Author Topic: Structural integrity of Stock forks w/ out fender?  (Read 46780 times)

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Offline Roach

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #250 on: February 24, 2011, 09:14:23 AM »
fast from the past doesnt sell anything for the 550 any year..

that being said i still dont know if the one for the 500 will fit?
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Offline MCRider

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #251 on: February 24, 2011, 09:34:26 AM »
fast from the past doesnt sell anything for the 550 any year..

that being said i still dont know if the one for the 500 will fit?
Man for the 400 and 500/550, I'd give that TKat guy a shout. (Prior posts) Custom made and reasonable.

You may have some side fender clearance issues. I'd remove the stock fender fork bracket and hang the fender from the fork brace. Cleaner.
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Offline somesuch

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #252 on: February 26, 2011, 12:11:22 AM »
Yea, I talke to Tkat today, and he said he would do it if he can get the 400 and 500 forks measured. Shoot him an email with dimensions.

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Offline socalenduro

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #253 on: March 02, 2011, 04:10:25 PM »
i just tested my 350f and wish i hadnt...
standing in front of the bike, holding the wheel straight between my knees i turned the handle bars.
the fork twists quite easily qith and without the fork brace (stock with fender drilled out/off) in place

even with a fork brace above the wheel it seems like it needs to be welded or bolted into place on each leg (not just clamped) to over come that kind of force. Wide bars give lots of leverage

Offline Retro Rocket

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #254 on: March 02, 2011, 04:21:26 PM »
Oh yes, there is heaps of inherent flex in these old front ends, i can't understand anyone arguing otherwise, bracing makes a difference, whether it be a small difference or not, and without it i would have to change the way i ride, for example, braking deep into a corner, thats where i notice it most. I ride fairly sedately now, but by the sounds of things some guys here would still think i ride hard, i will say i ride hard enough to notice the difference between a braced and unbraced front end....My K build has 43mm forks and i will still use a brace....

Mick
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Offline MCRider

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #255 on: March 02, 2011, 04:25:16 PM »
RR: Yup.
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Ron
1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
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Offline somesuch

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #256 on: March 02, 2011, 04:25:32 PM »
i just tested my 350f and wish i hadnt...
standing in front of the bike, holding the wheel straight between my knees i turned the handle bars.
the fork twists quite easily qith and without the fork brace (stock with fender drilled out/off) in place

even with a fork brace above the wheel it seems like it needs to be welded or bolted into place on each leg (not just clamped) to over come that kind of force. Wide bars give lots of leverage

the surface area of the clamp is very large for the force/direction of force, and there is no problem at all. It is kind of like the triple clamp is clamped on the forks, and not welded to them.  You will be very surprised to repeat the same test with the brace on, and you will be even more impressed by how the bike feels when riding aggressively. Once you bolt it on, you will see how strong the brace really is. It is much better than another brand (it was supposed to be model specific) I had that came with a shim (looked like a slice of beer can) to wrap around the fork leg. I can only assume that the generic brace with different size shims was used to fit many different models.

The Tkat brace is really over engineered, no worries :)

--Nick




Offline socalenduro

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #257 on: March 03, 2011, 06:31:36 AM »
Oh yes, there is heaps of inherent flex in these old front ends, i can't understand anyone arguing otherwise, bracing makes a difference, whether it be a small difference or not, and without it i would have to change the way i ride, for example, braking deep into a corner, thats where i notice it most. I ride fairly sedately now, but by the sounds of things some guys here would still think i ride hard, i will say i ride hard enough to notice the difference between a braced and unbraced front end....My K build has 43mm forks and i will still use a brace....

Mick
I ride like a little girl, but i still want a front end thats stiffer than a 1990s mountain bike
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Offline stueveone

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #258 on: March 05, 2011, 01:23:54 PM »
You don't think you need a fork brace until after you ride a bike where one is installed.

Night & Day.

ALso: RR you shouldn't be breaking at all in turns mate! 'Tis poor form!
« Last Edit: March 05, 2011, 01:27:00 PM by stueveone »

Offline fatmatt650

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #259 on: March 05, 2011, 03:55:27 PM »
This whole discussion is just silly. I simply used TWO zip ties per side to hold my Dunstall fiberglass fender on thereby DOUBLING both clamping force and area. I now have a front end that is TWICE as stiff laterally than the factory set  up and independent testing has confirmed that is now 378% more "CafeRacery"tm than before!
Unfortunately, standard zip ties are insufficient for this application. Luckily, I recently acquired a stockpile of these special "CafeRacery"tm zip ties from a Japanese estate sale and am making them available to you for the low, low price of only $17.95 ea. Four are required for installation. Instructions included w/ purchase. 
So much to do, so little time.

Offline MCRider

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #260 on: March 05, 2011, 04:57:07 PM »
"ALso: RR you shouldn't be breaking at all in turns mate! 'Tis poor form!"

I would hope he doesn't break in the turns also, nor on the straightaways.

Now braking is another issue...  ;D   ;) 

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Ron
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"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."

Offline stueveone

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #261 on: March 05, 2011, 05:18:05 PM »
"ALso: RR you shouldn't be breaking at all in turns mate! 'Tis poor form!"

I would hope he doesn't break in the turns also, nor on the straightaways.

Now braking is another issue...  ;D   ;) 



I blame whisky for that grammatical error! But yeah, breaking around a turn is even worse than braking!

Offline Retro Rocket

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #262 on: March 05, 2011, 09:51:01 PM »

ALso: RR you shouldn't be breaking at all in turns mate! 'Tis poor form!

