Jump to content
Sign in to follow this  

Losing Front Brake lever pressure

Recommended Posts

Wondering if anyone has had this problem. I had a nice get off through the woops, bent subframe, bent bars and cracked top of the brake fluid reservoir where the hot start attaches. I replaced the brake reservoir cap and bled the line but had no pressure. Then pumped the lever and got pressure in the line then it went soft again after the bike sat. Any ideas where to look.. There is no apparent leaking to b e found.

Share this post


Link to post
Share on other sites

could be air in the system.

park the bike with the brake lever pull in with some kind of rubber band to hold it. the pressure should build up over night.

if not, you have to look again.

Share this post


Link to post
Share on other sites

The sure fire way to fix it ; Loosen the caliper and have a helper to hold it at higher level than the MC.Air works its way at the highest possible point. Bleed the brakes as you normally would but keep the caliper/bleeder screw over the level of the MC. As said you´ll need a helping hand for this.

After you have a firm lever bolt the caliper back on. Leave the MC cover off still. Push the caliper against the brake disc (you want to push the pistons in all the way) but be careful so you don´t tweak the disc. After you get those pistons pushed in pump up the pressure once again,fill the MC and bolt on the cover. Now you should have World Class front brake.:lol:

I actually top off the MC until brake fluid overflows and first then i mount the MC cover. This leaves the reservoir without any air which in turn eliminates the following ( and i´m sure this is exactly what happened when you crashed ); Often when you fall/crash (as in corners etc.) you hold the brake lever in. If the reservoir isn´t totally filled up there´s an air space/bubble inside it. Once the bike leans over as far as it does in a crash the air bubble gets inside the system while you hold the "passage" open/lever in.

Share this post


Link to post
Share on other sites
The sure fire way to fix it ; Loosen the caliper and have a helper to hold it at higher level than the MC.Air works its way at the highest possible point. Bleed the brakes as you normally would but keep the caliper/bleeder screw over the level of the MC. As said you´ll need a helping hand for this.

After you have a firm lever bolt the caliper back on. Leave the MC cover off still. Push the caliper against the brake disc (you want to push the pistons in all the way) but be careful so you don´t tweak the disc. After you get those pistons pushed in pump up the pressure once again,fill the MC and bolt on the cover. Now you should have World Class front brake.:lol:

I actually top off the MC until brake fluid overflows and first then i mount the MC cover. This leaves the reservoir without any air which in turn eliminates the following ( and i´m sure this is exactly what happened when you crashed ); Often when you fall/crash (as in corners etc.) you hold the brake lever in. If the reservoir isn´t totally filled up there´s an air space/bubble inside it. Once the bike leans over as far as it does in a crash the air bubble gets inside the system while you hold the "passage" open/lever in.

+1, its a good idea to flush the system while your bleeding, fresh fluids= happy brake system.

Share this post


Link to post
Share on other sites

With a crash that hard (that managed to damage the m/c cap) also replace the banjo bolts and the crush washers in the system. They could be tweaked lightly and causing air to get in.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×