Rear Brake Issue

[jfarr53]

I have a Gen 1, 1989 Venture that has some ongoing problems with the rear brake. When I bought the bike, I noticed the rear brake pedal was very soft and about bottoming out. I removed the rear saddlebag to discover that the seals were blown out of the caliper. Bought the seals, rebuilt the caliper and thought everything was fine. Used the recommended fluid.

 

Was very careful not to overfill the reservoir. I was out riding at the end of the season when the bike started lugging. I came to a stop light and to my amazement the bike wouldn't move. I managed to get it to the side of the road and called my wife to bring the trailer. No fluid on the ground, no issues other than I could detect heat coming from the rear brake area. Brake pedal hard as a rock.

 

I tried to move the bike until my wife got there, no luck and while I was deciding what to do, - for some reason - pulled up on the foot brake pedal and voila - the brake instantly released! Brought the bike home and re bled the rear and front linked brake.

 

I has happened twice more with the same result. Give it a few minutes and pull up on the brake pedal and the bike frees up. What is concerning is the wear and tear on the brake, clutch and drive train from the brake slowly tightening as I drive.

 

Would you figure the master cylinder is suspect?

 

Thanks

Jim

[jfarr53]

Want to make it clear - carefully checked the fluid level and it is not overfilled!

[93 venture]

I had this happen to mine after i adjusted the link at the rear master cylinder, i was trying to make the master cylinder come on faster but it back fired and i ended up on the side of the road with locked up brakes,so i backed off the adjustment and it worked fine from there on.Im not talking about the petal height adjustment,but the adjustment close to the master cylinder.also make sure your linkage is not binding up on ya.

[skydoc_17]

Hey Jim,

Boy, I know just how you feel! Inside the master cylinder is a light spring that should retract the plunger but when the seals get old it gets stuck. I did mine and all was well. I think the rebuild kit is around $35.00 give or take a few bucks. You will also need a GOOD pair of snap ring pliers, I got a set at Sears. It's not to bad with the pliers, to take the master cylinder apart. Pay attention to the order things come out and you will be fine.

Earl

[bongobobny]

I would also recommend checking the bore of the cylander for scores or pits and hone if necessary...

[MiCarl]

I had this happen to mine after i adjusted the link at the rear master cylinder, i was trying to make the master cylinder come on faster but it back fired and i ended up on the side of the road with locked up brakes,so i backed off the adjustment and it worked fine from there on.Im not talking about the petal height adjustment,but the adjustment close to the master cylinder.

 

Put me down for doing this too. The pads rub just a little bit and as they get hotter and expand everything comes to a halt. After they cool down it rolls again.

[GeorgeS]

The Heat from Rear Exhaust pipe, heats the fluid in the Master, It Expands,

and applies the Brakes --- ( yes it does )

 

Fix, leave at least 1/2 inch of space for expansion when you fill the rear Master cylinder.

 

This is a common problem and been discussed many times.

[CrazyHorse]

So you are pulling up on the pedal? Theres a spring that makes the pedal return could that be broken?

[timgray]

I used to have to pull up on the pedal as well until I fixed the problem in the pedal linkage.

 

You need to disassemble the brake pedal and separate where it connects to the master cyl.

 

I drove the shaft out of the frame where it goes through, sanded it smooth, cleaned out the bushing where it went through and then reassembled (take the pipes off to make this easier) now the brake pedal moves like it is on new bearings, and I could not lift on the pedal if I wanted to it's resting point is all the way up. This eliminated a lot of my brake problems. There was junk in the bearing sleeve where the brake pedal shaft goes through the frame causing it to bind up and not return to the top like it is supposed to.

 

I can take pictures tonight to better explain it.

[rhncue]

I used to have to pull up on the pedal as well until I fixed the problem in the pedal linkage.

 

You need to disassemble the brake pedal and separate where it connects to the master cyl.

