Stelvio no front brake ,suspect ABS unit, need help! FIXED !!!

[randy yocum]

My 2012 Stelvio 35.000 miles is giving me some real trouble for the first time.It started a few weeks ago,its winter here so the bikes sits for a couple weeks at a time between rides.What it does is the front brake the lever pulled very hard at first then after a few tries would loosen up and feel normal.It did this every time I'd go for a ride, Till the other day when I couldn't pull the lever at all,no brakes period.I thought It must be gunk built up around the master cylinder piston so yesterday I disassembled it and everything was fine,I tried bleeding the front brakes and I got no movement at the lever ,hydraulic pressure was there but I couldn't get the brake fluid to flow to the front brakes. So I removed the tank to get a look at the ABS unit,I identified the line running from the front brake master cylinder into the ABS unit ,I loosened the brake line and had very good presser there.I reinstalled that line ' then loosened the corresponding output line which goes to the front brakes and could not get fluid to push out that hole where the line attaches .For some reason there is a block inside that ABS unit.I have no experience with this sort of thing,i'm hoping someone out there can tell me how it operates and how to fix it. I was wondering maybe if I could artificially trigger the unit pump to come on it might clear itself,I don't know how to do that either. I looked at the shop manual and they don't even talk about this unit in the manual,strange.

[MotoG5]

In the seven years I had my 12' Stelvio I never had any brake issues so I cant be all that much help. What I do know though is you have to have a program like Guzzidiag or one of the after market products to connect to the bikes ECU in order to cycle the anti-lock for bleeding the brake system fully. I had a program from Techno Research that i used to do tuning and TPS resets but never did use the anti-lock function. I am sure someone will chime in that can help.

[Markcarovilli]

Can’t do anything with brakes using Guzzidiag that I know.  Dealers can with the MG unit....

Mark

[Bulldog9]

My 2012 Stelvio 35.000 miles is giving me some real trouble for the first time.It started a few weeks ago,its winter here so the bikes sits for a couple weeks at a time between rides.What it did was the front brake the lever pulled very hard at first then after a few tries would loosen up and feel normal.It did this every time I'd go to ride, I thought It must be gunk built up around the master cylinder piston so yesterday I disassembled it and everything was fine,I tried bleeding the front brakes and I got no movement at the lever ,hydraulic pressure was there but I couldn't get the brake fluid to flow to the front brakes. So I removed the tank to get a look at the ABS unit,I identified the line running from the front brake master cylinder into the ABS unit ,I loosened the brake line and had very good presser there.I reinstalled that line ' then loosened the corresponding output line which goes to the front brakes and could not get fluid to push out that hole where the line attaches .For some reason there is a block inside that ABS unit.I have no experience with this sort of thing,i'm hoping someone out there can tell me how it operates and how to fix it. I was wondering maybe if I could artificially trigger the unit pump to come on it might clear itself,I don't know how to do that either. I looked at the shop manual and they don't even talk about this unit in the manual,strange.

Random question, is it below freezing? If the brake fluid is old, and loaded with water, could there be ice/frozen water in the ABS pump?

[randy yocum]

No, that's not it,fluid is like new.I'm real careful with my bikes,they get the best of care,and are stored inside.
 

[MotoG5]

Kind of the whole story. When I bought my Stelvio in 2012 I bought a maintenance software kit to enable doing TB balance and TPS resets. The tool had a function that enabled you to cycle open the ABS unit in order to make sure fresh fluid was introduced to it. Other wise the unit just had the old fluid trapped inside. I never did this as for the first few years there were a few times that I actually had to use the ABS so newer fluid was flushed through it. By the time it had been long enough that I thought that I should do the forced flush my old Windows laptop I had the program installed on had died and I soon found out the my program would not run on my new system. The company that I bought the program from no longer supported it so no up grade.
This last year I traded the Stelvio off so I didnt have to get another program. There is one now available from Guzzi Tech that replaces the old tool but you would want to check that it does the ABS force. https://www.guzzitech.com/forums/  Click on the STORE in the banner. Its under electronics.

I am not sure but if your ABS has not been cycled for a long time or at all its possible this might be causing the issue. But I dont have enough direct experience with the ABS to really know. Just throwing out some off hand guesses.

[randy yocum]

Hi Ray,
   Thanks for the help,Yes that is my guess it must be old fluid that has been trapped inside gumming things up. I've owned this bike almost 4 years now and I sure   that I've never activated the front brake ABS, that would only happen during a panic stop and I just haven't had one.Now I can't initiate a panic stop because I can't get fluid to flow through the unit,I pulled on the brake lever to the point of breaking but even that amount of hydraulic pressure won't move fluid through the ABS unit.

