Agni motor tuning and racing
- Thread starter Jozzer
- Start date
Doctorbass
100 GW
I have set the max peak current setting on the zero motorcycle MBB software to 500A since 2 days ( previous was 390A) Actual voltage ( max) of my 2011 DS is 58V ( sag to 54V full load) and it work pretty well.
Jozzer if i upgrad eto 84V like Luke recomamnded to get the full potential of that motor, Would it be necessary to decrease the battery current on the controller to avoid arcing like you said ?
Doc
Jozzer if i upgrad eto 84V like Luke recomamnded to get the full potential of that motor, Would it be necessary to decrease the battery current on the controller to avoid arcing like you said ?
Doc
Jozzer
100 kW
Hi Doc,
Probably wise, it's hard to reach above 350A at that voltage without some sparks. Give it a good 2mm of advance timing also..
Cheers,
Steve
Probably wise, it's hard to reach above 350A at that voltage without some sparks. Give it a good 2mm of advance timing also..
Cheers,
Steve
Doctorbass
100 GW
Jozzer said:
All right! Thanks for the advice Jozzer
Doc
Is the problem the battery voltage or the EMF of the motor? if you have a controller which supports "mapping" different max current at different RPM, could you set it to 500A up to like 3500RPM, and then linearly decrease to 350A at 5500RPM, or similar?
Jozzer
100 kW
The problem is arcing at the brushes at higher RPM as they start to skip amoungst other things. Setting a lower battery current is a reasonable solution, since it will only start to restrict motor current as it nears 4000rpm or so - so is effectivly "mapping" as you put it..
Ahh, I see now that you were writing about battery current limit from the beginning. So you can have 500A motor current, and 350A battery current. Makes sense. Thank you.
Earlier in the thread there was some info about the pico amps brush holder. It contains springs that makes the brushes more stable. Can you use higher currents at high RPM with that one installed?
Earlier in the thread there was some info about the pico amps brush holder. It contains springs that makes the brushes more stable. Can you use higher currents at high RPM with that one installed?
Jozzer
100 kW
I've never tried that holder, but I have experimented with all sorts of spring grade - tbh the Agni standard fitted springs seem to do the best job.
What does make a huge difference is the state of the commutator. After abuse the surface becomes a little uneven, which causes more brush bouncing - so to get the best out of them it is wise to resurface the commutator regularly with a commutator cleaning stick, making sure to "run it in" again before again abusing it too much (so that a protective film forms on the copper surface).
What does make a huge difference is the state of the commutator. After abuse the surface becomes a little uneven, which causes more brush bouncing - so to get the best out of them it is wise to resurface the commutator regularly with a commutator cleaning stick, making sure to "run it in" again before again abusing it too much (so that a protective film forms on the copper surface).
The springs are not the ones pushing the brushes against the commutator. They are put inside the brush guide to stop brushes from moving "rattling around" in there.
Another question. I burned my Alltrax 7245 by connecting the oscilloscope ground to Batt+ while being connected to my stationary computer. Lots of smoke, and for some reason it put full throttle to the Agni. So the motor went full speed while sitting on the floor of my apartment. It twisted all cables, and dragged the controller, battery, and everything down from the table. Fortunately, while doing that, the battery got unplugged, so everything stopped, except a fine mist of smoke which left an aromatic smell in the apartment for a day or two.
So now I'm looking for a controller. Which controller do you recommend?
My plan is to make a really light racing bike intended to be fun on track days and such. I'm dreaming about super high corner speeds with the smooth motor, and a top speed of like 130-150km/h, limited by gearing and not power. This should make both the motor and myself able to rest for a while on the straight.
The Alltrax SPM series looks nice. Have you tried it?
Another question. I burned my Alltrax 7245 by connecting the oscilloscope ground to Batt+ while being connected to my stationary computer. Lots of smoke, and for some reason it put full throttle to the Agni. So the motor went full speed while sitting on the floor of my apartment. It twisted all cables, and dragged the controller, battery, and everything down from the table. Fortunately, while doing that, the battery got unplugged, so everything stopped, except a fine mist of smoke which left an aromatic smell in the apartment for a day or two.
So now I'm looking for a controller. Which controller do you recommend?
My plan is to make a really light racing bike intended to be fun on track days and such. I'm dreaming about super high corner speeds with the smooth motor, and a top speed of like 130-150km/h, limited by gearing and not power. This should make both the motor and myself able to rest for a while on the straight.
The Alltrax SPM series looks nice. Have you tried it?