 

I drove the shaft out of the frame where it goes through, sanded it smooth, cleaned out the bushing where it went through and then reassembled (take the pipes off to make this easier) now the brake pedal moves like it is on new bearings, and I could not lift on the pedal if I wanted to it's resting point is all the way up. This eliminated a lot of my brake problems. There was junk in the bearing sleeve where the brake pedal shaft goes through the frame causing it to bind up and not return to the top like it is supposed to.

 

I can take pictures tonight to better explain it.

 

This is exactly the problem. If it were any other, lifting the pedal would not correct the problem. The spring on the back only has so much pressure and once the bushing and pin get rust then there is way to much friction for the spring to bring the pedal back to it's released state. Mine does this every spring from sitting out in the weather all winter. Every year I say I'm going to drill and install a grease fitting so that it won't happen again but when it occurs I'm always in a hurry to go riding.

 

Dick

[Venturous Randy]

This is exactly the problem. If it were any other, lifting the pedal would not correct the problem. The spring on the back only has so much pressure and once the bushing and pin get rust then there is way to much friction for the spring to bring the pedal back to it's released state. Mine does this every spring from sitting out in the weather all winter. Every year I say I'm going to drill and install a grease fitting so that it won't happen again but when it occurs I'm always in a hurry to go riding.

 

Dick

 

Ditto, the plunger in the master cylinder has to be up so the bleed orifice is effective. If the pedal is allowing the plunger to not return to it's seat, it will block flow back to the reservoir. As already stated, check the brake pedal movement first and it may solve your problem.

RandyA

Edited February 10, 2009 by Venturous Randy

[RedRocket]

The Heat from Rear Exhaust pipe, heats the fluid in the Master, It Expands,

and applies the Brakes --- ( yes it does )

 

Fix, leave at least 1/2 inch of space for expansion when you fill the rear Master cylinder.

 

This is a common problem and been discussed many times.

 

 

Being brand new with this bike, my rear brake reservoir looks to be pretty inacessible, with the lid being hard to remove. I can see that 'fill-hole' is pretty useful. How do I gauge it and not overfill it?

 

Thanks.

[jasonm.]

I used to have to pull up on the pedal as well until I fixed the problem in the pedal linkage.

 

You need to disassemble the brake pedal and separate where it connects to the master cyl.

 

I drove the shaft out of the frame where it goes through, sanded it smooth, cleaned out the bushing where it went through and then reassembled (take the pipes off to make this easier) now the brake pedal moves like it is on new bearings, and I could not lift on the pedal if I wanted to it's resting point is all the way up. This eliminated a lot of my brake problems. There was junk in the bearing sleeve where the brake pedal shaft goes through the frame causing it to bind up and not return to the top like it is supposed to.

 

I can take pictures tonight to better explain it.

 

A few shots of WD40 then fallowed w/PJ1 black chain lube may do the same as above. As I always lube all pivots and this is one of them.

[jfarr53]

Thanks for all the tips guys. Got a Hot Dawg heater installed in the garage a week or so ago and now have a toasty place to work. The priority for this weekend is to take the suggestions and act on them. I will let you know how I make out.

 

Otherwise - what a great ride. My wife likes it better than my old 1200 Wing.

[jfarr53]

To Redrocket:

 

be very careful with the 12MM bolt on the top of the reservoir. Mine was a little tight and I gave it a good pull and cracked the reservoir. Took me a couple of weeks to find another one. Yamaha said it wasn't available any longer so I had to wait for one to come up on eBay.

[Riceburner30281]

Need a rebuilt or a kit (seals) for a 1983 venture rear brake caliper.. even a new one if possible..

 

Can somebody post up a link??

[Rocket]

Need a rebuilt or a kit (seals) for a 1983 venture rear brake caliper.. even a new one if possible..

 

Can somebody post up a link??

 

Flatout Motorcycles (great to deal with) & put in that you are a member here in the comments box.

 

http://flatoutmotorcycles.com/fiche_section_detail.asp?category=Motorcycles&make=Yamaha&year=1983&fveh=4522

[Riceburner30281]

thanks! I actually needed the master cylinder kit, which I found for 52.85 +