[Roebling3]

One would hope that after these many years of development and applications the 'kinks' would be gone. It is a braking system!
My '17 V7 (yclept racer), immediately had no front brake at all. Within ~700 miles the lever pulled to the grip. Zero abs at both ends, but the rear wheel worked well enough to save the bacon, several times.
No amount of bleeding by myself or the dealer (using the factory computer program), worked beyond the next 10 - 12 miles; as the lever would pull nearer and nearer to the grip. **I replaced the frt. Caliper w/a 4 piston Brembo and radial MC w/remote res.** The abs woke up within a day or 2, at the rear. The frt. brake is wonderful. The best I've ever experienced. At my age I've not the testicularity  to test the abs for cycling the front brake. I can easily lift the rear in a stoppie, w/out lock up.
**This brake modification was developed 'in house' by Jim Hamlin -Hamlin Cycles Bethel, CT - and his tech, ~ 5 years ago. Pictures of 'MG Endurance Racing' bikes show what appears to be similar.**
    R3~ 

[Motormike]

this probably won't work, but it's a thought.  Find a dirt or gravel road and try to lock up the "rear" wheel.  If the anti-lock works at all, that might free it up.  I've read where riders swear by cycling the ABS pump and valves that way to keep the unit "fresh."  Most of us never need it until that emergency stopping event.  If that doesn't work, check with Module Masters in Moscow Idaho.  They repair all types of ABS units at a fair price.  https://modulemaster.com/rebuilds/

[pat80flh]

I don't know if it will work but try key on,engine off, rear wheel off ground. Have someone rotate rear wheel while activating front brake. The ABS computer (may) see the non moving wheel as locked and command a cycle. There may also be a minimum vehicle speed you have to attain

[randy yocum]

Good news,I fixed the problem,Today it was near 70 degrees here in central Missouri,Im out enjoying the day riding my 2007 Norge on some of my favorite back roads ,hardly any traffic gave me time to think,think about my dilemma with my Stelvio that's been down for the last week .I been doing allot of studying and watching Youtube videos I found out how these ABS units work and also how they cannot be taken apart,or fixed by guys like us, that's a job for the pros they say.Anyway during my ride I thought if that valve is frozen because of gunk,maybe I can unfreeze it  with heat and liquid wrench, I tried it and it worked.I squirted the stuck orifice full with liquid wrench added heat to the hole and that rod sticking out which is part of the valve, and blew compressed air in the hole after and presto it started working,
   I put it all back together, bleed the brakes, went for a ride ,Its back to normal,I even headed for a flat dirt road and grabbed a handful of front brake (a little unnerving) and sure enough the  ABS unit kicked in and pulsed the bike to a stop.So all is well,I guess the moral of this story is to cycle the system from time to time to flush it out and get some clean brake fluid into that unit.

[Moparnut72]

Harley has had problems with some of their ABS units. They require that owners take their bikes in to the dealership to have the systems bled by a machine which also exercises the ABS system. I think that is a good idea for us to kick in the ABS from time to time. For me it is hard to do with the front end.
kk

[Bisbonian]

Back in the day I had a 1993 Yamaha GTS1000. This was one of the early bikes to have ABS, along with a catalytic converter and fuel injection. The price new, in 1993 was around $15k. I bought mine slightly used for quite a bit less than that.

As you can imagine, a lot of these bikes sat on the showroom floor for quite a while before they were sold. And as you have experience, even after that the ABS was not cycled a lot. These bikes were quite well known to have the hydraulic unit for the abs to be gummed up and the ABS would stop working, sometimes right off the showroom floor. Yamaha even authorized a one-time hydraulic unit replacement regardless of the age of the bike at one point. Mine was 10 years old when they warrantied it.

Web forums were at their earliest when I had mine, but even then the process of cycling the ABS was put out there and a complete brake fluid flush was advised at least annually, to include cycling of the ABS as the fluid in the HU was the most important part to have replaced.

My experience with that bike has kept me away from ABS ever since. Until last week. I guess that part of the preventive maintenance will be to make sure the ABS is activated once in a while to get that fluid cycling so all can be replaced at some point.

[Moparnut72]

At least the brakes work, with some of older Harleys the brakes fail completely. Major recall on those.
kk

[HarveyMushman]

Harley has had problems with some of their ABS units. They require that owners take their bikes in to the dealership to have the systems bled by a machine which also exercises the ABS system. I think that is a good idea for us to kick in the ABS from time to time. For me it is hard to do with the front end.
kk

The Guzzi service machine does the same. Not sure if doing it is spelled out in the maintenance schedule or not. I just periodically cycle the pump while riding.

[pauldaytona]

Randy I suppose you didn't look what these ABS units cost before you put a torch on it :-)

 We do have abs units to start making Guzzidiag work for them.  But it's going to take some time.

[MotoG5]

Great news! Glad to hear that you found a work around. Life was sure easier back in the G5 days. I still am in contact with the guy who owns and is riding and taking care of my old G5. Its still on the road. Loved the Stelvio but it was time to down size due to age. But, the new V9 Bobber has ABS so I may need to do a hard stop from time to time. 

[Waterbottle]

Good news,I fixed the problem,Today it was near 70 degrees here in central Missouri,Im out enjoying the day riding my 2007 Norge on some of my favorite back roads ,hardly any traffic gave me time to think,think about my dilemma with my Stelvio that's been down for the last week .I been doing allot of studying and watching Youtube videos I found out how these ABS units work and also how they cannot be taken apart,or fixed by guys like us, that's a job for the pros they say.Anyway during my ride I thought if that valve is frozen because of gunk,maybe I can unfreeze it  with heat and liquid wrench, I tried it and it worked.I squirted the stuck orifice full with liquid wrench added heat to the hole and that rod sticking out which is part of the valve, and blew compressed air in the hole after and presto it started working,
   I put it all back together, bleed the brakes, went for a ride ,Its back to normal,I even headed for a flat dirt road and grabbed a handful of front brake (a little unnerving) and sure enough the  ABS unit kicked in and pulsed the bike to a stop.So all is well,I guess the moral of this story is to cycle the system from time to time to flush it out and get some clean brake fluid into that unit.

That is a good result Randy 

[Chuck in Indiana]

Desperate times call for desperate measures..