[Bowser330]

I read an article that Black Currant's siamese 9" motors were 10,000$....

Seeing as 9" Series motors can be found in junkyards for a few hundred dollars each, I am wondering what the other 9,500$ is for...even purchased refurbished/new for EV normal use they can be purchased for 1,600$ each, so 2X = 3,200$...so to siamese the motors and upgrade them further costs...6,700$?? I found a link advertising "Jimpluse9" for ~5000$ in 2008. Did the price really double in 3 years?

I have been searching the web for details as to what exactly is done to the motors to upgrade them for drag racing durability, it seems the "tricks" aren't being discussed very openly, I guess to keep the advantage and the price mark-up with the motor builders...

1: Advanced timing
2: Insulation (liberal nomex paper wrapping)
3: External cooling/blower fan
4: Newer better "Heavy Duty" Brushes
5: Additional Kevlar banding
6: Higher temp wiring
7: Higher rpm bearings
8: Higher voltage terminals
9: Field Weakening
10: Add brushes

[somanywelps]

Originally Posted by Bowser330

I read an article that Black Currant's siamese 9" motors were 10,000$....

Seeing as 9" Series motors can be found in junkyards for a few hundred dollars each, I am wondering what the other 9,500$ is for...even purchased refurbished/new for EV normal use they can be purchased for 1,600$ each, so 2X = 3,200$...so to siamese the motors and upgrade them further costs...6,700$?? I found a link advertising "Jimpluse9" for ~5000$ in 2008. Did the price really double in 3 years?

I have been searching the web for details as to what exactly is done to the motors to upgrade them for drag racing durability, it seems the "tricks" aren't being discussed very openly, I guess to keep the advantage and the price mark-up with the motor builders...

1: Advanced timing
2: Insulation (liberal nomex paper wrapping)
3: External cooling/blower fan
4: Newer better "Heavy Duty" Brushes
5: Additional Kevlar banding
6: Higher temp wiring
7: Higher rpm bearings
8: Higher voltage terminals
9: Field Weakening
10: Add brushes

Kostov dual 9"s are pretty cheap...

[Bowser330]

Originally Posted by somanywelps

Kostov dual 9"s are pretty cheap...

Im not sure they have all the performance upgrades that the Jimpluse9's do...

[somanywelps]

Originally Posted by Bowser330

Im not sure they have all the performance upgrades that the Jimpluse9's do...

That's probably why they're so costly.

Remember man-hours for labor and R&D.

[major]

Originally Posted by Bowser330

I read an article that Black Currant's siamese 9" motors were 10,000$....

What would be the cost of a modified VW engine and transmission which could yield similar performance on the track?

[Bowser330]

Originally Posted by major

What would be the cost of a modified VW engine and transmission which could yield similar performance on the track?

hahaha good point...I don't think that's even possible and definitely not reliably with only 10K$....

Major, everyone knows you know your motor tech...

Is there really some kind of magic that goes into the siamese impulse 9's?

If the cost is really driven by the machining & assembly time/labor to siamese the motors then I will understand that, I am more interested in knowing the specific motor upgrades, bearings, terminals, kevlar, latest brushes, etc (the list above) is that really it?

For example, I know what a dual armature is, I've seen the pictures showing two armatures on a single shaft, each with their commutators on the far ends....


however, I have not been able to find a good picture on the web of a "dual commutator", which Netgain has advertised...can you help describe that to me? Also, how does that help the voltage handling of the motor?

I found this picture but I am not sure it helps much...

[major]

Originally Posted by Bowser330

Is there really some kind of magic that goes into the siamese impulse 9's?

Nah, it's all driver skill

Originally Posted by Bowser330

however, I have not been able to find a good picture on the web of a "dual commutator", which Netgain has advertised...can you help describe that to me? Also, how does that help the voltage handling of the motor?

Sorry, I have no idea what that is all about

My point would be that these electric motors used to set these "records" aren't excessively costly. I don't think John has "built" motors in his DCPlasma

[Bowser330]

Originally Posted by major

Nah, it's all driver skill



Sorry, I have no idea what that is all about

My point would be that these electric motors used to set these "records" aren't excessively costly. I don't think John has "built" motors in his DCPlasma

very true, i believe he just has two off the shelf warp9's coupled together...hmmm

[Plamenator]

A dual commutator is actually a longer one.
Normally commutators accomodate 8 brushes in 4 rows.
A longer one can take 12 or 16 brushes (still in 4 rows but 4 in a row).

This is done in order to spread the current and in some cases results in lower commutator and brush temperature. It can be done if arcing is a problem or if amps per sq.mm of brush surface were over the norm.

Making it longer has 2 drawbacks:
1) More brushes mean more friction so if arcing/amps were not a problem initially, going to 16 brushes actually heats up the commutator.
2) A longer commutator experiences more centrifugal force and is more prone to exploding.

Actually our K13" DirectDrive was with 16 brushes initially.
We reduced those to 8 and shortened the commutator to achieve higher continuous rpm.
Result was very good.
But this was an interpoled motor to start with so it never had arcing problems.