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Discussion Starter · #1 ·
Re: [EVDL] 3.5 to one gear ratio chopper. Motor recommendations.

I have a 4.736:1 ratio and an L91 motor on a 72V bike.....
http://www.evalbum.com/preview.php?vid=1231 and had no problems with motor
overheating. The Zilla 1K limited the the max current to about 700A peak
during max acceleration from a stop. 200A would give really slow
acceleration with an even lower ratio. I went this route since I live in AZ
and heat is a concern. Too many stories about PM motor meat downs. My top
speed is limited to about 50 MPH by the 72V and ratio. The ratio was
designed for 8 batteries but I could not fit them in. me

Tom Keenan <[email protected]> wrote:

> One additional thing about the Comutacar - it came stock with 135R13 tires,
> and
> the motorcycle probably has a significantly larger diameter rear tire - so
> even
> 7:1 may be too low with a small motor.
>
> My Citicar (older than the Comutacar) has a 7.125:1 axle. Works OK for
> going up
> hill, but tops out at about 45.
>
> Tom Keenan
>
>
>
> ----- Original Message ----
> From: EVDL Administrator <[email protected]>
> To: Electric Vehicle Discussion List <[email protected]>
> Sent: Tue, March 8, 2011 10:35:32 PM
> Subject: Re: [EVDL] 3.5 to one gear ratio chopper. Motor recommendations.
>
> On 8 Mar 2011 at 20:03, Lawrence Rhodes wrote:
>
> > I'm a little skeptical of the RT-200 because it is only 39 pounds.
>
> You're trying to get lots of torque from your motor at something like 1500
> rpm, IIRC. That doesn't come naturally to a 39lb motor. If you're not
> going to gear it down further, you need a low speed motor. However, low
> speed motors are usually BIG, as in hundreds of pounds. That might make
> sense for a truck or large car, but not for a bike.
>
> Even the old 1500lb Comuta-Car had lower gearing than you're using, 6.38:1.
> That had a 65lb 6hp GE motor. Mine had the optional 5.19 (IIRC) speed
> axle.
> That was OK for flat Florida, but I kept burning up brush pigtails trying
> to
> climb hills here in gently rolling northern Ohio (let alone SF). Then I
> put
> in a controller with a 350a current limit. That stopped the brush burning,
> bur I couldn't climb hills any more.
>
> WIthout much lower gearing, you're going to need a motor that's hopelessly
> big and unwieldy for a bike. I'm no bike expert so I don't know what the
> right gearing would be. However, you have examples. Look at what the
> commerical E-bike / big scooter builders are doing and emulate that.
>
> Good luck.
>
> David Roden - Akron, Ohio, USA
> EVDL Administrator
>
> = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> EVDL Information: http://www.evdl.org/help/
> = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> Note: mail sent to "evpost" and "etpost" addresses will not
> reach me. To send a private message, please obtain my
> email address from the webpage http://www.evdl.org/help/ .
> = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
>
>
> _______________________________________________
> | REPLYING: address your message to [email protected] only.
> | Multiple-address or CCed messages may be rejected.
> | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> | OTHER HELP: http://evdl.org/help/
> | OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
>
> _______________________________________________
> | REPLYING: address your message to [email protected] only.
> | Multiple-address or CCed messages may be rejected.
> | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
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>
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| Multiple-address or CCed messages may be rejected.
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| OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
 

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Registered
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70 Posts
Discussion Starter · #2 ·
Re: [EVDL] 3.5 to one gear ratio chopper. Motor recommendations.

Hi Mark,
Do you ride uphill at low speeds? I don't recall a lot of hill climbing in Tempe from my days living down there. Lawrence is in the Bay area with lots of hill climbing at low speeds. My own motorcycle is not geared all that low either and I do not have any heating issue, but I do very little low speed hill climbing. I think at 60 mph I am at about 3000 rpms.
damon

