Has anyone here tried injecting any sort of foam into their bars as a way to dampen road buzz? I know that some of the higher end Bianchi steel road frames had a "plug" of foam that was injected into the seat tube/bottom bracket shell junction and allowed to dry as a means to dampen vibration. Was wondering if anyone had tried anything like that on their powered bikes as a means to get more comfort...
no idea, but we can certainly try! [thumbsup]
Oi!! Are you following me?
ummm, yes?
no?
if you try this, please keep us posted. i am going to give my clip ons a full riding season to get used to them, but dammit they are not very comfortable, and i am interested in anything that might help [thumbsup]
I think I might give it a shot if I can find the right sort of foam. The clip ons that came with my new bike are pretty comfy now that I have gotten the levers into a decent position (decent, not yet perfect) but there is just a lot of high frequency buzz coming through to my hands and that is what I am hoping the foam might be able to smooth off. I know that some people have used sand to dampen such frequencies, but I don't really want to go down that road...
Foam by itself probably won't do much to help. The Bianchi frames you refer to are using much thinner wall tubes. The foam used there eliminated a "ringing" of the tube itself. (The tube walls would literally be deforming, so the foam damped that motion.) Clip-ons don't ring, per se, but rather transmit, linearly, the vibration of the bike. Bar ends help because the energy of the vibration has to accelerate more mass, so the amplitude of the waves is smaller.
On the other hand, if you had some mass embedded in the foam, the energy of the vibration would be absorbed by trying to move that mass within the foam. So, if you took some Great Stuff expanding foam, and could somehow get lead shot into it while it was setting up, that would probably work very well. Expanded polyurethane like that has pretty good damping properties. You just need something for it to damp.
http://www.barsnake.com/ (http://www.barsnake.com/) I have not used this but it looks like it should work.
Quote from: Armor on May 12, 2008, 09:13:24 AM
http://www.barsnake.com/ (http://www.barsnake.com/) I have not used this but it looks like it should work.
I have used both versions of Barsnake on my I4's and have the liquid version in my "other" twin. Good stuff! I find no need for it on my S4RS strangely enough. Just diff harmonics than my "other" twin I guess. [evil]
Quote from: Armor on May 12, 2008, 09:13:24 AM
http://www.barsnake.com/ (http://www.barsnake.com/) I have not used this but it looks like it should work.
+1 on that I was trying to think of the name when this was posted.
My Ducati SS benefitted greatly from the extra weight, they were another off brand though.
On my current Monster <without clip-ons> I have the heavy throttlemeister and the all vibration was muted.
www.throttlemeister.com
Hm, why not try lead shot with bar ends? No bounce clip-ons!!
Quote from: mmakay on May 12, 2008, 04:46:51 AM
Foam by itself probably won't do much to help. The Bianchi frames you refer to are using much thinner wall tubes. The foam used there eliminated a "ringing" of the tube itself. (The tube walls would literally be deforming, so the foam damped that motion.) Clip-ons don't ring, per se, but rather transmit, linearly, the vibration of the bike. Bar ends help because the energy of the vibration has to accelerate more mass, so the amplitude of the waves is smaller.
On the other hand, if you had some mass embedded in the foam, the energy of the vibration would be absorbed by trying to move that mass within the foam. So, if you took some Great Stuff expanding foam, and could somehow get lead shot into it while it was setting up, that would probably work very well. Expanded polyurethane like that has pretty good damping properties. You just need something for it to damp.
This is a great explanation. [thumbsup]
But let me add just a little.....
Basically every substance in the world has whats called a resonant frequency, or basically a frequency that makes it vibrate. The more dense the substance the harder it is to make it vibrate and the lower the resonant frequency.
With this in mind think of a bell on the counter of your local dry cleaners. You ring the bell and it vibrates at a high pitch but if you lightly touch it with the tip of your finger the tone changes and the frequency lowers and it won't ring as long. This is a result of making the bell more dense.
The same thing happens when you ride your bike. The vibration you feel is the frequency the bike is transmitting at a given RPM and you can feel it in your hands when riding. I'm sure it feels different as the RPM's change. If you change the resonant frequency of the bars by changing it's density then it will not vibrate at the same number of cycles per second and will feel different on your hands. A higher frequency will feel annoying and buzzy and a lower frequency will go mostley un-noticed.
The idea of the "bar snake" is to lower the resonant frequency by making it more dense and giving the illusion that the vibration no longer exists.
So the short answer is adding any substance to the inside of the bars will most likely change it's properties and give you a different feel to the bars as you ride.
What I did in the past that worked really well was to use a silicone caulking and lead shot you can buy at any Dick's sporting goods in the hunting dept.
Take the lead shot and mix it with the caulking and then insert it into the hollow bar. Put some tape on one end to stop it from leaking out or use the barend weight wrapped in something and lightly tightened to allow it to be still used inside the end of the bar. Let it dry in accordance to the instructions on the tube of caulking and then remove the barend and take off whatever you used to wrap it and then re-install the bar end and you're all set to go!
Thanks for all the replies!! [beer]
I like the idea of the bar snake, but I only need it for the clip-ons on my Daytona. So with that in mind, I will most likely try the caulk solution simply because I already have some silicone caulk laying around and can get the lead shot super easy.
Thanks again guys!
Buy these, they work.
http://bontrager.com/model/04579/en (http://bontrager.com/model/04579/en)
Now that is interesting. And to think, I needed to pay the bike shop a visit in the near future anyhow.
Quote from: DRKWNG on May 12, 2008, 09:21:40 PM
Now that is interesting. And to think, I needed to pay the bike shop a visit in the near future anyhow.
