Author Topic: Spongy Lever after Pad Change - help! (Read 4544 times)

porter · « **Reply #20 on:** March 22, 2021, 12:29:11 »

Maybe you moved one or more of the brake pistons out to far and drue air in that way. I popped one right out last pad change and it was a bugger to bleed again. I've changed pads three times and the master cylinder before and had no trouble like this before. Hope they sort it for you.
Ps used DP pads this time, have tried SBS and EBC and wow what a change, super strong brake, will take a bit of getting used to.

FragglePete · « **Reply #21 on:** March 22, 2021, 13:01:09 »

Definitely didn't pop out the pistons too far.

Pete

Ianmc · « **Reply #22 on:** March 22, 2021, 14:41:56 »

Just before Christmas I took both calipers off, removed the pistons, cleaned up and fitted new seals,re-assembled and bled the system with no problems.A good tip if you have a spongy lever ,is get someone to give you a hand, get them to pump the lever up to a decent pressure and hold it whilst you bleed the caliper, open the bleed screw quite a bit when you do it to get a good fluid flow and then close it just as the lever gets to the grip, do this several times starting with the furthest bleed screw from the master cylinder, even if you think you have all of the air out.

Sage · « **Reply #23 on:** March 22, 2021, 16:09:19 »

Porter, which DP pads did you use, they are listing two for the front ?

porter · « **Reply #24 on:** March 22, 2021, 18:02:45 »

DP spd+HH. Not the titanium ones. I see some listed on ebay but the price has went up from the 40 quid I paid!
Remember with a 14 on vstrom you can look at 09 gsxr front pads as there the same caliper and then you don't have to pay the adventure bike tax!

Gert · « **Reply #25 on:** March 22, 2021, 19:51:54 »

By how much did you turn the bleeder screw loose, when bleeding the brake calipers? One has to basically crack them just enough, to allow any fluid pressure to escape from the system. Opening / loosing the bleeder too much, could allow for air to be sucked back into the system.

FragglePete · « **Reply #26 on:** March 22, 2021, 20:07:45 »

I have a one man bleeder kit, which has a valve in the end which stops air being sucked back in. Used it for many years with no issues.

Most odd.

Pete

porter · « **Reply #27 on:** March 23, 2021, 09:24:52 »

I to use a similar bleeder to force the new fuild through the system but remove it once its through and bleed as normal, ie jam jar and small peice of pipe, loosen the nipple a fraction, pump and hold the brake lever, tighten the nipple, repeat many times! Tape up the brake lever overnight as well as this seems to help.

FragglePete · « **Reply #28 on:** March 23, 2021, 13:00:06 »

I've had the brake lever strapped overnight, and some pressure has come back but braking effort is still poor.

It's booked in, transport arranged and just want to get it sorted.

Pete

Brockett · « **Reply #29 on:** March 23, 2021, 17:33:56 »

Recently with an empty system I filled the reservior and then attached a 6ft long plastic tube over the bleed screw. The tube was suspended high above the bike. I backed out the bleed screw half a turn and pumped the lever to release fluid with air bubbles which could be seen in the plastic tubing. I kept pumping and refilling with the bleed screw left open open until the air bubbles had risen up the tube a good distance. I never use old fluid so it doesn't matter if I use a lot of fluid in this method. When the fluid came out cleanly with no bubbles with each I pump I locked off the bleed nipple and then put pressure on the lever for a minute or so. Then while holding pressure on the lever I opened the bleed screw a small amount and saw some more small bubbles. I continued pumping the lever and topping up the reservior until bubbles no longer appeared and locked off the bleed screw. Eventually the brake pressure was spot on and all soggyness was gone. To remove the tubing I lowered the high end of the plastc tube and drained the fluid into a container below the level of the bleed screw. This prevented the fluid in the tube spilling out onto the caliper and wheel.

