cbr250r streamliner sport style

[bschloop]

Here is a simulation for a brushless hub motor in a motorcycle. It should give a better representation of efficiency as it relates to speed.


The black line represents efficiency. Notice the bump and subsequent drop as the vehicle approaches top speed. This coincides with the steady state curve I showed earlier. It seems that efficiency is greatest just before top speed in this simulation. It also shows that efficiency is about 20% lower at half of the top speed, and over 40% lower at a quarter speed. All of this supports the need for a multi speed transmission. It also makes me think more that Brammo might not have made a mistake in their design. Maybe the reviewers simply didn't understand the proper use of the transmission as it relates to extending range aka increasing efficiency.

[bschloop]

It looks like I will need to do some further research on ev efficiency, but it still looks to me as if the multi speed could add a good bit of range if employed properly.

[sendler]

I guess it is just the top half of the rpm range that has a flat efficiency curve. The simulator at ebikes.ca is fun to play around with.
.
http://www.ebikes.ca/tools/simulator...2f5c3ee52d5008
.

[Grant-53]

One of the issues with PWM controls is the current draw at low rpm.

[bschloop]

Back to the project at hand. I finished shaping the plug, and have begun waxing it so that I can pull a mold.
This fairing will be the basis for the CBR. I'll be designing the rear section next.

[renault_megane_dci]

Nice !

[Grant-53]

Check the latest mods at Chapter 83 from Craig Vetter.

[bschloop]

Finished pulling the mold last night. It didn't want to release, and took some small bits of the plug with it.
Apparently I didn't get enough wax, or PVA, or something. The bits that came off the plug are all either primer, or Spackle, so I can remove them pretty easily.
I'll be extending the parting flange so that I can vacuum bag the final parts. All things considered, it's not that bat for my first full sized mold.

[travelingaaron]

Curious if there was any more progress here. Bought a CBR300 around the time of the last post and would love to see updates if there are any. Any chance you could tell me where you got the handle bars?

[HHOTDI]

yes...updates please! :{)