Windshield bolts: scary ride yesterday

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henwil

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Tracy, CA
Hi Folks!

Yesterday I had a very nervous ride home from work. It is about 25 miles mostly through the Altamont hills and early on I noticed the wind noise sounding different than usual. When I looked at the windshield I could see only one bolt still holding the windshield on the left. I did not have any extra bolts or duct tape with me, so I just kept going keeping the speed low. When I got home a cold shiver went through me when I realized that only one of the six bolts still had a head on it! That was close :(

So the question is why? I have a rifle windshield and it is the original bolts that was on the stock windshield. I removed the foam tape that was on the rifle blocks (it was damaged after buying the windshield used) and replaced it with six rubber washers that are less than 1mm thick.

I have also moved to CA four months ago so thermal cycling comes to mind, but probably not the reason (?)

I will get some nylon bolts at ACE or OSH today if they have them in metric, with some extras to keep on the bike. Probably also foam tape that are several mm thick to use in place of the washers.

Any thoughts/inputs appreciated :)

Thanks!

 
Hi Folks!When I looked at the windshield I could see only one bolt still holding the windshield on the left. I did not have any extra bolts or duct tape with me, so I just kept going keeping the speed low. When I got home a cold shiver went through me when I realized that only one of the six bolts still had a head on it! That was close
sad.png


So the question is why? I have a rifle windshield and it is the original bolts that was on the stock windshield. I removed the foam tape that was on the rifle blocks (it was damaged after buying the windshield used) and replaced it with six rubber washers that are less than 1mm thick. I have also moved to CA four months ago so thermal cycling comes to mind, but probably not the reason (?)

I will get some nylon bolts at ACE or OSH today if they have them in metric, with some extras to keep on the bike. Probably also foam tape that are several mm thick to use in place of the washers.

Any thoughts/inputs appreciated
smile.png
Thanks!
Henwil,

I would get the OEM bolts in there, as soon as possible. They are designed to break off in an impact, which is a safety provision. Those generic Nylon bolts may work as a temporary stopgap measure (until you get the right OEM bolts in hand), but they may not be safe enough, also.. Keep the Nylon bolts as spares in the tool bag, then.

I can imagine two or three reasons for the failure of the old bolts. Over-tightening the bolts could be one cause. Rock strikes or bird strikes could also crack or break some of the bolts, with others breaking later. Loss of the foam tape would also cause harder road shocks at the bolts, because the foam is cushioning. Any of these reasons may combine together, of course. I don't know what foam tape Rifle uses, but if it is white foam, you can get that tape in several thicknesses at office supply stores. Otherwise, get some (or a source) of the correct tape from Rifle. Rubber washers may not be a good replacement, there.

Infrared

 
It's important to check these nylon screws at each oil change. They will, somehow, sometimes, get a little loose and periodic snugging is in order. So the oil change interval is a good time to take a few minutes and check them for soundness. Screw em in good and firm, but not overly tight.

I see no reason why nylon replacements from another source will not work just fine. Nylon is nylon. I have heard the ole "they are supposed to break off in a crash" **** for years. I don't buy that at reason for the nylon fasteners. It's my opinion they are in there instead of metallic screws to prevent hole fracture of the shield material.

 
The screws should go in just snug. If overtightened, the heads will break off - while riding, not while tightening unless to go way too far.

 
........ Over-tightening the bolts could be one cause..........
This. When installing them, when they touch, stop tightening. There is no extra tug for extra tension, as that extra tension will pop them.

I see no reason why nylon replacements from another source will not work just fine. Nylon is nylon. I have heard the ole "they are supposed to break off in a crash" **** for years. I don't buy that at reason for the nylon fasteners. It's my opinion they are in there instead of metallic screws to prevent hole fracture of the shield material.
Once you have a hole fracture, you have a crack, which is a fracture point if there's a rider/windshield impact, and the edge of that fracture point becomes a cutting edge. So even if your premise were the only reason, it's still a valid reason.

But if you go through that windshield, or hit a pedestrian or animal that comes to you through the windshield, you want it to break off whole and not fragment into cutting blades.





As an aside, a coworker came up to me one day several years ago and told me he broke my windshield off. He was afraid he was gonna be into me for hundreds of dollars, but fessed up anyway. He had a backpack slung over his shoulder but not quite behind him and walked by the bike and snagged the shield with the pack. All seven bolts snapped cleanly and the shield hit the ground rider-side down so it didn't get scratched up. All I had to do was run get some screws and all was well. I am sure that metal bolts would have resulted in the shield or the mount, or some of each, being broken.

