Power in Flux
Likes Likes:  4
Page 1 of 2 12 LastLast
Results 1 to 10 of 14

Thread: Soyachipsí Electric FZR250

              
   
   
  1. #1
    Senior Member soyachips's Avatar
    Join Date
    Aug 2010
    Location
    Sydney, Australia
    Posts
    103
    Post Thanks / Like

    Soyachipsí Electric FZR250

    Chassis: 1989 Yamaha FZR250 2KR
    Motor: QS 273 6000W V3 hub motor
    Speed Controller: Kelly KLS7250H
    Batteries: TBD

    Top Speed: TBD
    Range: TBD

    So itís been a while but Iím at the beginning stages of my next project. Just bought the donor bike and waiting for it to be transported interstate. Also waiting for the motor to be sent down from China so in the next couple of weeks I should be able to get started. Wohoo!

  2. Likes Stevo liked this post
  3. #2
    Senior Member soyachips's Avatar
    Join Date
    Aug 2010
    Location
    Sydney, Australia
    Posts
    103
    Post Thanks / Like
    I originally thought about doing an electric cafe racer motorbike as thereís something appealing about the way they strip everything back to just the essentials and expose the way it all works but I struggled with how to make the batteries look good. In general, EV batteries donít look that good so I then changed tack and started looking a bikes with fairings so I could hide them! Iím also keen to use a hub motor to simplify the conversion and leave plenty of space for everything else. The other thing I am trying to do is make this as easy as possible to get an engineerís certificate for the conversion. I spoke to a few engineers about the project and a common theme was donít touch the brake system otherwise youíll need to do brake testing which could add another $3,000

    I had read good things about hub motors from QS Motor and they have a pretty extensive range of options. The bad thing was the hole pattern for mounting the brake rotor seemed non-standard so I thought Iíd have to use the rotor that comes with the motor which is 220mm. So some more research to find bikes that use that size rotor on the rear and fairings to hide the batteries. The other thing was using a frame that has a cradle under the engine so when I take the the engine out itís still structurally ok. Most new bikes seem to use the engine as part of the structure so that ruled out a whole lot of newer bikes. This really narrowed down the options so I finally settled on a late 80ís Yamaha FZR250 as my donor bike and proceeded to buy a swingarm and rear brake bits from a wrecker to do some prototyping.

    Below are some photos of 3D printed custom axles to get everything fitting and the wheel centred and modifying the slots in the swingarm where the axle normally goes through into dropouts like on a push bike so I can get the motor in. On motorbikes the axle gets inserted through the swingarm into the wheel but on the QS hub motors the axle is fixed in the wheel.





    Last edited by soyachips; 3 Weeks Ago at 2227.

  4. #3
    Senior Member soyachips's Avatar
    Join Date
    Aug 2010
    Location
    Sydney, Australia
    Posts
    103
    Post Thanks / Like
    I also tested where the rear rotor would end up relative to the existing brake calliper and mounting bracket setup. In the prototype below everything looked like it was going to line up but then I realised the wheel was a bit off centre! So after fixing that, I will now have to use an adapter plate between the motor and the brake rotor to line everything up ... which means I wasnít limited to using a bike with the size of brake rotor that comes with the motor in the first place!






  5. #4
    Senior Member soyachips's Avatar
    Join Date
    Aug 2010
    Location
    Sydney, Australia
    Posts
    103
    Post Thanks / Like
    Sorry the images above are huge and having trouble working out how to resize them, any ideas? Weird but when they're bigger it's harder to see what's going on!

  6. #5
    Senior Member soyachips's Avatar
    Join Date
    Aug 2010
    Location
    Sydney, Australia
    Posts
    103
    Post Thanks / Like
    Because the axle is built into the motor and needs to be held firm while the motor spins, there will be a lot of torque where the axle passes through the swingarm. To make this stronger Iím going to use solid blocks of aluminium? inside the swingarm. The tolerances need to be quite tight as there are acceleration and regen torque forces that need to be counteracted.


  7. #6
    Senior Member soyachips's Avatar
    Join Date
    Aug 2010
    Location
    Sydney, Australia
    Posts
    103
    Post Thanks / Like
    Here are some pics of the custom axle and motor.






  8. #7
    Senior Member soyachips's Avatar
    Join Date
    Aug 2010
    Location
    Sydney, Australia
    Posts
    103
    Post Thanks / Like
    This is the donor bike I just bought. The previous owner put a lot of TLC into it so it looks like itís in really good condition. As mentioned I selected this bike because of the size of the rear rotor :lol: but apparently itís a really good bike and one of the better 250ís from that era.




  9. #8
    Senior Member Stevo's Avatar
    Join Date
    Nov 2014
    Location
    Behind the Redwood Curtain- REDWOOD ORIGINAL!!
    Posts
    755
    Post Thanks / Like

    My Social Networking

    Add Stevo on Google+
    What does the new rear wheel weigh in at compared to the original? I would consider rebuilding the shock with a stiffer spring and maybe a gold valve, but after search I found that the OEM rear shock is not rebuildable http://www.racetech.com/ProductSearc...FZR250/1986-88
    I'll be curious to see how well you can make this bike handle with the added battery weight also.
    Current rides: '96 Honda Ohlins VFR, '03 Cannondale C440R, '03 Cannondale Cannibal, '06 Yamaha 450 Wolverine 4x4
    Current builds: WORX.VOR.v3.2

  10. #9
    Senior Member soyachips's Avatar
    Join Date
    Aug 2010
    Location
    Sydney, Australia
    Posts
    103
    Post Thanks / Like
    Quote Originally Posted by Stevo View Post
    What does the new rear wheel weigh in at compared to the original?
    I'll be curious to see how well you can make this bike handle with the added battery weight also.
    The wheel is 20kg! No idea what a normal wheel weighs and I havenít got the donor bike yet but there will be quite a difference. Iím a bit concerned about that too. In deciding what kind of setup to go with I thought the simplicity of the hub motor and leaving plenty of space for everything else would make for a nice conversion and hopefully the handling will still be good. Will just have to wait and see but Iíll need an experienced rider whoís game enough to ride my bike to see if itís any good as Iíve only just started riding so I wonít have much to compare it to

  11. #10
    Senior Member Stevo's Avatar
    Join Date
    Nov 2014
    Location
    Behind the Redwood Curtain- REDWOOD ORIGINAL!!
    Posts
    755
    Post Thanks / Like

    My Social Networking

    Add Stevo on Google+
    Its a good chassis choice. Single front brake keeps the weight down and the steel frame makes it easier to weld/make mods. I hope you found a great deal on it.
    The unsprung mass of hub motor is what made me decide a different set up. But if suspension is set up right, it should work fine, giving lots of space for batteries.
    I would like to see an e-version 2 wheel drive set-up using hydraulic pumps ala Ohlins http://www.motorcycle-usa.com/2009/0...ns-2wd-review/, but 2 hub motors would work.
    Last edited by Stevo; 3 Weeks Ago at 0851.
    Current rides: '96 Honda Ohlins VFR, '03 Cannondale C440R, '03 Cannondale Cannibal, '06 Yamaha 450 Wolverine 4x4
    Current builds: WORX.VOR.v3.2

Page 1 of 2 12 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •