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Donut question - which one performs best?

Posted: Sun Jun 09, 2019 6:20 pm
by mattzahr
Just noticed some cracks in the "donut" at 17,000 Km....wondering which one to go with - application is 2016 cT - majority of time is spent on slab at 35+ mph - thoughts from the collective with your experiences?

Note - saw the post about polishing the parts by TCF and others - good to know stuff...

Thanks in advance!

Matt

Re: Donut question - which one performs best?

Posted: Sun Jun 09, 2019 6:58 pm
by chaos2
sorry, couldn't resist

Re: Donut question - which one performs best?

Posted: Sun Jun 09, 2019 7:38 pm
by lendrinkard
I don't know. I'm at 30,000 on the same donut. I spray it with silicone a few times a year. I have a spare so I may never need to replace it.

Re: Donut question - which one performs best?

Posted: Sun Jun 09, 2019 8:37 pm
by Bilgekeeldave
I had a donut come apart on my Dnepr at about 8,000 KM. I had a spare and have had no problems with it.
I should get another spare, Does anyone know if a Ural donut is interchangeable with a Dnepr donut?

Re: Donut question - which one performs best?

Posted: Sun Jun 09, 2019 8:38 pm
by Tomcatfixer
wondering which one to go with
Oh, you like polished things? Definitely go chrome, then. :wink:

Just buy one from the dealer and keep it in your trunk 'til your current flexible drive coupler fails (it never will, with the replacement on-hand).

Re: Donut question - which one performs best?

Posted: Sun Jun 09, 2019 8:50 pm
by Lokiboy
mattzahr wrote:
Sun Jun 09, 2019 6:20 pm
Just noticed some cracks in the "donut" at 17,000 Km....wondering which one to go with - application is 2016 cT - majority of time is spent on slab at 35+ mph - thoughts from the collective with your experiences?

Note - saw the post about polishing the parts by TCF and others - good to know stuff...

Thanks in advance!

Matt
Didn’t know there were options? What are they?

Re: Donut question - which one performs best?

Posted: Sun Jun 09, 2019 9:00 pm
by Tomcatfixer
What are they?
Chrome metal band or black metal band. :D

Re: Donut question - which one performs best?

Posted: Sun Jun 09, 2019 10:56 pm
by sKiZo
I couldn't resist either ... <G>

Image

Wonder how deep the cracks go? I've had manifold boots on bikes get to looking pretty bad, but after buying new at a ridiculous price, cut into them and find out it's just surface cracks.

Re: Donut question - which one performs best?

Posted: Mon Jun 10, 2019 6:48 am
by stagewex
I changed mine at about 21,000-22,000 only because I was in the area changing all of the U-Joints from the original Russian non-zerk to new ones with zerk fittings.

The donut was still fine and it is a “spare” in my trunk. Old= chrome band/New= black band. There was an extremely slight difference between the old (bigger) & new.
There was/is no choice of “which” as in performs best as far as I know.

Re: Donut question - which one performs best?

Posted: Mon Jun 10, 2019 8:41 am
by Lee Pape
I prefer glazed donuts from small mom and pop bakeries.

Re: Donut question - which one performs best?

Posted: Mon Jun 10, 2019 9:15 am
by Peter Pan
my donut lasted 39000 km, when the transmission lost its 3rd gear. Since then it is locked in in the tool roll. It is much easier to install a used donut, then a fresh one...
It is more important to have the adjustment circlip on the final drive shaft in the right position (gap 1-3mm) and the phasing right then put a lubricant into the holes.
Although not needed, as occasional lubricant I use Ballistol (German gun oil = equivilant to medical grade "white oil") because it does not attack rubber. (many mineral oils will)

Re: Donut question - which one performs best?

Posted: Mon Jun 10, 2019 10:14 am
by stagewex
I should have added the minuscule difference in size (old to new) made no difference in the location of the circlip. But it's very important for you to either make a mental note of take a digital picture of where the clip is when you are dismantling.

Equally important is making sure you "phase" everything when you are done. Makes a huge difference in performance and you'd be surprised how often it's incorrect by the set-up dealers themselves.

I've never lubed or coated my original or replacement donut with anything and saw no real break-down or spidering after 10 years of sometimes hard-core service. But if others think it helps with slowing down deterioration then great. It is a perishable.

Re: Donut question - which one performs best?

Posted: Mon Jun 10, 2019 10:37 am
by mattzahr
Tomcatfixer wrote:
Sun Jun 09, 2019 8:38 pm
wondering which one to go with
Oh, you like polished things? Definitely go chrome, then. :wink:

Just buy one from the dealer and keep it in your trunk 'til your current flexible drive coupler fails (it never will, with the replacement on-hand).
Chad - if it ain't polished, paint it...correct????

Think I'll go with the black band like the OEM currently on the bike. I appreciate the pointers on the white oil for lubrication, phasing, and the cartoons for reference - now I have an idea of what to sit on while I work and what to snack on...... :lol:

Re: Donut question - which one performs best?

Posted: Mon Jun 10, 2019 2:43 pm
by sKiZo
Is playing with the phase even necessary if you carefully mark the positions of the shafts? I'm talking a 1W drive on a 2011 if that makes a difference.

Also, is donut failure a real issue if you don't beat the bike? All two lane highway for me, with an occasional jaunt down a gravel road if I get lost ... <G>

Re: Donut question - which one performs best?

Posted: Mon Jun 10, 2019 2:44 pm
by Peter Pan
Ain't it amazing how many different answers and tips you recieve on one simple question?
There ain't no "Yes, Sir", or "No, Sir" anymore when you ask in a forum like this...
I love it.

Phasing is a big issue in deed. Once I wondered why my sidecar wheel was throwing sand in intervalls while a buddy used it...its shaft was out of phase and the s/c wheel too fast too slow with every turn.
You noticed right away after changing the set up that the riding in 2WD became less strange. Anyway its still or straight or straight.