Ducati Scrambler Forum banner

1 - 12 of 12 Posts

·
Registered
Joined
·
10 Posts
Discussion Starter #1
I noticed my front brakes had gotten a little spongy recently, which was surprising as I have only had the bike 4 weeks and it's only done 1800 miles. The only thing I have done is swap out the stock levers for some shorter ones. Anyway riding home from work this evening I realized that the front break had seized on. The brake lever was solid and would not move when pulled in. I had applied the brakes approaching a junction from where I accelerated and noticed the engine bogged down. I pulled over to find the disc was extremely hot, and the bike could not be pushed forward or backwards. I left it for a minute scratched my head and was able to moved off to a safer place where I could have a look. Not sure how but they freed off while doing this and the lever went very soft. I limped home and put the bike in the garage.
I will call the dealer tomorrow, hopefully they will be able to help.

Just wondered if anybody has experienced anything similar.


Sent from my GM1913 using Tapatalk
 

·
Registered
Joined
·
1,563 Posts
I noticed my front brakes had gotten a little spongy recently, which was surprising as I have only had the bike 4 weeks and it's only done 1800 miles. The only thing I have done is swap out the stock levers for some shorter ones. Anyway riding home from work this evening I realized that the front break had seized on. The brake lever was solid and would not move when pulled in. I had applied the brakes approaching a junction from where I accelerated and noticed the engine bogged down. I pulled over to find the disc was extremely hot, and the bike could not be pushed forward or backwards. I left it for a minute scratched my head and was able to moved off to a safer place where I could have a look. Not sure how but they freed off while doing this and the lever went very soft. I limped home and put the bike in the garage.
I will call the dealer tomorrow, hopefully they will be able to help.

Just wondered if anybody has experienced anything similar.


Sent from my GM1913 using Tapatalk
There's your problem. Your new levers have been wrongly fitted, when fitting levers of any kind or price (not just cheap ones) you MUST adjust the push-rod that goes into the master cylinder. If you don't do this either you'll have sloppy brake lever or in your case no clearance at all.
What happens is as the heat build up at the brake pads and caliper the fluid expands and needs to return into the reservoir, if there is no free play at the lever/push-rod it means the return hole is covered leaving nowhere for the fluid to go so it pushes the caliper piston/pads out against the disc, cooking the brake, boiling the fluid and maybe warping the disc. You're lucky you didn't lock up and fall off.
Take the lever off and adjust the push-rod into the barrel until you have roughly 3mm of free play before feeling any resistance at the lever.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #3
Yeah, you definitely have something that I need to look at there. However it doesn't explain why they were spongy and then went rock solid. I've had the new levers on for 2 weeks and never had the caliper seized/bind.

When I say spongy I mean the travel appears to be greater before anything bites. Unlike an old zxr400 that I struggled to bleed properly but when the lever was pumped the brake performance increased.

1st job over the weekend is to put the old lever back on to see what effect this has. 3mm Gap. I don't think I changed the screw setting.

I'll let the forum no if this is successful.

Thanks


Sent from my GM1913 using Tapatalk
 

·
Registered
Joined
·
1,563 Posts
During a pre track day safety meeting at Knockhill here in Scotland they were banging on about recent ‘offs’ at the 1st corner due to cheap Chinese levers. Trying to tell these wally’s that it’s not where they came from that causes it but it’s how the levers are fitted that’s the problem.
Yeah, you definitely have something that I need to look at there. However it doesn't explain why they were spongy and then went rock solid. I've had the new levers on for 2 weeks and never had the caliper seized/bind.

When I say spongy I mean the travel appears to be greater before anything bites. Unlike an old zxr400 that I struggled to bleed properly but when the lever was pumped the brake performance increased.

I don't think I changed the screw setting.



Thanks


Sent from my GM1913 using Tapatalk
Exactly, but you should’ve.
You changed the lever and therefor the swivel acting on the push-rod.
 

·
Registered
Joined
·
3,023 Posts
There's your problem. Your new levers have been wrongly fitted, when fitting levers of any kind or price (not just cheap ones) you MUST adjust the push-rod that goes into the master cylinder. If you don't do this either you'll have sloppy brake lever or in your case no clearance at all.
Listen to this!^^

I had the exact same on my Sled. Chinese levers. And yes, the pushrod was adjustable, but it wasn't properly adjusted when I got them. Too far in (towards the cylinder) and the brakes can block up caused by not freeing the bleeder hole AND feel spongy because not enough fluid can bleed back into the line.
 

·
Registered
Joined
·
1,563 Posts
A spongy brake indicates air present, this can act as a cushion for expansion, when the air makes it’s way out the top as it can sometimes do then you have no cushion. Hence two OK weeks.
 

·
Registered
Joined
·
1,563 Posts
I’ve had to deal with this problem on a few occasions and even customers who have bought expensive levers have needed the adjustment done.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #8
Sorry, was not clear with my last statement. Re changing the screw position, as I was referring to the original lever.

I did experiment with the screw position on new levers to try and get a good bit of the disc.
I'll check for the 3mm.
Cheers.


Sent from my GM1913 using Tapatalk
 

·
Registered
Joined
·
1,563 Posts
When out for a road test, take a spanner that fits the calliper bleed nipple with you incase it happens again.
Don’t sit and let the pads cook against the hot disc, loosen the bleed and the pressure will release right away. Prepare for a squirt of fluid.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #10
A spongy brake indicates air present, this can act as a cushion for expansion, when the air makes it’s way out the top as it can sometimes do then you have no cushion. Hence two OK weeks.
Yeah I get that. I tried to clarify my use of spongy, probs didn't do a very good job.
It's defo not air as the brakes were exceptional when I bought the bike (from Ducati dealer). I only changed them because I dropped the bike and bent the clutch lever and ended up swaping both.

Sent from my GM1913 using Tapatalk
 

·
Registered
Joined
·
10 Posts
Discussion Starter #11
This advise worked well and had solved my problem. After a couple of days riding I now have full confidence in the front brakes again.
Thanks for all the help.


Sent from my GM1913 using Tapatalk
 
1 - 12 of 12 Posts
Top