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Discussion Starter #1
so it kinda bothers me that roskos bike weighs less than mine does, even though i have a 10 pound heavier brake. has anyone lightened a gt750 brake, only cutting aluminum? how much weight did you save. im just wondering if i should be looking other places to hack out weight. although at this point i have no idea where i could do that. and rosko put this idea up there, what are all yer thoughts on backing up to a cb450 brake. that really isnt a thought in my mind at this point, but was wondering what people thought of having that brake with the right compound with the lighter bike versus a bigger heavier brake on the same lite bike. im not asking what i should do, im just asking for opinions. im also going to have the rear lightened up too.

so any thoughts or ideas, id love to know what people think about this.

jc
 

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At our level of riding, I'd sacrifice weight gain for a bomber brake. Seems alot of passing is done in the brake zones so I'd want to brake as late as possibly. I'd love to have a 4LS on the Honda
Then again, with about 30 hp on tap, maybe shaving weight is a better thing to pursue.

What does Roskos bike weight anyways? Under 300lbs?

Jeff
 

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clancy-

i have the 450 brake and ran vesrah non-race linings the last two years, my bike is tons heavier than yours despite the lighter brake and i was still in front of you. but then again, and i don't know much, but it seems like the biggest benefit of a lighter FCB bike is so you can slow it down faster (launch isn't a big deal and exit speed has more to do with the rider), so if the biggest benefit to lightening is in the braking zone and you give up the 4LS H20 buffalo for the lighter CB brake, it may be a wash?

go for the lightest 350...a race you could actually win.

-tt
 

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I saw this GT750 brake on a recent E-bay listed Triton. While I'm sure it saved some weight, to me the drilling looks almost a little too aggressive for racing use. I'd be checking the hub for cracks between the spoke holes every time I came off the track. It sure looks good though.

Cheers, Bret @ Glass from the Past



Edited by - bret on Dec 26 2007 12:22:26 PM

Edited by - bret on Dec 26 2007 12:23:53 PM
 

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Joe,
You already won that battle!
Your bike is lighter even WITH that 35 lb. brake.

My humble and green opinion on the brake is that while a brake like the cl450 drum is fine for the 350's, a brake with major stopping power like the water buffalo is going to be an advantage (at any weight) especially on tech tracks like loudon and summit.




BORN TO LURK, FORCED TO WORK.
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quote:
and the brake is unsprung weight.....?
So is my fat ass and stomach (I know it ain't unsprung weight, but hell it is a comical response). All this race reduction doesn't mean squat if you dove into the Christmas cookies one too many times and have a gut like me!

Yeller'
---
"People are more violently opposed to fur than leather because it's safer to harass rich women than motorcycle gangs”
 

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Discussion Starter #11
my brakes really not going anywhere. rosko, your bike was about 5lbs lighter than mine if i remember. or maybe mine was lighter than yours by that much. i do have the big brake, but youre running the battery. well, you were. you get rid of that battery and id bet your bike if it wasnt before will be lighter than mine. how i dont know. you got steel rims still?? and i think you probably have one of the more minimal bikes out there. id even bet the metal original tanks are lighter than the setup i have.

guess im wondering 2 things. does saving 10lbs on an already lite bike mean a hell of alot if it means being equal to the other bikes on the grid? with the other bikes on the grid being about the same weight or heavier, and if you had the chance to shave 10lbs, off of an already lite bike, would getting rid of the brake and going with the 450 be the way to go. possibly, and im only saying possibly here, losing some brake. the pic of that brake bret posted has some pretty huge holes in it. chris' brake is done that way but the holes are not as big. and i cant see that it saved that much weight. chris also has extra holes drilled in the webbing inside. thats not alot of alum. so would it be worth milling the brake a little to save that amount of weight? i would think if you were going to put it under the knife, youd have to go pretty extreme to make it worth while just doing alum. does that make sense? i guess i dont think the bike is to the point where removing ounces is going to really make any difference. i dont think it ever will. so. anyone have one, shave it, then weigh it?? wondering what i can expect from puttin one on a diet. is it really worth that much of i can get the weight off someplace else maybe.

jc
 

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Discussion Starter #12
jeff, both of our bikes weighed around 270 lbs i think. maybe just under. i think i remember craig saying his weighed 266 (?), and ours werent that much heavier. but he has a kick ass weight distribution and waay better geometry.

jc
 

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It certainly would be a tough question for me...I love light, I also love lots of brake.