I hope you are kidding mate, i always brake into the start of a corner, always have and always will. Some of you guys must have weird riding styles. Ever ridden on a race track.? if you aren't braking late and turning in whilst doing it you get left behind. Watch the Moto GP and you will see it in every corner... ;)
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Offline stueveone

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #263 on: March 06, 2011, 12:13:02 AM »
Notice he gets all of his braking and downshifting done before the corner?
There's also some people that will say easing off the brakes into the start of a corner is proper technique. Like "trail braking".
I haven't heard of anyone advocating hard braking while IN corners. Maybe I'm reading the wrong books?!!!


Offline Retro Rocket

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #264 on: March 06, 2011, 02:23:52 AM »
I'm talking about entering a corner as you brake and tip in whilst still brushing off speed. You are still leaning and braking as you enter the corner.I didn't say braking in the middle of the corner. I don't know if i am explaining it correctly but if you only rely on engine braking as you tip in you are wasting precious tenths. Watch Moto GP or World superbikes and you will see the back wheel in the air and going out sideways, thats because they are still braking heavily as they set up for the corner but they have already started entry whilst under brakes, then you need a smooth transition between that and a trailing throttle until you ease on the gas to exit the corner . Knowing where to get off the brake is the trick. You can also use the back brake to help stop the rear wheel spin when exiting the corner under power.
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Offline Steve_K

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #265 on: March 06, 2011, 05:43:53 AM »
Riding at WSB and Mtg levels is not possible on the the street, but being able to brake leaned over is important. 

I read that a Mtg rider will enter the corner hard on the front brakes, flick it to his knee, adjust throttle(for available traction), use the rear brake to controll wheel spin, weight the footpegs(Raine was said to wear out a pair boots in a race), push the bike up with your knee(Diahann said he did that 2 or 4 times a lap), ease off the brakes, use the front brake to give the front tire some traction, and then square off the turn.  The rider is also thinking on how to pass the rider ahead and deal with tires that are going off.  I don't wonder why they are paid big money. 

Sorry,I got off topic,  I do brake into the corner, and I try to most of the braking straight up, but that is not always possible.  When I ride the twisters, I tell my friends I do not use brakes, just engine braking.  For me its a fun way to judge corner speed.
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Offline seanbarney41

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #266 on: March 06, 2011, 09:54:25 AM »
What are wsb and mtg levels?...guessing its something to do with road racing?
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Offline Roach

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #267 on: March 06, 2011, 10:02:46 AM »
wsb= world superbike
mtgp= moto grand prix
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Offline Roach

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #268 on: March 06, 2011, 10:06:35 AM »
still havent seen the question i posted up answerd ....

is the 500 fork the same as the 550 fork are the legs the same distance apart if so would a 500 brace work on my 550?
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Offline seanbarney41

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #269 on: March 06, 2011, 10:14:24 AM »
wsb= world superbike
mtgp= moto grand prix
duh
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Offline Retro Rocket

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #270 on: March 06, 2011, 02:26:59 PM »
Riding at WSB and Mtg levels is not possible on the the street, but being able to brake leaned over is important. 

I read that a Mtg rider will enter the corner hard on the front brakes, flick it to his knee, adjust throttle(for available traction), use the rear brake to controll wheel spin, weight the footpegs(Raine was said to wear out a pair boots in a race), push the bike up with your knee(Diahann said he did that 2 or 4 times a lap), ease off the brakes, use the front brake to give the front tire some traction, and then square off the turn.  The rider is also thinking on how to pass the rider ahead and deal with tires that are going off.  I don't wonder why they are paid big money. 

Sorry,I got off topic,  I do brake into the corner, and I try to most of the braking straight up, but that is not always possible.  When I ride the twisters, I tell my friends I do not use brakes, just engine braking.  For me its a fun way to judge corner speed.
Steve

You correct with everything you have said there Steve, I only used Moyo GP as an example to see what i was referring too. Watched a cool TV show  last night that was all about Laguna Seca Race track in Cali, it featured Nicky Hayden , Troy Bayliss, Rossi and others, the braking technique i am referring too was clearly visible with the front fairing mounted camera on Haydens Bike, actually you would be surprised to see how far into the corner they brake..... ;)

Mick
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Offline stueveone

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #271 on: March 06, 2011, 11:57:21 PM »
Gotcha RR. Did a little more reading and sounds like you're advocating the trail braking technique. I read braking "in" a turn as you waiting to grab a handful of lever at the apex. Either way, from the sound of it you know what the you're doing!

But I totally agree that the fork brace is very apparent while braking into the start of a turn. I'm really starting to think the fork brace is the single most drastically noticeable suspension upgrade that I've done. Though I'm still waiting on my new Ikon rear shocks to come in the mail. . .

Offline Retro Rocket

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Re: Structural integrity of Stock forks w/ out fender?
« Reply #272 on: March 07, 2011, 12:10:34 AM »
Gotcha RR. Did a little more reading and sounds like you're advocating the trail braking technique. I read braking "in" a turn as you waiting to grab a handful of lever at the apex. Either way, from the sound of it you know what the you're doing!

But I totally agree that the fork brace is very apparent while braking into the start of a turn. I'm really starting to think the fork brace is the single most drastically noticeable suspension upgrade that I've done. Though I'm still waiting on my new Ikon rear shocks to come in the mail. . .

Its good to hear from someone that rides hard enough to feel and understand the difference made by having a tighter front end. Sometimes its easy to take for granted that everyone knows what i am talking about, i find typing a poor way to communicate, rather have a chat over a couple of nice cold beers after a spirited ride.... ;D ;)

Mick
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If You can't fix it with a hammer, You've got an electrical problem.