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I've spent the last three or so months going through the various sections, moving posts into the various "new" sections we have, and have come across a few hub failures which are not on your lists Mitch, looks like I'll have to keep a tab on them and let you know.
Bugger......more work.��
 

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Discussion Starter #3
Sorry mate,you will have to go back and find them for me.:jsm:
 

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Sorry to hear about the failure.I have commented on the Hub Failure thread.
 

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Ah....last of the original hub design.... Sorry it failed.... you must not have been following Noel's torque specs on the pinch bolts !!:nerd:
 

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Well I guess you can put me on the list Mitch. 2nd generation design with 2 roller bearings and one ball bearing, and crap sprocket carrier rubbers.
61000km, and it hasn’t actually failed, but I can feel a wobble on the rear wheel. Stripped down there is no obvious failure. No end float, no grooves that says the spacers are worn, no loose sprocket or wheel nut. The bearings clean up nicely, no rough spots. No signs of chatter on the axle or inner spacers that run between that and the roller bearings. Don’t own a micrometer, so I cannot measure the components to see which piece has worn.
Decision time. Rebuild the hub or replace with a Mitchy hub? Going to ring around for prices etc of a bearing and seal set.
To be continued....
 

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Ok, stripped the hub down and the needle bearings is where the slop is occurring. I have ordered the bearings and seals to come from Applied Industrial Technologies, who are a distributor for skf and others. They are in stock in Melbourne.
In the meantime I will now attack the 3 pin plug between the alternator and the regulator, which has been cooked. Very tempted to solder that. Very rare that I have had to unplug it.
 

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Very unusual for needle bearings to wear Jon.
Especially with 2 of them there on the later hub.
Were the bearings dry?
Glad you are sorted with the parts.
 

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Definitely not dry. Cleaned and repacked with lithium grease every 6000km, when I do a service. Chain never tight, pinch bolts done to spec. No signs of heat or rust.
Will be interesting when I get to put it back together. I have usually found the spacers to be an easy slide fit, and the axle to be a little more work.
Once I had the roller bearings out and slid them over the spacers, there was visible slop. I was quite surprised. I presume it was hidden somewhat when the sprocket and wheel nuts get torqued up.

The oem bearings and seals are branded INA by the way.
 

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In the meantime I will now attack the 3 pin plug between the alternator and the regulator, which has been cooked. Very tempted to solder that. Very rare that I have had to unplug it.
A lot of voltage/current going through those 3 wires !!! Any slight looseness and/or corrosion results in resistance = heat. Common problem on a lot of bikes dating way back. (I've seen lot's of old Hondas and Yamahas with this problem).

Replacement parts are available.... these guys sell what you need for very fair prices:

Motorcycle Terminals, Connectors, and Wiring Accessories
 

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All back together. Road test this weekend, weather permitting.

Omitted to mention to the other half that I used the oven to heat the hub before pressing the bearings back in...
 

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Road tested excellent :)

After thinking about it, I think the root cause was having the chain too tight. I always check with the rear wheel unloaded. I was setting the chain at 55mm at full droop. As the suspension works the chain gets more tight. When I checked it with static sag it comes up at 50mm. So as the suspension works to full stroke on our shit roads I think the chain was getting even more tight.

Increased chain slack to 58mm at full droop. Now all happy.
 

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Droopy is happy days on a MV Jon.:wink2:
 

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you can add me aswell! 16500KM Hub was damaged like the dealer told me, he couldnt fit the spacers and even the bearings back in cause the hub was deformed? Brutale 800 2015

i now ride a design corse hub cause the original mv part wasnt available at that time
 

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That is low mileage for a new style hub to fail.
Was the hub serviced at 12000kms?
 

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As a preventative measure, I took the hub on my 2004 SR apart and checkked and regreased at around 22.000 kms.
Before that I changed the chain and sprockets at around 18.000 km, and torqued the pinch bolts to what was stated in the manual.. I have little doubt that the previous owners have all done the same, and the hub, bearings and axle looked very good, actually better than most the images I have seen on the forum, from bikes with comparable mileages.
This leads me to believe that manufacturing tolerances in both hubs and perhaps especially the swingarm has a huge influence on wether or not the torque applied to the pinch bolts is the main culprit for hub failure. Certainly a lower (safer) torque will hold the hub in place, so better safe than sorry. -- I have backed the Torque off slightly, like "the forum curmudgeon" is never late to point out ..;)
Even though some people think so, engineering and applied mechanical design is not an absolute science, compromises always have to be made, changing the process more towards art than science. The single-sided swingarm of the MV's were always more art and design, than solid, bulletproof mechanical design..
The original F4 ORO was very close to "State of the Art" in 1997-99 when it was designed, and transforming its esoteric materials (how many kilogrammes of magnesium- replaced with aluminium - how much 1.1 mm thick Carbonfibre replaced by 3,5 mm ABS plastic .. and steel for the tank) The difference in load and forces on the hub and bearings, just from the increase in unsprung mass of the rear-wheel setup? ---
 
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