> Date: Thu, 10 Mar 2011 08:32:55 -0700
> From: [email protected].xxx
> To: [email protected]
> Subject: Re: [EVDL] 3.5 to one gear ratio chopper. Motor recommendations.
>
> I have a 4.736:1 ratio and an L91 motor on a 72V bike.....
> http://www.evalbum.com/preview.php?vid=1231 and had no problems with motor
> overheating. The Zilla 1K limited the the max current to about 700A peak
> during max acceleration from a stop. 200A would give really slow
> acceleration with an even lower ratio. I went this route since I live in AZ
> and heat is a concern. Too many stories about PM motor meat downs. My top
> speed is limited to about 50 MPH by the 72V and ratio. The ratio was
> designed for 8 batteries but I could not fit them in. me
>
>
Tom Keenan <[email protected]> wrote:
>
> > One additional thing about the Comutacar - it came stock with 135R13 tires,
> > and
> > the motorcycle probably has a significantly larger diameter rear tire - so
> > even
> > 7:1 may be too low with a small motor.
> >
> > My Citicar (older than the Comutacar) has a 7.125:1 axle. Works OK for
> > going up
> > hill, but tops out at about 45.
> >
> > Tom Keenan
> >
> >
> >
> > ----- Original Message ----
> > From: EVDL Administrator <[email protected]>
> > To: Electric Vehicle Discussion List <[email protected]>
> > Sent: Tue, March 8, 2011 10:35:32 PM
> > Subject: Re: [EVDL] 3.5 to one gear ratio chopper. Motor recommendations.
> >
> > On 8 Mar 2011 at 20:03, Lawrence Rhodes wrote:
> >
> > > I'm a little skeptical of the RT-200 because it is only 39 pounds.
> >
> > You're trying to get lots of torque from your motor at something like 1500
> > rpm, IIRC. That doesn't come naturally to a 39lb motor. If you're not
> > going to gear it down further, you need a low speed motor. However, low
> > speed motors are usually BIG, as in hundreds of pounds. That might make
> > sense for a truck or large car, but not for a bike.
> >
> > Even the old 1500lb Comuta-Car had lower gearing than you're using, 6.38:1.
> > That had a 65lb 6hp GE motor. Mine had the optional 5.19 (IIRC) speed
> > axle.
> > That was OK for flat Florida, but I kept burning up brush pigtails trying
> > to
> > climb hills here in gently rolling northern Ohio (let alone SF). Then I
> > put
> > in a controller with a 350a current limit. That stopped the brush burning,
> > bur I couldn't climb hills any more.
> >
> > WIthout much lower gearing, you're going to need a motor that's hopelessly
> > big and unwieldy for a bike. I'm no bike expert so I don't know what the
> > right gearing would be. However, you have examples. Look at what the
> > commerical E-bike / big scooter builders are doing and emulate that.
> >
> > Good luck.
> >
> > David Roden - Akron, Ohio, USA
> > EVDL Administrator
> >
> > = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> > EVDL Information: http://www.evdl.org/help/
> > = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> > Note: mail sent to "evpost" and "etpost" addresses will not
> > reach me. To send a private message, please obtain my
> > email address from the webpage http://www.evdl.org/help/ .
> > = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> >
> >
> > _______________________________________________
> > | REPLYING: address your message to [email protected] only.
> > | Multiple-address or CCed messages may be rejected.
> > | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> > | OTHER HELP: http://evdl.org/help/
> > | OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
> >
> > _______________________________________________
> > | REPLYING: address your message to [email protected] only.
> > | Multiple-address or CCed messages may be rejected.
> > | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> > | OTHER HELP: http://evdl.org/help/
> > | OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
> >
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> _______________________________________________
> | REPLYING: address your message to [email protected] only.
> | Multiple-address or CCed messages may be rejected.
> | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
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> | OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev

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_______________________________________________
| REPLYING: address your message to [email protected] only.
| Multiple-address or CCed messages may be rejected.
| UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
| OTHER HELP: http://evdl.org/help/
| OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
 

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Registered
Joined
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70 Posts
Discussion Starter · #3 ·
Re: [EVDL] 3.5 to one gear ratio chopper. Motor recommendations.

