Crankshaft bearing shields: an option?

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Tomcatfixer
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Re: Crankshaft bearing shields: an option?

Post by Tomcatfixer » Sat Apr 11, 2020 6:08 pm

BillyG wrote:
Sat Apr 11, 2020 5:57 pm
You don't need to notch anything. Pull one shield and leave the other alone. I did this on both crank bearings 150-200K km's ago. I don't hurt sh#t.
Well, you ARE Dr. Billy G, creator of the helpful MyUral site, so your opinion carries much weight, but I have to ask: in all of those kilometers, did your rig experience any rear main seal leaks?
- Chad

Gordonsville, Virginia, USA

Current rides:
2015 Ural cT "Mobile Chernobyl", 2001 Ural Patrol "Little Red Bear", 1999 Ural Tourist "The RPOC", Mid-Nineties Ural Tourist "The Heap", 1994 Honda VFR750F

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2007 Honda VTR1000 FireStorm (Super Hawk in U.S.)
2001 Buell Blast! - - - - - - - 2005 Yamaha FJR1300
1993 Honda CBR600F2 - -1984 Yamaha FJ1100
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Re: Crankshaft bearing shields: an option?

Post by BillyG » Sat Apr 11, 2020 8:48 pm

No. Dry as a bone. Shields and seals don’t stop oil from passing/weeping through the bearing. Seals are mainly for keeping dirt out and grease in place. If the bearings and seals are not Russian...the leak is probably due to crank or other alignment/tolerance issues.
Bill Glaser
2002 Ural Patrol "CYKA"
300,000 km's since May 1st 2002
The "Unofficial Ural Service Manual" can be viewed at: http://www.myural.com

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Re: Crankshaft bearing shields: an option?

Post by Snakeoil » Sat Apr 11, 2020 9:00 pm

The slinger I was talking about is not the slingers that feed the big ends. The slinger was between the bearing and the seal. It was a separate piece that slips on the crank. I think Terry said it was used on late 650s.
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Rob
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Re: Crankshaft bearing shields: an option?

Post by Tomcatfixer » Sun Apr 12, 2020 6:45 am

Snakeoil wrote:
Sat Apr 11, 2020 9:00 pm
The slinger I was talking about is not the slingers that feed the big ends. The slinger was between the bearing and the seal. It was a separate piece that slips on the crank. I think Terry said it was used on late 650s.
My '99 had nothing of the sort. When I open my '01, I'll look for such a contraption.
- Chad

Gordonsville, Virginia, USA

Current rides:
2015 Ural cT "Mobile Chernobyl", 2001 Ural Patrol "Little Red Bear", 1999 Ural Tourist "The RPOC", Mid-Nineties Ural Tourist "The Heap", 1994 Honda VFR750F

Previous rides:
2007 Honda VTR1000 FireStorm (Super Hawk in U.S.)
2001 Buell Blast! - - - - - - - 2005 Yamaha FJR1300
1993 Honda CBR600F2 - -1984 Yamaha FJ1100
Two different 1986 Yamaha FZX700S Fazers

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Re: Crankshaft bearing shields: an option?

Post by Snakeoil » Sun Apr 12, 2020 10:50 am

If I'm out in the shop today, I'll see if I can find the one that came out of my engine.
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Rob
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Re: Crankshaft bearing shields: an option?

Post by jaybird » Sun Apr 12, 2020 10:57 am

Tomcatfixer wrote:
Sun Apr 12, 2020 6:45 am
Snakeoil wrote:
Sat Apr 11, 2020 9:00 pm
The slinger I was talking about is not the slingers that feed the big ends. The slinger was between the bearing and the seal. It was a separate piece that slips on the crank. I think Terry said it was used on late 650s.
My '99 had nothing of the sort. When I open my '01, I'll look for such a contraption.
I’ve see/encountered the disk that Rob describes.
I tried to find a clear illustration of it in my books or something I could get to on a parts engine, no luck though.
I’m sure there are photos of that disc buried in the forum from back in the day when the 650 was more common and breaking on a regular basis.
I don’t think it’s worth the time to go looking for it.
I’m in favor of leaving an un notched shield on the flywheel side as I think enough oil will naturally get over there to lubricate the seal.
More importantly, I believe that the shield on the flywheel side and none on the crankshaft side will help to force more oil into the slinger/rod bearings were it’s needed more.

Happy trails,
Jaybird
2005 Gear-Up, Mr. Nat_ural 108,000+ Kilometers and counting
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Re: Crankshaft bearing shields: an option?

Post by Tomcatfixer » Sun Apr 12, 2020 10:59 am

I might have misspoke. I took a peek at the my three 650 engines that still have crankshafts installed and this is what I found:

2020-04-12 10.55.57.jpg
2020-04-12 10.56.19.jpg
2020-04-12 10.56.39.jpg
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- Chad

Gordonsville, Virginia, USA

Current rides:
2015 Ural cT "Mobile Chernobyl", 2001 Ural Patrol "Little Red Bear", 1999 Ural Tourist "The RPOC", Mid-Nineties Ural Tourist "The Heap", 1994 Honda VFR750F

Previous rides:
2007 Honda VTR1000 FireStorm (Super Hawk in U.S.)
2001 Buell Blast! - - - - - - - 2005 Yamaha FJR1300
1993 Honda CBR600F2 - -1984 Yamaha FJ1100
Two different 1986 Yamaha FZX700S Fazers

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Re: Crankshaft bearing shields: an option?

