Rear main bearing

Are ya having a problem with your rig? We'll try to help. Share your tech tips and experiences here. Dr. Billy Glaser, author of the "Unofficial 750 Ural Service Manual" site myural.com, is moderating this section.
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Fredrikrosen
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Rear main bearing

Post by Fredrikrosen » Thu May 14, 2020 5:21 pm

Hello all.

When i changed the engine oil today on my 2010 Retro did i find a piece of metal on the oil plugs magnet. It is not from a gear, more like from a ball cage in a bearing. The oil had no visible contaminations and i could not find any other pieces of metal in the oil, i will remove the sump tomorrow and will see if there is more inside. I had no choice but to disassemble the engine, i suspect the rear main bearing. Front main bearing look ok and same with the cam shaft bearings. I wonder if there is any better option than a ball bearing, might a roller bearing be a better and stronger choice?

Regards,
Fredrik
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Ural 750 Retro -2010
Ural Voyage 720 -1999
Ural 650 Solo Export -1992 :sold
IZH Jupiter-3 -1980
IZH Planeta-5 -1992
Honda CR500R -1984
Dnepr MT16 with BMW engine :sold
Dnepr K650 -1969 :sold
Ural 650 -1993 :sold

Plus another 50+ bikes though the years.

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Claus
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Re: Rear main bearing

Post by Claus » Fri May 15, 2020 3:15 am

It could be a part of a bearing, but it looks a bit large for that. it might be a part of an oil slinger, too.
Does oil come out from between engine and gearbox? Both would point onto that problem, as long as it´s the rear bearing or the rear oil slinger.

Regarding the bearings, it´s more abouthow they are mounted and what internal clearance they have than what make they are. If you take quality bearings with C3 clearance (internal play)you are on the safe side. The best way to mount them would be to do it with temperature difference and without pressing or hitting on the bearings.
owned bikes: 93 Ural rig domestic model, 95 Suzuki DR 650 RSE, BMW R100GS, Suzuki GSX1100G rig, BMW R100R rig with Ural sidecar, Ural rig with BMW drivetrain under construction,

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Fredrikrosen
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Re: Rear main bearing

Post by Fredrikrosen » Fri May 15, 2020 3:45 am

If i remove the rear bearing and it is ok, can i anyway change it to a C3 bearing and keep the front the stock front bearing? Or must both be C3?
Ural 750 Retro -2010
Ural Voyage 720 -1999
Ural 650 Solo Export -1992 :sold
IZH Jupiter-3 -1980
IZH Planeta-5 -1992
Honda CR500R -1984
Dnepr MT16 with BMW engine :sold
Dnepr K650 -1969 :sold
Ural 650 -1993 :sold

Plus another 50+ bikes though the years.

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Re: Rear main bearing

Post by Msblu79 » Fri May 15, 2020 12:32 pm

I also have a 2010 engine and there was a problem with the welder setup that attaches the slingers and roughly 50 engines got out with weak welds. I had one of those and got the same swarf on my drain plug too. I contacted IMZ service (Jason) and he was aware of the issue. I had to return my engine to Seattle (IMZ covered the cost) and Sergey rebuilt it. Been running like a champ ever since. Mine failed during the warranty so it was covered but that was 8 years ago, don't know if they still cover that outside of warranty, Jason can answer that for you. Local dealer may be able to help as well. Not saying that this is what happened to yours but it is a most likely possiblity.
2010 Black Patrol 92,000km's
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Fredrikrosen
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Re: Rear main bearing

Post by Fredrikrosen » Fri May 15, 2020 2:28 pm

Msblu79 wrote:
Fri May 15, 2020 12:32 pm
I also have a 2010 engine and there was a problem with the welder setup that attaches the slingers and roughly 50 engines got out with weak welds. I had one of those and got the same swarf on my drain plug too. I contacted IMZ service (Jason) and he was aware of the issue. I had to return my engine to Seattle (IMZ covered the cost) and Sergey rebuilt it. Been running like a champ ever since. Mine failed during the warranty so it was covered but that was 8 years ago, don't know if they still cover that outside of warranty, Jason can answer that for you. Local dealer may be able to help as well. Not saying that this is what happened to yours but it is a most likely possiblity.
Thanks for good info. :cheers:
Ural 750 Retro -2010
Ural Voyage 720 -1999
Ural 650 Solo Export -1992 :sold
IZH Jupiter-3 -1980
IZH Planeta-5 -1992
Honda CR500R -1984
Dnepr MT16 with BMW engine :sold
Dnepr K650 -1969 :sold
Ural 650 -1993 :sold

Plus another 50+ bikes though the years.

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Fredrikrosen
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Re: Rear main bearing

Post by Fredrikrosen » Sun May 17, 2020 9:26 am

Today i found the reason that i had a metal chip on my drain plug magnet on my -2010 Retro, the front oil slinger was totally loose. On bike used only 6000km! Not ok quality, and obviously was this a defect Ural did know about but never told the owners or did any recall on. I have sent a mail to Ural Europe, i sure hope they will show some goodwill based on the milage. Also did i notice that the front bearing holders bolts had no wire that secures the bolts, another quality issue?

