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Discussion Starter · #1 ·
I had an event occur yesterday that makes me think Wheelie Control is implemented differently than I'd always thought.

I generally thought that WC looked at the IMU and front wheel sensor to see when the front wheel was off the ground and would (based on the setting) limit the wheelie height and duration based on the setting.

Yesterday I was riding East of Ithaca on a stretch of road I know and love from my sports car days (fast and twisty 6-7 mile run)... I get out there rarely so wanted to have some fun. There were two sportbikes in front of me (600's or smaller) but they were either noobs or were just loafing because while they'd spurt down the straights, they were slowing to 40 on every corner - and they seemed unwilling to wave me by. There's exactly ONE passing zone, short and descending a hill. I pulled out in third to pass, accelerating from about 55 (since they were accelerating on the straight) and the front popped up. That in itself wasn't surprising - but I was in Touring mode with WC on 3 - which generally limits power wheelies (in my experience) to an inch or two quickly clamped down... yet this was a pretty substantial wheelie and I had to intervene with throttle to bring it back.

I'm wondering why... was it because I was on the apex/start of descent of a hill (you always see footage of bikes popping up over the apex of hills presumably because the road geometry already has your front end lightened). Certainly the Multi isn't normally that wheelie happy in third. If that's the case then maybe WC doesn't know as much about what's going on and just responds to detected wheelies after some short delay. Or maybe the change in the road confuses the IMU a bit too - because you're moving from flat to a downhill, the road is moving away from your front wheel so the ANGLE of a small wheelie on the flat (with respect to gravity) is now actually larger with respect to the road than it would otherwise be.
 

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Probably all of the above. You’ve certainly put a bunch of thought into it. That’s what happens when you don’t play music while you ride, you have time to think.
 

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Discussion Starter · #3 ·
Probably all of the above. You’ve certainly put a bunch of thought into it. That’s what happens when you don’t play music while you ride, you have time to think.
lol... music doesn't help, the engineer in me obsesses when something like this comes up...
 

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I think it only looks at bike position, relative to level. I don't think wheel speed would give input fast enough, plus it would have to allow for various amounts of brake pad drag friction etc. I've had the same observation cresting a smooth hill wot in 3rd, and it will allow a significant wheelie coming down(yikes!), relative to the road angle. I guess you could prove theory by trying to wheelie on a significant uphill. May not allow much, if anything. Also, my 2012 would wheelie easier in touring than sport. Always figured it made more torque down low due to intake velocity with slower throttle blade opening.
 

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possibly there was some wind lift effect on that big bike's front end once its attitude was headed skyward that enhanced the lofting once set in motion. Electronics would be slow to halt the upward inertial force unless they actuate the rear brake - which is not likely. A headwind would accentuate the lift as well. THink I'd crank up the anti-wheelie setting if you rely on it to moderate your throttle control.
 

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Unless the 'brains' know where the suspension is in its travel, and how fast it's changing, there is far less info to makes decisions with. The gyro only gives part of the story and, as you've already explained, the road was falling away from what WAS 'level'. Though I do not know, I would guess there is no suspension position sensor in the fork. Anyone???
 

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Unless the 'brains' know where the suspension is in its travel, and how fast it's changing, there is far less info to makes decisions with. The gyro only gives part of the story and, as you've already explained, the road was falling away from what WAS 'level'. Though I do not know, I would guess there is no suspension position sensor in the fork. Anyone???
I haven't seen anywhere in the wiring diagrams that there is an actual positional sensor on the front forks.

I've had the opposite instance happen to what DaveK described. I was heading up a road that had a very sharp hairpin in it. As I tipped the bike in and started to apply throttle to get through the turn, the bike suddenly cut the throttle on me. I assume it was the DWC that noticed the increase in angle along with the increase in throttle and thought it was a wheelie.

So I think it only looks at rate of pitch and throttle position to determine if the bike is starting to wheelie.
 

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My experience with DWC on my DVT was that it was useless in the areas I ride, ie steep tight mountains/hills
When climbing steep hairpin sections (1st or 2nd gear) it would always cut power half way through no matter what it was set at
Interesting though, my new 1260 does not intervene in the same situation, and I have now left it on. I'm guessing the DWC is considerably more advanced and is now usable
Another thing even more surprising is that I find the 1260 in these tight sections actually more nimble and quicker steering than my old DVT, still cant get my head around that yet, as I was expecting the opposite
 

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Discussion Starter · #9 ·
Hmm I've never had wc intervention be so blatant that I actually felt it. I've got some steep parts of some of my rides and while I know some combo of tc/wc was active because the front stayed planted... there was no feeling of power loss. On uphill hard accel runs (like expressway onramps) the bike will (in touring mode) gently lift the front in second under heavy throttle (full throttle generally will light the TC warning) and after 50 or 75 feet set it back down. In sport mode the front will come up quicker and stay up... but neither mode has any feeling of power getting cut (unless the TC lights up).
 

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Dave
It takes a combination of tight corners and steep a climb rate at the same time to trigger what I'm referring to.

I'm guessing the DWC has a much stricter set of configurations when the bike is lent over. All I know is when I shut off DWC all was fine

But as previously stated, its all irrelevant to me now as it works properly on the 1260
 

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Discussion Starter · #11 ·
I've got someplace where I can try it... though I usually take it easy through there (extreme grade with very tight corners... called "the winding stair").
 

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Interesting thought. If your going down hill on a pretty good grade, how does the IMU know this? And if it didn't, you could be in a wheelie with the bike level relative to the horizon. If the IMU thinks your still level, it wouldn't interfere.

I don't think I've ever had the occasion to go WOT on a steep downhill so would never have encountered this possible scenario.
 
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