Author Topic: Apologies another brake bleed Q (Read 1793 times)

STORMY · « **on:** July 11, 2020, 23:38:05 »

Following a question raised somewhere else can somebody please clarify.
I recently changed the brake fluid front and rear systems, but I’ve since found out my bike DL1000 A8 has a linked braking system.
Will bleeding the fluid through and topping up the master cylinders in the usual way completely change all the fluid?
Or is there a specialist dealer tool required to completely remove the fluid from the linked system / ABS unit?
Thanks

Mr Nick · « **Reply #1 on:** July 12, 2020, 14:43:01 »

I think you've been misinformed or misunderstood something: there's no linked brakes that I can see on a Veek unless you're counting the front & rear sharing the ABS unit as being linked. As far as I can deduce, the rear brake pedal only operates the rear brake & the front likewise, so they're not linked.
Download the L4 on workshop manual if you're unsure as the bleed instructions say do the front and rear as separate systems.

STORMY · « **Reply #2 on:** July 12, 2020, 16:09:32 »

I thought the same but face lift models from 2017 onwards (1000) definitely has linked brakes.
Apparently this is the procedure the bike has to go to the dealers where it’s hooked up to a machine which operates the ABS pump & bias valve in a specific order.
The manual on here doesn’t cover the face lift bikes, there’s a few things that differ but obviously it’s still very useful.
I questioned this initially (the linked brakes) and then checked it out - in the marketing blurb from 2017 it’s definitely there.
So a trip to the dealers is looking more and more unavoidable - I’ll check tomorrow and get a definitive answer - now very mindful how much these bloody ABS units cost and keeping fresh fluid circulating around them seems like a rather good idea.

Mr Nick · « **Reply #3 on:** July 12, 2020, 16:52:16 »

I'm looking at the parts fiche for 2018 and 2019 and I can't see anything different in terms of brakes for it over the previous incarnation. ABS unit is the same part, only 2 pairs of brake lines to & from ABS unit so I'm really curious about how they've done it without an obvious part. I can see nothing in the marketing blurb on the 1050 about linked brakes either, which is odd if they still have it. I know how much Guzzi made of the linked brakes, and Honda didn't keep it secret either, so are Suzuki playing it down for some reason?

kwackboy · « **Reply #4 on:** July 12, 2020, 17:37:30 »

I've just had a look and can see nothing about linked brakes on that model ..

Granted, The brake system will share the ABS pump but it's separated internally front and rear.
There shouldn't be any specific equipment needed to change your brake fluid unless the system has trapped air in the ABS.
All you need to do to swap out the fluid is pump it through with the brake levers and keep topping up the reservoir.

For your info, if you somehow did have linked brakes you'd use the same method.

Mr Nick · « **Reply #5 on:** July 12, 2020, 18:52:29 »

The linked brakes on my Guzzis are, in principle, the same to bleed as normal brakes, but in practice are a pain with the linking pipework forming a big high point for any air to congregate as it goes up from the rear cylinder, along the main frame spar, and then back down to the front left caliper. The SP3 is slightly worse with the bias valve creating another potential air pocket.

STORMY · « **Reply #6 on:** July 12, 2020, 19:29:05 »

Here’s a screen shot from some marketing page outlining the main updates on the face lift gen 3 - see point #4.
Don’t get me wrong I want to believe the comments here rather than what I’ve heard elsewhere, once I know for sure I’ll come back and confirm.
When I bled the system the fluid coming through by the end of the process was the new stuff, so I can’t really see what else can be done - anyway like I said I’ll check with the dealer tomorrow Haslemere Motorcycle’s (they’ve got a good rep) it’s bugging me now

Mr Nick · « **Reply #7 on:** July 12, 2020, 19:41:37 »

Ah, what they're really doing is using an inertia sensor to get the ABS to apply some brake pressure rather than physically linking brakes. Don't see why this would change how you change fluid in the same system as before they started using it that way.

kwackboy · « **Reply #8 on:** July 12, 2020, 19:42:37 »

So, I've just looked into this ..

Your brakes are not hydraulically linked but they are electronically.

Here's what I found out ..

The combination system can apply rear brake pressure when the front brake pressure reaches a certain point to help stabilise the vehicle. This contributes to increase stability and maneuverability during cornering.
The rider has customary, independent control of the front and rear brakes unless a situation occurs to activate the Anti-lock or combination braking features.

STORMY · « **Reply #9 on:** July 12, 2020, 19:54:56 »

Quote from: kwackboy on July 12, 2020, 17:37:30

I've just had a look and can see nothing about linked brakes on that model ..
Granted, The brake system will share the ABS pump but it's separated internally front and rear.