So as Msblu79 informed, it was correct.
Ural 750 Retro -2010
Ural Voyage 720 -1999
Ural 650 Solo Export -1992 :sold
IZH Jupiter-3 -1980
IZH Planeta-5 -1992
Honda CR500R -1984
Dnepr MT16 with BMW engine :sold
Dnepr K650 -1969 :sold
Ural 650 -1993 :sold

Plus another 50+ bikes though the years.

rougaroo
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Re: Rear main bearing

Post by rougaroo » Sun May 17, 2020 10:08 am

Many car manufacturers do a "soft recall" on things that aren't a safety issue. They will do warranty work on the part IF an owner shows up at a dealer with the problem rather than do a mass recall that might cost huge money.

Like msblu79 said, from what I remember IMZ knows the engine numbers or production dates of the bikes with the slinger weld problem. With the very low km's on your bike, I would definitely go to a dealer and have them plead your case.

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Re: Rear main bearing

Post by Fredrikrosen » Mon May 18, 2020 6:05 pm

rougaroo wrote:
Sun May 17, 2020 10:08 am
Many car manufacturers do a "soft recall" on things that aren't a safety issue. They will do warranty work on the part IF an owner shows up at a dealer with the problem rather than do a mass recall that might cost huge money.

Like msblu79 said, from what I remember IMZ knows the engine numbers or production dates of the bikes with the slinger weld problem. With the very low km's on your bike, I would definitely go to a dealer and have them plead your case.

Rougaroo
According to Ural Europe ”was this a unknown” problem that ”they never had heard of”. How unexpected to hear. :mrgreen:

Our guru in the russian Ural Club said that the slingers can be welded back easy with a MIG and that the bearings probably not got damaged this time based on the oil was clean, the engine was clean internaly and there is no radial tolerace or other noticable damage when rotating the con rod. Probably did splash lubrication and some oil reach the bearing via the oil slinger in some way. I hope. :oops:
Ural 750 Retro -2010
Ural Voyage 720 -1999
Ural 650 Solo Export -1992 :sold
IZH Jupiter-3 -1980
IZH Planeta-5 -1992
Honda CR500R -1984
Dnepr MT16 with BMW engine :sold
Dnepr K650 -1969 :sold
Ural 650 -1993 :sold

Plus another 50+ bikes though the years.

rougaroo
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Re: Rear main bearing

Post by rougaroo » Tue May 19, 2020 8:38 am

I would keep up the pressure and communicate with Jason Rae at INZ HQ in Redmond WA. Since the US gets about 90% of Ural's production and so few bikes were affected with the slinger problem anyway, Europe may only have received a few bikes in that production run.

If IMZ HQ authorizes a warranty repair, it will be honored in Europe. I would definitely rather have them do it and install a new D10 crankshaft than have it welded myself.

Rougaroo
2003 Tourist - lotsa upgrades
2004 Troyka - work in progress

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Re: Rear main bearing

Post by Fredrikrosen » Tue May 19, 2020 10:21 am

rougaroo wrote:
Tue May 19, 2020 8:38 am
I would keep up the pressure and communicate with Jason Rae at INZ HQ in Redmond WA. Since the US gets about 90% of Ural's production and so few bikes were affected with the slinger problem anyway, Europe may only have received a few bikes in that production run.

If IMZ HQ authorizes a warranty repair, it will be honored in Europe. I would definitely rather have them do it and install a new D10 crankshaft than have it welded myself.

Rougaroo


According to Ural does US get 50% of the bikes, Europe 40% and the rest to other nations. :deal:
Ural 750 Retro -2010
Ural Voyage 720 -1999
Ural 650 Solo Export -1992 :sold
IZH Jupiter-3 -1980
IZH Planeta-5 -1992
Honda CR500R -1984
Dnepr MT16 with BMW engine :sold
Dnepr K650 -1969 :sold
Ural 650 -1993 :sold

Plus another 50+ bikes though the years.

rougaroo
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Posts: 3913
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Location: NC

Re: Rear main bearing

Post by rougaroo » Tue May 19, 2020 2:25 pm

The essential point was not the relative percentages but the absolute number of bikes produced with the slinger defect and where they ended up. In a 2011 article in the NY Times (https://www.nytimes.com/2011/05/29/worl ... decar.html) , Ural reported selling 650 bikes in the US, representing 60% of their production. That would round up to about 1,100 bikes. If Europe received 40%, that's around 440 bikes. If the problem in production was for a three month window, that's maybe 100 bikes shipped over all the countries of Europe. Those numbers to the US or Europe would depend on shipments being distributed at that constant percentage between the US and Europe, too, which simply doesn't happen. It may also be that more of the problem production run went to the US simply by happenstance.

Rougaroo
2003 Tourist - lotsa upgrades
2004 Troyka - work in progress

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