How much grease should be visible on contact surfaces of bevel gears

[moribundman]

This is about my bicycle, but since it's more about gears and grease than about bicyles, I'm posting here.

I'm wondering how much grease should remain between gear teeth and on the contact areas of these shaft drive bevel gears:

(no grease)

The grease that was originally on those gears was a dark grey and rather sticky ("thready" between fingers) grease. Ironically, the recommended grease was "non-sticky" wheel bearing grease. Go figure.

I replaced the grease with AMSOIL 2000 Racing Grease #2&2EP GC LB. With the AMSOIL grease the gears run with less resistance, but I'm worried that there is not enough lubricant on the gears.

It appears that almost all grease gets squeezed out between the teeth and collects around the outer edge of the gears. Where the teeth mesh and contact (concave side of hub gear -- not really visible in the above picture!), I do not see any grease.

Can I assume that a sufficient amount of oil from the grease is present on the contact areas, or should there any grease be "stuck"? Would a lack of lubrication result in abnormal noise or be noticeable somehow before abnormal wear occurs?

 

[Kestas]

I'm curious how the grease is supposed to flow or get churned in this application.

Wouldn't a #1 grease be more appropriate? You'd want the grease to flow into the areas where it's needed. Perhaps the horizontal jostling during bike riding moves the grease around, and lighter grease would move better.

 

[crashz]

The oil in the grease is what lubricates the surfaces. The sticky soap just gives the oil a medium to work in. Otherwise the oil would run off.

Since their is no sump or packing cavity to you gear case, a heavy grease like wheel bearing grease would be appropriate. A flowing grease would flow right off of the gears when warm.

OT - but I've never seen a shaft drive bike. Love to see more pics!

 

[Papa Bear]

Mori, is there a cover for that crown & pinion set-up ?? How often are you supposed to change the grease ??
What kind of a bike is this ?? Looks like it needs a 200cc engine on it ??!!

P.B.

 

[moribundman]

The gears are normally covered. I only pulled the cover off to show the internals.

Depending on use, the gears should be regreased between every 6 months and once a year.

The bike vendor/shop says they use Polylube 1000 (urea-based with extremely high shear strength), but they also say any wheel bearing grease will be fine.

 

[bruce381]

crashz is right the grease soap holds the oil which does the lubricating if the grease stays on the gear the oil will bleed and that may/should be enough to lube the gears.
bruce

 

[Papa Bear]

When I worked at the service station in '59-'60, the mechanic used what he called "long fiber" bearing grease. I remember putting it between my thumb and forefinger and when I opened my fingers, the grease would form a "bridge" between the two. In a bearing it was always pulling itself back into the bearing.
Maybe you need some of that stuff.
P.B.

 

[Papa Bear]

""www.militec.com A friend of mine in the military turned me on to this and it is the best grease I have used! They pack all of the amphibious landing craft wheels with it...IE saltwater and sand! I have a 38 on a triple axle eagle trailer and it stopped all of my problems, I have no more heat issues or bearing failure. It does not wash out and it has a metal conditioner it. It is as stringy as chewing gum. It is by far the best grease I have ever used now matter how much it cost...synthetic or not. This Co. could make a fortune if they marketed this stuff to the marine market. This grease is DA BOMB!!""

Mori, I copied this from a thread where they were talking about repacking boat trailer bearings.

P.B.

 

[moribundman]

quote:

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if the grease stays on the gear the oil will bleed

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That's the one million dollar question! It "looks" like the contact surfaces on the teeth are running dry. But I don't know what's going on during operation. I hear no weird squeaky noises or anything!

quote:

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It is as stringy as chewing gum.

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P.B, I still have to pedal that bike!

I, of all people! don't want to go thicker than I absolutely must.

Water and sand contamination is pretty much no problem. I've ridden this bike on the beach and the gearbox is well enough sealed, even in moist, windy conditions. It's because of where I ride this bike that I didn't want to put up with a chain, chainrings and a cassette.

I went to a local bike shope and the tech said he'd use 'Finish Line Synthetic Grease' ($8 for 3.5 oz). It contains Teflon and is rated GB.It seems a lot stickier than AMSOIL.

I also found a tub of Moly Grease I bought maybe 5 years ago. It's dark gray, pretty sticky and seems totally unaffected by its age. It's made by Pacific Lubricants and it's suitable even for marine use. Also for CV joints. Anybody know this stuff?

 

[Papa Bear]

I don't know, Mori, I'd be givin' that 200cc motor a lot of thought.

P.B.

 

[brian fix]

Schaeffers 238 NLGI 0 would work,will be hard to get in just a tube,,or maybe Amsoil general purpose lithium complex in a 1 grade or so,Park tool makes a white teflon wheel bearing grease that also may be fine,BL

 

[XS650]

I packed a bevel gear housing in my chop saw with M1 grease. It seems to turn easy with the M1.