I don’t think the brakes work like a traditional linked brake system Honda Pan E, Guzzi’s etc., could it be that under extreme braking it electronically shifts braking power to the rear brake using the IMU?
I admit to not even knowing if this is feasible, but the IMU can definitely reduce braking pressure when you’re cranked over.

STORMY · « **Reply #10 on:** July 12, 2020, 19:59:59 »

Ah OK fellas that sounds plausible, so just to put my mind at rest no need for any additional equipment to bleed the brakes - the procedure I carried out is correct and I’ve been mis- informed else where.
I love this forum there’s some excellent knowledge here

Ianmc · « **Reply #11 on:** July 12, 2020, 21:11:29 »

“Your brakes are not hydraulically linked but they are electronically.”
This is interesting, anyone have anymore info on this, or links to documents please.

Mr Nick · « **Reply #12 on:** July 12, 2020, 22:24:54 »

There seems to be practically nothing published about this system & I'm piecing this together from what I have found.
As I'd said, the L8 on Veeks have an inertia sensor shown on this fiche
https://www.bike-parts-suz.com/Suzuki-motorcycle/1000-MOTO/V-STROM/2019/DL1000A-L9-E21-/SUSPENSION--WHEELS--BRAKES/ELECTRICAL-COMPONENTS/2009000000/2009331608/139/4483 which isn't on previous years. In the blurb Stormy posted, the ABS system is using the inertia sensor for yaw, pitch and roll to (the 'positioning') of the bike to manage the lean ABS and, informed deduction says, to identify heavy braking as well, and combines it with what the ABS sensors are telling it is happening at the wheels to use the ABS pump to apply some braking to the rear.

Advpulse said this in their review of the L8:
'Suzuki also points out that this is a combined braking system, not a linked system. This allows the rider to continue manually controlling the front and rear brakes independently up until the point either the anti-lock system activates or the system detects a need to adjust braking power to the rear.'

Gert · « **Reply #13 on:** July 13, 2020, 08:02:07 »

Some advice that may be of interest, from another V-Strom site: "In order to get the old stale (and corrosive) brake fluid out of the ABS module you need to activate the ABS pump by activating the ABS intervention (front and rear). Do this multiple times. Ideally you change the fluid. Then do like 20 ABS activation on a slippery surface (gravel, grass) at a reasonable speed. Then change the fluid again."

Mr Nick · « **Reply #14 on:** July 13, 2020, 11:00:34 »

That would apply to all ABS equipped bikes then: the theory being that the solenoids are holding fluid and getting them to activate is mixing what is held in those reservoirs with the new fluid, which you flush out again. Not all ABS pumps have nooks & crannies that a normal flush wouldn't access, and Suzuki don't say to connect the diagnostic tool to trigger the pump in their workshop manual, so the unit used on all the Veeks might not require that?
Not sure I would recommend to anyone going out on loose surfaces and deliberately trying to put yourself on the deck trying to trigger the front ABS though: 95% fluid change is probably better than 98% and a dropped bike.

kwackboy · « **Reply #15 on:** July 13, 2020, 19:32:25 »

Agreed... however, the ABS pump should be activated every now and then to keep the Internal workings clear.

The back is easy but activating the front is another level ...

Rusty Nuts · « **Reply #16 on:** July 13, 2020, 19:40:30 »

I'd wondered about that. Most of us would be comfortable tripping the rear abs, but is there a preferred less dangerous work round for the front? Or just "go for it"?

kwackboy · « **Reply #17 on:** July 13, 2020, 19:52:12 »

Yep...
Swallow some bravery pills and go for it...

Personally I've found riding slowly on a gravel road helps.
Applying and releasing the front brake very quickly will activate the abs very easily.

Personally my BMW front ABS will activate if I brake riding over a cat's eye or a slight bump in the road ... Certainly keeps you on your toes

Tusker · « **Reply #18 on:** July 13, 2020, 20:00:32 »

just reading this out of interest and notice the talk is about braking on gravel or grass.. Would practising emergency stops on tarmac not operate front and back ABS ???

UK_Vstrom650 · « **Reply #19 on:** July 13, 2020, 21:45:29 »

Yes it would. The service manual on the Glee states to ride the motorcycle at 30+kph (18.5+mph) and quickly apply the brakes to see it it works. (This is as part of the ABS fault finding)

The best method I've found for triggering the front is to stiffen the front suspension as much as possible, then brake on a bumpy surface or manhole cover.

Edit: another good place to trigger front ABS is the rumble strips on the approach to a roundabout.