Page 1 of 3

fork brace what do ya think?

Posted: Sat Dec 05, 2009 10:18 pm
by 91fzr600r
i am making a fork brace from 1/2 inch 6061 billet aluminum to replace the stock 1/8 inch one. :banana: what do ya think about that idea?? :deal:

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 12:16 am
by kilika2
I think this just about sums it up... :worthlesswithoutpics:

:headbang:

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 2:06 am
by sweekster
Do a search it's been discussed before

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 3:34 am
by 91fzr600r
dam! kinda harsh? LOL2 i just picked up the material at 7:00 PM IDK ill post pic when i get started.....
sweekster wrote:Do a search it's been discussed before
i just did a search and people say it don't work. and that its pointless because it bolts into a plastic finder.... well my finder no longer bolts there, so the tabs on the fork tubes only purpose now is fork brace.....and my front tire tread is cupping. i did some research on the subject and came up with "its the fork tubes trying 2 move independently in hard corners. so by installing a R1 finder (bolts on the side not on top) it frees up the mounting bracket for a way thicker than stock fork brace"..so my thought was i would see if people are haveing the same issue? and if any one tryed a thicker fork brace. thats all. canofworms will post pics later 2marrow...peace bandana

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 6:09 am
by yamaha_george
91fzr600r wrote:dam! kinda harsh? LOL2 i just picked up the material at 7:00 PM IDK ill post pic when i get started.....
sweekster wrote:Do a search it's been discussed before
i just did a search and people say it don't work. and that its pointless because it bolts into a plastic finder.... well my finder no longer bolts there, so the tabs on the fork tubes only purpose now is fork brace.....and my front tire tread is cupping. i did some research on the subject and came up with "its the fork tubes trying 2 move independently in hard corners. so by installing a R1 finder (bolts on the side not on top) it frees up the mounting bracket for a way thicker than stock fork brace"..so my thought was i would see if people are haveing the same issue? and if any one tryed a thicker fork brace. thats all. canofworms will post pics later 2marrow...peace bandana
91,
since the fork leg mounting holes are feed up might as well put them to use by all means, however that will not cure the problem of your tyre cupping (tyre cupping has been discussed and I seem to remember diagnosis as to why is in the WIKI)

Since you have access to a machine shop your time could be more productive by fixing the problem entirely.

The solution is a bigger diameter front axle. (this is discussed on the forum & parts (bearings) are listed in the WIKI ).


How do I know this works ? Eric Buell (Ex. Buel Motors) & I back In the early '80's were discusing bits & bobs to do with stability and ridabilty of one of my race bikes. His solution to my high speed weave problem was to reduce front shock flex.

With a wimpy size axle (back in the day it was 15mm) allowed the two front shocks to work independantly of each other as the axle flexed under load we are talking 90mph with knee down & a very nerve wracking back end wiggle.

I just know some smarty is gonna say should have used a steering damper :-}

What I did was replace the 15mm with 25mm ( I was lucky the bearings were the same O/D ) the corners I used to testing went from 90 with buttocks clenched to 125 & 130mph and the bike tracked as though on rails

. I was gone so long testing grinning like a jackal that my mechanic had closed the shop early to come and find out if I was ok. I let him have the bike and he was out for an hour and had trouble taking his helmet off past the grin. Needless to say he wanted a new set up to.

If you look at fast state of the art bikes (Ducati's ) they have massive front axle tubes (part of the size is required because it is a tube)

Please take a look at the idea as no one so far has had the facility to do it on an FZR (myself included as my friendly neighbourhood machine shop boss retired earlier this year.)

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 9:27 am
by kilika2
Yeah I didnt know if you ment what I said was harsh or sweek but if me I was just joking around, I ment that I wanted to see the awesomeness when you were done, but I would go with the 130 mph grinfest that YG described.

Chris

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 12:20 pm
by 91fzr600r
joking about harsh LOL... :rofl:
yamaha_george makes a vary good point about the axle . i will be doing this mod as well as the fork brace. he said the axle flexed under load, we are talking 90mph with knee down & a very nerve wracking back end wiggle..... mine was doing the exact same thing so i also installed a GPR stabilizer designed for a 06 zx6r.... it helped with the wobble... i will do the axle mod in a few weeks when i tare down my front end to inspect & replace headset bearings, fork seals & do a general tune up..... thanx guyz :cheers:

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 1:00 pm
by yamaha_george
91fzr600r wrote:joking about harsh LOL... :rofl:
yamaha_george makes a vary good point about the axle . i will be doing this mod as well as the fork brace. he said the axle flexed under load, we are talking 90mph with knee down & a very nerve wracking back end wiggle..... mine was doing the exact same thing so i also installed a GPR stabilizer designed for a 06 zx6r.... it helped with the wobble... i will do the axle mod in a few weeks when i tare down my front end to inspect & replace headset bearings, fork seals & do a general tune up..... thanx guyz :cheers:
91,
As I stated the NEW bearing sizes for the bigger front axle are in the WIKI.

HOWEVER I have not checked how much "meat" there is in the bottom of the fork where the damper rod Allen head bolt goes. You will need to bore out or remake the wheels internal spacer and the two wheel side spacers.

Please be aware that the wheel internal spacer is a high accuracy piece as far as length is concerned.



As a personal request as Site Director & one of the WIKI keepers PLEASE document with dimensions & part numbers plus the usual request for lots of pictures.

There is no need to write this stuff up your self in the WIKI if you send plain text & pictures to me I will WIKI ize the deal for you.

email me at george AT saltmine DOT org DOT uk if you need any help or advice and be aware that I did publish a how to with making tools for the seal change.
in the WIKI.

Thanks on behalf of the "gang"
Y-Geo.

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 1:19 pm
by 91fzr600r
will do. thanx george :cheers:

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 2:41 pm
by ragedigital
It might be better just to go the route of installing some YZF600 forks. I do believe the axle is heavier, the forks are certainly larger and more adjustable. Plus, they should bolt right on.

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 2:45 pm
by 91fzr600r
is there a write up on YZF600 forks install ? anyone have links?

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 2:53 pm
by ragedigital
I might be wrong, but I believe it goes something like this:

1. Buy YZF600 fork set-up
2. Remove FZR600 fork set-up
3. Install YZF600 forks
4. Sell FZR600 forks
5. Enjoy the ride

All kidding aside, I do believe they bolt right up. You'll just have to buy all the bits to go with the new forks: triples, rim, calipers, clip-ons, etc...

Image

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 3:15 pm
by yamaha_george
ragedigital wrote:It might be better just to go the route of installing some YZF600 forks. I do believe the axle is heavier, the forks are certainly larger and more adjustable. Plus, they should bolt right on.
Darrin,
you mean R6 version YZF or the early model yzf if so what year?
Thnx
Y-G

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 3:43 pm
by ragedigital
I used YZF600 forks, 96+, if memory serves me correctly. I do believe that either in 96 or 97 is when the YZF forks started coming with pre-load, compression and rebound adjustments.

Re: fork brace what do ya think?

Posted: Sun Dec 06, 2009 4:50 pm
by yamaha_george
ragedigital wrote:I used YZF600 forks, 96+, if memory serves me correctly. I do believe that either in 96 or 97 is when the YZF forks started coming with pre-load, compression and rebound adjustments.
THNX Boss