Author Topic: fork braces: do they help front end wobble at speed?  (Read 11625 times)

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Offline FastRocket

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Re: fork braces: do they help front end wobble at speed?
« Reply #25 on: July 12, 2014, 10:27:59 pm »
Just realized reading through this that I have not done the fork spring mod . Will look into that this winter .

Thanks kids

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Offline Daytona_Mike

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Re: fork braces: do they help front end wobble at speed?
« Reply #26 on: July 13, 2014, 02:31:06 pm »
:)) ;) To sport rider.  When I said that I went to a larger tire I meant that I went from a 120/70 vr18 to a 120/90 vr18.  My shakes and wobble problem was cured when I replaced the tire to its proper size, replaced the front fender, and removed the fork brace!
The (more) proper size is 110/80/18 for the newer model C10's. Try that size the next time you change the front tire.
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Offline Daytona_Mike

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Re: fork braces: do they help front end wobble at speed?
« Reply #27 on: July 13, 2014, 02:55:53 pm »
New fork oil . Springs tightened down . Steering head bearings replaced . Adjusted rear dampening to full for a stiffer more sport ride . Adjusted Air Shock pressure . Installed murph fork braces prior to my 5 + hr ride  and still had horrid handling .

Poor bike.
Springs tightened down. What do you mean? You screwed all the way in your Pre-Load Adjusters? That raises the front of the bike higher.
Steering head bearings replaced  Those bearings will settle which means after some riding they  will have to be readjusted (tightened again) and maybe one more time after that before they are fully settled.
Adjusted rear dampening to full for a stiffer more sport ride . I dont know about having to be  at 'Full'. 3 to 4 should be more than enough. All the way would be too stiff unless the bike is carrying a lot of weight (you and a passenger and luggage).
Adjusted Air Shock pressure. What pressure are you at now?
Installed murph fork braces Did you 'shim' them as you installed them?If not most likely you bound up the forks. Fork Braces need to be shimmed.
Do you know how to check for 'stiction' or 'fork  binding'?
Put 40 psi in the front and 42 in the back.
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Offline FastRocket

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Re: fork braces: do they help front end wobble at speed?
« Reply #28 on: July 15, 2014, 08:22:53 pm »
New fork oil . Springs tightened down . Steering head bearings replaced . Adjusted rear dampening to full for a stiffer more sport ride . Adjusted Air Shock pressure . Installed murph fork braces prior to my 5 + hr ride  and still had horrid handling .


Poor bike.
Quote
Springs tightened down. What do you mean? You screwed all the way in your Pre-Load Adjusters? That raises the front of the bike higher.


Had a bike mechanic screw them fully down to what I thought would reduced the break dive and I would like the front  higher but I did not realize it would raise the bike height .

Quote
Steering head bearings replaced  Those bearings will settle which means after some riding they  will have to be readjusted (tightened again) and maybe one more time after that before they are fully settled.

I only put a hundred miles or so on the bike after bearing replacements and only recently did I do the ride to Quebec and back . 600 or 700 miles total . So 800 miles on new steering head bearings .

Quote
Adjusted rear dampening to full for a stiffer more sport ride . I dont know about having to be  at 'Full'. 3 to 4 should be more than enough. All the way would be too stiff unless the bike is carrying a lot of weight (you and a passenger and luggage).

I have a passenger whom is a bit heavier than me . I am 190 lbs and 5' 10" . Yes 5 may be too much . I will try 3 or 4 next time out .

Correction . It was on #3 .


Quote
         
 Adjusted Air Shock pressure. What pressure are you at now?





Quote
Installed murph fork braces Did you 'shim' them as you installed them?If not most likely you bound up the forks. Fork Braces need to be shimmed.

 The Murph fork brace just slipped right into place . Not sure how to shim it to be honest . From a visual it all lines up .

Quote
Do you know how to check for 'stiction' or 'fork  binding'?

 Are you saying if I feel any wierd sensation though the forks when they are in travel mode ? Then I would say no . there is only smooth travel but it seems soft to me or maybe plush is a better word .

Quote
Put 40 psi in the front and 42 in the back.

 Ok . This I understand lol . I just checked the front . It was at 36 and the back was 38 . I will adjust them both as you say . The higher tire pressure should make this thing a lot easier at slow speeds . I was finding it tough on uneven surfaces .


Thanks for these updates D Mike ...
 
