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I have tried many different gearing setups on the track and I have the PCV with the rev extend and there is definitely a speed limiter built in at 110 mph.
I'd be very surprised if these bikes would have a speed limiter. On very long straight or slightly downward sloping highway stretches I've seen figures slightly above 180 kmph (i believe 183 or 186 was the tallest number) on both a stock X and an F also - pretty much reaching the rev limiter on stock gearing. Therefore I rather believe the bike in stock form limited by the rev limit in 6th, otherwise horsepower limited on longer gearing.
Keep in mind, that the figures are speedo indicated, I live @ almost sea level and ride EU spec bikes which might be slightly different (e.g. the velocity stack is different for the stock eu bike from the US and AU version).
 

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@Oyabun see my post at the previous site, I tested it several times with GPS (the speedo shower 187) on a straight piece of highway (interestingly, i can get to the rev limiter even slightly uphill, but is probably the stacks, filter and slipon responsibility) I am curious to see what @MraRacer#934 finds out, because this is getting suspicious ...
 

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There is no speed limiter on these bikes aside from the limitations set by physics. Taller gearing will not result in increased top speed. In fact, taller gearing at a certain point will reduce top speed. Some engine mods should gain a few mph. @tothezenith has done some of that. Perhaps he will confirm his rwe.

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With any increase of teeth in the drive sprocket or reduction of teeth in the rear sprocket, 6th gear becomes "overdrive". If that makes cruising in 6th at 75 mph more comfortable, go for it.
 

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There definitely is a speed limiter at 188kmh at stock bike. Physics or real limiter, I wouldn't know, but it definitely cuts off speed at 188kmh and keeps bouncing if you keep full throttle on.
 

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There definitely is a speed limiter at 188kmh at stock bike. Physics or real limiter, I wouldn't know, but it definitely cuts off speed at 188kmh and keeps bouncing if you keep full throttle on.
Sounds like you're bouncing off the rev limiter which is not a speed limiter per se, though it will limit the top speed in each gear. The rev limiter is designed to protect the engine mechanically.

A true speed limiter will cut in at some speed even though the engine clearly has more -- power and revs -- to give but the engineers limit top speed due to, say, tire ratings, brake capabilities or even for legal reasons.

The CBR definitely has a rev limiter but I don't think it has a speed limiter.
 

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Sounds like you're bouncing off the rev limiter which is not a speed limiter per se, though it will limit the top speed in each gear. The rev limiter is designed to protect the engine mechanically.

A true speed limiter will cut in at some speed even though the engine clearly has more -- power and revs -- to give but the engineers limit top speed due to, say, tire ratings, brake capabilities or even for legal reasons.

The CBR definitely has a rev limiter but I don't think it has a speed limiter.
Blackfin is correct. This is exactly the situation with the bike in it's stock form. Want more speed? You can do mods that will earn you a small increase, but at the cost of those, you're better off with a different bike.

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I got up to 182kph/113mph today. Feel like theres abit more to go but i had to slow down
On October 31st (my last ride of the season) I got it up to 179kph/111mph. I would have been able to go a little faster but a car merged into my lane on the autobahn. My gearing is stock and it's fantastic

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Just got the bike on the dyno and confirmed the stock ECU has electronic speed limiter built in at 105 miles per hour, however my dash indicated speed was 110 miles per hour.

Now we are trying to figure out how to trick the ECU so that we can get past this, because this is hurting me on the racetrack very badly.
 

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Interesting.
I assume you've tried more than one gearing (e.g. way longer gearing and using 5th gear) to confirm this. Was it fuel, or ignition limited? I also guess that you have disabled the factory rpm limit on the PCV or used rev xtend to make absolutely sure it is not an early soft rpm limit. Right?

You probably over this by now, but how I would approach this is I'd start by checking if it is gear dependent or not. If yes, avoiding that the ecu can detect if the bike is in top gear. I guess your bike is non-abs, then speed sensing can be only done from the gearbox, then use a speedo healer and trick the ecu to think it runs slower than actual - this way you have to cope with dashboard indication on the track and adjust your routine if you rely on speed in certain sections.
If it is fueling or ignition limitation, those could be potentially overcome by a piggyback tuner. Not sure if it'd work, but using gear based maps with revxtend on the PCV might get you somewhere. On my PCX, both my DIKTS Japan and Thai race piggybacks can circumvent the stock ecu limits.

