October 9, 2019 New Motors for a Rivarossi Cab Forward

I have 12 Rivarossi SP Cab Forwards, 4 Rivarossi SP AC-9s (kitbashed Cab Forwards) and 6 Y6Bs.  I kitbashed two into AC-3 Cab Forwards two MC-1 and two are still Y6Bs.

Of my 22 Rivarossi articulateds I bought one Cab Forward new in the box and one was a gift from a RR Buddy, 20 were clunkers bought at either the Bakersfield yearly Train Show or off eBay.

The Rivarossi articulateds can be restored to fine running locomotives.  When re-motoring them with rare Earth magnet can motors they will except up to 10 additional ounces of weight without heating the motor.  The combination of new motors and added weight they become super pullers at 5 to 7 ounces of drawbar.  Out of the box their drawbar spec was 2.8 ounces.

Before my modifications an out of the box Cab Forward would have a hard time pulling a half dozen empty flat cars up my 3% grades without wheel slip.  After my mods they will easily pull as many cars as I could put behind them with 6 to 8 ounces of drawbar.

As probably most of you with Rivarossi articulated locomotive experience know they have a slight to moderate wobble when running.  I have determined that the wobble is caused by the Rivarossi driveline.  Driving two gear boxes with one motor and a driveline between them the frame tends to wobble.  By installing two motors, one for each gearbox the wobble isn’t there.  The two motor Rivarossi also has more traction even without adding weight, the drawbar with two motors is 3.4 ounces.  I tried to determine if the second motor added some weight but found out that a dual motor frame weighs slightly less than the original Rivarossi frame.

The original Rivarossi could and did draw close to one amp at full throttle.  A dual Canon EN22 or Mabuchi SF-266 motored frame draws less than 500ma with a dozen cars behind them and that only increases to 620ma pulling my 3% grades.   

As most of you out there know the Canon EN22 motor is getting very hard to find since the passing of Eldon Shirley, AKA Motorman.

The SF-266SA is a bit smaller then the Canon EN22, the white plastic on the rear of the motor can be removed decreasing the length by 3.5mm.  As delivered the motor power contacts are removable, they come in a separate envelope.  By removing the white plastic piece there are a pair of brass lugs to solder the wires to. 
 
A fellow on the Model Railroad Forum put me onto the Mabuchi SF-266SA motor and after putting a pair through some vigorous testing it came out very close to equal to the Canon EN22.

I removed the two Canon EN22 motors from my Rivarossi Cab Forward 4126 and Installed two Mabuchi SF-266SA motors and it matches the pair of Canon EN22s in my AC-9 3807 in speed and power.  My AC-9 3807 is a kitbashed AC-10 with a pair of Canon EN22 motors.  Both locomotives have 10 ounces of added weight and the drawbar is 5.8 ounces on both.

I didn't remove the white plastic piece on these two.

The bottom line is the Mabuchi SF-266SA looks like a very good motor for remotoring HO locomotives.  I initially bought 2 of the SF-266SA motors off eBay for $1.92 each and $2.50 S&H.  When I found out how well they work I ordered 10 more.  The total of 10 motors with S&H was $21.77.  The first two arrived from China 11 days after I placed the order.

As of October 2, 2019 there seems to be an abundance of them available but I thought the Canon EN22 were in abundance too.  I bought one Canon EN22 initially to test it for $1.19 State Side.  It was suburb so I ordered 20 more, a couple of days later I placed a second order for 20 more, I received 11 because they were sold out.

I bought a few from Motorman over the years but not at that price.