Silverback · « **Reply #30 on:** March 24, 2021, 18:47:16 »

My apologies if this have already been mentioned but have you tried bleeding from the banjo bolt at the master cylinder? Had a similar thing happen to me after hours of frustration trying to get a brake.........gently squeezed the brake whilst loosening the banjo bolt and Hello presto my brake is back. Air can get trapped there as it's a high point in the system. Worth a try if you haven't already.

FragglePete · « **Reply #31 on:** March 24, 2021, 18:54:27 »

Yes - I did try the bleeding the banjo bolt at the master cylinder. It was something a good friend of mine suggested who runs a motorsport service department in the USA.

Interestingly, strapping up the lever overnight does bring a small bit of pressure back, but I can still pull the lever back to the stop with not much breaking effort.

I appreciate everyone's input with this - but, it gets to the point you have to admit defeat as I may just cause more issues if I keep plodding away at it. It's booked in next week, let a pro take a look and I'll take the hit and wear the cone of shame as I get lectured about what I did wrong from the mechanic. Gets to the point, I just want my bike back so I can start enjoying it as I've done less than 200 miles on it since I've got it.

I'll report back when its all up and running again.

Pete

Silverback · « **Reply #32 on:** March 24, 2021, 19:10:48 »

The only other thing I can think off is that as you pushed the pistons back to accommodate new pads the dust seal came out of its seat and has snagged between the piston and cylinder? Believe it or not those seals can stick themselves to the pistons.....I've had that happen. Good luck.

Mr Nick · « **Reply #33 on:** March 24, 2021, 21:10:27 »

The rear master cylinder seals failing caused a similar issue on my SP3 last year - hadn't gone completely but just wouldn't build enough pressure to operate the brakes. Thankfully Brembo units are an easy fix.
Hope your mechanic gets to the bottom of it cheaply.

Gert · « **Reply #34 on:** March 25, 2021, 06:42:49 »

Have you tried slacking off the relevant banjo bolts, to help bleed this so called "air bubble". As long as the master cylinder is under brake lever pressure, the chances of air being sucked back into the brake lines should be minimal to zero during the bleed process.

FragglePete · « **Reply #35 on:** March 30, 2021, 16:40:25 »

I pleased to say that I've got my Veek back!

The garage managed to get it done quicker than I expected, so picked it up this afternoon and it's now safely home.

They had to re-positioned the throttle bodies as the way somebody had put it back together beforehand prevented proper brake operation. Once sorted, they managed to get it all bled. As they had dealt with this issue before, they managed to get it done quickly. That, with sorting my centre stand out with tapping in a heli-coil and new bolt it wasn't too expensive overall. £86 lighter, but worth it to get it sorted.

I asked about what the correct procedure is for doing this, and they just recommended leaving it alone if it's got ABS on it and get it done properly. He acknowledged it sounds like "just spend the money with us", but just felt very strongly on getting a workshop done on any bike (especially with Suzuki's) that have ABS.

So, next is to get a taller screen on it. Although it has a MRA screen on it with a flip up wing on it already, the buffeting down the short blast of the Motorway was quite annoying so need something a smidge taller I feel.

Pete

Keith60 · « **Reply #36 on:** March 30, 2021, 16:53:54 »

£86 sounds like good value to me!!

porter · « **Reply #37 on:** March 30, 2021, 19:48:54 »

Glad you got it sorted and not to expensive. Can't agree with your mechanic though, I've drained the system down 3 times on mine ( two master cylinder changes and the top brake line) with no trouble, just bleed as normal.
The givi airflow works better than the mra screen, I have both, just use the mra in the summer months for more air, looks better to. Good luck.

WeeStromer · « **Reply #38 on:** March 30, 2021, 20:25:49 »

Glad you're sorted! £86 sounds alright to me.

Gert · « **Reply #39 on:** March 31, 2021, 07:18:07 »

Don't forget to activate the ABS from time to time. If you are able to find a bit of dirt or gravel, it will be easy to activate the ABS at a very low and safe speed. You are looking to feel the brake lever pulsing, as the ABS activates / controls brake lockup.