 

[tom slick]

I would give the gears a good thick coating and assemble it. the gears are going to push out the majority of it.

 

[moribundman]

Well, the gears did not push out the grease that used to be on them. But it seemed to thick...

Pablo thought the Series 2000 Series would be good, and that's why I got that. As I said, I don't notice anything weird or unusual, but I find the lack of grease on the contact areas a bit unsettling.

I guess there is only one way to find out what seems to work best: try all the dang greases I have.

Any opinion on the moly grease I mentioned? Or is that a problem with chromoly steel gears?

 

[XS650]

quote:

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Originally posted by moribundman:


I guess there is only one way to find out what seems to work best: try all the dang greases I have.

Any opinion on the moly grease I mentioned? Or is that a problem with chromoly steel gears?

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As long as a bit of the oil in the grease gets on the gear teeth, you're OK. Moly won't hurt, might help.

 

[moribundman]

Again, the grease that came on those parts from the factory was very thick and what I would call tacky. It pretty much filled the spaces between the gear teeth and didn't get squeezed out.

 

[moribundman]

Alright, I cleaned, relubed, regreased and then went ten miles with lube A. Then I checked the gears. Repeat with lube B and lube C. Turns out Amsoil does appear to stick the best, so I'm sticking with it. The Finish Line lube gets really runny and the moly grease doesn't seem to stick any better than the AMSOIL Racing grease. The gears get warm to the touch.

Jeez, my legs hurt and I think I may have torn something in my lower back.

 

[Pablo]

Didn't see this thread until today

Classic reason they use closed boxes full of gear oil. This is a tough application for a grease. After seeing the picts and digging a bit I have some more ideas, but I don't want to just have mori spend money to throw possible solutions at the problem.

Interestingly this Amsoil Syn Fifth Wheel and Open Gear grease may work - it's tacky yet much lighter than other open gear lubes. The suck thing is, it only comes in a spray can and mori needs to nipple feed it in.

I think mori is doin' some research as we speak. He's a sharp cookie.

 

[moribundman]

Sharp cookie, eh? More like a dull blade. I know almost nothing about grease, though I'm beginning to pick up some basic knowledge. I'm sorry to waste Pablo's time with all my questions, but I don't want to keep stocking up on grease that won't work perfectly.

I tried regular Plastilube and it seems to stick fine. It doesn't drip, and it doesn't get thrown off the gears. In fact, it seems pretty much ideal for my application -- at least in terms of how it adheres without being as sticky as an open gear grease. Unfortunately, I am unable to find out what type grease (multipurpose -- doh!) Plastilube is and what type additives it contains. Does it contain any EP additives? The MSDS says it's a highly refined mineral oil based grease that does not contain toxic heavy metals. Supposedly there is aso a Plastilube EP Moly3 grease that I have never seen. If anyone has any info on Plastilube beyond that, I'd appreciate if you were to share your knowledge. I have a lot of that stuff (I use it on my car's door and pedal hinges).

 

[moribundman]

This pretty much the most comprehensive info on Plastilube that I could find:

ATE plastilube® The heavy-duty, long lasting lubricant to prevent screeching disc and drum brakes.

Plastilube ® is a registered trademark of Henkel KG ATE plastilube® Continental Teves AG & Co. oHG

ATE plastilube ® The heavy-duty, long lasting lubricant that prevents screeching disc and drum brakes. ATE plastilube® makes assembling and dismantling brakes child's play. It guarantees excellent processing stability for long lasting lubrication and is ideally suited to ABS systems. ATE plastilube ® is a heavy-duty lubricant that is not only highly effective with brakes, but can also be used for bearings, chains, gears, seat runners, hinges, sunroof guides and battery terminals.

Thanks to its good pH stability, ATE plastilube is resistant to weak alkalis and acids and is not corrosive. The synthetic thickener of ATE plastilube® is so stable that the lubricant does not ouse out from the interfaces to be lubricated when sudden impacts occur or extreme pressures arise. This lengthens lubricating intervals considerably while at the same time reducing maintenance frequency.

What's more, ATE plastilube ® is water-insoluble and enjoys excellent washout resistance properties. To guarantee the temperature resistance of the lubricant, the material to be lubricated must be cleaned of all soapy lubricants.
ATE plastilube ® can be easily wiped off with a cloth or piece of fleece.
Residue can be removed with a solvent.


The Facts

• Metal-soap- and fatty-acid-free and therefore non-corrosive
• Increased lubrication intervals and reduced maintenance frequencies thanks to excellent fluidity
• Water-insoluble and with excellent washout resistance
• Versatile; compatible with all metals and most O-ring materials

Frost-proof yes
Recommended
storage temperature 10°C to 20°C
Storage period 24 months