Just took delivery of another Blue RC26!

3 months later I decided to get this one going, starting with the front brakes. Should only be the new battery and maybe/probably carb work after I get this done.

So far so good on the bake calipers. Hopefully pistons will pop out OK! Got some penetrate soaking in right now....

 

those look worse than mine?

 

Nothing I can't handle......

 

yeah, mine are definitely NOT working properly ?
they will close but then it just holds pressure and doesn't release??
cleaned them all up and tried them again on the bench with another master and still same result???

 

You should be able to move the pistons in and out with a little gentle pressure. If you can't, your problem may be with your seals or pistons themselves. Use some brake fluid as a lube to help things move....

 

I believe there is a small pin hole in the master cylinder that if not clean will prevent the pucks from releasing. Double check to make sure that hole is clear …


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I can squish them back in, and they seem smooth but then they just stay tight when you tighten them back up.

 

Thanks , six, but I have ruled out the master. I've tried two different ones and put a different set of calipers on the bike and they work great!

 

Gotcha …


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how do you open these things up to rebuild them anyway?
to get to the pistons??

 

If only you had one the service manuals that has more than just a story about Honda in it.

 

That.......plus Joe's V4 Dreams website - in particular his "Maintenance" page - and go to:

#23 • Brake Caliper Disassembly
and #2 • Rear Caliper Sleeve Replacement ('86-87)

https://v4dreams.com/maintenance.html

 

On nice, thanks guys!
I didn't think to look in the VFR manual, duh, !!
And I will check out Joes...

 

Calipers are fairly easy and we seem to all have a certain technique we like. I have since adopted using the normal brake system to pressure out the pistons. I was using air which made shit fly all over.. lol

 

And every time I forget to press them out while I still have a working (or kinda working) hydraulic system I'm pissed at myself. I undo the banjo and remove the caliper and then say, "Fuck. You idiot."

I will sometimes go outside and try air, but if they are nasty I don;t even bother anymore. I just hook them up to my pre-bled master I have just for doing this.

 

Air takes a distant second place to hydraulic fluid - mostly because air can compress but hydraulic fluid doesn't.

Capt 80's has a nice set up with a rear brake master and slave on a bench so just plumb up the hose and push......

I bought a rear brake assy. but have yet to get it set up. That setup is the cat's pajamas, for real!

 

Those pistons did not budge for me. Alas was just using air from a pancake portable compressor. I will give them more soaking and then take them over to my mechanic, who has a proper air compressor for situations like this.

In the meantime I pulled out a backup set of front calipers......and those pistons came out just fine. I used the Joe "V4 Dreams" Nelson technique of using wood paint stir sticks to control the carnage!

Now to give everything a good cleaning with my water based Purple Power Cleaner I get from Walmart.

 

Sonic bath will save you hours!! Do it, best $120 spent on shop equipment. Now that my shop has moved, I can make a permanent "brake station".

 

Thanks, Rogue....I have one but don't want to mess up the gold patina on the calipers. I use it for carbs though, for sure. And some other stuff.

Yeah my "shop" situation is the kitchen counter, tailgate on my truck, and a small table I have set up next to my lift table. And that's it for now.


When you do your brake caliper with your Sonic...what solution do you use, at what temp, and for how long? And are they like these gold ones on the RC26?



Thanks!

 

I used sink water, or distilled with carbs, Dove dish soap, and sometimes a spritz of floor cleaner. I try and keep it to just Dove. I keep the heat around 60*c I believe (moderate heat just a bit uncomfortable to put hands in) and 25-50 minutes depending on filth level. I have never lost any black or gold on my calipers. I will even soak an entire sealed set of calipers, pads, and brake line to remove old brake dust in difficult places. I have noticed staining on exposed aluminum at those heated temps, but no damage to factory paint as of yet.

Part of my regiment on rebuilds is to sandblast and vapor hone, so when I cleaned in between with heated sonic, it jacked up the raw even aluminum look. I just do a cold clean from now on, on raw aluminum parts and finalize with an isopropyl alcohol bath to prep for paint (usually VHT clear).