Wildguzzi.com
General Category => General Discussion => Topic started by: twowheeladdict on August 24, 2025, 08:17:33 AM
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This happened to an acquaintance of mine more than once when riding aggressively in the Smoky Mountains.
The scenario.
He was running the curves and thought he needed to downshift to make a pass. When he downshifted, the RPMs jumped into the red, but instead of banging off the Rev limiter the bike shut off.
He had to turn the ignition off and back on to recycle the system and wait for boot up before he could restart the bike.
Like I said, it happened more than once and the loss of power meant aborting the pass and added to the danger he already put himself in.
Thoughts? Normal? Or did he find a scenario the engineers didn't anticipate?
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The rev limiter will retard the timing and or shut off the fuel to the motor to protect it. Over revving via downshifting is bad juju. You're talking about mechanical over over reving, and that's how things break. Perhaps the ECU is programmed to shut down the motor to protect it?
Tell your buddy to stop downshifting that deep.
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Maybe the moto gods are looking down on your friend and telling him to ride differently.
My 2020 V85TT revs very fast and hits 7200 R's I have to watch it very closely under hard acceleration or the rev limiter kicks in. I have never had the bike shut down. I also don't downshift to accelerate, I just roll on the throttle. But I also pass when I don't see on coming traffic. These bikes are not speed demons.
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Probably help if he adjusted the rev limiter to as high as it will go. Not sure what that is. I think mine came set at 4000 or 4500 and I raised it 6500. I see the light blinking on occasion on acceleration but its never shut the motor off.
BTW Pretty sure the red light does not correspond to the rev limiter more just like a point on a tach.
Pete
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Probably help if he adjusted the rev limiter to as high as it will go. Not sure what that is. I think mine came set at 4000 or 4500 and I raised it 6500. I see the light blinking on occasion on acceleration but its never shut the motor off.
BTW Pretty sure the red light does not correspond to the rev limiter more just like a point on a tach.
Pete
Wouldn't help, he is over revving from downshifting. Thats inertia and mechanical. Probably double bad if the motor is not broken in. I've seen guys blow their motors apart (cars) from over rev on downshift.
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Wait? You can adjust the REV LIMITER? Are you guys sure it's not just the shift warning light? I can't imagine they would make the limiter itself adjustable.
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Rev limiter can not be adjusted by a mere mortal. One of the new fangled computer programs can do it. Has he installed one? I've had four different V85's from 2020-2025. All just kill the RPM but sure souldn't kill the engine. He needs to go to a dealer and hook it up to PADS. It sounds like a bad ECU to me.
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Rev limiter can not be adjusted by a mere mortal. One of the new fangled computer programs can do it.
This is correct, the only setting we have access to on the dash is the shift light RPM.
Wouldn't help, he is over revving from downshifting. Thats inertia and mechanical. Probably double bad if the motor is not broken in. I've seen guys blow their motors apart (cars) from over rev on downshift.
Not sure how everyone is missing this. If OP's friend is downshifting like that, he's essentially "money-shifting" the bike and mechanically over revving the valve train and will likely encounter valve float etc.
It wouldn't surprise me if the ECU is set to turn the bike off when over revved in an attempt to save the bike. There is likely also a flag in the ECU that counts the number of mechanical over-revs, and some will record the amount of time spent in different RPM ranges as well.
Tell your friend to be a bit gentler on the bike or to get a supersport with a much higher redline.
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I guess I have a problem thinking someone is so dense they are downshifting THAT MUCH or that poorly
I mean, I ride smallblocks, so I can't just roll on for most passes. I have to bang it down a gear, once in a while two. But I can never on my life recall downshifting so much it bangs off the rev limiter.
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If the motor physically higher rpm than the map there is no data & will shut off, that's my idea. I know of no one that has been in this situation.
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If the motor physically higher rpm than the map there is no data & will shut off, that's my idea. I know of no one that has been in this situation.
If this is the case, sounds like he is lucky and should thank Guzzi (or Piaggio) for thinking ahead for him. I'm not a big fan of that "Nanny" kind of stuff but ...
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Part of his problem may come from multi-bike syndrome, and the fact he was riding with guys on more powerful, higher revving bikes.
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To quote Clint Eastwood: "A man's gotta know his limitations........ ............".