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Hi I am fairly new to MV. I have had my 2014 F3 800 since April. I crashed at the track on a straight after what appeared to be my rear wheel locking up during downshift. Nothing makes sense other than the slipper clutch locking up as I wasn't even to the brake marker yet, let alone the turn. There were 3 witnesses that said it appeared my rear wheel had locked up. I didn't use my rear brake, and even the dealer observed the rear brake wasn't really even operating correctly.

I'm thinking this would NOT show up on a diagnostic as an error code? Has anyone had any issues like this? I was lucky to walk away without broken bones and only a jacked up suit, bruises, a sprained neck and a headache!

Any advice would be awesome! Thanks!
 

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wouldn't the slipper clutch overide the gear box?! even if the engine sized the slipper should free the rear tire don't you think?
 

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Why were you downshifting BEFORE your braking marker? Sounds like a recipe for disaster right there.:wtf:
 

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no. The slipper clutch would not slip that much
This is an interesting contention, Geroge. The slipper in my 2010 Brutale 1090 RR will absolutely overcome a stalled engine to allow the rear to spin, so it sould overcome a locked up gearbox.

I have tested this at 65 mph tying to "bump start" my Brutatle after I shut it off to reset the tach. The slipper just let the rear spin and the engine never turned over to allow a bump start.

It was all very smooth, too.
 

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2 things 1st as per wikipedia encyclopedia "the slipper clutch can also prevent catastrophic rear wheel lock up in case of enging seizure" just google it like I did.
2nd I downshift before the braking markers.
If they had downshift markers where would they put them on the track? after the braking markers! How would that work?
 

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Did the google "testers" test a slipper on a F3 800, come on guys, no need to be fickle, try and speak from experience.

Where else do you downshift lefin, before you start braking ?

And while you're out there Googling, any idea's on how a slipper clutch get's stuck in that Wikipedia bullshit site.

If it where my bike and I know it's not rider error on my behalf, then I'd pull that motor apart and have a look at the gearbox and clutch basket.
 

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Welcome to the family.....strange crash scenario!?!

If the transmission locks up the clutch would have nothing to do with it....the clutch is between the engine and transmission, not the rear wheel and transmission. The only thing between the wheel and gear box is the chain.

If there was a gearbox malfunction to cause the rear wheel to lock it would have to be something like engaging 2 gears at the same time. A fault that would be readily evident on inspection as it is near impossible without component failure.

The slipper clutch is there to allow the transmission to override the engine during decel so engine braking doesn't cause wheel hop/lock. if you downshifted too many gears or at too high a speed and the slipper clutch wasn't there the engine braking could cause momentary wheel lock up......before the wheel speed forced the engine into over rev with possible engine damage as a result.
 

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2 things 1st as per wikipedia encyclopedia "the slipper clutch can also prevent catastrophic rear wheel lock up in case of enging seizure" just google it like I did.
2nd I downshift before the braking markers.
If they had downshift markers where would they put them on the track? after the braking markers! How would that work?
This is rather interesting. Don't the brake markers indicate when you should start braking? I think GREGOSTINI (and myself for that matter) are wondering why you would down shift before you even begin to slow down by braking.

Just an innocent query to try and understand what happened.

Kag
 

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Thinking more about this if the gear box had a problem then yes it could lock up the tire. if the engine siezed then the slipper clutch would let the tire turn free . silentservice703 tried to bump start 1090rr @65mph and the slipper clutch let it turn free. Donsy read his post.

I zigged when I should have zagged. Its early here before my 6 cups of coffee. have dr apt no eatting or drinking , dammit . I brake first and then downshift while continuing braking. My bad.

But no matter how Trixy shifted or braked it shouldn't have cause the problem, which is the answer he is looking for. gear box for sure.

Ed is it possible to engage 2 gears at the same time? Ouch
 

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I read Chuck's comment on the 1090 slipper, I'm not convinced (sorry Chuck) purely due to personal experience and I'm happy to be made the fool here lefin.

Yes you can engage two gears, and then it's called failure.

Apology excepted and understood.
 

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not trying to make fool of anyone. just understanding how this happened to Trixy and the machine better. Note to self; don't respond before coffee coffee & coffee. at least 3 cups should do.
 

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The slipper clutch I just bought for the S4Rs comes with a pin to allow bump starting...which would seem to bolster my point.
 

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there seems to be a lot of hypothesising about the cause of this lock up, how about asking is the drive line free to turn after the event !
 

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Ed is it possible to engage 2 gears at the same time? Ouch
If a free spinning gear seizes on the shaft then you could have 2 gears at once.....which immediately stops the transmission shafts from rotating (at least until the gear teeth all break off).
If a shift fork disengages from the shift drum (pin sheared off?) then you could have 2 gears at once.

In any case, yes, a catastrophic transmission failure would allow 2 gears to engage at the same time resulting in a locked up rear wheel.

But if the bike rolls freely after the crash then that probably isn't it.
 
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