patootoot!

Hello all! I'm new here and I hope I can get some help from the VTR experts.

I ride a 2001 Honda Vtr Firestorm from japan, and maybe some of you know that the japan version has a speedlimit, My bike taps out at 190-200kph.. as in it will not go any faster than that.

I asked a couple of people and they said that the best way is to change the whole gauge to a U.S. version and that will fix the problem. I found a 2nd hand gauge and i'm afraid to buy cause I'm not sure if its a "plug and play" type of thing. Im paranoid that something might go wrong if I change the gauge or or do some modifications.

I need help on this guys, you can just imagine a VTR in chains, so much power but very limited road.

Thank you all! more power!

Fozzy Bear

It's possible the speed limiter could be hard wired into the ECU

slabm7

Agreed, I can't see a govenor being tied into the gauges, more likely the ECU. What does the bike do when you hit 200kph. Does it just lose power?

Tweety

I highly doubt the gauges holds the key to this... The ECU is a much more likely culprit... Could possibly be both, but swapping the gauges alone will not fix the problem... The reason is that there is no signal back to the ECU or ignition from the gauges that can affect the bikes running... Not unless the jap spec wiringharness is completely different... And since that would most definetly be against Honda's normal policy to make things easy too produce, I highly doubt it... A jap spec ECU using all the same wiring and gagues, but with altered ignition maps are infinetly more likely...

Well... The only help I can offer on the paranoia is to tell you that unless take some chances you might as well stop right now... Nobody will be able to assure you 100% that everything is problem free... We don't have a jap spec bike to try stuff on, and the only way of knowing is to try...

What I can tell you though with 100% certainity, is that you cannot possibly screw the bike up to a point where it's not a fixable problem... Well, unless you use a five pound hammer on it...

patootoot!

Thanks guys for the reply, It really helps.. I will have that ECU checked by a mechanic/electrician.

@Slabm7 - When the bike hits 200kph, it feels like it has a choke or a hiccup then bogs down to 195kph then goes 200kph again. just a cycle

slabm7

There must be something tied into the ECU that cuts the fuel or ignition at 200kph. Some smarter people will chime in here shortly but you may have to get a ECU from North America or the UK to unleash that thing.

ripvanwinkle

Don't quote me on this as being the gospel truth, but didn't I read somewhere that the home Japanese version bike has modified carbs that restricts the power. The only way around this is to replace the carbs as they can not be changed back to give full power.

If I've got this right (and it's a big if) may be someone else can remember this

Oops I nearly forgot, welcome aboard.

PJay

It might be simpler - some markets have very simple restrictor plates in the VTR carbs, reducing diameter to about 30mm. Pull the carbs and check, as the plates are easily removed.

Tweety

Well... Sorry guys, but restrictor plates and other carbs might limit performance...

But it's not going to make a bike cycle at 195-200-195... That's the ECU cutting the spark or otherwise modifying the ignition curves... That's an electronic limiter, not a mechanical... And the only likely place for it to bee is in the ECU, since there are as I stated above no signals back to the ECU/CDI form the gauges...

8541Hawk

I would really have to agree here. About the only place to limit the bike like that would be the ECU. Then again I have been wrong before......

PJay

Accepted.

If you Google "Japanese market speed limiter", one of the links you'll find has a diagram for disconnecting the same thing on an RC51 for US use.

Or you could replace the ECU with one from a wreck.

patootoot!

Wow great info, You guys have been a big help. I'm guessing I should start with the ECU as the first step.

@ripvanwinkle- Thanks for the welcome,

tristanNZ

Unbolt the ferring, and remove the cluster. Unscrew the back cover of the cluster. On the speedo side, you will see the following wires. Green Black. Black Brown. Red Green and Pink Green. Take note of that pink green wire. (Do not touch it. That is the speed sensor wire for the speedo from the gearbox, if you unscrew that, your speedo WON'T WORK) Looking at the back of the speedo (cluster), you will see a second pink green wire that is just off the the left that is screwed at the bottom on a line of 4 screwed in wires. Unscrew that second pink and green wire, tape it up. And there you have it. Speed limiter removed. So in short, look for the pink and green wire that is as close to the center of the cluster as possible, and unscrew and tape up. It should take around 10 minutes. EASY AS! The longest part is removing the ferring and 3 cluster bolts. - You don;t even need to unplug the loom. If you pull the cluster right apart there is a little chip in there that sends the cut signal to the ecu. Technically now the ECU doesn;t know how fast you are going. I had a Firestorm that was limited to 185k's, after a 10 minute job, and a 20 minute ride you're set to go.. . . PLEASE REMEMBER ... RESPECT THE POWER AND SPEED. ONE WRONG BLINK AND IT'LL BE CURTAINS. BE SAFE.

NHSH

Just posted something about this earlier, but deleted by mistake, yes you are correct, a friend of mine from Dunedin that used to import used bikes in containers from Japan, did mention that to me awhile back about the speed limiters.

It's not something that people need to deal with in the states or Europe as there are close to non imported used bikes from Japan in these regions except Aussie & NZ, still nice write up for the chance that someone do need help on this.

Cheers mate

RedStormJ