in. Too bad it doesn’t work like washing a t-shirt and comes out of the dryer a little snug and you have to wear it a few days in a row to make it comfortable and broken in. ;D :o
;)

Title: Re: Cylinder Head Assessment Help
Post by Dave on 07/24/24 at 07:14:55

I remove the ring of carbon that is above the piston - that stuff can come loose and score the piston/cylinder.

I take a sharp razor blade and run the side I am going to be using across some sandpaper to remove any burs on that side....then at the same angle I carefully scrape while holding the razor blade as parallel to the cylinder as I can get.

And since you are going to hone the cylinder to make a cross hatch for the new rings to seat on.......you need to have that carbon gone or it will mess up the hone.

Maybe I could interest you in a nice 95mm Wiseco piston and cylinder?????? ::)

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/24/24 at 12:46:44

Thanks Dave! Appreciate you sharing your thoughts and method. I’ll trade ya! Lol.

Seriously though, I’ve come to the decision to leave “Blue” mostly stock and sell these parts bike parts. I’ll sell ‘em “reasonably cheap” and hopefully someone with more skill and desire can have some fun with them.

Speaking of over-bores…the cylinder wall already seems thin. Do people really bore this stock cylinder to 97mm? Seems like that is getting dangerously thin for the cylinder wall. Or is there a 97mm sleeve available and a lot of other machine work done to the cylinder to accommodate a larger sleeve?

Title: Re: Cylinder Head Assessment Help
Post by Dave on 07/24/24 at 13:55:10

The 97mm bore does leave a thin cylinder wall. DragBikeMike has commented on the issue and how flimsy the cylinder wall likely is.

However - the 97mm pistons do work well and there are a lot of them out there doing their job just fine.

Title: Re: Cylinder Head Assessment Help
Post by DragBikeMike on 07/26/24 at 17:12:08

Looks to me like that motor had a steady diet of dirt. Those striations above the top ring look like there was all sorts of abrasive material in between the piston and cylinder.

I agree with Dave, the second ring looks like it has a lot of corrosion. If it were simply "gunk", you would see it on the oil rails (oil control ring) and the top ring (compression ring). The compression ring is stainless steel with a plasma coating. The oil rails are also stainless steel and probably have a plasma coating. The second ring (oil scraper ring) is cast iron. It corrodes easily. It was probably sitting in one location for a very long time. If there is pitting in the cylinder it will be easy to see when you kiss it with the hone.

Note how the entire surface of the oil scraper ring (2nd) is polished, top to bottom. When the oil scraper is in good condition, only the bottom half will be polished. That's because the scraper has a trapezoidal cross section. The trapezoid forms a sharp edge at the bottom of the ring. That sharp edge allows the scraper to wipe the oil off the cylinder as the piston moves down. It is easy to install that ring upside down. When you make that mistake, it becomes an "oil pumper" instead of an "oil scraper".

Title: Re: Cylinder Head Assessment Help
Post by DragBikeMike on 07/26/24 at 17:13:38

This shows a typical oil scraper. Note how the top half of the ring is black, while the bottom half is polished.

Title: Re: Cylinder Head Assessment Help
Post by ThumperPaul on 07/27/24 at 04:12:26

Thanks Mike! I sincerely appreciate you taking the time to provide an assessment and give me a good basic education on how to evaluate piston rings.

So, sitting around doing nothing for a good while is probably the main cause of corrosion on the oil scrapper ring (2nd compression ring)? Did I understand that correctly?

With the 2nd ring as is, how would engine performance likely be impacted? Would excess oil consumption be likely?

Regarding the gunk (I’m still thinking carbon) at the top of the cylinder wall above the compression ring, what are you seeing to suggest filthy air/fuel mixture?

Interested in your thoughts. Thanks!