Donut question - which one performs best?

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mattzahr
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Donut question - which one performs best?

Post by mattzahr » 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
'16 cT - Terracotta 22k and climbing
2016 Kawasaki Ninja 300
2009 HD Heritage Classic (wife's)
2021 Kawasaki Ninja 400 X 2 (kid's)
Former bikes
2005 HD Springer Classic
1983 BMW R80RT
1998 Ural Italia
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Re: Donut question - which one performs best?

Post by chaos2 » Sun Jun 09, 2019 6:58 pm

sorry, couldn't resist
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Re: Donut question - which one performs best?

Post by lendrinkard » Sun Jun 09, 2019 7:38 pm

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.
2012 Gear up - 130/40 jet, 3 shims, no mid-pipe, drilled slider, 2013 Branch pipes, all LED lights
2013 NOS Ural T - 130/42 jet, 2 shims, LED running lights, oil cooler

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Re: Donut question - which one performs best?

Post by Bilgekeeldave » Sun Jun 09, 2019 8:37 pm

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?
Dave

RAMCO-Dnepr MT-16

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Re: Donut question - which one performs best?

Post by Tomcatfixer » 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

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, 2007 BMW K1200GT

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: Donut question - which one performs best?

Post by Lokiboy » Sun Jun 09, 2019 8:50 pm

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?
2011 Gear Up - "Erika"
Yorktown, VA

Mains: 127, Idle: 40, Needle: 1 shim
MKIII air filter
100,000 km and counting

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Re: Donut question - which one performs best?

Post by Tomcatfixer » Sun Jun 09, 2019 9:00 pm

What are they?
Chrome metal band or black metal band. :D
- 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, 2007 BMW K1200GT

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: Donut question - which one performs best?

Post by sKiZo » Sun Jun 09, 2019 10:56 pm

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.
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2011 Ural T
Handicap mods include Raceway foot box, tank shifter w/reverse, and DIY rear brake pedal mods.

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Re: Donut question - which one performs best?

Post by stagewex » Mon Jun 10, 2019 6:48 am

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.
Stagewex

Current Herd all running amok:
2019 Honda CRF450L (Elec Start)
2008 Vespa 150S (Elec & Kick Start)
2007 Ural Patrol (2WD, Elec & Kick Start)
2006 Honda "Big Ruckus" PS250 (Elec Start)
1991 Honda XR250L (Kick Start Only) *NOT running amok, out for Bottom & Top-End Rebuild.
1986 Yamaha BW200ES (Elec & Kick Start)

List what you "have", keep the others in your precious memory bank.

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Re: Donut question - which one performs best?

Post by Lee Pape » Mon Jun 10, 2019 8:41 am

I prefer glazed donuts from small mom and pop bakeries.
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Peter Pan
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Re: Donut question - which one performs best?

Post by Peter Pan » Mon Jun 10, 2019 9:15 am

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)
Sophie Travelair = Patrol 2013
8 weeks 12.000km Oregon-Alaska-Oregon
With a DIY foam air filter the rig runs well even in tropical rain = :moto:
Final drives: 1. at 5000km, 2. at 34.000km(+friction plates) 3. at 42.386km
transmission: 1. 40.000km. 2. installed
Engine: 1. 43.388km crank replacement: Back on the road since 23.Okt.2019 :party:

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=> Attitude makes the difference!

stagewex
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Re: Donut question - which one performs best?

Post by stagewex » Mon Jun 10, 2019 10:14 am

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.
Stagewex

Current Herd all running amok:
2019 Honda CRF450L (Elec Start)
2008 Vespa 150S (Elec & Kick Start)
2007 Ural Patrol (2WD, Elec & Kick Start)
2006 Honda "Big Ruckus" PS250 (Elec Start)
1991 Honda XR250L (Kick Start Only) *NOT running amok, out for Bottom & Top-End Rebuild.
1986 Yamaha BW200ES (Elec & Kick Start)

List what you "have", keep the others in your precious memory bank.

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mattzahr
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Re: Donut question - which one performs best?

Post by mattzahr » Mon Jun 10, 2019 10:37 am

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:
'16 cT - Terracotta 22k and climbing
2016 Kawasaki Ninja 300
2009 HD Heritage Classic (wife's)
2021 Kawasaki Ninja 400 X 2 (kid's)
Former bikes
2005 HD Springer Classic
1983 BMW R80RT
1998 Ural Italia
Other toys
2014 EZ GO Golf Cart Limo (gas)

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Re: Donut question - which one performs best?

Post by sKiZo » Mon Jun 10, 2019 2:43 pm

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>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Evil Kneivel? He got nuttin' on me!
2011 Ural T
Handicap mods include Raceway foot box, tank shifter w/reverse, and DIY rear brake pedal mods.

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Re: Donut question - which one performs best?

Post by Peter Pan » Mon Jun 10, 2019 2:44 pm

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.
Sophie Travelair = Patrol 2013
8 weeks 12.000km Oregon-Alaska-Oregon
With a DIY foam air filter the rig runs well even in tropical rain = :moto:
Final drives: 1. at 5000km, 2. at 34.000km(+friction plates) 3. at 42.386km
transmission: 1. 40.000km. 2. installed
Engine: 1. 43.388km crank replacement: Back on the road since 23.Okt.2019 :party:

The Avatar are 2 rice grains stating life's essence:
"The most important you cannot see!"
=> Attitude makes the difference!

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