Beat by rubber hose?

Trixie Combat, as usual has been a couple 3 steps forward for 1 or 2 backwards. Two issues remain on front brake one a leak nuisance the other dang dangerous. Symptoms are no ability to lock up as a few year prior and ongoing decrease in wheel slowing the longer I use it and the Harder I Grip IT! Ridiculous that lighter initial pressure gives good sense of slowing power then just fades away as I escalate up to panic grip. Last time could not even stop roll at walking speed in garage. ugh.
A clue I'm following up on is the fluid is showing a black dust like sediment in the reservoir I'd not seen years prior. I held hose while levering to feel it swell a bit in its middle section but not nearer the ends. I now suspect just need another $60 hose to have a decent factory brake again. Its '72 Vintage so what do I expect, economy forever on parts not already renewed once or twice. ugh. Hope that's it.

Leak at lever is not from pressure as no amount of pumping, holding effects it, just time to weep drip by drip, was sealed during Empire rally period but that close to Peel traveling must of pissed her off. I almost discovered this the hard way having fine brake a day prior to going free fall down driveway Gravel slope.

OH yeah another thing may learn from me the easy way, I use RH mirror stalk as lever pivot and if ya get it too tight it binds brake lever from full return forward so rather lessens the brake action that way too. Ugh.

I had similar symptoms with my front brake last year, including fluid weeping from the lever bellows, but there were no black particles in the fluid. I was ready to remove and relace all brake components, then I had another look at the cap on the master cylinder resevoir. That tiny breather hole was plugged up. I cleaned out a solid congealed mass of old wax and dust. I replaced the cap and right away noticed less hand presssure was required to lever the brake, a few more pumps then a test ride, and the front brake was repaired like magic. The fluid leak also stopped right away, and there have been no leaks or brake fade for over a year now. I recall you ride on some gravel roads, so I suggest you clean out that cap's pressure relief hole...it may work for you.

By George singing, I think you might of caught what I'd over looked, ugh, I'd clear coated the fill cap and noticed it congealed on top, likely blocking the vent in our pressurizing heat wave. Will take the lid off and watch for drips while awaiting new $85 factory hose and $130 set of peashooters. I've resleeved m/c that worked a treat on Peel, but it ain't got a Norton part number so it don't fit Trixie's needs or my need to have a true baseline Combat to know what you'al are missing out on with the likes of tri-linked Un-Norton Ms Peel.

The sediment is on scale of brewed coffee stain particles, either from the lid seal, hose or both. I've had about every other type brake let down, but prior I always got a bit better braking the more panic grip on lever, but not this time around, more panic grip gave suddenly less relief! Not what you want to feel slowing down hill into a sharp Gravel turn and engine won't return to below 3000 rpm.
My ABS cars are like this on THE Gravel, just when you think the car will stop like on tarmac the sensors sense the wheels locking up and releases brake to coast over a car length beyond intended stop spot. Last bit of stopping on THE Grit requires a bit of wheel lock slide to pile up resistance last couple mph. If bike fork turned the tiniest bit off dead ahead, SPLAT before you know what happened.

Anodized slides on the way to hope bores not beat up as bad as slides too.

Well I think the cap vent was clogged but got it open for light to shine through, but prior I"d left the cap total loose laying on rubber bellows and it increased the leak several times for a palm size puddle over night instead of a dozen drips, ugh. Nothing for it but dive back in and see what's too corroded to seal and spend spend spend some more more more...

If you are going to spend $80 on a brake hose why not just go with a braided stainless steel for the peace of mind factor? I rebuilt my old MC and caliper and put a SS on and works great (as original will work that is, need to do the sleeving)!

I destroyed my last real Combat Ms Peel, though I wouldn't of done anything different except buy a rev limiter for Boyer. Peel had all the after market stuff available a decade ago. To make amends i bought Trixie who only gets parts with a number in the good book. I know how good a plain Jane factory only Combat can be so just want to have the best baseline example I can. Its been a test not to just to stay ahead of the ongoing decay. I'd already been through her brakes in '06 when deer strike took out everything you can label as RH side components forks to muffler.
Mufflers were good to go until this year, so another expense this week. Carb worked great super slow 400 rpm idle return, till this year first break in. Anodized slides on the way. So I'm only half fast practical purist, but know the front brake ain't that bad once up to snuff. Leaks out tach drive even with PCV and my make shift seals. Parts boxes are flowing in weekly and ain't bought nothing for my real favorite gal in a while. But daily progress made on her too, just not decaying yet.