Dirt bike idle speed question

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armedpolak
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Dirt bike idle speed question

Post by armedpolak »

manual for my WR250F says idle (when bike is warm I assume) is between 1900 and 2100 RPM. I have the power commander ECU and the corresponding unit I can plug into the bike to load and safe engine maps and monitor RPMs and temperatures and also pressure in the cylinder. I can't set it exactly at 2000 RPM like my OCD brain tells me to, so I have an option of it fluctuating (due to upgraded exhaust with less restricted air flow I assume) between 1900 and 2000, or 2000 and 2100 on average, though on the bit slower setting it hits 2000 half the time, 2050 about 10% of the time, and rest around 1950, occasionally dipping to 1900.

is this fine? am I totally overthinking this? or is it better to be at the low or high end of the idle RPM range?

btw I assume bike is fully warmed up with I can 1) have it idling for 5-10 minutes, 2) the cooling fan comes on and stays on, and 3) I can cook bacon on the titanium exhaust pipe :D

Also, how to best get a feel for the idle speed on my son's carbonated bike with no tools to measure it...

thanks!
AP
armedpolak
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Post by armedpolak »

Oh look I found an app to acoustically measure RPM :)

https://apps.apple.com/us/app/engine-rpm/id340401811
dammitgriff
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Post by dammitgriff »

Shut up and ride the damn thing, already.
Lmao!
armedpolak
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Post by armedpolak »

dammitgriff wrote: Sun Jan 03, 2021 3:01 pm Shut up and ride the damn thing, already.
Lmao!
I take my son and my dog for a walk in a park close by in the evenings. it has grass with small hills/bumps and gravel trails. it's totally empty after 9pm and yet the lights stay on till 11pm. so I walk the dog while sipping on scotch from my yeti cup LOL while he rides and the dog runs free.

my bike on the other hand needs one more modification: I need to install the stock sprocket; previous owner installed a +2 or +3 on in the rear. it's too torque'y for me :( however after reprogramming the ECU to stock map it certainly feels like the bike is much less homicidal toward me :lol: besides I haven't found a place to ride yet that is not a paid track, nor do I have a way to transport it yet. will get a hitch or a trailer soon. for now I took it for a spin around my neighborhood a few times to test the changes reprogramming the ECU did... so far so good...
armedpolak
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Post by armedpolak »

I also installed an ATV thumb throttle with a limiter for him. I could not find a twist one with a limiter so I put one for an ATV and reduced the engine to maybe 10-15% power. initially when he first rode it the throttle was too much for him and he crashed into bushed a few times. we had a talk about target fixation and throttle control, but I immediately got different parts and 3 days later he was practicing in the backyard for few days. now he rides in the park at night.

here's Nick 2nd time on a bike once I put thumb throttle with limiter (btw he now has full dirt bike gear and he wears it every time!):

armedpolak
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Post by armedpolak »

so I was able to confirm ECU reading on Yamaha and set my son’s bike idle rpm properly using the iPhone app :) mine is nearly at 2000 and my sons at 1500 according to the manuals!

Image


Image


Sent from my iPhone using Tapatalk
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photohause
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Post by photohause »

“You didn’t finish school, did you?
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tector
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Post by tector »

Everybody getting ready for Monday?
“Democracy is a pathetic belief in the collective wisdom of individual ignorance.”
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Tenzing_Norgay
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Post by Tenzing_Norgay »

tector wrote: Sat Jan 16, 2021 5:06 pm Everybody getting ready for Monday?
They started warming up today... :roll:

https://wsvn.com/news/local/miami-dade/ ... f-mlk-day/
- I can explain it to you, but I can't understand it for you... -
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tector
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Post by tector »

Tenzing_Norgay wrote: Sat Jan 16, 2021 11:49 pm
tector wrote: Sat Jan 16, 2021 5:06 pm Everybody getting ready for Monday?
They started warming up today... :roll:

https://wsvn.com/news/local/miami-dade/ ... f-mlk-day/
Yes, I already read--THIS year there will be STRICT enforcement!

:lol: :lol: :lol:
“Democracy is a pathetic belief in the collective wisdom of individual ignorance.”
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