Awaiting more instructions  :beerchug:
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Offline GF-in-CA

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Re: fork braces: do they help front end wobble at speed?
« Reply #29 on: July 16, 2014, 02:38:09 am »
FastRocket,

As Mike stated, the preload adjusters effectively just raises and lowers the front of the bike.  They are used to set the static sag in the forks to optimize the suspension travel and to bring the front chassis geometry as close as possible to what the factory engineers had in mind.  With your weight, you will most likely not be able to bring the static sag to an acceptable level assuming you have the OEM springs.  The OEM springs are very soft, which also contributes to the brake dive you experience.  This is a very common issue with the C10, and the only real way of making it better is to install stiffer fork springs, either by buying new springs or cutting the OEM springs down and installing spacers above the springs.  You can read about cutting the springs down here:

http://forum.cog-online.org/index.php/topic,47329.0.html

As for stiction, the best way to test for it is to hold the front brake and bounce the front a few times, ending with a down stroke and letting the front end settle.  Mark or measure the location of the top of the lower fork tube.  Then pull up on the bars, release and determine the location of the top of the fork.  Determine the difference between the two numbers.  Somewhere around half an inch (13 mm) is a good number, if it is much more than that you should investigate the cause.

On the steering bearing, I've found that it doesn't take long for the bearing to get loose after installation, so given the mileage you state it is a good idea to check the adjustment again.

All your other settings seem reasonable.

Hope this helps,
Gary F.

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Offline FastRocket

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Re: fork braces: do they help front end wobble at speed?
« Reply #30 on: July 16, 2014, 10:55:36 am »
FastRocket,

As Mike stated, the preload adjusters effectively just raises and lowers the front of the bike.  They are used to set the static sag in the forks to optimize the suspension travel and to bring the front chassis geometry as close as possible to what the factory engineers had in mind.  With your weight, you will most likely not be able to bring the static sag to an acceptable level assuming you have the OEM springs.  The OEM springs are very soft, which also contributes to the brake dive you experience.  This is a very common issue with the C10, and the only real way of making it better is to install stiffer fork springs, either by buying new springs or cutting the OEM springs down and installing spacers above the springs.  You can read about cutting the springs down here:

http://forum.cog-online.org/index.php/topic,47329.0.html

As for stiction, the best way to test for it is to hold the front brake and bounce the front a few times, ending with a down stroke and letting the front end settle.  Mark or measure the location of the top of the lower fork tube.  Then pull up on the bars, release and determine the location of the top of the fork.  Determine the difference between the two numbers.  Somewhere around half an inch (13 mm) is a good number, if it is much more than that you should investigate the cause.

On the steering bearing, I've found that it doesn't take long for the bearing to get loose after installation, so given the mileage you state it is a good idea to check the adjustment again.

All your other settings seem reasonable.

Hope this helps,


Excellent information Gary . Thankyou . :beerchug:
Will test the stiction today .
I'll be doing the fork mod this winter or get stiffer springs as you suggest .
I'll check the steering bearing also .

Mike
2003 Concours
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1986 GPZ 550/1978 KE 175
 1975 H1-F 500
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Offline Roger M.

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Re: fork braces: do they help front end wobble at speed?
« Reply #31 on: July 18, 2014, 12:35:13 pm »



Someone lied to you.   :(

If you want a couch, get a Goldwing...just hop on one and you'll feel the difference immediately. I luvs ma Connie, but the more riding me n the missus does, the more I'm considering the Wing or something similar (Kawasaki Vaquero). Just wish they were lighter...(Connie too!). We're good for about an hour before she needs to stretch her legs.

That said, a front shake means something is wrong - bad tire, axle, fork oil low on one side, bad spring, wrong preload, etc.

Mine would get a slight hi-speed wobble behind/passing tractor trailers, until I did the fork spring mod, changed the fork oil, added a fork brace and got the preload right. Now she's solid behind almost anything, with FAR less brake dive.
[/quote]

I took the Vaquero for a test ride, my wife hated the ride as a passenger. I liked the ride, nice and plush. When we got back from the test ride, the bike was spewing oil from the bottom of the jug just above the lower end. When I looked at the other vaquero they had there, it was already seeping oil from the same location. I do a thorough web/forum search before any large purchases just to try and avoid any "buyer remorse"!!!


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Offline JimBob

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Re: fork braces: do they help front end wobble at speed?
« Reply #32 on: September 05, 2014, 06:13:29 pm »


Quote
Someone lied to you.   :(

If you want a couch, get a Goldwing...just hop on one and you'll feel the difference immediately. I luvs ma Connie, but the more riding me n the missus does, the more I'm considering the Wing or something similar (Kawasaki Vaquero). Just wish they were lighter...(Connie too!). We're good for about an hour before she needs to stretch her legs.

That said, a front shake means something is wrong - bad tire, axle, fork oil low on one side, bad spring, wrong preload, etc.

Mine would get a slight hi-speed wobble behind/passing tractor trailers, until I did the fork spring mod, changed the fork oil, added a fork brace and got the preload right. Now she's solid behind almost anything, with FAR less brake dive.

I took the Vaquero for a test ride, my wife hated the ride as a passenger. I liked the ride, nice and plush. When we got back from the test ride, the bike was spewing oil from the bottom of the jug just above the lower end. When I looked at the other vaquero they had there, it was already seeping oil from the same location. I do a thorough web/forum search before any large purchases just to try and avoid any "buyer remorse"!!!

