Windshield wobbles while braking - 600RR.net
Troubleshooting Having trouble with your bike? Common know issues or trobuleshooting questions here.

 
LinkBack Thread Tools
post #1 of 12 (permalink) Old 09-12-2018, 03:13 PM Thread Starter
Training Wheel Hero
 
Plamen's Avatar
 
Join Date: May 2018
Posts: 6
Thanks: 0
Thanked 1 Time in 1 Post
Feedback Score: 0 reviews
Windshield wobbles while braking

Hi colleagues.
I hope someone of you may give me an idea what is the problem with my bike. It is the 2004 Honda CBR 600 RR and the issue is the following: let’s say I am riding with 150 km/h and then I brake, when the speed decrease to 95 km/h the windshield starts to wobble, then at 75 it stops and starts again when speed is 40, and it stops again in 25 and is missing till 0. The trebling is very fast and it is only on the windshield, the range of moving is about 2-3 centimeters, up and down. The levers and the handlebars are not shaking at all, I don’t see it and I don’t feel it on my hands and fingers. The problem started in 2017 and I am not sure why it started. My tires are new, front is 0617 with 4*000 km on it, pads are new, I’ve changed the bearings on the steering wheel (no slacks on it), the bearings on the front wheel, I’ve serviced the forks, the suspension settings are standard, I’ve been riding with 3 different pairs of front discs (not new ones) and it does the same wobbling with each of them. The braking calipers are serviced and there is no leakage, nor signs of damage. Both rims have small curves (1 on the front and 1 on the rear) but when riding even 180+ km/h there is no problem, no shaking.
Any idea what may cause this wobble ?
Plamen is offline  
Sponsored Links
Advertisement
 
post #2 of 12 (permalink) Old 09-12-2018, 06:59 PM
Pocketbike Racer
 
Wazoo's Avatar
 
Join Date: Sep 2018
Location: Windsor, CT
Posts: 304
Thanks: 151
Thanked 66 Times in 61 Posts
Feedback Score: 0 reviews
Did you by any chance add something that changed the aerodynamics of your bike when this started happening? Tailbag, saddlebags, different plastics, etc? It sounds like your going in and out of the natural frequency of the part. Is it OEM? if it's OEM, look for loose fasteners. If no loose fasteners, or it's an aftermarket windscreen, do a test to find out if it's a resonance at the natural frequency; get some non residue tape and apply it along the edges of the windscreen to attach it to the fairing, this will change the natural frequency of the part. If the resonance goes away, then it's the effect of the natural frequency of the windscreen. You could maybe add some sort of a dampener (washers) to a couple of the fasteners. As a alternative test, you could just get the resonance going, then put your fingers on the windscreen to see if that makes it go away. If it does, then same thing, it's the effect of the natural frequency of the windscreen. Add something like washers (so they're in contact with the windscreen) under the fasteners to change the natural frequency of the windscreen. If the resonance doesn't stop when you add tape, put your fingers on it, or add dampening washers, idk. Good luck.
Wazoo is offline  
The Following User Says Thank You to Wazoo For This Useful Post:
dixon cider (09-14-2018)
post #3 of 12 (permalink) Old 09-13-2018, 01:38 AM
Moto GP Racer
 
Join Date: Feb 2009
Location: Paradise of C. Cali
Posts: 4,835
Thanks: 1,029
Thanked 660 Times in 616 Posts
Feedback Score: 1 reviews
Did this start to happen only recently?

OE windscreen?

No shaking of handlebars?

Maybe, try another profile windscreen?
tary preisser is offline  
 
post #4 of 12 (permalink) Old 09-13-2018, 02:19 PM Thread Starter
Training Wheel Hero
 
Plamen's Avatar
 
Join Date: May 2018
Posts: 6
Thanks: 0
Thanked 1 Time in 1 Post
Feedback Score: 0 reviews
Nothing added. No bags or such. I added crash pads, but they are tightened well and I don't think this can be the reason. Also balancers on the handlebars but they should help, not cause problems! The windshield is aftermarket double bubble but at the very beginning when I bought the bike there was no problem with it. I may try to change something on the fasteners of the windshield or try another one or remove it for test. But I still wonder what may cause this. The windshield is part of the front fairing, it is caught for the frame of the bike and my logic is that for some reason the body is shaking. I first thought it is a mechanical problem and that's why I changed all bearings and spent all these money. But honestly this bothers me every day. Thank you for your suggestions !
Plamen is offline  
post #5 of 12 (permalink) Old 09-13-2018, 09:25 PM
Moto GP Racer
 
Join Date: Feb 2009
Location: Paradise of C. Cali
Posts: 4,835
Thanks: 1,029
Thanked 660 Times in 616 Posts
Feedback Score: 1 reviews
Maybe the well nuts that fasten windscreen are dry and shrunken?
tary preisser is offline  
The Following User Says Thank You to tary preisser For This Useful Post:
dixon cider (09-14-2018)
post #6 of 12 (permalink) Old 09-14-2018, 05:23 PM
Pocketbike Racer
 
