2005 FP Pinion

[Joe Johnson]

Originally Posted by Joe Ross

Dr. Joe, did you measure it already, or is this a calculated value?

I will try to get to this over the weekend. Sadly, the power supply I need to do this is back here at Delphi and the parts are in Pontiac (about 1/2 hour away).

Joe J.

[Biff]

Originally Posted by Joe Johnson

I will try to get to this over the weekend. Sadly, the power supply I need to do this is back here at Delphi and the parts are in Pontiac (about 1/2 hour away).

Joe J.

Checked ours, 13 teeth
Read the Friday Email about the Typo in the kit for the FP's. I also had the kids measure the free speed with the transmission. 144 rpm, battery fully charged, fuse, no victor. which is no surprise as last years was 130 same conditions.
Cheers
Tom Cooper
1227

[DGiandomenico]

Here are a couple measurements on our 2005 Fisher Price Motor

13 teeth; 1/2" O.D. pinion

Part ID# 74550-0642
Code: TD034701


Measured RPM*:
24,500 @ ~12V (voltage approx)
12,000RPM @ 6.0V
-11,600RPM @ -6.0V (reverse direction)
* Measured using R/C airplane hobby tach & transparent disc w/stripe


Motor Resistance**:
0.069 - 0.074 ohms

**Measured with 10A current source; 4 point measurement of 0.69-0.74 V while turning rotor between fingers

Calculated stall current from above:
162 - 173A (12V/0.069ohms; 12V/0.074ohms)


All these measurements agree well enough by those provided by Paul Copiola at

http://www.chiefdelphi.com/forums/sh...ad.php?t=32442

-David

[Max Lobovsky]

We've got another pair of

74550-0642
TD034701
13 tooth pinion
Haven't measured resistance.

We really need to get this cleared up soon because we've all got to buy some gears and sprockets and we need the correct torque/power/speed data...

[MattB703]

To take this question to the next level;

Does anyone know or want to hazard a gues as to what the pressure angle is on the gears used in the FP transmission?

Matt B

[Tristan Lall]

Originally Posted by MattB703

Does anyone know or want to hazard a gues as to what the pressure angle is on the gears used in the FP transmission?

20° (at least, that's what the old ones were). The new gears look like they have the characteristic "sharp" teeth, so short of taking measurements, I'd definitely say that that's what they are.

[Joe Johnson]

Originally Posted by Tristan Lall

20° (at least, that's what the old ones were). The new gears look like they have the characteristic "sharp" teeth, so short of taking measurements, I'd definitely say that that's what they are.

From history, I'd say you are pretty safe in saying it is a 20 Degree Pressure angle.

They typically use standard DP and pretty standard gears (no enlargements or thickening of teeth, etc.).

Joe J.

[rmmlg]

So is this 32 DP like the others?

[Tristan Lall]

Originally Posted by rmmlg

So is this 32 DP like the others?

Definitely. And I tested the mesh today with some good quality 20° PA gears, and I'm even more confident that nothing has changed.

13 T, 32 P, 20° PA