 
Not having a FJR, the idea of nylon fasteners for the windshield surprised me a bit and piqued my interest. The ST1300 has metal flange bolts through a metal, shaped collar; the collar fits into a shaped 'plastic retainer', that retainer fits into the hole through the windshield--4 total fasteners. That design is such that there's no metal touching the windshield.

As I read a bit about 'nylon', it became apparent that there are many types of nylons (https://en.wikipedia.org/wiki/Nylon). But the point that caught my attention is that nylons are hygroscopic (absorb water), and therefore can change dimension. I suspect that is the reason why folks can find them loose on occasion. As they change dimension and you have to retighten them, they're slowly stretching. Perhaps they'll eventually break from this??

As there are different types of nylons, I'd buy OEM replacements, if I were replacing those fasteners. But I wouldn't hesitate to use an alternate sourced nylon screw on the interim.

smile.png


 
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L/C Joe - thanks for the heads up on checking these screws. A month ago, when I installed my Cee Bailey W/S, he instructions said "3 ft pds" - uh... yeah, I don't have that torque wrench handy. So I went until "snug", and called it good. Yesterday, after reading your thread, I checked and 3 of the screws were less than hand tight. This time, I went a 1/4 turn past "snug" and we will continue to monitor it.

 
Thanks for all the input!

I discovered the nylon screws that came with the Rifle windshield and installed those for now. I made sure not to over tighten them.

I will definitely now be monitoring these screws periodically to make sure they are still tight, and more importantly that there are no missing heads. At least at every oil change, which is a good idea.

 
I keep a set of OEM screws on hand. I've noticed both loose screws and stretched screws when removing my windscreen for maintenance. You can tell the stretched ones by the black nylon turning white in those areas. Those always get replaced with new.

 
I replaced mine with windshield mounting screws from a Kawasaki Concours (stainless steel):



Never in all my motorcycling life heard of any hazard as far as mounting a windshield with these bolts. Twenty years of C10 Concours production, not one incident that I have seen reported.

I don't want the shield to cave in if I hit a bird (not an unlikely event). I have heard of screws breaking such as the OP (on more than one occasion). I'll take the chance of the steel screws.

Dan

 
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I replaced mine with windshield mounting screws from a Kawasaki Concours (stainless steel):


Never in all my motorcycling life heard of any hazard as far as mounting a windshield with these bolts. Twenty years of C10 Concours production, not one incident that I have seen reported.

I don't want the shield to cave in if I hit a bird (not an unlikely event). I have heard of screws breaking such as the OP (on more than one occasion). I'll take the chance of the steel screws.

Dan
Agreed. I've seen both nylon and steel mounting hardware in OEM shields and aftermarket. My GL1200 shield mounted with steel, as did all the National Cycle shields I've used. The Rifle Sport fairings I've had on three bikes came with nylon screws and nuts. The CalSci XL shield for my Feej came with stainless steel screws; if that's what CalSci feels is appropriate to handle the additional wind load, I'll feel safer with their stainless hardware. Of course, if I do get decapitated from being thrown into the edge of the shield, you're all welcome to tell me "I told you so",,,

 
By installing an oversize windshield like the Rifle (or my Cee Bailey) you have gone outside the design spec that the break-away screws are supposed to hold. Add a Laminar lip, Rifle Block or other accessory and it just gets worse. I use metal screws to hold the windshield on and as an adult accept the risk (if any) that imposes. Having a windshield fly off unexpectedly seems like a more likely problem, than worrying if you might hit it if/when you crash. Nothing good can come of a wreck that sends you through that shield, breakaway or not.

 
My V-Stream is held on by either stainless steel or aluminum fasteners with plastic washers. It was on the bike when I bought it, so I'm not sure if they came with the new screen or not.

 
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I use the stock nylon screws with stock, stock touring, and Cee Bailey barn door shields. Careful not to overtighten. No problems up to redacted mph. Yet...OP- glad you caught it in time.

 
I'll put money on over tightening as the primary cause of popped heads on those screws. It wouldn't take much torque to damage those nylon screws. I use finger tips only on the screwdriver when tightening those screws and am still using the original screws after almost 8 years and over 100,000 miles (and I use a large Vstream shield for most of the year which should put a pretty good load on the screws at high speeds). Never had any screws come loose either between shield changes that happen 2 or 3 times each year.

 
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