If you get them, try this:
Drop your bar on the ground without them, it'll bound a lot and make a bunch of racket.
Put 'em in and drop the bar again. You'll see what I'm talking about.
I tried them in a road bike, and now they're in my monster [thumbsup]
I just used plain old #7 bird shot and filled up my clipons, worked really sweet and easy to do.
How heavy was that?
Try filling them with sand. I used onekind of glue, it worked little. But more mass in there would help more like someone sayed
Is there anything you can use that wouldn't add significant weight?
If it aint got no weight theres no wanted effect. Just loose some weight, eat carrots or take unused air out on top of the tire :P
Quote from: NAKID on May 14, 2008, 12:04:06 AM
Is there anything you can use that wouldn't add significant weight?
The "liquid" barsnake is still the best option I have used. IMHO. YRMV.
Quote from: oppet on May 14, 2008, 12:44:23 AM
If it aint got no weight theres no wanted effect. Just loose some weight, eat carrots or take unused air out on top of the tire :P
Obviously there would be SOME added weight, but I don't feel like adding 5lbs of lead into each bar.
I was thinking of something like liquid silicone caulking...
yup thats what I did. tube of glue, that feels like rubber. Little change but not much. Maybe if you get some good grips there?
Edit.. And now I would like to test sand in there, BUT I would have to get the glue out first. [bang]
For some reason I picture sand weakening the bars over time. If it can scratch glass, it can wear away aluminum fast. Lead is very soft and not abrasive at all.
My old bike had really nasty high frequency vibes. I filled the bars with a tube of silicon caulking and it made a big difference. Adding anything squishy or heavy to the inside of the bars does several things:
1) damp vibrations by being less rigid than metal bars
2) increase mass to change the harmonic frequency
3) increase mass to lower how much the bars actually vibrate.
This was on a regular set of tubular bars though, I don't know that it would do much on clipons because there's much less space to fill and they are so short and rigidly attached to the bike. As already mentioned, foam would keep them from ringing audibly but probably wouldn't do much for how they feel. If you want to try it Great Stuff is polurethand foam in a can and available at most hardware stores for about $6. Unbleievable messy before it dries.
I'd recommed either some Pro-Grip gel grips, silicon caulk or barsnake in the bars, and/or really heavy bar end weights. Not the lame little aluminmum ones, sometheing hearty like the Throttlemeister end wieght or ones off a ninja 500. Those Bontragers are really slick. Even though they're a bicycle part they'd be worth a try.
As to the weight, don't worry so much. It doesn't matter how light your bike is if it's unconfortable to ride.
Scott
Ordered some eDead last week. I was planning to pour it in my bars. Dynamat discontinued the spray can and the smallest you can get is 1 gallon for around 80. Anyone use any car audio sound deading products? results?
http://www.edesignaudio.com/product_info.php?t=3&products_id=451
Quote from: DRKWNG on May 13, 2008, 09:02:01 PM
How heavy was that?
I am not sure how heavy it actually was, i wouldn't think a whole lot more than the bar end weight.
I would have to dump out the clipon and weigh it to even guess
The vibes went to nothing though.
Quote from: RandyFloyd on May 14, 2008, 01:23:13 PM
Ordered some eDead last week. I was planning to pour it in my bars. Dynamat discontinued the spray can and the smallest you can get is 1 gallon for around 80. Anyone use any car audio sound deading products? results?
http://www.edesignaudio.com/product_info.php?t=3&products_id=451
I don't think this is going to give you the effect your hoping for. I've used the Dynamat stuff for years when I was doing high end custom car audio and it works great on a thin piece of metal like the inside skin of a door but I'm not so sure about using it for this application.
Let us know how this works out.
I would go the lead route myself. Yeah it's going to add a little weight but you'll never notice it.
Quote from: scott_araujo on May 14, 2008, 10:44:38 AM
My old bike had really nasty high frequency vibes. I filled the bars with a tube of silicon caulking and it made a big difference. Adding anything squishy or heavy to the inside of the bars does several things:
1) damp vibrations by being less rigid than metal bars
2) increase mass to change the harmonic frequency
3) increase mass to lower how much the bars actually vibrate.
This was on a regular set of tubular bars though, I don't know that it would do much on clipons because there's much less space to fill and they are so short and rigidly attached to the bike. As already mentioned, foam would keep them from ringing audibly but probably wouldn't do much for how they feel. If you want to try it Great Stuff is polurethand foam in a can and available at most hardware stores for about $6. Unbleievable messy before it dries.
I'd recommed either some Pro-Grip gel grips, silicon caulk or barsnake in the bars, and/or really heavy bar end weights. Not the lame little aluminmum ones, sometheing hearty like the Throttlemeister end wieght or ones off a ninja 500. Those Bontragers are really slick. Even though they're a bicycle part they'd be worth a try.
As to the weight, don't worry so much. It doesn't matter how light your bike is if it's unconfortable to ride.
Scott
Am having a problem with a ringing at riding speeds right at 4500-5000, was there a certain silicone you used or just everyday silicone caulk?
Using the tomaselli's on a 900SS they are lighter than the steel units and are killing me after 20 miles.
Are the Progrips that good? was hoping to get a review before ordering
Quote from: Monstermash on May 14, 2008, 10:37:30 PM
I don't think this is going to give you the effect your hoping for. I've used the Dynamat stuff for years when I was doing high end custom car audio and it works great on a thin piece of metal like the inside skin of a door but I'm not so sure about using it for this application.
Let us know how this works out.
I would go the lead route myself. Yeah it's going to add a little weight but you'll never notice it.
This got rid of most of the vibration...at idle, I can't feel a thing. At full throttle the vibration still comes through. Will get the progrip gel grips to help even more.