Jozzer
100 kW
Well, seems to me that the extra springs would increase drag on the brushes reqired direction of travel in an unpredictable manner, possibly creating new problems - but like I say, I've not tried one myself! Of course the added springs would do nothing to correct a poor commutation surface, which is the main cause of brush bounce..
I don't really rate any of the current crop of controllers as a perfect match for an Agni - the Alltrax don't quite reach a high enough voltage and have no regen, and Kelly's are far too unpredictable and with a lack of support for the problems you are SURE to have. Of the 2 at least you know what your getting with an Alltrax. I've just got some of the new Alltrax models which at least have some improvements too the programming interface (I wonder if they have fixed that isolation problem - I blew a PC up too by creating a ground loop when the laptop touched chassis as well) - if your happy at 72v or less then Alltrax is probably your best bet.. If I manage to get a good test with the SPM's I'll post results here, though may be a while!
I don't really rate any of the current crop of controllers as a perfect match for an Agni - the Alltrax don't quite reach a high enough voltage and have no regen, and Kelly's are far too unpredictable and with a lack of support for the problems you are SURE to have. Of the 2 at least you know what your getting with an Alltrax. I've just got some of the new Alltrax models which at least have some improvements too the programming interface (I wonder if they have fixed that isolation problem - I blew a PC up too by creating a ground loop when the laptop touched chassis as well) - if your happy at 72v or less then Alltrax is probably your best bet.. If I manage to get a good test with the SPM's I'll post results here, though may be a while!
Doctorbass
100 GW
Jozzer, Do you happen to have some agni 95R brushes and holder?
I have one motor that need the brush replacement.
If so how much shipped to Canada G2G 2E4?
Thanks!
I have one motor that need the brush replacement.
If so how much shipped to Canada G2G 2E4?
Thanks!
Jozzer
100 kW
Hope that brush set arrived OK for you doc!
We've just got our first of the new 155r motors in - 230mm diameter, 18kg, 135mm wide - the BIG Agni is here at last!
We've just got our first of the new 155r motors in - 230mm diameter, 18kg, 135mm wide - the BIG Agni is here at last!
liveforphysics
100 TW
Jozzer said:
Awesome! Can you share no-load current at something like 25v, 50v, 75v, and 100v?
winzEracer
10 mW
- Joined
- Jun 1, 2012
- Messages
- 32
Jozzer,
Please tell us more about the 155r.
Thanks,
Brock
Please tell us more about the 155r.
Thanks,
Brock
Jozzer
100 kW
I'll get on it this week Luke/Brock - the motor's just arrived and I'm not at the workshop for a couple of days. I've not been in the loop on testing/development of this motor particularly, but the early prototypes were very promising.
One of these fatties on the back end/load of my dyno easily outlived 2 well tuned 95R's..
One of these fatties on the back end/load of my dyno easily outlived 2 well tuned 95R's..
Doctorbass
100 GW
Jozzer said:
Hello Jozzer, Thanks The brush arrived fine last week. I have confirmed that to Leslie.
:wink:
Jozzer
100 kW
Doctorbass said:
Lol - she always say's I don't talk to her enough
winzEracer
10 mW
- Joined
- Jun 1, 2012
- Messages
- 32
So I was running my 111r a bit hard and a little bit of smoke started coming out, I noticed immediately and shut it down. Pulled the brush holder and it looks ok just dirty commuter. How much damage have I done? Should I take the motor apart and clean up the commutator on the lathe? Or just clean up the commutator with the motor assembled?
EDIT: Added photos, and looked at brushes closer I thing most of the damage was to the brushes and holder, How do I know if I damaged the commutator?
Thanks,
Brock
EDIT: Added photos, and looked at brushes closer I thing most of the damage was to the brushes and holder, How do I know if I damaged the commutator?
Thanks,
Brock
major
10 kW
winzEracer said:
Post photos of it.
winzEracer
10 mW
- Joined
- Jun 1, 2012
- Messages
- 32
Here is a pic of the comutator. I was running at 100v and 425 amps for about 5-8 sec bursts doing doughnuts, got a little carried away. I have a much better brusholder to install that will handle the current better. Attached is a pic of the new brush holder with larger wedge shape brushes.
Attachments
major
10 kW
The commutating surface does not look damaged. You could use a dial indicator to check for any distortion or raised segments. If it shows smooth and flat, I suggest to run as is. I'd break-in the new brushes at no load for quite a while and take it real easy on a couple discharges (slow laps). That will seat the new brushes and improve your chances of avoiding a repeat performance :wink:
Doctorbass
100 GW
winzEracer said:
We can see on the center of the brushes that there is arcing. The center of the brish are different colors and seem to have a light valley on teh center, indicating overheat due to arcing.
Doc
