Author Topic: V7 II (ABS) - Rear Brake Not Pressurizing  (Read 2230 times)

Online Dirk_S

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V7 II (ABS) - Rear Brake Not Pressurizing
« on: January 15, 2023, 09:37:33 AM »
Since getting the bike back together, the past 30 miles have been going well EXCEPT I still can’t get the rear brakes to pressurize after a few attempts of bleeding and priming. If I pump the foot lever multiple times fast enough, I do build up pressure, but it quickly loosens up. During the first few pumps, I hear air movement in the lines to/from the ABS module. So, I have no rear brake.

I initially used a syringe to prime the line up via the caliper bleed port. Then I proceeded to bleed… and bleed… and bleed, via the reservoir—Pump, pump, pump > lever depressed > crack the bleed 1/4 and close back up quickly > repeat > fill reservoir as needed. No progress, and I feel I’ve done it enough times by now…

I’ve read that brakes fitted with ABS can hold more air and require more bleeding, and I see the ABS module sits in-line with or possibly higher than the reservoir. I also wonder if perhaps during the engine removal or installation—or while the frame sat outside during the 3 months it took me to rebuild—if the ABS module or it’s lines might’ve been damaged.

I checked all the nuts—everything’s tight. I figured my next step is to spray some soapy water to check for leaks. Anything else I can do to troubleshoot? I have GuzziDiag, and I know there was some ABS support added in, but I’m not completely sure what all it can check.

No alarm/light, so I reckon the module itself isn’t the problem.
« Last Edit: January 15, 2023, 10:05:33 AM by Dirk_S »
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Re: V7 II (ABS) - Rear Brake Not Pressurizing
« Reply #1 on: January 15, 2023, 11:01:59 AM »
The only way to get the air out is to remove the caliber, get it higher than the ABS unit then bleed.
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Offline Air-Cooled

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Re: V7 II (ABS) - Rear Brake Not Pressurizing
« Reply #2 on: January 15, 2023, 11:38:32 AM »
Yes, that caliper is a down-low


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Online Dirk_S

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Re: V7 II (ABS) - Rear Brake Not Pressurizing
« Reply #3 on: January 15, 2023, 11:46:42 AM »
Yes, that caliper is a down-low


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Yeah, I learned previously with my Honda CX500 that when bleeding it’s best to turn those calipers so the nipples are facing upward, but I did that, and am still not gaining pressure. Maybe I’m just not doing it right. I’ll try some more.

The only way to get the air out is to remove the caliber, get it higher than the ABS unit then bleed.

I hadn’t thought about that, mainly because I never had to do it before. Guess that means bringing the caliper around to the other side so all the hosing can stretch up. I’m assuming the lines also should be elevated, but the ones going in and out of the module are rigid.
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Offline guzzisteve

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Re: V7 II (ABS) - Rear Brake Not Pressurizing
« Reply #4 on: January 15, 2023, 01:14:42 PM »
The only way to get the air out is to remove the caliber, get it higher than the ABS unit then bleed.
THIS and sometimes you have to feed it through so line is strait. To do that maybe wheel out or stuff moved. It does bleed through the pump with key off. Don't forget to put a wrench between pads.
I was doing alot of this so I bought a canister for air compressor line. Worth every penny.
The holes are smaller than they used to be.
« Last Edit: January 15, 2023, 01:16:09 PM by guzzisteve »
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Re: V7 II (ABS) - Rear Brake Not Pressurizing
« Reply #5 on: January 15, 2023, 01:15:38 PM »
And we have brakes! Elevated the caliper and within a few pumps the air was out of the system. Easy peasy; thank gawd it wasn’t a leak or module issue.

Funny that Guzzi doesn’t mention removing the rear caliper for bleeding/purging.

Much appreciated, Vagrant, Air-Cooled, and Guzzisteve!
« Last Edit: January 15, 2023, 01:16:26 PM by Dirk_S »
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Offline nursed

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Re: V7 II (ABS) - Rear Brake Not Pressurizing
« Reply #6 on: April 26, 2025, 11:34:43 PM »
Trying to do this and got a bit of air out but I'm worried that the caliper can't get high enough due to the hoses. I can mange teh seat, but not much higher.

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Re: V7 II (ABS) - Rear Brake Not Pressurizing
« Reply #7 on: April 27, 2025, 06:33:53 AM »
Unbolt & raise the caliper, I used bungee cords to hook it to an eyebolt i had in the garage ceiling. After that it went very quckly
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Offline jhem68

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Re: V7 II (ABS) - Rear Brake Not Pressurizing
« Reply #8 on: April 27, 2025, 07:39:20 AM »
After removing the rear caliper remove the clips securing the line crossing over from the RH side of the bike. Then pass the caliper through the area between the front of the rear wheel and under the swingarm pivot ( you might have to remove the RH muffler, I can't recall). Then elevate to about the level of the top shock mount. Bleed as per normal and retrace your steps to remount the caliper, worked for me.

My Milano was on the centerstand when I did this procedure, so in an upright position NOT leaning over on the sidestand.

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Re: V7 II (ABS) - Rear Brake Not Pressurizing
« Reply #9 on: April 27, 2025, 11:06:22 AM »
Just my $.02 , Invest in a couple of speed bleeders . It makes routine brake fluid changes much easier .

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Re: V7 II (ABS) - Rear Brake Not Pressurizing
« Reply #10 on: April 27, 2025, 12:35:07 PM »
Literally, just done my one on the V7III CS. From purchase, the rear brake was ineffective - so much for the dealer "service"! I finally got around to it, now that the garage is somewhat warmer to work in. I was pre-warned by previously doing the Breva, so knew what had to be done.. a combination of the previously mentioned stuff.

Unclip ABS/speed sensor cable from the brake line.
Remove retaining clip on swingarm underside - the stud came out, rather than the nut.
Detach rear caliper, passing it through the gap between the swingarm and right silencer.
Hang the caliper from a bungee, to just below upper shock mount.
Stuff aluminium sheet between the brake pads.
Use a cheap Chinese "easy/one-man bleeder". This has a metal encased one-way valve, compared to the often seen plastic ones (eg. EZ-Bleed), which I find to be unreliable.

Thanks @Dirk_S for kicking me up the butt to get this done.  :thumb:
« Last Edit: April 28, 2025, 03:59:56 AM by DoubleGuzzi »
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