BARE Min you should do/replace if swapping MCs??

So assuming:

You acquire a replacement OEM MC that does not absolutely need a rebuild kit (yet) and you DON'T have the fund$ at the moment to do a full SS/pad/rebuild upgrade....

What is the bare minimum in parts/labor you should do swapping out a working aftermarket MC with an Ebay acquired OEM MC?

I.E. Flush/bleed lines, change banjos, etc? I've never really done this. I know I should do it proper for my own safety but I'm just curious. (I'm also waiting on the MC to arrive and a full blown upgrade quote from Chacal).

NOTE: I probably won't do the bare minimum but I'd still like to know, unadvised or not :wink:

 

Going on a buget, all you need to buy is brake fluid. Banjo bolts and washers can be re-used several times with no problems. I would take the new MC apart to make sure there is no crud inside. Be careful not to damage the old seals, they are old but most likley still good. Clean all the inside parts and clean all the little bleed hole in there. I do it all the time to get a project rolling, but will always do a proper rebuild as soon as funds are available. A MC kit is cheap 25$ or so.

 

Don't reuse the banjo crush washers, that's asking for trouble.

New fluid of course; NEW banjo bolt crush washers; ensure that the openings in the banjo bolts are clear and clean, including the bore.

I wouldn't trust my life to the eBay part without a rebuild.

 

Well MC rebuild and banjo bolts I probably can afford
SS Lines probably not for a while...

 

The thing with SS lines is you have to replace the brake lines anyway, and the difference between the stock rubber and SS is not all that great.

 

Yeah I know
But any brake lines (all 3) would be pricey atm...

 

Sorry, but I cannot agree with Bigfitz on this one!
Rubber lines expand under pressure, even when new - with the old ones on my GPZ900r, I could actually see it happening.
and by "ss" I assume you mean stainless steel (braided) - being nylon these do not.

 

No arguments there.

But we been chatting about prices and my limited budget atm, no quality of the types of lines

When I upgrade - SS all the way

 

There have been a fair number of folks who have made the switch to ss lines and report a marked difference in braking improvement. Fitz, have you had a different experience?
For the price, you are best served getting the ss lines. I'll recommend Chacal's as they are DOT approved materials (not sure if they are DOT approved assemblies, Chacal will provide guidance on this topic).

 

Wait a sec, here - you're swapping out a FUNCTIONING non-OEM master cylinder for an ebay 'original' master cylinder? That eliminates quite a few things. That is, you already KNOW your caliper, hoses, washers, etc. are good (or, good enough that you're willling to ride it).

Fluid only. And if you're REALLY cheap, don't "bump" the lines, leave 'em full during the actual master cylinder swap and you'll only have a minimum of bleeding to do (after all, the system is ALREADY working...)

+1 (with mlew) on the reuse of washers. They won't fail catastrophically. They'll weep obviously and quite awhile first. Keep an eye on 'em, of course. Still, how much are new copper or aluminum brake washers from a cheapie auto parts store - a couple bucks? And you only need the two at the master cylinder...

+1 on the careful disassembly, clean (incl. pinhole) and reassembly of the ebay master cylinder first. Go slow, take your time, don't rip or tear anything. After all, the bike is still on the road at this point. No need to hurry the refurb of the ebay part. When you're ready to swap, the bike will only need to be out of commission for an hour or two...

Good luck,

Kirk

 

I believe he means cost wise...

 

Yes sorta.

I'm eventually going to swap a working aftermarket MC out for an oem (i think) MC assembly.

By assembly I mean: MC, handle, brake light switch and fluid level sensor.
Currently I don't have either the switch or the sensor on the "working" MC. This is why I snatched up a CHEAP ebay find when I saw it.

I'm going to post pics of the Ebay item shortly, and hopefully experts can help me determine if it actually came off a 750 maxim original or just some random yamaha. (It has the RH threads, and the yamaha switch and sensor - but replacement lid).

BTW the inside is NOT clean. So I will get the rebuild and new lines and maybe more when I do swap the MC. I can live w/o the brake light switch for a while longer (I do have a working rear brake switch).

 

Yes, the brake lines we sell (both the original rubber style and the performance braided s/s versions) are completely DOT approved complete assemblies. Almost all companies the make brake lines use DOT-approved component pieces, but just having the component pieces being DOT-approved does NOT make the final assembly DOT-approved. That level of approval requires pressure and other testing of each individual line, which is why most shops don't do it......

 

You have to ask yourself this question

"What is your safety and life worth?"

If it were me I'd park it before I would risk my safety on old brake parts.

Rebuild your brakes, make it safe.

my 2 cents

MN

 

Nope, that argument don't hold water. If it did, no one drive a vintage bike with drum brakes, or YOU wouldn't drive your OWN bike until you had upgraded it with the best setup off some hyper-sports bike.

I mean, using that 'what is your life worth' argument, you'd heve to logically say that in an extreme emergency, the reduction of 3 feet of stopping distance the R1 system provides might make the difference between life and death, so you'd better park your ol' Maxim 750 until you've fully upgraded to the best money can buy. After all, what's your life worth...

I mean, I'm not talking about riding around with sticky brakes, or NO front brake system, etc. but that "what's your life worth, after all" argument is NOT what "you have to ask yourself" because it has no logical stopping point. One MUST be driven right to the extreme - best brakes, best tires, best, best, best....

Just MY two cents.



Kirk

 

Well this discussion may go on for a while and I won't be aiming for any minimal shortcuts.

So I'll move my questions bout my ebay purchase to a new topic once I can upload the pics. Thanks for the info though

 

Since the front brakes are over 70% of the stopping power of these bikes I will say that It would be best to rebuild the master cylinder and make the system as safe as it was intended to be. Nothing more or less.
Becides did I say anything about going overboard about upgrading the brake system to an R1 or anything like that.

Kirk If you want to bolt on some unknown condition brake part on your bike go ahead and do it.

The author of this thread was looking for opinions, not for you to get on another members case and blow up out of porportion.

Just so you know Kirk, I do feel that my life & any other member's is worth more then a few 30 year old rubber hoses and seals that don't amount to much.

MN

 

Oh, for heaven's sake... No one took that position.

He asked opinions on the minimum to do. Originally, no mention was made of the condition of any of the rest of the system. Only recommended work related to the master cylinder swap.

Some opined that a full upgrade was the minimum - stainless lines, upgrade pads, etc etc.

Others opined (including me) that rebuilding the ebay master cylinder was the minimum.

He didn't say he was thinking of bolting on the part in condition-unknown and no one recommended he do so.

I agree 100% with your 'revised' post - make it as safe as the system was originally.

I'm sorry, but that "what is your life worth" line of logic is just one of those things that pushes my buttons...

 

No, but you DID ask the rhetorical question "you have to ask yourself..." The only logical answer to that is that one must go all the way, because no one would argue that your life is worth $50 of new rubber bits, but NOT worth $3000 worth of system upgrades.

...but NOT worth the "overboard" of upgrading to an R1 system? I think YOU'RE worth an R1 system...


Enough said. I apologize for overreacting and goin' off on you. That wasn't my intent at all and I was out of line. After all, I'm the newb here and haven't earned any respect yet, haven't 'earned my wings' so to speak.

Thanks for the input.

Kirk

 

YES, I did. The COST difference between the stock rubber and SS...

We were discussing budgetary constraints, I omitted the word "cost."

Stainless lines are FAR SUPERIOR to the stock Yamaha lines, even brand new stock lines. Highly recommended.