"Flash"ter cylinder

[xs11bobber]

Ok. So I have the 5/8" bore master cylinder. And I was going to get the 833 series Colorflex SS brake lines.

You think I'll be ok?

[fredintoon]

Ok. So I have the 5/8" bore master cylinder. And I was going to get the 833 series Colorflex SS brake lines. You think I'll be ok?

Hi Josh,
I have never put a reduced diameter M/C on an XS11 but, in theory anyway, the reduced line-swelling given by fitting S/S lines should tend towards balancing the increased softness of a 5/8" vs an 11/16" M/C.
Fitting the leftside caliper to an XS650 (North American XS650s only had the rightside caliper) effectively reduced the stock M/C piston area by 50% (as it was now working 2 calipers instead of 1) which turned the wooden feel into really soggy. Swapping the fabric lines for S/S lines turned soggy into perfect.

[TopCatGr58]

Hey Bobber,

I agree with Fred that you should be good with the 1/16" smaller bore MC!

My 81Sh MC was all crapped up, and I didn't have this site when I was doing my rebuild. I found an XJ11 MC, which is designed/sized to drive only 1 front caliper. It WAS spongy, even after repeated bleeding, and I had to pump the lever a couple of times before it would build up adequate pressure, but still had to squeeze the lever almost to the grip!

THEN I put on SS lines, and it was night and day, have plenty of braking power, only have to squeeze the lever once.
T.C.

[xs11bobber]

New Question...

I lost the auction on eBay previously stated on this post. I ended up going out of town and the master sold for $173!! Anyway, I just started searching again and came across something I wanted to check on with you guys here first.
The "OEM" replacement coils you buy are easier found on PartsNMore if you search for the GL1100. Well, thinking about this I wondered why the front master from the GL1100 wouldn't work perfectly. I believe it's a 7/8" bar size and a 14mm bore and was set up to run the dual calipers. Then I found one on the net that had been triple chromed, so now I'm interested.
Will this work/cause any problems?
As stated previously in this post I am going with the SS brake lines as well.

[fredintoon]

- - - it's a 7/8" bar size and a 14mm bore and was set up to run the dual calipers. Then I found one on the net that had been triple chromed, so now I'm interested.
Will this work/cause any problems?
As stated previously in this post I am going with the SS brake lines as well.

Hi Josh,
you will be swapping an 11/16" (17.46mm) bore m/c for one with a 14mm bore.
When comparing m/c bores it's the areas, not the diameters.
A 17.46mm seal has an area of 240 sq. mm.
A 14mm seal has an area of 154 sq. mm.
What does this mean when you swap them?
The smaller m/c takes only 0.64 of the effort to work the calipers but the piston has to travel 1.56 times as far to do it.
IMHO, even with the hardening effect of s/st lines you run a real risk of the brake lever hitting the twistgrip before the brakes are fully on.

[xs11bobber]

ok, so about the only way that's going to fly is if I were using the GL braking system. I'm about 98% sure it's not a bolt on and go type thing either so I'm gonna just forget that for now. I've been looking into local chromers in the area. A quote for just the stock clutch lever and perch was $45-$75 without a visual inspection. Maybe that's gonna be my route of lowest cost for the visual effect I'm going for. Because I have both, the front master just needs a rebuild. The only drawback is the once white, now brown resevoir and plastic cap. Hmmm...

Thanks for your help Fred.

[fredintoon]

Just for looks

- - - A quote for just the stock clutch lever and perch was $45-$75 without a visual inspection. Maybe that's gonna be my route of lowest cost for the visual effect I'm going for. Because I have both, the front master just needs a rebuild. The only drawback is the once white, now brown reservoir and plastic cap. Hmmm...

Hi Josh,
if the reservoir and cap work OK but simply look ugly, you could cover them up?
Make a close fitting snap-on reservoir cover from sheet steel and get it chromed too.
A raised Yamaha triple tuning fork emblem punched in from the underside of the cover would look real trick.

[xs11bobber]

Thread still alive...

So I bought this ebay master cyl.

You can see my question at the bottom of the page asking what bore it is. The 'person' replied with "standard 5/8" bore." Now correct me if I'm wrong, but the number stamped on nearly every 'new' master cyl. on the right side of the clamp in a mounted on bike position is the bore? I just opened it and it says 9/16." I'm guessing from previous posts that 1/8" smaller bore is going to be too spongy so I'm hopnig I'm wrong about the stamp being the bore, but then 9/16" doesn't quiet equal 1" as obviously stated under the bold title "for harley or custom" so it has to be the bore... damn

[DiverRay]

So he STATED it was for 1" bars, and you bid on it?????
I'm sorry, but you just didn't READ the response you had from the people who know their stuff! You now need a shim so it will fit the 7/8" bars, AND SS lines so it doesn't just slow you down a little......
It CAN work, it will just take a little more to make it so. Start at the local hardware store and buy a bit of shim stock. I like stainless steel, as it will not rust, nor will it react with the aluminum on the master cyl. The next need is the SS brake line. I would NOT try to stop with the stock rubber lines. You may end up in the garage wall, not in front of it!
The system WILL work, it will just take a little more to make it work. IF you only want a single front disk, it will probably work well, but you will NOT stop like the dual disks you now have. With the idiots that "guide" the cars now, you need all the brakes and power you can get to keep from getting killed, IMHO.

[xs11bobber]

So he STATED it was for 1" bars, and you bid on it?????
I'm sorry, but you just didn't READ the response you had from the people who know their stuff! You now need a shim so it will fit the 7/8" bars, AND SS lines so it doesn't just slow you down a little......

Someone else want to tack a whirl at this. Ray apparently didn't read or follow too closely. Seller stated it was a 5/8" bore which Fred and T.C. both agreed I'd be ok with. It arrived at my door step with a big 9/16" stamped on it which I assume is the bore. If 1/16" smaller will work ok with dual calipers, what is 1/8" going to do to me!?

I e-mailed seller and complained, but unless the 9/16" will work I'm gonna have to start looking again.

[xs11bobber]

How does a hydraulic brake light switch work like the one from MikesXS part# 29-7000? And where does it go?