Rear Brake Master Cylinder Part

Hello,

I recently had a little incident where my TE449 spit some gas out of the overflow tube and it managed to light on fire. Anyways unfortunately I melted the plastic sight glass on the rear brake cylinder/pump(right behind the brake pedal). It now leaks brake oil from the sight glass. The parts manual doesn't show the sight glass as being an available part. I would rather not have to buy a complete rear brake assembly for one piece.

you're gonna hafta go with a used master cylinder or epoxy the sight glass. hell, change your brake fluid once a year and you won't need a sight glass. btw, the reservoir is for brake pad wear. some people believe it's to give you brakes when you develop a leak.

I think someone makes/made a Brembo master cyl lid with a hose fitting & no vent holes; so you could mount a remote reservoir above it.

good luck.

edit: "overflow tube"... are you talking about the vent hose? make sure it runs from the tank filler all the way to the front of the bike (and goes above the tank level). The steering stem hole is the traditional place to route it.

Overflow might be caused by putting (cool) fuel in your bike and filling it up to the neck. when the fuel reaches ambient tempature, it will expand (and the vapor pressure increases also) pushing the fuel up & out. Put about an inch less fuel in, if you're not riding right away.

I had removed the Evap canister and rerouted the hose down by the rear shock. Had been like that for a couple years now. There is a little valve in the vent hose. That little valve makes moaning noises when the bike gets hot.

I had been riding for over an hour by the time it happened. The gas level couldn't have been super high. Either way I will reroute the vent hose elsewhere.

Vent hose routing-
Your exhaust (and possibly catalytic converter) is in that area. your little fire is god's way of saying: pay attention here- don't do that or something big could go wrong. your plan to reroute is the right thing to do.

the one-way valve (it might be a 2-way valve; seriously) is part of the vapor recovery system- which you don't have anymore. remove it. believe or not, modern vehicle fuel tanks are actually under a minor vacuum for the Evaporative (vapor) recovery system. they vent at both excess over- and under-pressure in the rare event they have to. That's the sound you heard probably. your system should be at atmospheric pressure- and add some hose to run it up to the front of the bike (and make go higher than the tank or at least put a loop in it- to keep the liquid gas in). look where your vent is at on the rear filler (low); most bikes are vented through the cap (highest point).

to sum up:

• gas tanks need to breath in AND out. both ways.
• liquid gas outside the tank: bad. (and outside the tank near a 1000° metal surface: in-fukken-sane)
• you had a fire- that is NOT normal at all and needs to be fixed. you've been lucky for a year or so.
• your sight glass is a symptom of the above issues. clean it with brake cleaner, epoxy it up- should be fine.
• your plan to reroute the vent line to address all these issues is the smart thing to do.

Okay So I have the vent line off. The check valve is a bit of a strange gadget. It allows air to move freely into the tank. When I blow into it (simulating positive tank pressure) it does release pressure but makes the moaning sound I was refering to.

Unfortunately there doesn't seem to be any good spots to run the line to the front of the bike. There isn't anywhere under the seat it will physically fit.

well, it ran to the vapor cannister before; wasn't that up front?

I think my son's vent hose is running along the right subframe toprail, and then alongside the frame backbone (above the forward-mounted airfilter). t'aint rocket surgery.

good luck.

ps- I've been biting my lip, trying not take the bait... but anymore more setups like: "...makes moaning noises when the bike gets hot" or "When I blow it makes the moaning sound..." and I'm gonna hafta start making comparisons to my first ex-wife.

Well at least your ex-wife didn't almost kill you with gasoline.Actually I don't know that maybe she did.

Yeah I was overthinking it a little. There was room where you described (allthough it does provide a little interference). Thinner fuel line would have been nice. I ended up running it into the steering stem hole. Seems to be fine there.

I used JB weld and epoxied the hell out of the sight glass. It seems to be holding fine. I am hoping the JB weld can hold up to the corrosive nature of brake fluid. Time will tell.

Thanks for the help, You guys are awesome.

yeah, traditional vent line (3/16" IIRC) is more flexible and supple than fuel hose. Vacuum hose and radiator overflow hose are good substitutes. I put an old jet in the far end just to reduce the inner diameter. I used to stick a piece of foam in there too, for an air filter. For some reason I quit doing that; with fuel injection I think I'm gonna start again.

Epoxy- brake fluid shouldn't be a problem at all. I hope you cleaned it well beforehand (brake cleaner). didja leave a little tiny clear window?

congrats.

I ran across this guy on ebay who "rebuilds" the master cylinder sight glass:

http://www.ebay.com/itm/NEW-SITE-GLASS-MOTORCYCLE-Clutch-Brake-MASTER-CYLINDER-/370418875615?item=370418875615&pt=Motorcycles_Parts_Accessories&vxp=mtr&nma=true&si=EB2x2HHQ8qQGJ1gZPxVkwVh3bIA%3D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557


he also sells thermistors for low-fuel senders:

http://www.ebay.com/itm/REPAIR-Your...m33b882d792:m:mfAUDuoXHjGWjaHSxj6quOQ&vxp=mtr

Hi Trenchcoat,

are you sure, that the one way checker valve is only functioning for the evap system?
I am asking because my European '13 TE449 has never had an evap system but is equipped with the valve. Afterwards the hose is routed down to the linkage.

Best regards,
Florian

Hi Florian-

No, I am not sure about the one-way valve. But also I think it's a two-way valve. if so, this would be in and of itself a small vapor control system. but I am surprised to hear the euro version doesn't have the charcoal canister to hold the vapors also.

Try sucking through the vent tube- should be easy. Now try blowing through it- there should be some resistance before you can feel air moving. (Also, be careful of liquid gas in the system)

A tank with a one-way valve on the vent is in danger of splitting under positive pressure (under fairly common conditions).

edit: The TCs come with this valve too. I couldn't figure out why until I realized that any liquid gas that got in the vent would be held there.... for a little bit, at least (guessing). If any positive pressure built up (eg. stopping after a hard ride; fuel heating up) it'd be blown right out of there. Or continue riding and the teaspoon of fuel (5ml for our euro friends) would probably get sucked back in eventually. Anyways, with 449/511s tank placement, venting is an issue to keep an eye on.