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Discussion Starter · #1 ·
I have a cbr250r and it was stolen before I received it, so the ignition had damage on it. I bypassed the zener diode on the ignition by installing a power inverter and running a nine volt power supply to the wire on the ignition. And it ran like this for around two months roughly. I took it to the river and it has a pretty good strip to run the bike down. I was seeing where the top was with the new carburetor I installed bypassing the pump and injector style it had originally and running a gravity fed one instead as well as I had the rev limiter removed and new back sprocket and front sprocket. I hit around 135 roughly on the first run down then 142 second run turning around for the last time i got to a funny angle with the bike and just let it set down at walking speed i literally set it on the ground. I reset the ecu on it and tried everything from compression, carb, spark plug, ignition coils, igniter, checked the inverter, power supply, and everything else can't figure it out, but i start it fires up then dies 3 seconds in can rev it or idle for those 3 seconds but after that i have to switch off the bike with the kill switch and it will start again and then die 3 seconds in any help would be greatly appreciated. I am mechanically inclined but no master mechanic so feel free to lamen termed any of it you can lol thank you.
 

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Honda: INNOVA125i(2010); CBR250R(2013)
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Hi
Why do you mention the 9 volt battery thing, do you think it ran out? Because if so then replace it.
If I understood correctly, everything worked as it should, until THE "failure" appeared? To find faults, you have to work in a cold mind and calculated way. Go by the book, and start with what's easy, check that the fuel isn't contaminated and that it flows freely through the system pipes, check the electrical system... and you can briefly describe your problem to John Talley from Parzilla (every Friday), he's happy to help, he helped me too.
 
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very complicated way to get 9v on pink wire. Why not just take 9v from after diode?

bypassed the zener diode on the ignition by installing a power inverter and running a nine volt power supply to the wire on the ignition.
Measure voltage on pink wire where it goes into ECM connector.
 

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I have a cbr250r and it was stolen before I received it, so the ignition had damage on it. I bypassed the zener diode on the ignition by installing a power inverter and running a nine volt power supply to the wire on the ignition. And it ran like this for around two months roughly. I took it to the river and it has a pretty good strip to run the bike down. I was seeing where the top was with the new carburetor I installed bypassing the pump and injector style it had originally and running a gravity fed one instead as well as I had the rev limiter removed and new back sprocket and front sprocket. I hit around 135 roughly on the first run down then 142 second run turning around for the last time i got to a funny angle with the bike and just let it set down at walking speed i literally set it on the ground. I reset the ecu on it and tried everything from compression, carb, spark plug, ignition coils, igniter, checked the inverter, power supply, and everything else can't figure it out, but i start it fires up then dies 3 seconds in can rev it or idle for those 3 seconds but after that i have to switch off the bike with the kill switch and it will start again and then die 3 seconds in any help would be greatly appreciated. I am mechanically inclined but no master mechanic so feel free to lamen termed any of it you can lol thank you.
Wait - what?

Things are not making sense...
 

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Discussion Starter · #7 ·
Was the inverter I had on there was faulting out and not sending the nine volts and I use the inverter because the diode went bad well I am using a new diode as of tomorrow they just arrived today I order
a bunch online cheap. And no I mean mph. And I don't know exactly how my buddy does it to be honest on the rev limiter but I'll ask him tomorrow. I have done allot of tuning on this thing from shaving certain parts of the frame down or cutting excess frame off to port matching the intake and exhaust and polishing as well as my dad milled the head and we have put new valves, changed sprocket size, and my dad an buddy did some dynoiing on it as well
 

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cutting excess frame off to port matching the intake and exhaust and polishing as well as my dad milled the head and we have put new valves, changed sprocket size,
All the changes don't explain a speed of 142MPH(228 km/h). To what ratio your sprocket were changed, I'm guessing your speedometer is now faking upwards...but even that can't explain the speed you claim. Some serious aerodynamic design is needed here. Please upload here some pictures and we'll see what CBR left after all the cuts and changes.
the last time i got to a funny angle with the bike and just let it set down at walking speed i literally set it on the ground.
And maybe your problem is with the tilt meter (BANK ANGLE SENSOR 35160-KPP-T01) that is in the front of the front cowl...but maybe you took that out too?

Please upload for us a pictures from your project. Thanks
 
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All the changes don't explain a speed of 142MPH(228 km/h). To what ratio your sprocket were changed, I'm guessing your speedometer is now faking upwards...but even that can't explain the speed you claim. Some serious aerodynamic design is needed here. Please upload here some pictures and we'll see what CBR left after all the cuts and changes.


And maybe your problem is with the tilt meter (BANK ANGLE SENSOR 35160-KPP-T01) that is in the front of the front cowl...but maybe you took that out too?

Please upload for us a pictures from your project. Thanks
Pretty sure a factory Moto3 race bike (250cc single) won't go that fast!
 

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Discussion Starter · #11 ·
What's trolling me give me a little bit I'll send pictures of bike and better explain what's been done to the bike after I talk to the one who helped me put it together and no I already said It was the power inverter on the bike had gone bad replaced it and now it's running great again. And no bank sensor is definitely not removed much needed with me trying this whole bike drifting and what not lol.
 

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What's trolling me give me a little bit I'll send pictures of bike and better explain what's been done to the bike after I talk to the one who helped me put it together and no I already said It was the power inverter on the bike had gone bad replaced it and now it's running great again. And no bank sensor is definitely not removed much needed with me trying this whole bike drifting and what not lol.
No idea...
 

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Actually 155 mph is their top on moto gp3's
With DOUBLE power and HALF weight of CBR250 in much, much more aero package (150mm narrower). I'd like to know what mods you have done to QUADRUPLE power-to-weight ratio of factory CBR250 and reduced width by 6". Most have only gotten +10% with every costly bolt-on mod possible.

With factory sprockets, you're hitting 90mph max in 6th gear just @ redline...


Switch speedo to kph and we have... AHAH!!!
 

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We actually had NSF250R race with our club couple years ago. Here's start of round-7 @ Buttonwillow:


By 2nd lap, he had moved up to 2nd place just behind TZ250 with double the power (4x more than CBR250 or 8x power-weight ratio):


Overall, NSF250R was putting in lap-times as fast as 600 Supersport bikes with 3x the power. About 15-sec/lap faster than street 250 4-strokes (CBR250 and Ninja 250). That's THREE football pitches ahead PER LAP!!! Or about 1/2-km ahead PER LAP!!! I'd like to know how to convert CBR250 to be this fast!!!

Here's one for sale if you can't get your bike running: Featured Listing: 2018 Honda NSF250R Moto 3 Race Bike For Sale - Rare SportBikes For Sale
 
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