Well dang - that's no bueno!

Any thoughts on what she didn't like about it? (Something fixable/adjustable perhaps, like a better saddle or a trunk/backrest)?

Offline gottaride

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Re: fork braces: do they help front end wobble at speed?
« Reply #33 on: September 07, 2014, 06:19:36 pm »
In stock configuration the first few years I had a few 85+ mph wobbles. Last spring I installed Sonic 1.1 springs and emulators. Much improvement in ride comfort and control but the wobble was still there. KB fork brace installed exactly according to the accompanying instruction solved the wobble and made a very noticeable improvement in low and high speed stability. Now it's time for a new rear shock.

Offline Colt45

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Re: fork braces: do they help front end wobble at speed?
« Reply #34 on: September 12, 2014, 03:48:17 pm »
I took off my front fender and now I have a wobble and shake was wondering if anyone has success with stabilizing front end with a fork brace?

I put on a brace I got from Murph and could never tell any difference.  The front fender acts like a small brace, apparently that's enough. 
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Offline gottaride

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Re: fork braces: do they help front end wobble at speed?
« Reply #35 on: September 28, 2014, 02:10:17 am »
Previously I stated that the brace solved my 85mph + wobble in the curves. Well it's reduced but not gone. I`m thinking the rear shock will need to be replaced to banish the wobble. The U-turn speed wobble is definately reduced.

Offline Mcfly

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Re: fork braces: do they help front end wobble at speed?
« Reply #36 on: September 29, 2014, 01:10:20 am »
Previously I stated that the brace solved my 85mph + wobble in the curves. Well it's reduced but not gone. I`m thinking the rear shock will need to be replaced to banish the wobble. The U-turn speed wobble is definately reduced.

"In the curves" is fairly important.  The fork brace is designed for this.  If your
wobble occurs when going straight, then there's an issue that needs to be resolved. 
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Offline gottaride

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Re: fork braces: do they help front end wobble at speed?
« Reply #37 on: September 29, 2014, 04:13:21 am »
Not wanting to hijack this thread so I briefly say the bike is rock steady up to 120 on the straights. Carving is steady up to about 90 but what brings on a brief wobble is either sudden roads changes like bumps and wheel ruts etc. Happens rarely but I agree it's a priority.

Offline FastRocket

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Re: fork braces: do they help front end wobble at speed?
« Reply #38 on: September 05, 2015, 07:16:06 am »
Well with a few adjustments and new Tires the bike has improved greatly . Seems the tires I bought the bike with may have been causing my grief tho they had lots of thread on them . Rides quite nicely now and super easy to move around at slow speeds or just shifting it around in the driveway . Surprisingly the bike now feels much lighter tho I know it is not . Front ture pressure is 40 and rear is 41 . I put rear dampaner to #2 instead of 3 and turned out the front fork adjusts 4 times .
 Initionally the bike was a handfull until I played with the tire air pressures and did the adjustments . Still have to replace fork springs this winter . I can now say that I finally enjoy riding my con ...
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Offline Rev Ryder

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Re: fork braces: do they help front end wobble at speed?
« Reply #39 on: September 05, 2015, 06:58:25 pm »
Not wanting to hijack this thread so I briefly say the bike is rock steady up to 120 on the straights. Carving is steady up to about 90 but what brings on a brief wobble is either sudden roads changes like bumps and wheel ruts etc. Happens rarely but I agree it's a priority.
When I used to hop off my Connie with 43mm forks and onto the stocker with fork brace, the difference was night and day when you talk high speed cornering with some bumpiness.  Even just pulling in the driveway at 5mph the difference is telling.  The brace does a fair bit, but cannot compensate for the rubbery fork stiffness of a stock Connie.  She'll ride well stock, better with a brace, totally transformed with a USD fork swap.  Just my .02


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Offline Mcfly

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Re: fork braces: do they help front end wobble at speed?
« Reply #40 on: September 05, 2015, 09:14:01 pm »
Not wanting to hijack this thread so I briefly say the bike is rock steady up to 120 on the straights. Carving is steady up to about 90 but what brings on a brief wobble is either sudden roads changes like bumps and wheel ruts etc. Happens rarely but I agree it's a priority.
When I used to hop off my Connie with 43mm forks and onto the stocker with fork brace, the difference was night and day when you talk high speed cornering with some bumpiness.  Even just pulling in the driveway at 5mph the difference is telling.  The brace does a fair bit, but cannot compensate for the rubbery fork stiffness of a stock Connie.  She'll ride well stock, better with a brace, totally transformed with a USD fork swap.  Just my .02

I guess it's a matter of what you're looking to get out of your bike.  If you're gonna be a hard chargin' canyon carver, you'll want a true 'sport front end', like the USD swap.
I'm quite a bit more laid back.  I didn't like the softness in the stocker front forks, so springs and emulators were good for me... maybe a fork brace someday.
If you're just cruisin'... the stock set up is more than adequate.
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