GoldenMotor.com Forum
General Category => Electric Motorcycle Conversion => Topic started by: Rickard M on February 20, 2018, 09:17:45 AM
-
Hello, my name is Rickard and I'm from Sweden.
I have just built a electric MX. I''m new to theis electrical world, still learning, I got great support from Robin at GM when I bought the parts. First it ran backwards, and I didn't manage to get the wires in correct order, so then I got 6 connection ways that would work, and it did... I have also managed to connect the controller to a laptop so I can adjust the parameters. But I don't really understand what they all do... So I'm hoping to get some further help now so it can be even more fun to drive :)
First a pictures of the bike, it is made to look as close to an original Yamaha YZ80 as possible.
(https://i.imgur.com/LPdgdnS.jpg)
Whit the gearing (11 tooth front and 54tooth rear) I have now it have a topspeed that is more than 60km/h, I think that is enough for forest riding. But I would like to have it slightely more agressive from zero, The power seems to be there but comes after a short "ketchup effect".. I want to get better response/ torque-feeling, I don't really know what could be optimized. (the battery I have is a 72V said to have: Maximum Continuous Discharge Current (A) 50A, instantaneous Maximum Discharge Current (A) 150A )
Please have a quick look at the print screen pictures below of what is say now, what do you recomend me to change? :
(https://i.imgur.com/gcDZ57x.jpg)
Initally it said 200rpm/s on the acceleration, I changed that to 800rpm/s now. (it won't let me to enter any higher) Think it was Big improvement. What else? What about all diffrent current settings? Shall I increase the start phase current? What is boost? What is High/mid/low speed ratio?
And a shoort video from yesterday 8)
https://www.youtube.com/watch?v=LVvD0Isf7Oc
-
Hi Rickard and(https://i.imgur.com/evDSMvT.png)to the forum.
If your battery can provide a short term maximum current output of 150 Amps, try increasing the "Battery Drawn Current limit (A)" to 150 Amps and see if the acceleration improves.
I think the boost allows additional current for a short period of time.
The High/mid/low speed ratios can only be used when a suitable 3 position switch is used to manually select the individual speed settings.
Alan
-
Thank you! I was so hopefull trying to adjust that, seemed so logical, but got disaponted when the program didn't let me to upload that, see the error message below:
(https://i.imgur.com/Di63bi2.jpg)
The maximum possible was 80, as it was before..
Took a ride in the cold anyway, works good, so fun with bumpy trail Riding, but it is way to carefull from start. If I put down one foot it is almost not possible to lean it down and make a "drift U-turn" - now when I have the winter spike/stud tires on. And very weak when I have to start in an up hill.
(https://i.imgur.com/T5a81Be.jpg)
-
Pity you cannot get more than 80a. Try also to increase phase amps to see if you get any more acceleration from stand still. Especially the starting phase current which you should match with the max phase current, this maybe holding back initial acceleration as 60a is low.
Also try changing your throttle max to 4.0v , 3.2 seems low to me, there maybe a little more throttle to be used.
-
Yes it feels lika a limit, is it because 72x80 almost is 6000w as the rated motor peak power? Or what does that error message mean? (A):1.0 iÜ x iÜ ? The battery could give more...
Do you mean "start phase current (A)" When you Said phase amps?
How is it with throttle voltage?
I will also try a 55 tooth rear sprocket, but assume it will not change much to My existing 54 tooth..
-
Yes it feels lika a limit, is it because 72x80 almost is 6000w as the rated motor peak power? Or what does that error message mean? (A):1.0 iÜ x iÜ ? The battery could give more...
Do you mean "start phase current (A)" When you Said phase amps?
How is it with throttle voltage?
I will also try a 55 tooth rear sprocket, but assume it will not change much to My existing 54 tooth..
Yes, see if you can up the 'starting phase current' to match the max phase current.
If you have a hall sensor throttle the voltage range is usually zero to about 4v. So at present you have 'throttle maximum valid voltage' at 3.2v. It may not make any difference, infact it may just make the throttle a little tamer,, but its worth a try.
I don't know much about the gearing ratios and sprocket sizes , but going smaller or larger will of course change either acceleration, or top speed depending which way you go. Top speed probably wont be effected that much if more acceleration is needed.
Great bike btw
-
Hi Rickard
I have a similar build and am getting the same response. The wheel will not spin on take off from stationary under full throttle. It takes to about mid rpm range to have good torque. It's not like it isn't quick, and if you are already moving it will throw some dirt in the corners but initial take off is not great.
Wondering if you worked out any more setting changes that were helpful.
Did you try increasing starting phase amps?
Thanks
Murray