The weather here is about 6 deg during the day, so not the ideal conditions to retest, but I'm pretty sire I've seen more than equivalent of 110mph (which is roughly 177 kmph) even if not much on the 2016 F when I was pushing it. Again usual caviats plug here; ideal conditions, German Autobahn, long stretches and potentially even a slight sloping, but still. So might worth a check if the ECUs are identical on all markets.

Keep us posted.
 

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Interesting.
I assume you've tried more than one gearing (e.g. way longer gearing and using 5th gear) to confirm this. Was it fuel, or ignition limited? I also guess that you have disabled the factory rpm limit on the PCV or used rev xtend to make absolutely sure it is not an early soft rpm limit. Right?

You probably over this by now, but how I would approach this is I'd start by checking if it is gear dependent or not. If yes, avoiding that the ecu can detect if the bike is in top gear. I guess your bike is non-abs, then speed sensing can be only done from the gearbox, then use a speedo healer and trick the ecu to think it runs slower than actual - this way you have to cope with dashboard indication on the track and adjust your routine if you rely on speed in certain sections.
If it is fueling or ignition limitation, those could be potentially overcome by a piggyback tuner. Not sure if it'd work, but using gear based maps with revxtend on the PCV might get you somewhere. On my PCX, both my DIKTS Japan and Thai race piggybacks can circumvent the stock ecu limits.

The weather here is about 6 deg during the day, so not the ideal conditions to retest, but I'm pretty sire I've seen more than equivalent of 110mph (which is roughly 177 kmph) even if not much on the 2016 F when I was pushing it. Again usual caviats plug here; ideal conditions, German Autobahn, long stretches and potentially even a slight sloping, but still. So might worth a check if the ECUs are identical on all markets.

Keep us posted.
What we found is that the rev extend will not work in 6th gear and 8800rpm in 6 gear is the equivalent to 9800 rpm in 5th gear regardless of the gearing. we were able to get the bike to get to about 114 miles an hour in 5th gear using a 16/42 combination which is the most we could do without changing the chain. Even when we disconnected the vs sensor the bike would still act the same in 6th gear. So now we are waiting for woolich racing to come out with flash tune capabilities for the ECU.
 

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What we found is that the rev extend will not work in 6th gear and 8800rpm in 6 gear is the equivalent to 9800 rpm in 5th gear regardless of the gearing. we were able to get the bike to get to about 114 miles an hour in 5th gear using a 16/42 combination which is the most we could do without changing the chain. Even when we disconnected the vs sensor the bike would still act the same in 6th gear. So now we are waiting for woolich racing to come out with flash tune capabilities for the ECU.
Have you contacted Dynojet about the issue that revxtend is not functional in 6th? I would check with them first.
I definitely can be wrong, but I can't remember to see a factory gear position sensor (apart from the neutral switch of course) in the gearbox.
Which then leaves the clue how on earth the ecu would now the difference between 6th and 5th gear.?
Was it a hard fuel based rpm limit, or a soft ignition retard one? (I'm guessing you had a wideband sensor hooked for the dyno session) to differentiate.
 

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How does the limiter function? Is it ignition or fuel regulated. How did you determine the ECU has a limiter function? Are we speculating or did we locate this within the circuitry? This is very puzzling to me. I'm finding this a bit difficult to believe.

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What we found is that the rev extend will not work in 6th gear and 8800rpm in 6 gear is the equivalent to 9800 rpm in 5th gear regardless of the gearing. we were able to get the bike to get to about 114 miles an hour in 5th gear using a 16/42 combination which is the most we could do without changing the chain. Even when we disconnected the vs sensor the bike would still act the same in 6th gear. So now we are waiting for woolich racing to come out with flash tune capabilities for the ECU.
Have you contacted Dynojet about the issue that revxtend is not functional in 6th? I would check with them first.
I definitely can be wrong, but I can't remember to see a factory gear position sensor (apart from the neutral switch of course) in the gearbox.
Which then leaves the clue how on earth the ecu would now the difference between 6th and 5th gear.?
Was it a hard fuel based rpm limit, or a soft ignition retard one? (I'm guessing you had a wideband sensor hooked for the dyno session) to differentiate.
Yes I spoke at length with Dyno jet about the issue and they claim that it is not a function of the Power Commander that it is a function of the ECU where is most Hondas have limiting programs built in for 1st and 6th Gear. Basically without flashing the ECU 6th Gear will always cut out at 8800.
 

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That's quite interesting about the 6th gear limiter. With stock gearing, 8800rpm would equate to about 111mph (177kph) as per gearing commander. Considering even Honda itself states its top speed of 115mph(185kph) at rev limit of 9100rpm and many on this forum have attested to exceed your mentioned limitation, and to at least match the stated top speed.
I personally have recorded numerous speed runs in excess of 180 with a top of 187kph both with stock and altered gear ratios, which was definitely into the 9s for rpm. It has aSpeedo Healer installed gps calibrated to <1% difference, and has more to give with the significant performance work and the PC-V rev Xtend to 9600rpm. So with the higher rpm cutoff, it has a theoretical top speed of 121mph(195kph) with stock gearing or 131mph(210kph) with my 38T sprocket. I've yet to encounter an opportunity on "private" roads to stretch its legs to the fullest though.
Note that I went through three different codes with DynoJet for the Xtend, first 10K then 9800 and finally just the base 500 increase to 9600. The other codes would stop a little shy of the the stock 9100, somewhere between 8700-9000.
@Blackfin has made a very valid point about real world conditions (not dyno'd) and the ability of the bike to overcome aero drag, not just the bike but the rider too; it's very noticeable over 100mph(160kph) that acceleration diminishes quite a lot. I doubt many of us are doing the speed runs in full race leathers tucked in like a chick to a hen. I feel that is my restriction too, I don't own race leathers and therefore am my own limitation to attaining it's full top speed, the bike just takes too long to progress through those upper speeds. Maybe when I take it into the shop next for its next service I'll have to do what MraRacer#934 did and ask them to spin it up on the dyno to see what my bikes stationary top speed is with all it's good bits on.
 

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That's quite interesting about the 6th gear limiter. With stock gearing, 8800rpm would equate to about 111mph (177kph) as per gearing commander. Considering even Honda itself states its top speed of 115mph(185kph) at rev limit of 9100rpm and many on this forum have attested to exceed your mentioned limitation, and to at least match the stated top speed.
I personally have recorded numerous speed runs in excess of 180 with a top of 187kph both with stock and altered gear ratios, which was definitely into the 9s for rpm. It has aSpeedo Healer installed gps calibrated to <1% difference, and has more to give with the significant performance work and the PC-V rev Xtend to 9600rpm. So with the higher rpm cutoff, it has a theoretical top speed of 121mph(195kph) with stock gearing or 131mph(210kph) with my 38T sprocket. I've yet to encounter an opportunity on "private" roads to stretch its legs to the fullest though.
Note that I went through three different codes with DynoJet for the Xtend, first 10K then 9800 and finally just the base 500 increase to 9600. The other codes would stop a little shy of the the stock 9100, somewhere between 8700-9000.
@Blackfin has made a very valid point about real world conditions (not dyno'd) and the ability of the bike to overcome aero drag, not just the bike but the rider too; it's very noticeable over 100mph(160kph) that acceleration diminishes quite a lot. I doubt many of us are doing the speed runs in full race leathers tucked in like a chick to a hen. I feel that is my restriction too, I don't own race leathers and therefore am my own limitation to attaining it's full top speed, the bike just takes too long to progress through those upper speeds. Maybe when I take it into the shop next for its next service I'll have to do what MraRacer#934 did and ask them to spin it up on the dyno to see what my bikes stationary top speed is with all it's good bits on.

So what I'm reading is that you've never tested the rev extend in 6th gear?
 

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So what I'm reading is that you've never tested the rev extend in 6th gear?
Well not to it's fullest, but have taken in 6th to at or slightly above factory limit of 9100 as mentioned in my post.

I have strong doubts of any form of speed limiter or 6th gear rev limit. There's just no logical reason for it to be a mere 300 from the normal limiter. And your mentioned corresponding 105mph speed is also an obscure number and mismatched to what stock revs would be at that speed. I'm more inclined to think something is off with your results, sorry mate.
I'm not going to totally rule a difference out, as a few of us have found regional differences with the engine; like the restriction in the velocity stacks the Euro guys have found.
 

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Well not to it's fullest, but have taken in 6th to at or slightly above factory limit of 9100 as mentioned in my post.

I have strong doubts of any form of speed limiter or 6th gear rev limit. There's just no logical reason for it to be a mere 300 from the normal limiter. And your mentioned corresponding 105mph speed is also an obscure number and mismatched to what stock revs would be at that speed. I'm more inclined to think something is off with your results, sorry mate.
I'm not going to totally rule a difference out, as a few of us have found regional differences with the engine; like the restriction in the velocity stacks the Euro guys have found.
I 100% agree with @tothezenith on all points. Something isn't right with your results.

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Anyone want to ask Honda directly about this? Honda Powersports 1-866-784-1870. They also have live chat, email, Twitter, and snail mail support. See contact options here http://powersports.honda.com/contact.aspx

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