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Discussion Starter #1
I got a PM from someone offering me a top cowl today for the project - sounded like he's got the same problem I have had twice.

I don't know if anybody here's had the same problem occur where the top screw mounts on the front cowl get cracks in, which spread quickly once they start. I'm about to order my 3rd top cowl, even though the bike's never been down! :eek:

So there has to be a solution to this. One possibility I thought of would be to find suitable shoulder washers similar this as an example. but preferably in stainless steel: http://www.hobbyparts.com.au/store/partslist/washersshouldernylon/washersshouldernylon/all/1/

I'd drill the holes slightly larger to fit the shoulder washers - which should have inserts of much the same thickness as the panel, with a thin nylon washer on the paintwork side - for added protection. I reckon this would give the panels a little added strength and hopefully stop it happening again.

If the correct sized shoulder washers are too difficult to find (Have searched online, but found nothing so far...) another possible alternative could be to get some rubber washers & glue behind each mounting hole. This would add a bit of cushioning and hopefully cause less stress to the panel. If I can't get the first solution, the rubber washers may be plan B.

Has anybody else had the same problem & can any of you offer any help in where I could find such shoulder washers?

Also, any other possible solutions you can think of and add would be appreciated.

I'll buy the new top cowl soon, but I'd be dissappointed if a year or so down the road the same happens a 3rd time!
 

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I totally agree that is a pretty darn good idea. I have a bunch of washers like that and never thought to try it out.

When I first noticed it on my bike I went to teh toolbox and grabbed a rubber washer and put it between the plastic and the metal mount, mine was cracked already so I can't tell you it helped, but the crack never spread until some asshat knocked the bike over.

There are other parts of the body work that use shoulder bolts (with the built in spacer) like on the lower part of the fairing and the rear fairing between the legs so maybe thats a potential use as well?

It just seems there could have been a much more solid mounting system for the upper fairing- it really only has three, two sides and the front, the rest is attached to something that flexes.


I can't wait for my Sharkskinz....mainly because it gets rid of the 6 upper fairing bolts and their damn tube nuts!!!
 

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Discussion Starter #3
Hmm another possibility... Drill holes slightly larger and use the spare little plastic spacer collars that come with Probolt kits for where original M5 sized collar bolts go.
Then for good measure also add a rubber washer underneath.

I reckon that would cure the problem once & for all..

First time I thought it was just a weak top cowl, or it had been stressed before I bought the bike. 2nd time was dissapointing. Kinda determined this isn't going to happen to me a 3rd time...
 

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I got a PM from someone offering me a top cowl today for the project - sounded like he's got the same problem I have had twice.

I don't know if anybody here's had the same problem occur where the top screw mounts on the front cowl get cracks in, which spread quickly once they start. I'm about to order my 3rd top cowl, even though the bike's never been down! :eek:

So there has to be a solution to this. One possibility I thought of would be to find suitable shoulder washers similar this as an example. but preferably in stainless steel: http://www.hobbyparts.com.au/store/partslist/washersshouldernylon/washersshouldernylon/all/1/

I'd drill the holes slightly larger to fit the shoulder washers - which should have inserts of much the same thickness as the panel, with a thin nylon washer on the paintwork side - for added protection. I reckon this would give the panels a little added strength and hopefully stop it happening again.

If the correct sized shoulder washers are too difficult to find (Have searched online, but found nothing so far...) another possible alternative could be to get some rubber washers & glue behind each mounting hole. This would add a bit of cushioning and hopefully cause less stress to the panel. If I can't get the first solution, the rubber washers may be plan B.

Has anybody else had the same problem & can any of you offer any help in where I could find such shoulder washers?

Also, any other possible solutions you can think of and add would be appreciated.

I'll buy the new top cowl soon, but I'd be dissappointed if a year or so down the road the same happens a 3rd time!
When we discussed this before we came to the conclusion that the nylon (or some sort of washer) would probably be the best solution, if we could find one to fit. FYI: Motorbike fairings are typically made of ABS plastics as it offers great properties in impact resistance, toughness and is one of the best surface finishes in plastics mouldings. Two main reasons why this is perhaps happening:
1: at high vibrations and for prolonged periods the metal screw is rubbing on the ABS and causing it to become brittle and then finally crack. To solve this from happening we can attach a nylon washer that allows the metal screw to rub on the nylon not the ABS.
2:the area around the screw hole is two small and has no plastic supporting bosses (ribs) therefore it flexes a lot at sustained air pressure and cracks. You can stop this from happening by bonding something more rigid (perhaps carbon) to the underside area around the hole, say 10cm x 10cm square.

I'll keep thinking for more solutions!...HTH



Sent from Motorcycle.com Free App
 

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Discussion Starter #5
Thanks buddy. This is right down your street, so I guess you'll work out the best solution - then we can share it with people on here. :)

Hang on... 10cm x 10cm or is that a typo?

Wouldn't be too difficult to bond some weave under the panel for strength I guess?
 

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Have the same problem.

I have the same problem, as I am sure many do. Spoke to an RC owner I met from NYC who told me the same thing. Also there is a bike shop in the Bronx, the owner has an RC of his own. He told me that he had his repaired. Don't know much more about it but was wondering if anyone else has had them repaired or just replaced the upper?
 

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Bonding a small peice of carbon under there isn't a bad idea either...

You would directly bond it to some scuffed up body work...you could even get away with some FG mat. That would be a pretty simple fix and wouldn't be visible. This would also keep from further weakening the area by drilling the mounting hole larger for the fastener.
 

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Discussion Starter #8 (Edited)
Quick sketch from Carlos to show what he meant.

"Hi buddy, I meant 10cm x 10cm, obviously not exactly it would need to be cut!"

 
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