There are a few "hills" gong over freeway and on free way loops and I do
them at 25MPH or higher so I guess I don't get much heating from low speed
climbs. me

damon henry <[email protected]> wrote:

>
> Hi Mark,
> Do you ride uphill at low speeds? I don't recall a lot of hill climbing in
> Tempe from my days living down there. Lawrence is in the Bay area with lots
> of hill climbing at low speeds. My own motorcycle is not geared all that
> low either and I do not have any heating issue, but I do very little low
> speed hill climbing. I think at 60 mph I am at about 3000 rpms.
> damon
>
> > Date: Thu, 10 Mar 2011 08:32:55 -0700
> > From: [email protected]
> > To: [email protected]
> > Subject: Re: [EVDL] 3.5 to one gear ratio chopper. Motor recommendations.
> >
> > I have a 4.736:1 ratio and an L91 motor on a 72V bike.....
> > http://www.evalbum.com/preview.php?vid=1231 and had no problems with
> motor
> > overheating. The Zilla 1K limited the the max current to about 700A peak
> > during max acceleration from a stop. 200A would give really slow
> > acceleration with an even lower ratio. I went this route since I live in
> AZ
> > and heat is a concern. Too many stories about PM motor meat downs. My
> top
> > speed is limited to about 50 MPH by the 72V and ratio. The ratio was
> > designed for 8 batteries but I could not fit them in. me
> >
> > On Wed, Mar 9, 2011 at 4:12 PM, Tom Keenan <[email protected]> wrote:
> >
> > > One additional thing about the Comutacar - it came stock with 135R13
> tires,
> > > and
> > > the motorcycle probably has a significantly larger diameter rear tire -
> so
> > > even
> > > 7:1 may be too low with a small motor.
> > >
> > > My Citicar (older than the Comutacar) has a 7.125:1 axle. Works OK for
> > > going up
> > > hill, but tops out at about 45.
> > >
> > > Tom Keenan
> > >
> > >
> > >
> > > ----- Original Message ----
> > > From: EVDL Administrator <[email protected]>
> > > To: Electric Vehicle Discussion List <[email protected]>
> > > Sent: Tue, March 8, 2011 10:35:32 PM
> > > Subject: Re: [EVDL] 3.5 to one gear ratio chopper. Motor
> recommendations.
> > >
> > > On 8 Mar 2011 at 20:03, Lawrence Rhodes wrote:
> > >
> > > > I'm a little skeptical of the RT-200 because it is only 39 pounds.
> > >
> > > You're trying to get lots of torque from your motor at something like
> 1500
> > > rpm, IIRC. That doesn't come naturally to a 39lb motor. If you're not
> > > going to gear it down further, you need a low speed motor. However,
> low
> > > speed motors are usually BIG, as in hundreds of pounds. That might
> make
> > > sense for a truck or large car, but not for a bike.
> > >
> > > Even the old 1500lb Comuta-Car had lower gearing than you're using,
> 6.38:1.
> > > That had a 65lb 6hp GE motor. Mine had the optional 5.19 (IIRC) speed
> > > axle.
> > > That was OK for flat Florida, but I kept burning up brush pigtails
> trying
> > > to
> > > climb hills here in gently rolling northern Ohio (let alone SF). Then
> I
> > > put
> > > in a controller with a 350a current limit. That stopped the brush
> burning,
> > > bur I couldn't climb hills any more.
> > >
> > > WIthout much lower gearing, you're going to need a motor that's
> hopelessly
> > > big and unwieldy for a bike. I'm no bike expert so I don't know what
> the
> > > right gearing would be. However, you have examples. Look at what the
> > > commerical E-bike / big scooter builders are doing and emulate that.
> > >
> > > Good luck.
> > >
> > > David Roden - Akron, Ohio, USA
> > > EVDL Administrator
> > >
> > > = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> > > EVDL Information: http://www.evdl.org/help/
> > > = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> > > Note: mail sent to "evpost" and "etpost" addresses will not
> > > reach me. To send a private message, please obtain my
> > > email address from the webpage http://www.evdl.org/help/ .
> > > = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> > >
> > >
> > > _______________________________________________
> > > | REPLYING: address your message to [email protected] only.
> > > | Multiple-address or CCed messages may be rejected.
> > > | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> > > | OTHER HELP: http://evdl.org/help/
> > > | OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
> > >
> > > _______________________________________________
> > > | REPLYING: address your message to [email protected] only.
> > > | Multiple-address or CCed messages may be rejected.
> > > | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> > > | OTHER HELP: http://evdl.org/help/
> > > | OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
> > >
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