Might be able to take about a pound off by drilling, the drilling in that photo looks a tad radical, I would have gone one size smaller and kept the hole from infringing on the drum section. You can also center bore all the pivots and cams (which are steel) as seen here: http://www.jrbranson.com/showandtell.htm . The brake arms could be safely drilled a bit. BUT, the absolute biggest weight savings you can get is to have the liner turned down as far as practical, It's all steel and probably represents half the weight of the brake. You could probably remove a couple of pounds of steel liner. Problem is that will change the arc a bit and require new shoes with thicker compound. Another upside is it slightly increases the ID of the drum making it an even stronger brake.

If I was building an FCB from scratch I'd lean towards the best built 450 brake I could do. If the FCB already had a GT brake I'd probably go with that.

Bear in mind removing ten pounds from the front wheel would have numerous effects on the bike. From the expected advantages of a less dead weight, less unsprung weight, less rotational mass. Which means a tad better accleration, tad less weight to decelerate, quicker turn in, better front suspension behavior etc.

You'd have to be a fairly fast rider to enjoy the "racing" benefits of a GT brake....I mean if you out brake someone you need to be able to stay in front of them when you do. But even if you are not the fastest guy out there a GT brake gives you a margin of error compared to less powerful brakes.

One thing to consider is what the front running FCB riders are using. Take a look at LoneWolf, using a 305/450 brake I think. His bike/rider weight has got to be 40-50 pounds more than Joe for instance.

But yeah, tough call. You could probably sell that brake for enough to build a new front wheel.
JohnnyB

PS. When my shipment of race compound shoes come in I'm going to experiment with building the lightest 305/450 brake I can build. Do all the usual tricks and turn down the liner right to the OEM spec limit, then arc a set of shoes to match. I'll report on just how much weight can be taken off. Target would be 8 lbs, the same as a T500 brake..I think stock weight of a 305/450 is around 11 lbs.



Edited by - jbranson on Dec 26 2007 2:07:28 PM
 

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Discussion Starter #15
lonewolf is going to have a 750 brake next season. ive been kicking around turning the liner down. but that creates so much more work. ive been afraid to call and talk to mike morse about it sinc ei know itll be a 40 min long conversation. not that i dont like the guy, i do, and hes got a freakin brain, but i havent wanted to sit on the phone that long.

jc
 

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Pretty sure his FCB is a 305/450...could be wrong. He replaced his Suzuki T500 he bent a year or so ago in the crash where TT got ran over.
At least I'm pretty sure he won the FCB championship this year with a 305/450 brake.

Tex....check out the feedback I left you :)

JohnnyB

PS. In that photo of the GT brake...that stay is WAY stupid big. People tend to way overdo the stays...they are in tensile load, you could use a little piece of 1/8" thick aluminum and get away with it. I prefer using a piece of 1/8" x 1" Stainless or Ti.



Edited by - jbranson on Dec 26 2007 2:18:03 PM
 

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quote:
lonewolf is going to have a 750 brake next season. ive been kicking around turning the liner down. but that creates so much more work.
Yup, that's what you do if you want to take weight off of a GT750 brake.
The drum liner is very thick, and can almost be cut down to half it's width. But then your shoes won't match the drum anymore.

But you know that.

Or you could just quit your crying and ride the bike. Or buy my RD350. You'll win Middleweight that way.
 

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Discussion Starter #18
i havent even finished this bike and now someone wants to sell me another!? i sent lonewolf a rim and spokes for a gt750 brake. im only guessing its going on the racer. i wasnt going to mention that brake stay in the pic. but its rediculous. way over kill. i like steve d's. wiht the "ducati" drilled into it. yeah, i know the liner should be turned. but thats so much work. then haveing the shoes re lined, or arced. although, i have brand new shoes with very few races on them. maybe 4 weekends. so they could probably still be used. hmmm....

jc
 

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While it is true that it REALLY all comes down to the rider we are tinkers and building and re-building the machine is a big part of the fun... for us. Some folks don't feel the same way. I'm as green as they come and my riding has miles to go in the way of experience, doesn't mean I won't be reconstructing the ride at every opportunty!

Joe, you have 6 lbs. on me as per the NHIS scale. you have a 35lb. brake, I have a stock tank, cb450 rear brake, a total loss ignition and 530 chain... just to make it fun the heavier FCB at NHIS next time buys breakfast.

anyway, It's not like joe is going to work on his bike! He'll make a 'to-do' list and frantically bang it out a week before summit like the rest of us!



BORN TO LURK, FORCED TO WORK.
www.NYCvinMoto.com
www.VinMoto.org
 
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