So, my motorbike had a leak, put in the garage (main dealer, although only a small family run one) and they found a coolant leak. Whilst it was there they also found the front brake to be soft, so advised I get it adjusted.

ABS bike, so needs diagnostics but they did that and they found the pistons were no moving on one side. Rebuilt my caliper (both sides) and the brake felt strong. Within 2 miles of me riding home, the front brake locked on (assuming it heated up) and I (apart from ****ting myself) managed to get out of traffic sliding on my front wheel.

They came and got it from the road side and after waiting I called them late the next day. They said they have checked the brakes and everything seems ok, they can't replicate the issue so assume it's a master cylinder fault. £100 and free labour for the trouble.

Now I'm struggling a bit, they claim this fault would have been there before, yet in two years my brakes didn't fail me.

Any thoughts?

 

Request the old master cylinder and send it away for an independent investigation. Very dangerous situation you ended up in there.

 

Abs brakes don't need diagnostic for items like seized pistons. Just a good rebuild. I would suspect the pistons didn't retract and pressing against disc got pads and disc really hot. Thus jamming front wheel with expansion. That's why later fault cleared by cooling down. A good check of piston movement is vital before blaming other parts of system.

However if you've left bike in poor condition and brake fluid has got water in it, caused internal corrosion, then more than one part of the system could of failed

 

It's not a fireblade is it? The ABS fireblades are well known for ABS issues.

 

No, it's a Shiver and it's still in the shop a week later .. no news from them.

 

Bike is in great condition, well maintained and looked after.

 

Well in that case, check calipers are working as described, pistons move out on pressure and slightly retract when lever let go.

I've had a similar incident when braided lines were fitted to my car, for then to have a caliper jam later. It turned out one of the hoses had a burr obstructing the fluid, so under pressure the pistons could move outward but under low return pressure fluid wasn't able to retreat.

 

Still not got the bike back, shop doesn't answer the phone or reply to email.

Have contacted Aprilia UK to make a complaint about them. Not use if they have any control but the place is a dealer.