Join Date: Sep 2017
Location: USA
Posts: 382
Thanks: 36
Thanked 99 Times in 87 Posts
Feedback Score: 0 reviews
Check the bolts for your mirrors, other than that, try reinstalling your windscreen, and then front cowling.
Axel Nut is offline  
The Following User Says Thank You to Axel Nut For This Useful Post:
dixon cider (09-14-2018)
post #7 of 12 (permalink) Old 09-17-2018, 02:17 PM Thread Starter
Training Wheel Hero
 
Plamen's Avatar
 
Join Date: May 2018
Posts: 6
Thanks: 0
Thanked 1 Time in 1 Post
Feedback Score: 0 reviews
The windshield nuts are new, I tightened them as much as possible. Also I have changed 3 different types. Now I put washers on the mirrors but no charge. I folded the mirrors in order to change airflow on the bike - no change. Removed the balancers on the handlebars but nothing. When touching the windshield the treble stops. I will replace the crash pads with the original bolts to see if any change. Also I will remove the plates that cover the brake pads and try with low speed to see the behaviour. (Know this is risky !) Keep thinking it's something on the calipers but it should be something really tricky to find. Maybe something like not a smooth work of the cylinders, but I don't feel a push back on the brake lever. 😞
Plamen is offline  
post #8 of 12 (permalink) Old 09-17-2018, 07:15 PM
World Superbike Racer
 
Miweber929's Avatar
 
Join Date: Mar 2013
Location: Woodbury, MN
Posts: 1,957
Thanks: 199
Thanked 563 Times in 444 Posts
Feedback Score: 1 reviews
How solid is your upper cowl mount? Could that be damaged, loose or cracked?

- '17 Ducati Supersport S
- '13 Kymco Super 8 150
- '11 Triumph Sprint GT
- '10 Yamaha WR250R
- Past rides: too many to list
Miweber929 is offline  
The Following User Says Thank You to Miweber929 For This Useful Post:
dixon cider (09-17-2018)
post #9 of 12 (permalink) Old 10-15-2018, 12:37 PM Thread Starter
Training Wheel Hero
 
Plamen's Avatar
 
Join Date: May 2018
Posts: 6
Thanks: 0
Thanked 1 Time in 1 Post
Feedback Score: 0 reviews
Just to share the reason for my problem. It was the crash pads, their bolts.... . The hint for the resonance was helpful. Thanks! Today I tried to tighten them and the bolts made 1-2 turns until they were tight enough. I made a test ride and there was no wobble. I love my bike again 😉
Plamen is offline  
The Following User Says Thank You to Plamen For This Useful Post:
dixon cider (10-16-2018)
post #10 of 12 (permalink) Old 10-15-2018, 01:08 PM
Pocketbike Racer
 
Wazoo's Avatar
 
Join Date: Sep 2018
Location: Windsor, CT
Posts: 304
Thanks: 151
Thanked 66 Times in 61 Posts
Feedback Score: 0 reviews
Quote:
Originally Posted by Plamen View Post
Just to share the reason for my problem. It was the crash pads, their bolts.... . The hint for the resonance was helpful. Thanks! Today I tried to tighten them and the bolts made 1-2 turns until they were tight enough. I made a test ride and there was no wobble. I love my bike again
What "crash pads"? Frame sliders? So the upper engine mount bolts? If yes, they should be TORQUED to 40 lb-ft. Not just tightened.
Glad you found it.
Wazoo is offline  
post #11 of 12 (permalink) Old 10-15-2018, 03:35 PM Thread Starter
Training Wheel Hero
 
Plamen's Avatar
 
Join Date: May 2018
Posts: 6
Thanks: 0
Thanked 1 Time in 1 Post
Feedback Score: 0 reviews
Yes. Frame sliders. I don't have such wrench so I just tightened them as much as I could. The good is that I found the reason. Next season I may torque them to the specified value. This problem was tearing my nerves every day for the last two years. I never thought this could be the reason. A big load is now off my back :))) I changed steering bearings and front wheel bearings and braking disks...but just had to tighten 2 bolts instead. Mad story!
Plamen is offline  
post #12 of 12 (permalink) Old 10-15-2018, 10:35 PM
Pocketbike Racer
 
Wazoo's Avatar
 
Join Date: Sep 2018
Location: Windsor, CT
Posts: 304
Thanks: 151
Thanked 66 Times in 61 Posts
Feedback Score: 0 reviews
You should get a torque wrench. I have (3), 1/4", 3/8", and 1/2" drive. They aren't cheap, so I'd start with the 3/8" drive size as it will cover most of your torque requirements. You may have tightened them the 1st time, but if they weren't torqued enough, they can loosen up. The other scenario is similar, if you overtighten them, the bolt can yield, and then it can loosen up because the bolt material has yielded. In this case, you would need a new bolt. There are torque requirements for all bolts, but some bolts are critical. If it's critical, it's called out in the engine manual, If less than critical, use a standard torque chart to get the value. An engine mount bolt is one of these critical ones, as you have experienced.
Wazoo is offline  
The Following User Says Thank You to Wazoo For This Useful Post:
dixon cider (10-16-2018)
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the 600RR.net forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome