crf450r 45kw race bike build

j bjork said:

You only get 4100 unloaded? That sounds strange, I would expect something like 5500

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I did not test it. This rpm is the spec for the qs180 on their spec sheet

Back on this project after a dislocated shoulder and house renovation!
I tried it on a real track around mid august and the bike was very bad. On a track it felt slower than a 125. I lost traction on the face of a jump and hurt my shoulder again. Yesterday I finally tried the bike again this thime with the dual fan and the new gearing. Again even with new gearing the this is deceiving. The power curve is not good. The initial throttle twist is powerfull then it becomes slow. Top speed is 53 km/h.
Here are screenshot of the log. 7 minutes of riding this time the outside temp was 19 degree celsius.

Hmm, that doesn't seem right; the qs180 should provide "good" of power/thrust at ~30kw - certainly more than a "125cc" feeling I would think. Can you log a few short acceleration runs (from stopped to near full speed)? We can then see the what the power curve looks like and it might highlight something.

Yeah a zoomed in log that just shows dead stop to full speed as one full throttle pull would be more insightful. Particularly motor current, duty cycle, maybe battery voltage.

So today I tried to do some log as requested. Only 2 worked as it seems like vesctool would not keep connected to the controller.
Did a top speed with my phone gps wich is 85 km/h. This is too slow as a 250 top at around 120km/h.
I will try to explain better the piwer of the bike:
When everything is cold and the battery is full the bike as a lot of power to around 40 to 50 km/h. But this power last for 2 to 3 acceleration then it gets slower and slower. For trail riding this is not a problem but for motocross riding it is now good. Every acceleration out of a corner get slower.
Here is the voltage drop during a 10 sec acceleration:

Controler temp during 10 sec:


And look like the controller was not able to log the motor current on the first acceleration:


but it did on the second:


and the duty cycle frist :


second acceleration duty cycle:

I think that if you need real help you should probably post all your settings. Otherwise it will be an endless game of guessing and shooting arrows in the dark.

Dui ni shuo de dui said:

I think that if you need real help you should probably post all your settings. Otherwise it will be an endless game of guessing and shooting arrows in the dark.

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Well I am not looking for help since nobody almost nobody her use their bike for motocross racing so they do not encounter the limitations I get. I am just documenting the project and if someone want to build one will see what are the real performance of a diy electric dirt bike. For trail riding and playing around it is good but there is no way that this can compete with gas bike on racing environment.
The controller and the motor heat up way too fast. Also the settings were made by hackey and he told me to not change anything to not damage the controller.