Noob life—rear brakes not working

Woe unto you that bought the first model year of a major remake, perhaps this section can help address any 2014 and later model Ural "imperfections". Here's a special section for folks with the latest rigs to discuss 2014 and later model-related topics such fuel injection, 3-wheel disc brakes, hydraulic steering dampers, spin-on oil filters and other anomalies that don't belong on true Russsian motorcycle ;-P We've gone from using big hammers and greasy wrenches to needing computers and Ouija boards in order to fix our rigs.
Forum rules
Please keep this section specific to issues pertaining to 2014 and later models such as fuel injection, sidecar and rear disc brakes and so forth. Ask general or non-2014 and later specific questions in the main Hammerin' & Wrenchin' section.
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windmill
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Re: Noob life—rear brakes not working

Post by windmill » Mon Jan 28, 2019 12:42 pm

eastbloc wrote:
Mon Jan 28, 2019 12:22 pm
I think I read somewhere that the caliper for the rear brake is in fact not used on countless motorcycles, but was designed for a Polaris three-wheeler. Few motorcycles need a parking brake.
Yes, your correct, it's used on ATVs, and Spyders, tens of thousands of ATVs, and Spyders.

The potential issues are the same, for the same reasons.
Last edited by windmill on Mon Jan 28, 2019 1:08 pm, edited 1 time in total.
Barry

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2007 Patrol 100k km and counting,
2018 M70

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Re: Noob life—rear brakes not working

Post by windmill » Mon Jan 28, 2019 12:46 pm

harryball wrote:
Mon Jan 28, 2019 12:29 pm
Having an M70/Retro that has had rear brake issues from day 1 (brake hose was chewed up due to bad routing by not me) and not being able to get the right parts from Ural, I have done it all with the rear brake caliper. I have bled brakes on the rear about a dozen times in the past 6 months. So, I use a "top end oil replacement pump" that sucks oil.

1) remove caliper to a) make it LOWER than the master cylinder and b) point the bleed port up.
2) fill up the brake reservoir with brake fluid.
3) put a 1/4" hose onto the nipple connected it to my oil vac and pump it up as much as possible.
4) crack open the bleed port and let it suck at least 1/2 the fluid through from the reservoir then close the port
5) Fill up the reservoir, pump up the pump and repeat 4
6) Repeat 5
7) Remove the pump, reinstall everything, top off brake fluid to the right level and pump the brakes.
8) adjust your parking brake

Like I said, I have done this at least a dozen times in the past 6 months, did my wife's brakes using this method too. Works well and every time.

Caveats:
The larger the pump the better it works, plenty of air volume sustains enough vac not to run out while moving fluid. If you use a smaller pump, just move less fluid each time and run it more often. The goal is for it to aggressively SUCK the fluid through purging air.
Using a compressed air venturi oil pump works well too.
Leave some used oil in your pump before introducing brake fluid and flush after the brake fluid with a bit of used oil too. i.e. brake fluid can be tough on the pump seals, The used oil dilutes

Hope that helps someone.
Pay close attention to the fluid level in the reservoir, or have lots of fluid on hand...... don't ask how I know.....
Barry

"Take care, sir," cried Sancho. "Those over there are not giants but windmills".

2007 Patrol 100k km and counting,
2018 M70

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Re: Noob life—rear brakes not working

Post by rivers » Mon Jan 28, 2019 2:31 pm

HassoBoxhead wrote:
Sun Jan 27, 2019 9:38 pm
There must be instructions somewhere....
If you're just starting out learning brake bleeding, I highly recommend reverse pressure bleeding. Mitymite etc vacuum pumps sorta work occasionally but not recommended. Google "DIY pressure brake bleeder." You can build your own from a plastic 1/2 gal garden sprayer for $50 w/pressure gauge. Buy enough hose and you can bleed the rear brakes on a car/PU truck while watching the the master cyl fluid level in the eng bay. No need to remove calipers to orient the bleed nipples.
Flushing brake fluid is an on-going 'important' maint/safety procedure. I do bikes every year and cars/trucks every two. Lot cheaper to buy fresh brake fluid than replacing expensive rusted/corroded internal parts.
Joe
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Re: Noob life—rear brakes not working

Post by Mr Wazzock » Mon Jan 28, 2019 6:46 pm

harryball wrote:
Mon Jan 28, 2019 12:37 pm
check that your brake peddle is not maintaining pressure on the brake master cylinder. I found that the "adjustment" on the brake peddle was causing the master cylinder to ALWAYS be under slight pressure.
Image this

Should be about 1mm play in the actuator rod, i.e. pedal can go down a bit before it actually contacts the master piston.

Have I mentioned caliper piston can be seized or stiff, I recommend to give it a light coat of brake grease to try keep corrosion at bay.

HTH
Mike H
2016 Ural cT, in glorious terracotta
(aka Oranzhevaya Opasnost, "The Orange Peril")

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Re: Noob life—rear brakes not working

Post by hotflash44 » Mon Jan 28, 2019 7:52 pm

HassoBoxhead wrote:
Sun Jan 27, 2019 5:56 pm
Thanks all for the replies. Is there a step-by-step, noob-level link for bleeding the rear brakes?
curiosity is killing me, please let us know what the cure is. :cheers:
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Re: Noob life—rear brakes not working

Post by HassoBoxhead » Sat Feb 02, 2019 8:51 pm

Well, the culprit was me not backing off the parking brake adjustment to release the pistons...thank you all for your patience with my noob-ness! Back on the road and just a wee bit smarter to boot...
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Re: Noob life—rear brakes not working

Post by hotflash44 » Sun Feb 03, 2019 7:43 am

HassoBoxhead wrote:
Sat Feb 02, 2019 8:51 pm
Well, the culprit was me not backing off the parking brake adjustment to release the pistons...thank you all for your patience with my noob-ness! Back on the road and just a wee bit smarter to boot...
perfect,glad it worked for you, i also will file that parking brake adjuster back off info for when i do the rear brakes on my 2016. :cheers:
2016 gear up asphalt grey, name Seryy Medved ,Air America CIA circa 1967/8 Vung Tau Viet Nam USS Tutuila ARG-4 (AND JUST A TOUCH OF AGENT ORANGE!)

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Re: Noob life—rear brakes not working

Post by HassoBoxhead » Sun Feb 03, 2019 10:33 pm

I guess I’m officially hooked on this rig...being off of it for a week just plain sucked, today with temps in the 50’s and sunshine, with a healthy Ural, was just plain fun.
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Re: Noob life—rear brakes not working

Post by HassoBoxhead » Sun Feb 03, 2019 10:34 pm

Thanks again to all those that responded!
2014 Slate Grey Gear Up
Retired Air Force Russian Linguist
“Too Close for Missiles, Switching to Guns”

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