ECU upgrade headaches.. possible solution (for the engine modding members)

[m in sc]

So, aside from going from a standalone (which is still 'iffy' in my opinion on this bike) I decided i'd go ahead and do some digging and ask some questions of those that actually flash ecus. Heres what i found out:

so, the trail one can not be re-flashed due to a map sensor issue that ONLY the super cubs and trails have. says its unique and i can see that. also, it CAN be bypassed.
However, the 2022 grom and monkey ecus have the same interface as the trails do. those CAN be remapped. the timing curve on the trail is what's really holding back any potential power. the new gen ecus all run in open loop fueling, so, they WILL indeed learn fueling through the whole rpm and throttle range. (probably why mine hasnt blown up yet)

the cyl and head are the same across all models. the throttle body is the same size. New groms can do 72 mph legit with a pipe and a reflash and not be stressed. so, what i did was i have ordered a 2022 grom ecm. it was cheap. I'm going to plug it in to the trail when it arrives, and see if there are any issues. the only one i am sort of expecting is the map sensor, and if that's truly by-passable (which they do with standalone ecms.. ) I should be ok. If everything is good,, i can then send that out for a reflash and should be right as rain, and be in under 250 bucks total. this will open up the possibility for serious big bore kits, etc.

when i get this tried out will report, its supposedly on way now.

 

[Clancy oto]

Heck yes!

Keep us posted mate!


Sent from my iPhone using Tapatalk

 

[Cardinal Direction]

Curious as to how this will play out, I don’t know about any of this stuff but this sure seems interesting

 

[m in sc]

looks like the ecm will ship on the 10th or so.

 

[Shoot870p]

Awesome!
thanks m.
walker

 

[SLO]

So, aside from going from a standalone (which is still 'iffy' in my opinion on this bike) I decided i'd go ahead and do some digging and ask some questions of those that actually flash ecus. Heres what i found out:

so, the trail one can not be re-flashed due to a map sensor issue that ONLY the super cubs and trails have. says its unique and i can see that. also, it CAN be bypassed.
However, the 2022 grom and monkey ecus have the same interface as the trails do. those CAN be remapped. the timing curve on the trail is what's really holding back any potential power. the new gen ecus all run in open loop fueling, so, they WILL indeed learn fueling through the whole rpm and throttle range. (probably why mine hasnt blown up yet)

the cyl and head are the same across all models. the throttle body is the same size. New groms can do 72 mph legit with a pipe and a reflash and not be stressed. so, what i did was i have ordered a 2022 grom ecm. it was cheap. I'm going to plug it in to the trail when it arrives, and see if there are any issues. the only one i am sort of expecting is the map sensor, and if that's truly by-passable (which they do with standalone ecms.. ) I should be ok. If everything is good,, i can then send that out for a reflash and should be right as rain, and be in under 250 bucks total. this will open up the possibility for serious big bore kits, etc.

when i get this tried out will report, its supposedly on way now.

I would be happy with the set up you got. WTF? I think you wanna race the SLO RANGER. Maybe the road traveled will favor the the SLO one.

 

[m in sc]

I have no idea what that even means. I just want to be able to maintain 60 w out stressing it too bad, i don't go off road with mine not what i got it for, its a commuter/parts hauler. Im typically not a 'leave it 100% stock' guy, if you couldnt tell.

 

[rundmm]

I also bought mine to be a commuter. It can run at 50 and sometimes better if the wind is on my back. I would love to be able to hold 55-60 and not get run over by traffic. I just want to see if I understand what you are saying, if you drop in a re-flashed ecu and get a yoshimura or compatible pipe, you should be able to get to 60 without issue? I hope you can. That would be a game changer for not to hefty a price. Also, is that with or without a big bore kit?

 

[m in sc]

I'm not sure, i'll have to try it and see. I have a 143 & cam on mine though. which just lets me get up top speed way quicker, and has way more torque for climbing hills. I don't need to downshift nearly as much as stock. (now). I can currently hit 55 easily on flat ground, and hold it, and im 210 lbs. But it just hits a wall. no where near the rev limiter in 4th. (can hit 50 at rev limiter in 3rd now). Im just waiting for the ecm to ship. Been delayed 2x.

