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Discussion Starter #1 (Edited)
Hello everyone,,
Right now I have a Chimera Intake and Comp Werkes exhaust, and next week I'm ordering a PC V (unless someone knows of a better chip!). After that I'm going to play with gearing a little bit, and hopefully I will break 70, with an end goal of 75. I know I will probably need a little more work than this to get my speeds.
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What did you do to hit those numbers on flat ground?

Big bore kits are out of the question, I'll throw a Daytona 190 motor in before boring it.
 

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14t front, RS2 exhaust, Yosh ST1M cam, Dinger mid intake, and CJR flash got me in the low 70s.

Edit: Also bumped up the rev limiter to 10K (CJR flash).
 

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In my testing any piggy back ECU will set you back, either go stand alone ECU or re-flashed ECU.

I started out with PCV with WB02 and I kept getting hicups and other strange problems with fuel and timing once I switched over to a Aracer ECU the majority of my problems went away.

Save your money for the good hardware such as Kitaco clutch side cover, port and polish your stock head including port matching and valve lapping. Get a matched cam and duel valve springs. Open up your intake on your head to 26-27mm and do the same for the inlet tube that your throttle body is mounted on. Use a PC-150 F/I. Get the GFZ speed spacer and adjustable cam chain tensioner and Koso cam arm kit, 4th bearing support for the fly wheel.

Good Luck and ride it like you stole it
 

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Getting in the 70s without an aftermarket cam will be very difficult without a very steep hill... 😆
And I'd go with a reflash or aRacer if you have money to spare. A PC V on its own is pretty much useless, you'll want to add an autotune module and an AFR gauge, altogether it's getting expensive and won't work as well as an aRacer.
 

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To be 100% honest, 70 mph without tucking is a lofty goal. I have the Cameron Jones Racing stage 1.2 with the Dinger Built short intake, Hindle exhaust, DCR R2 cam, his ecu flash and a 14T sptocket. I weigh 170lbs without gear and I'm 6'1". I average about 65mph sitting upright, yes I hit 70 occasionally on really flat or slight downhill grades , especially after just lubing the chain. However an average of 65 is more likely. I can hit 75 anytime I want to with an extreme tuck, this is bouncing off of my 10,000rpm limiter though and not comfortable for long distance. I believe the addition of a DHM high compression piston would make for a more consistent 70mph.
 

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honest question, on stock gearing and stock motor. Wont a grom go 72 bouncing off the limiter?
 

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Yes, 73 actually. If you have the power to push it that fast. Most 125cc will benefit from a 14T sprocket, it will lower max speed to 69mph at stock redline but it is far easier to get there.
 

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What did you do to hit those numbers on flat ground?

Big bore kits are out of the question, I'll throw a Daytona 190 motor in before boring it.
First off, how much do you weigh? When I weighed 155 lbs, I was hitting speed much easier than 175 lbs. I also swear that pulling the mirrors off is good for 1-2 mph on the stock displacement motor.

For me - Kitaco high-comp. piston, TB cam, open throttle with a UNI filter, PV3 tune, and exhaust. Played with sprockets until I could hit 72-75 mph flat tucked. Probably could have done it before the piston. This was on a 140 rear tire with a 428 chain, so I was lugging plenty of extra weight on the motor.

I don't know why BBK would be out of the question. I installed a 181 NEO kit and it's the best thing I did to the bike. I find myself hitting 60-65 mph in 45-50 mph speed zones without effort or intent.
 

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i live down in Florida where everything is flat, with just an air box mod and an exhaust i was able to do 72/73 on my bike. Mind you i weigh 140lbs and it was on the interstate drafting all the cars.
 

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Weigh 150lbs before gear lol but then added a DCR R1 cam, finbro ecu with PCX 150 injector and the limiter raised to 12,500 (but I shift around 10500), kitaco clutch cover to remove the heaaavy oil spinner, evap system and charcoal canister delete (weight), mnnthbx intake, zoom straight exhaust (came with the bike so not the best). Who knows how negligible the drag reduction is but I also run no mirrors, the ruck shop racebars so I’m naturally a little less upright, and the TsT flush fender eliminator. Pulls hard with the cam and cruises at around 73 at the stock redline. Best I’ve pushed it is around 77.
 

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I have a stock bore with a TB cam, a reflahed ECU, and intake and exhaust and stock gearing. I can hold it at 60 when no wind and not tucking. If I tuck I can hit and hold 65. I have drafted a car and hit 73 but I dont usually ride like that.
I do have a 14t and 16t front sprocket so I can change it at any time but its only like a 2-3 mph difference. Just depends on whats going on that week. You can change out the front sprocket and adjust the chain in like 15 minutes.
 
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