Post by Tomcatfixer » Sun Apr 12, 2020 11:01 am

More importantly, I believe that the shield on the flywheel side and none on the crankshaft side will help to force more oil into the slinger/rod bearings were it’s needed more.
That's an interesting hypothesis. Seems reasonable.
- Chad

Gordonsville, Virginia, USA

Current rides:
2015 Ural cT "Mobile Chernobyl", 2001 Ural Patrol "Little Red Bear", 1999 Ural Tourist "The RPOC", Mid-Nineties Ural Tourist "The Heap", 1994 Honda VFR750F

Previous rides:
2007 Honda VTR1000 FireStorm (Super Hawk in U.S.)
2001 Buell Blast! - - - - - - - 2005 Yamaha FJR1300
1993 Honda CBR600F2 - -1984 Yamaha FJ1100
Two different 1986 Yamaha FZX700S Fazers

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Re: Crankshaft bearing shields: an option?

Post by rougaroo » Sun Apr 12, 2020 11:41 am

Interesting. There's often a thing called a wiper found on shafts for parts that go in-and-out like telescoping forks (as opposed to round-and-round, like the crank). The wiper "wipes" the shaft ahead of the seal and keeps crud from riding on the shaft through the seal, wearing out the seal faster and contaminating the oil. Even though the crank is only rotating, I can see a wiper performing the same function here, especially when you consider how dirty the bell housing gets with dirt, clutch dust and such.

Here's a reference on oil wipers: https://www.cookcompression.com/product ... r-packing/

To me it seems like one of those "can't hurt - might help" things.

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Re: Crankshaft bearing shields: an option?

Post by RC20 » Sun Apr 12, 2020 2:48 pm

Observation from some hundreds of bearing replacements (electric motors, generator and fire pumps).

SKF are by far the best. Never had a bad one. Fafnir was as good at one time but Timken bought them out and went to low cost market produion (cheap). If I was doing an engine I would get all SKF even if I had to order them. Bearing houses will have most of those in stock.

Sans other info, I would take and leave the shields off (or get them without shields). One of those it might not make any difference but its not going to hurt anything. Seals need oil to work right, seems from BillyG its not an issue.

We may be looking at a situation where a Russian seal needs more lube than a higher quality replacement seal ergo the setup for more flow and slinging.

Now if you really want to get an easy spinning engine, go with Ceramic Hybrid (SKF or Koyo makes them though I would go with SKF as had lower cost Koyo that screamed). Sticker shock though. Those are amazing for zero friction (long boring story as to why I had to use them). Bottom line is normally with a greased bearing you could tell on an electric motor the bearing were well into their service life by how long it took to wind down (faster newer, if they ran on and on they were about done). Ceramics new spin like they had 100,000 hours on them.
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Re: Crankshaft bearing shields: an option?

Post by Tomcatfixer » Sun Apr 12, 2020 3:00 pm

You can tell from my second image that I have already selected and purchased quality SKF and Koyo bearings.
- Chad

Gordonsville, Virginia, USA

Current rides:
2015 Ural cT "Mobile Chernobyl", 2001 Ural Patrol "Little Red Bear", 1999 Ural Tourist "The RPOC", Mid-Nineties Ural Tourist "The Heap", 1994 Honda VFR750F

Previous rides:
2007 Honda VTR1000 FireStorm (Super Hawk in U.S.)
2001 Buell Blast! - - - - - - - 2005 Yamaha FJR1300
1993 Honda CBR600F2 - -1984 Yamaha FJ1100
Two different 1986 Yamaha FZX700S Fazers

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Re: Crankshaft bearing shields: an option?

Post by RC20 » Sun Apr 12, 2020 5:32 pm

Tomcatfixer wrote:
Sun Apr 12, 2020 3:00 pm
You can tell from my second image that I have already selected and purchased quality SKF and Koyo bearings.
Noted, we only used the one Koyo and their reputation is good (Toyota bearing mfg division ?)
Fear No Gravel
Formerly Owned: ( various rides on others)
Honda 90
2 x CB750K (one a true Japan Model flown to Hawaii by a P3 Orion Sub Patrol Aircraft!)
1 x CB700 SC ala Shaft Drive Nighthawk S (RC20 is the actual in house production Model)
1 x R80GS (ok to start with, learned to love it for what it was)
1 x CB450K

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1 x 2019 cT Terracotta

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Re: Crankshaft bearing shields: an option?

Post by Snakeoil » Mon Apr 13, 2020 12:16 pm

Yup, that's it. Guess I don't have to dig thru my old parts box now.

I suspect what it does is help stop oil from pooling between the seal and the back of the bearing, and encourages the oil to leave via the drain ports at the bottom of the bearing bore. The snout of the flywheel keeps it close to the bearing.
Regards,
Rob
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Re: Crankshaft bearing shields: an option?

Post by URALNUT60 » Wed Apr 15, 2020 8:34 pm

Question the blue grease on the bearing with shields, okay to leave it w@$# away eventually or remove with mineral spirits and oil?

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Re: Crankshaft bearing shields: an option?

Post by jaybird » Wed Apr 15, 2020 8:43 pm

URALNUT60 wrote:
Wed Apr 15, 2020 8:34 pm
Question the blue grease on the bearing with shields, okay to leave it w@$# away eventually or remove with mineral spirits and oil?
I leave it.

Happy trails,
Jaybird
2005 Gear-Up, Mr. Nat_ural 108,000+ Kilometers and counting
2013 Retro, Black beauty, AKA Lucky "13"
1995 Olive Tourist
1975 Enfield Diesel Bullet
2008 Enfield Bullet 500
1974 BMW R 75/6
Etc.

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