 

[rundmm]

Which 143 kit do you have and do you have to add the cam to it? Buddy of mine is very good at working on bikes and wants to help me upgrade. Originally, I did not really want to put a kit on it because I really wanted the mpg and the reliability of the Honda. Don't really know if a kit would hurt the mpg or not but mpg was the reason I bought the bike in the first place. Now that I have been on the road at 50 mph and had cars zip past me, seems like a little more umph would be great. Hell, holding 55 mph would be great. I am look forward to seeing what you find out in the future on this mod. If you could get it to 60 reliably, would be a game changer.

 

[m in sc]

ultimately wound up with the yuminashi kit. it has proven very good, after the takegawa one let me down. thread here:

143 Takegawa cyl install.

this is a few pics from installing the takegawa 143cc cylinder. I also updated the cam chain tensioner with a koso unit, and installed a pcx150 honda injector at same time. wasn't bad. about 4 hours. prior to this, already installed a TB cam and an efie fuel management device, and de-catted...

hondatrail125.com

 

[SLO]

Ok. I don't know where this is coming from (my head) I put a 13 tooth front sprocket on bike and never had a ABS light issue. The speedometer would be off by about 7 percent. I do not mind being corrected, I am just guessing. However I put shinko 244 3/0 tires on back,put stock back on front. 23.5 diameter vs 22.5 diameter tire on rear. That should give me a gain of about 8 percent, offsetting adjustment needed for speedometer correction. With a speed about 1 percent greater than the speedometer indicates.I do not mind being corrected as I am guessing. SLO wants others to do math for him. Ok what was I supposed to be doing before I walked past the RED ROCKET and got thinking.

 

[m in sc]

just check it with gps. I mean it makes sense. the taller tire also negates any final gearing 'advantage' with the 13t ft sprocket. so it pans out for the most part.

 

[AZ7000']

So my stock 14 and the 244 3.0’s should be a double dog??? I just twist it at 7000’ in the mountains. 12% hill with me and the 9yo coming home from soccer or running club and needed to drop to 1st gear, can maintain power with just me riding it hard right at about 18 mph. A right turn at the start so hard to get a run at it.
I’ve had the trail 90 at sea level and loved the power.
Some day…. Some day

 

[SLO]

just check it with gps. I mean it makes sense. the taller tire also negates any final gearing 'advantage' with the 13t ft sprocket. so it pans out for the most part.

Got it. Thanks. I could not find a OEM size suitable tire, is why I went with the shinko 244 3/0. After the exhaust upgrade, air filter upgrade it runs great. Still lacking on very steep hills at high altitude. I might ride 140 miles without a car behind me,or the road is so curvy that I am not constantly looking back , or pulling over. Is a fuel controller necessary if I change the cam only ,without changing displacement? Read post on your swap. Excellent!

 

[SLO]

So my stock 14 and the 244 3.0’s should be a double dog??? I just twist it at 7000’ in the mountains. 12% hill with me and the 9yo coming home from soccer or running club and needed to drop to 1st gear, can maintain power with just me riding it hard right at about 18 mph. A right turn at the start so hard to get a run at it.
I’ve had the trail 90 at sea level and loved the power.
Some day…. Some day

I put the original front tire back on, cause it was a power grabber. I paid $ 11:50 for the 13 tooth front sprocket delivered. Easy , and only took about 30 minutes tops.Noticeable effect!

 

[SLO]

just check it with gps. I mean it makes sense. the taller tire also negates any final gearing 'advantage' with the 13t ft sprocket. so it pans out for the most part.t the GPS

just check it with gps. I mean it makes sense. the taller tire also negates any final gearing 'advantage' with the 13t ft sprocket. so it pans out for the most part.

Does the GPS indicate nautical miles per hour? That would indicate slower than actual ground speed.

 

[dmonkey]

Edit: It seems GPS mapping software often use a 2D geographic coordinate system for navigation, but GPS speed can be 3D if the device and software make use of the GPS data available to them.

 

[m in sc]

i would get something to control the fuel a bit, especially with air filter and exhaust changes. the intake in particular makes the biggest single difference.

 

[AZ7000']

I put the original front tire back on, cause it was a power grabber. I paid $ 11:50 for the 13 tooth front sprocket delivered. Easy , and only took about 30 minutes tops.Noticeable effect!

I have a 13t, just haven’t taken the time. And was worried about the abs light which appears to be a non issue???