81 maxim front brake issues

was nice today and thought i would take her out. while backing down the ramp noticed the front brakes wasn't working. the lever seems weak and has no pressure at all. took the line off and inspected for cracks , but found nothing. and also found very little fluid coming out. gonna try to get the screws out of master cylinder and see whats going on. any1 have an idea of what else to check ??? thanks

 

How long ago was the master and caliper rebuilt? How old are the brake lines?

I believe the rubber brake lines are supposed to be replaced every couple years. The caliper and master are due a rebuilt at the same time.

Upgrade to the stainless lines while you're in there. Makes a huge difference.

 

ok will do ... bad thing is i cant get the screws out of the MC. may try to find another on ebay. and i will also try to find a stainless line thanks

 

Xj4ever, upper right can help with both. An ebay master should still be rebuilt. Xj4ever has both the kits and new complete masters. As well as the stainless lines.

 

If you take the master cylinder to any machine shop they can remove the screws for you by drilling off the heads, taking off the lid and grabbing what's left of the screw in a vice. It's pretty straightforward and will save your cylinder.

 

As should your caliper. Original brake components will cause problems as soon as you start trying to rely on them regularly. NONE of the components' rubber seals were designed to last 30 years; neither were the pads and shoes. Master cylinder rebuild, caliper rebuild, pads and lines, and new shoes in the rear. Nothing less.

 

Put a bit of Kroil on them and let sit overnight ... then with all of your body weight pressed down through the screw driver, slowly break the sieze ... The key is a lot of pressure Down the screw driver - You need more pressure down than applied counterclock wise -- don't let up while balancing and slowly turning ... controlled constant weight on the screw driver - might have to take the MC off the bars ... However let the Kroil work for a long time

 

+1

But it is expensive -- do it perhaps in stages -- caliper - line - MC

 

Doing it in "stages" means having to bleed the system more than once.

Maybe "buy the parts in stages" but personally I'd rather bleed an empty system once just because it's so much fun.

The bottom line is it needs to be a complete rebuild. Do just the M/C and the caliper will start hanging up. Do only the caliper and the M/C will misbehave. Old pads crumble; old lines can pop at the worst moment.

It's not expensive at all compared to a hospital bill.

 

+1

My doctor won't even tell me there's nothing wrong with me for $150, the complete rebuild isn't really that expensive.

 

I bought all of my parts in stages! Now I just need to get it done. I'm doing all of the brakes, my starter and alternator, and then I should be set for a while again. I went with the S/S lines. Those things are a piece of artwork literally!

I'm undecided about the aftermarket drilled replacement rotor vs the OEM rotor. For $200.00 is it really an improvement if you are driving at normal hiway speeds or slightly above??? Feedback please!!!

 

Who did the drilling? Poor drilling can cause cracking. These rotors are fairly thin to begin with.

I've used drilled and slotted rotors on cars before. It's a decent difference. The pads generate gases between them and the rotor surface as they're applied. The holes, slots and dimples, depending on your style, remove these gases.

 

I believe it's EBC that offers the black replacement drilled rotor. Pricey,any benefits for normal driving vs my oem rotor?

 

They should stop shorter and keep your brake pads cooler. How much that matters depends on how agressively you're on the front brakes.

 

EBC offers replacement rotors, but the hub comes in "natural" if you want it black (like mine) you'll need to carefully mask and paint it.

They're only "pricey" until compared to the cost of a new OEM Yamaha rotor (nearly double.)

Drilling the stock rotor will help alleviate "fading" caused by multiple hard stops from freeway speed; the EBC brake doesn't know the meaning of "fade."

STAINLESS LINES make the single biggest difference though.

Stock rotor, (professionally) drilled, stainless lines:




EBC Rotor w/painted hub, EBC pads, stainless lines:

 

My OEM rotor is in really good shape. Maybe I should just have it drilled instead of replacing. Where did you send yours to get it drilled BigFitz? I have the S/S brake lines, and EBC brake pads, Master over haul kit, still need the wheel cylinder kit. So basically the same set up as you have. Or do I even need to drill it at all with the EBC brakes?

 

The only reason I drilled my stock rotor was that with SS lines and new Yamaha pads, the brake would fade severely enough after say, three 80mph-zero hard freeway stops in a row to be kind of scary on the fourth, as in lever to the bar and still not stopping quickly enough.

I haven't tried the EBC pads on a Yamaha rotor; drilled or un-drilled. I used EBC pads with the EBC rotor, and Yamaha pads with the Yamaha rotor, so I can't really tell you how well the EBC pads will perform with the Yamaha rotor.

I would say try it and see how the EBC pads perform for you with a stock Yamaha rotor; if you don't experience any fading or other issues to justify drilling, don't.

I sent my rotor out to an automotive hi-performance brake guy to get drilled; I'll have to see if I can dig up the info.

 

Thank You.
With that, I will report back and let you know how it all works out. That may not be until May though!!!