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Discussion Starter #1
Hi all,

My 2005 F4 1000S has for the second time in less than a year had a failure of the 'elastic nut' that holds the useless but decorative panels on the airbox.
First time, I came home from a longish ride and found the right side panel gone, one of the nut and bolt pairs gone (the rear one) and only the elastic nut in the front, no bolt. I guessed the front bolt worked loose and then the panel peeled off in the wind, taking the rear bolt and nut complete, but at the time I couldn't tell if perhaps the rear nut was still inside the airbox, or worse yet, gone down a throat. I had to buy all new elastic nuts (both sides) and take it to a mechanic to open it all up and check for debris in the airbox.
So, recently I bought nice glossy CF panels to replace the thermoplastic ones, and on the weekend I took both of the old panel off, no drama there, but fitting the left side first I found the rear elastic nut was a bit deformed and I had to 'realign' the internal brass threaded knurl, but it seems okay, the new CF panel seems to fitter better, snugger against the airbox.
However! When I went to the right side, the rear nut was even more deformed, the threaded bit was askew from the line of the hole, so I tried to gently align the brass knurl and instantly it just fell to pieces, one bit the outside, the other bit, with the brass threaded knurl sitting just inside the hole, as you can see in the picture below.
I tried very carefully to use a fine tweezer to grab it, but as soon as I touched it lightly it fell, INTO THE AIRBOX!!!
I am pretty sure it didn't go down the throat, but now I can't start the bike until I have had the airbox off and the elastic nut bit removed!!!!
Tank and airbox are too hard for me, I don't have the tank special tool and there's so much to undo to get there, so I have to truck it to the mechanic, after I have bought replacement elastic bolts again, only 6 months or so since the last time!
So, my questions:
1) Why was this designed like this?
2) Has anyone else had this problem, how did you solve it?
I am thinking about covering the airbox holes with duct tape, clipping two of the small hex head bolts and glueing them to the CF panel so they look okay, and then use good quality sticky-back hook and eyelet tape to stick the panel to the airbox.
475845
 

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This is a well known and documented point of concern. The well-nuts are supposed to be replaced any time you remove the panels....which is kind of overkill. BUT when they come apart that interior bit with the brass will go in the throttle and can destroy your engine. They use rubber well-nuts for vibration damping as well as easy manufacture (low tolerance screw spacing and no molded in threaded hole).

Removing the air box does not require any special tools. !! It is quite simple to do. Remove side panels (no fasteners). Remove rear seat unit (2 pins in hinge and unplug lights). Remove rear hold down bolt. Remove one side brace (3 screws) or both (I just do left side and only to allow easier access. Can be done without removing). Lift tank up at the rear and disconnect fuel pump harness, drain tubes and fuel lines (careful as the original plastic can be broken if you are rough on them). Lift tank off. Remove one bolt on steering damper and move to the side, remove key guard, remove 2 screws on either side holding air box to frame, disconnect breather hose at rear, lift air box off.

Search air box well nuts for more info. Noel recommends installing metal riv-nuts in place of the rubber well-nuts. I concur.
 

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As Ed mentions, taking off the seat, fuel tank, and airbox is not a difficult operation. It is probably a half-hour job the first time you do it.
The word of caution is: be careful exerting pressure on the fuel fittings. Push the silver lever straight in and pull straight down on the insert. Lateral pressure can sometimes snap those fittings as they are plastic.
Having a friend over to help hold up the tank while you remove those fittings the first time is beneficial.
 

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It's been well documented and linked in the maintenance stickies. Some links Search results for query: rivnut

What's interesting is that the 2005 Tamburini has threads built into the airbox above the intake side, which solves the problem, but doesn't for the rest of the F4 lineup all the way to the last model in 2009?
 

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Surfer Dave;
The wellnuts are service parts to be replaced everytime they're touched
You MUST replace the rear ones with aluminum rivnuts size M4
You can replace the fronts too, BUT YOU MUST MAKE SURE OF THE HOLE SPACING
What you need;
4 Rivnuts
Rivnut tool
2.5mm Allen wrench
You can use a Pop rivet tool but you must make a mandrel out of a 4mm bolt by filing the threads off
Here's a picture of the things you'll need
20200224_193634~2.jpg
 

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Discussion Starter #7
Thank you Gentlemen for the very useful information.
I had not heard the rivnut solution but that looks fine.
Removing the air box does not require any special tools. !!
I mentioned special tool because the workshop manual shows a special tank stand that holds the tank up while you disconnect stuff. I will try your method to see how it goes....
You MUST replace the rear ones with aluminum rivnuts size M4
Here's a picture of the things you'll need
Thanks knurl for the helpful info, will report back once done!
 

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I mentioned special tool because the workshop manual shows a special tank stand that holds the tank up while you disconnect stuff. I will try your method to see how it goes....
The "Special Tool" that I use when doing this on my own is a piece of 2X4......
 

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First the Special Tool 2x4 or metric if you prefer! (Always have a couple near your tool chest.) After tank removal, a vintage wire frame milk crate (American made) is a perfect size for support. Pad the sides with a heavy cloth and you are good to go. It can be placed on the floor or benchtop. Then work on those nuts! Afterward store that Special Tool 2x4 in it.
 

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Chuck, I think they need to import those. They're on metric.
Oh, that's right right! For the Metric Tool, I use responsibly sourced Asian Bamboo in a 50mm X 100mm X 305mm sizing.....

Instead of a Milk Crate, Vintage is a nice touch, I prefer a used rear tire with a nice fluffy garage towel on it. It is much more forgiving than that vintage plastic.
 

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Discussion Starter #13
The "Special Tool" that I use when doing this on my own is a piece of 2X4......
Ah, yes, the wooden prop. I have one of those for my RS125 tank, same deal, tilt tank and insert prop, remove connectors, then remove tank.
I probably have some 2 x 4 in the shed somewhere.
I had a look last night at the dimensions of the hole and of a full flange M4 Rivnut, seems a lot of slack there for the epoxy glue to fill.
 

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Discussion Starter #14
I looked at the thread from back around 2010/11 and @theknurl said:
Donsy;
the rivnuts i'm talking about, are alloy and work with the stock screws my suggestion for using epoxy instead of crimping is it works and i want everyone to do this

every few will have the correct tool for crimping them.....i don't, not for metric threads anyway

Cheers

Noel-theknurl
Now I'm curious because Noel's post above shows the tool for crimping, is it better to crimp them or to glue them with epoxy glue?
 

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Dave;
On some bikes uncrimped Rivnuts will touch the air horns.....
I put epoxy on them and gently crimp them......because the plastic of the airbox is so thin
You don't really need to do the fronts because they're in front of the air filter
If you do both make sure the hole spacing is correct
 

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Discussion Starter #17
Dave;
On some bikes uncrimped Rivnuts will touch the air horns.....
I put epoxy on them and gently crimp them......because the plastic of the airbox is so thin
You don't really need to do the fronts because they're in front of the air filter
If you do both make sure the hole spacing is correct
Mate thanks heaps, i've kind of worked through some of them in my head from other posts.
I just precrimped one to see how the crimper works and it fits just snug as you can see. No epoxy yet just sighting shit first. Yes I get the align the holes thing too, test fit showed that. But so far it looks sweet. The precrimped rivnut doesn't seem to touch the trumpet but vern will confirm.
 

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Discussion Starter #18
Oops forgot pic
475920
 

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Discussion Starter #19
Same spot, got mech to check airbox internals and all four now like this, quite rideable..
 

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