SuzukiSavage.com - Print Page

SuzukiSavage.com
/cgi-bin/YaBB.pl
General Category >> Rubber Side Down! >> Fork Brace Physics
/cgi-bin/YaBB.pl?num=1155317695

Message started by Tkat on 08/11/06 at 10:34:55

Title: Fork Brace Physics
Post by Tkat on 08/11/06 at 10:34:55

Well, @ long last I’ve figured how to post to this list --Ta-Da!

I’ve been asked by several people exactly what a fork brace is, how does it work, and why do they need one.

I read the blurb about the SuperBrace & it seemed, perhaps, a bit technical for some. Follow’n this msg is s’thing I wrote up for the XS1100 list years ago that is a dirt simple explanation.

Do you need one? I dunno. Some front ends are rock solid as is. Others are limp willows. You decide. Here’s a way to check.

Stand in front of the bike and clamp the front wheel between your knees. Grab the handle bars on the grips and try to twist the bars. Can you? How much? My XJ900 is rock solid. The XS1100s are wet noodles --- that’s what started the project 1500+ units & almost a decade ago.

Tip: Some late model Savages have plastic stone shields on the top of the sliders. They snap into grooves in the slider. The easy way to get ‘em off is to take a hard piece of wood or soft metal and use it as a punch. Place it against the under side of the protector. Whack the end of the punch w/ a hammer. The plastic will [should] pop up out of the groove. You can then cut ‘em off.

====================================

Fork Brace Physics

That wheel spinning down there is a Hell of a gyro. Twist the bars or lean the bike and s'thing moves --- typically the bars or the bike. BUT NOT THE WHEEL!! The gyro action is just too strong. And what's planted on the road and controls the direction of travel? That's right, Homer, the wheel!

The result is "lazy steering". The weaker the connection between the input and the wheel, the sloppier the directional response. Long, skinny forks = weak link.

A F/B ties the legs together in the middle so the unsupported columns now act as a beam, hence increasing the stiffness of the now single member. Increased stiffness = more positive output/input ratio and the bike tends to go where it's pointed much more quickly.

Conversely, if the wheel is "kicked" by a rut, etc. the H/B doesn't see the directional change as quickly as a stiffer column will.

And, OK, so you say you're not a boy-racer and don't power the machine thru turns --- just a cruiser on Sundays. Fair enuf. But what about that LOL in her USS Caddy land yacht that target fixates on a yard sale sign that requires an immediate left turn? 'Nuff said.

And here endth the Begining Physics 101 Lecture for the day.

:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

Title: Re: Fork Brace Physics
Post by Starlifter on 08/11/06 at 18:15:22

Thanks TKAT, that is very useful information.

Title: Re: Fork Brace Physics
Post by lancer on 08/11/06 at 21:07:30

Good info, short and to the point.

Thank you for your efforts.

Title: Re: Fork Brace Physics
Post by Max_Morley on 08/12/06 at 09:08:27

And his $90.00 fork brace works and fits my 96 and even clears the higher crown full fender I have. Max

Title: Re: Fork Brace Physics
Post by bikingb on 08/12/06 at 09:21:12

I just ordered mine last week. Can hardly wait to get it and install it!!

Title: Re: Fork Brace Physics
Post by babbalou on 08/12/06 at 09:33:33

I've got Tkat's fork brace too & I really needed it. Before I got the brace I was considering dropping down to 10 weight fork oil to smooth out the ride. With the brace I went up to 20 weight. It's that much smoother now. I could have stayed with 15 weight but I often ride hard & I'm over 200 pounds (OK, way over :P) so the increased damping of the 20W adds control & reduced fork dive when braking. Anyway, when I'm leaned over in a fast, bumpy corner now, it feels like my front tire is spending a lot less time in the air than it did before the brace. Best $90 I've spent in a long time.

Title: Re: Fork Brace Physics
Post by smokey02 on 08/12/06 at 13:32:51

Hi Tkat
I got your email, wish I lived closer for that install, but I'm 400 miles south of you. I'm putting the check in the mail today. Thanks so much.

Title: Re: Fork Brace Physics
Post by WKD on 08/12/06 at 17:12:12

Hey Tkat, that is a great explanation. I read the Superbrace and it made sense to me but your description gives it that real world touch.

BTW, I hope you got my cheque I sent it the middle of last week.

Title: Re: Fork Brace Physics
Post by DianeS. on 08/14/06 at 13:45:52

Thanks tkat!

I just received my brace today in the mail! Will put it on soon and see how it feels. ;D

Judging by your pics in the Marketplace, it goes on the forks just below the black fork seals or covers - whatever they are called???? My bike is a 2000, so it doesn't have the newer stone shields.

DianeS

Title: Re: Fork Brace Physics
Post by WKD on 08/14/06 at 19:04:01

Hey wow, I received mine tonight too. I couldn't wait so I put it on and WOW night meet day... I wish somebody would have kicked my butt and I picked one up sooner. I just went on a short 30 min ride but the handling is so much better, smoother (I didn't really expect that) and it may have been just me but I think it even cut down on the vibration too.

I was expecting good things but not alot because I am not an agressive rider, I wanted a cruiser because I wanted to cruise but this thing out did all expectations..

Great job Tkat, very quality product and great service.

Title: Re: Fork Brace Physics
Post by klx650sm2002 on 08/15/06 at 03:33:20

I'm gettin' jealous coz I can't fit a fork brace on KLX (USD forks), I'll just have to make do with a 20mm front wheel spindle.

Clive W :D

Title: Re: Fork Brace Physics
Post by bikingb on 08/15/06 at 18:06:14

Get a savage man.

Totally love love love my fork brace. Put it on today. The bike feels better, period.

Now for those metzlers.

Title: Re: Fork Brace Physics
Post by Reelthing on 08/15/06 at 21:14:10

ME880's right?

Title: Re: Fork Brace Physics
Post by smokey02 on 08/27/06 at 11:28:06

Hi Tkat,
Wanted to thank you for the fork brace. I got it installed last week, but had to wait for my new battery to arrive. (BigCrank agm) Took my bike for a ride yesterday on some of the streets that have long cracks filled with tar. I used to avoid those because they would grab at my front wheel and make the bike wobble. Now I can still feel the up and down bumps, but no sideways wobble anymore. Went on the 210 freeway too, feels much better, stays in a straight line.