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I dont know my speedometer error, but I’ve seen an indicated 92 on my stock 2018. I was not bouncing off the rev limiter yet, but I was close.
 

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Check out gearingcommander.com for mechanical limits based on sprockets and rpm, then subtract a few mph for wind resistance, tire friction, and parasitic drivetrain losses, etc.

... or fuck your speedo-healer all the way around, and you can hit 150 mph indicated on the dash at 4500 rpm, if you want. :D
 
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I dont know my speedometer error, but I’ve seen an indicated 92 on my stock 2018. I was not bouncing off the rev limiter yet, but I was close.
same here.All stock '18 and I just wanted to see what it would do, so.... and mine was about the same. between 90-91 on the dash. but mine was on the limiter... I haven't GPS'd it yet, but I would imagine it's relatively close at slower speeds and then grows as the speeds go up.
 

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same here.All stock '18 and I just wanted to see what it would do, so.... and mine was about the same. between 90-91 on the dash. but mine was on the limiter... I haven't GPS'd it yet, but I would imagine it's relatively close at slower speeds and then grows as the speeds go up.
All I need is a tire with slightly more tread on it to be 92 instead of 91.

The hard part is that things are happening fast to get a reading as you top out first gear 😳
 

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All I need is a tire with slightly more tread on it to be 92 instead of 91.

The hard part is that things are happening fast to get a reading as you top out first gear 😳
I borrowed a buddy's gopro and recorded it a couple of times to see if it was consistent each time. That was after initial break in and the first oil change. I think it had around 850 miles or so on it. So I would venture to say that there was still plenty of tread on the tire for me.
 

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Tire tread level makes zero difference to speedometer reading.
 

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Tire tread level makes zero difference to speedometer reading.
Why is that? Unless it’s GPS based I don’t see how it can not make a difference. I do agree it would only make a difference on the front or back, depending which end drives the speedo.
 

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Why is that? Unless it’s GPS based I don’t see how it can not make a difference. I do agree it would only make a difference on the front or back, depending which end drives the speedo.
It's because the ECU does not know the diameter of your rear wheel (rear wheel RPM is used for speed calculation for the SC77's).

Basically the bike's brain does not know if you have a 190/50 tire (stock diameter) or a massive 200/60 tire. It does not know how worn your tire is. The speed indicated is solely based on what gear you are in, and the rpm of the rear wheel.

Think about it like this. If you put your bike on a rear stand, and redlined it in first, it would read 91-92mph. Take the rear wheel off, dismount tire, put rim back on bike, do test again, it would read 91-92 mph. It doesn't care what's mounted to the rim.
 

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It would make a difference to actual speed, not to indicated speed on the dash.
 

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It's because the ECU does not know the diameter of your rear wheel (rear wheel RPM is used for speed calculation for the SC77's).
It's basic logic with any automotive application. The mechanical (or electronic) device used to measure speed and output that reading to your speedo does not read actual ground speed, just the number of times the stator wheel or driven gear makes a complete revolution, regardless of how large or small the wheel/tire combination is.
 

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It would make a difference to actual speed, not to indicated speed on the dash.
Correct, and that was my point. Sorry that I confused the issue by not being more specific. My bad.
 
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Ah I think it was just a misunderstanding then :).

Now what would have been great is if Honda could have gave us the ability to enter custom tire sizes and sprocket ratios into the ECU so it could correct, but instead they intentionally left that out! But that's another discussion
 
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