Braking up - is hard to do.

Getting your blazingly fast Suzuki powerplant to perform even better!

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tz375
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Braking up - is hard to do.

Post by tz375 »

I pulled out the front wheel of the Buffalo Phat Trakka project bike and dropped it carefully on the bathroom scales.

Including axle, sleeves and nuts but missing 4 disk bolts and tabs, it weighed in as the heavyweight champ at 36.6 pounds. :shock:
Pulled off the pair of disks but still with the axle and everything on that, it was a svelte 23.4 pounds. That includes tire and tube, so it's not too bad.

Still some room to get a few more ounces out of that.

Then I added back a single CBR600F4 disk and a 3mm spacer and 6 Yamaha disk cap screws and it was back up to 26.0 pounds.

That's 10 pounds lighter than stock right there on one wheel.

I'm hoping that one disk with SV650/EX500 type sliding 2 piston caliper will be more than enough brakes. kawasaki triple riders swear that a single stock low friction stainless disk and EX500 caliper is enough to stand it on its nose.

Of course a GT750 is slightly more portly, I mean substantial, but it might just work.
rngdng
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Post by rngdng »

I tried my bike with a single ex500 caliper, and it worked fine, but I had already gotten used to the feel of two ex500 calipers. It stops.



Lane
If you stroke it more than twice; you're playing with it.

Too many bikes, too much time, ENOUGH SPACE, FINALLY! Never enough money.........
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tz375
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Post by tz375 »

LAne,

How bad is stock disk brake material? I was under the impression that teh Coefficient of friction on old stainless was a lot less than modern disk material or is it not enough of a difference to worry about?

In fact I was figuring a friction coeficient between HH pads and modern rusty disk to be almost twice as high as old stainless.
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tz375
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Post by tz375 »

Lane, what sized master cylinder did you use with single or twin EX calipers?
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tz375
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Post by tz375 »

Well the welding looks fine, but now I have them mocked up more correctly, I think I'll have to move both calipers inwards slightly. maybe a washer between teh brackets and the fork sliders will be enough.
rngdng
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Post by rngdng »

tz375 wrote:LAne,

How bad is stock disk brake material? I was under the impression that teh Coefficient of friction on old stainless was a lot less than modern disk material or is it not enough of a difference to worry about?

In fact I was figuring a friction coeficient between HH pads and modern rusty disk to be almost twice as high as old stainless.

I don't have any idea. The stock disks worked fine, but I didn't use the HH pads. I don't remember what pads I bought; whatever the dealer had in stock. I have Katana disks on it now. They're slightly smaller in diameter so I had to move one mounting bolt on each caliper mount to swing them down enough.


Lane
If you stroke it more than twice; you're playing with it.

Too many bikes, too much time, ENOUGH SPACE, FINALLY! Never enough money.........
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tz375
Moto GP
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Joined: Mon Nov 03, 2008 10:47 am
Location: Illinois

Post by tz375 »

I'm going to start with one disk and see how that works out. As long as that experiment isn't a total disaster, I can always add the second disk later.

http://pinkpossum.com/GT750/phattrakka2/p5brakes.htm
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