Holy cow, never had this before.

[FROSTY:Me]

Our latest project bike had me stumped. Brake lever diddn't move--as in siezed rock solid. Bikes been standing at least 8 years so no suprises there.Took the master off and started the degunge process. Accidently flicked the lever and HMM it moved normally. -ODD but ok then the caliper pistons must be siezed then. Off with one caliper and--er hang on clean hmp grease and hitting it with the airgun has the pistons flying in and out easilly. HU???
Ok so its gota be the joint. NOPE
Well bugger me blow through the brake lines and theyre all gunged up totally solid.--NOTHING moving inside em.
New one by me I must say.

[Cajun]

time for new brake lines me thinks.

[imdying]

When I get those I put 4000 psi through (air over hydraulic tester, all hoses are tested to that before they leave the hose making room) them to see if they'll clear

Sometimes they won't, so I'll cut em up to see what the heck happened, sometimes they will and a bit of rooted rubber will fly across the room like a bullet OSH would have kittens

[FROSTY:Me]

yea but what would make something decide to block up when it was a sealed opperating system--arggg

[James Deuce]

yea but what would make something decide to block up when it was a sealed opperating system--arggg

Going from DOT 4 to DOT 5 without flushing properly will do that.

[jim.cox]

yea but what would make something decide to block up when it was a sealed opperating system--arggg

I've had this on my Quad (Polaris)

Only solution was to replace all the lines

I've wondered what caused it, as the lines were ok (warrantable) on the outside

[imdying]

yea but what would make something decide to block up when it was a sealed opperating system--arggg

Typically contamination from dirt, rusting cylinder bores, or incorrect fluid.

Going from DOT 4 to DOT 5 without flushing properly will do that.

Possible, but unlikely. DOT 5 is not actually easy to buy if you're not specifically looking for it. Much more likely is ATF, not unusual for some numpty to fill their brakes with that.

[mouldy]

yea but what would make something decide to block up when it was a sealed opperating system--arggg

Old age and moisture , same things happening to my body .

[Hinny]

Old age and moisture , same things happening to my body .

Old age and alcohol, same thing happening to my body.
Maybe somebody used something to liberate an 'oh' here or there to produce an alcohol from a hydrocarbon ??????????
Feck it's been a while since I knew any biochemistry.
I do know about the first part tho'!

[Hinny]

This Red is Sublime!