Cleaning and Bleeding Brakes

You're going to discover the rebuild kits for the calipers are a minor fortune, and they do no include the "o" rings for the left and right halves...

You're going to discover the rebuild kits for the calipers are a minor fortune, and they do no include the "o" rings for the left and right halves...

Yes, they just pop out, and yes, that's what I was referring to, the kits are just the rubber seals and assembly grease, and the kits are per side, or in other words, you need 2 kits per caliper at around $25 per kit...

Yes, they just pop out, and yes, that's what I was referring to, the kits are just the rubber seals and assembly grease, and the kits are per side, or in other words, you need 2 kits per caliper at around $25 per kit...

I've been dealing with sticky pistons on all three calipers and have spent way too many hours cleaning them by sliding them in and out so I figure popping the pistons is probably what should be done now.

Do you know if the O-rings are special and are they available in sets?

Well, at the time, several years ago now, the only ones I could find were OEM's. No, nothing really fancy about them, they are just flat rubber band type o-rings or seals, whichever you prefer to call them. I would strongly recommend you hone the cylinders while they are disassembled and make sure your o-ring grooves are meticulously cleaned to avoid any possible leakage. Try very hard not to put any gouges in the groves as that is the number one cause of leaking seals! Use a good amount of that red "grease" that they supply with the seals to also aid in proper sealing. The last thing I will recommend is to polish the pistons as best as possible, I actually used my buffing wheel for the final finish. If you plan on using an abrasive on the pistons, make sure the scratches go around the circumference of the piston, and not front to back which would give the hydraulic fluid a direct path to flow from inside the caliper to the outside world. I usually chemically soak mine followed by an ultrasonic bath and then the buffer, the smoother the surface, the better...

You might want to try Earl for the kits, he is a great guy to deal with! Othe sources may be boats.net or partzilla. I was lucky with a couple of kits and found them on ebay for a good price, but you have to literally watch daily for a month or two sometimes...

I would strongly recommend you hone the cylinders while they are disassembled and make sure your o-ring grooves are meticulously cleaned to avoid any possible leakage. Try very hard not to put any gouges in the grooves as that is the number one cause of leaking seals! Use a good amount of that red "grease" that they supply with the seals to also aid in proper sealing. The last thing I will recommend is to polish the pistons as best as possible, I actually used my buffing wheel for the final finish. If you plan on using an abrasive on the pistons, make sure the scratches go around the circumference of the piston, and not front to back which would give the hydraulic fluid a direct path to flow from inside the caliper to the outside world. I usually chemically soak mine followed by an ultrasonic bath and then the buffer, the smoother the surface, the better...

 

You might want to try Earl for the kits, he is a great guy to deal with! Othe sources may be boats.net or partzilla. I was lucky with a couple of kits and found them on ebay for a good price, but you have to literally watch daily for a month or two sometimes...

So I just updated my post on Cleaning and Bleeding Brakes to include the cleaning part of the process. Popping the pistons out is pretty straight forward and just takes time, most of which was spent in getting the pistons back in. There was nothing unexpected that happened so all my stressing and delaying getting to it was unnecessary.

I did not replace the o-rings, just cleaned them with my special toothbrush and some brake clean.

If you have a hydraulic shop near you look there for o-rings. I rebuild cylinders now and then on some of my equipment and have found buying them separate instead of a kit saves a bunch of cash. Take your parts and they can mic them to gets perfect fit. The shop I deal with stocks a ton of sizes and types, the last ones I got for a brake cylinder cost a couple bucks.

If you have a hydraulic shop near you look there for o-rings. I rebuild cylinders now and then on some of my equipment and have found buying them separate instead of a kit saves a bunch of cash. Take your parts and they can mic them to gets perfect fit. The shop I deal with stocks a ton of sizes and types, the last ones I got for a brake cylinder cost a couple bucks.

A while before attempting this job I looked into getting the O-ring kits from the local Yamaha dealer although I don't recall how much the cost was they were extremely expensive. I could get the same Yamaha kit in from the USA for $50 less but that was still on the expensive side.

Thanks for the idea.

That's a really good idea, particularly for us Canadians.

 

A while before attempting this job I looked into getting the O-ring kits from the local Yamaha dealer although I don't recall how much the cost was they were extremely expensive. I could get the same Yamaha kit in from the USA for $50 less but that was still on the expensive side.

 

Thanks for the idea.

Just make sure they know it's for brakes to get the right type of rubber. Some rings don't like brake fluid. Like I said the shop I go to has a huge stock, kits for some of my bigger cylinders cost $200-250 but I get them apart and take in the parts to get them sized and just buy what I need for around $40. These are 6" diameter rams 6' long.

Just make sure they know it's for brakes to get the right type of rubber. Some rings don't like brake fluid. Like I said the shop I go to has a huge stock, kits for some of my bigger cylinders cost $200-250 but I get them apart and take in the parts to get them sized and just buy what I need for around $40. These are 6" diameter rams 6' long.

Have you purchased O-ring seals and scrapers for Yamaha brakes? If so, do you happen to have part numbers?

Sorry I don't have part numbers. I know I've bought for Honda there but i don't remember ever having to rebuild any of my Venture calipers. I take the parts in and they mic the piston and bore, go to the shelf, and bring me seals. They usually even install the seals.

PM Earl, Skydoc_17, he might have some info or buy from him, I'm pretty sure he has them in stock...

Sorry I don't have part numbers. I know I've bought for Honda there but i don't remember ever having to rebuild any of my Venture calipers. I take the parts in and they mic the piston and bore, go to the shelf, and bring me seals. They usually even install the seals.

Thanks.

PM Earl, Skydoc_17, he might have some info or buy from him, I'm pretty sure he has them in stock...

Earl usually has a good supply of oddball items. Getting things across the border is a bit of a pain so sourcing locally if possible is my preferred method.