83 rear brake stuck, re-built both MC and caliper, what next?

[bongobobny]

YCIS? What is that? Is that the mythical Twinkie?

 

RR

No, the YICS sets above the "twinkie." It is a plastic tank with 4 vacuum lines coming to it, one for each cylinder. How it works is it smooths out or equalizes the vacuum, sort of...

[GoldenRider]

Ah, I think my YICS was removed by the PO. Now I just have a crankcase breather filter on top of the twinkie. I plan on running a hose up to the air box instead of using this filter though. I read this was how the twinkie (give or take a YICS) was supposed to be set up. Pretty sure a lot of my oil leaks are coming out of that breather from my over-fillings and subsequent eruptions of oil when pressure builds.

 

Onto the oil leaks though, I've been dealing with some leaks for a while. First it was at the base of the carb boots. I replaced those and rtved where they sit on the engine. No leaks there anymore. Now, as indicated by lots of carb cleaner, it seems like it's the base of the twinkie that has a leak. I've ordered the gaskets already, hopefully that's the last of my leaks. Does anyone know if it would be beneficial for me to try and get a YICS to install on my bike? Pretty sure I saw a couple for sale when I was searching for twinkie gaskets.

[GoldenRider]

Oh I just realized I never mentioned my engine was an 86 since this was originally a just a post about brakes. I just read that the YICS wasn't needed on the 1300s.

[bongobobny]

Ahhh, that changes things! I went by the title of the thread thinking you had an '83! As far as the YICS, as I mentioned it was a feature that worked better on paper than in reality, and so to reduce manufacturing costs, it was eliminated on the MK2. Good old cheaper, better, faster...

 

Yup, any more oil than halfway up the site glass will get thrown out as blowby! With the carb boots, did you replace the base "O" rings and clean the mating surfaces?? There should have been no need for using RTV, but hey, if it fixed your vacuum leak there so be it! Your twinkie acts as an oil cooler so yes it can indeed develop oil leaks!