Motor Collection - Old School Horsepower

[dinglem]

It is great... until you open up the motors and find the wrong armature... then you have to try to source the correct one! Mick also clearly marked his armatures so his are easy to sort. As you say, it makes life a whole lot better rather than having to guess everything or use the inductance meter to determine the wind.

[MarkyDents]

Did all the aluminum endbell Team Checkpoint motors have such adorable sized brushes ??

[dinglem]

Yup, slot brushes.... harking back to the slot car origins of many of the RC motor builders. Quite a few motors can be found with modular endbell slot conversions - there were a few companies who offered them. I try to collect them whenever i come across them. I am waiting on delivery of an early Trinity example at the minute.

I also have a rare example of a pre-Platinum Series HPI-Uno based Checkpoint which also has slot brushes, although in modular endbell format.

The Trinity slot-converted examples are the best known after the Checkpoints. I have a few MG examples too.

Some of the early Igarashi motors had modular slot brush conversions fitting inside their rather plain looking plastic endbells too. Something I am always on the lookout for.

[TheDiamondOne]

Did all the aluminum endbell Team Checkpoint motors have such adorable sized brushes ??

I have to say, those tiny brushes look the part of pure race. But i prefer the standard size. They last way longer and can rip just as hard. Our Brutus motor is proof of that.

[dinglem]

There is certainly a performance difference, hence why they began messing around with cut brushes later on to essentially achieve the same thing, and also Gil Losi Jr. won the '85 off road Worlds using a Kyosho-based Trinity motor with the slot brush modular endbell.

That, and the looks, is why they sell at a premium over the boggo standard brush design. Similarly the Checkpoint range, which always seem to be in high demand.

Torque, revs and amp draw all change.

[TheDiamondOne]

Martin i dont discredit your opinion. However, we had the gil losi 85 ifmar motor nip with the slot car brushes. It wasnt until we put a trinity aluminum endbell on it with full size brushes that it came to life. Just our experiences mind you. But this Barely used Brutus dry mag with big brushes sealed the deal.. Anyway, just me and Dereks experiences. Dig all your work and knowledge!

[dinglem]

My biggest surprise based on my own experiences is the vast chasm of performance difference between off-the-shelf motors and the proper full-blown team provided motors.

I remember the whole time i was racing at club level the fastest motor i came across was (coincidentally) a 17turn Revolution motor ran buy a guy called Peter Smith at our local club. After the meeting, which he won, we got it out and he agreed to run it on the dyno. It gave 31,000rpm which at that time was the highest revving motor i had come across. We are talking around 87 or early 88 here i would guess.

I had not seen anything like that before, but once sponsored by MG the motors i subsequently received totally buried that figure. We regularly saw max revs up in the 40,000's, and the batch i received from Team Schumacher driver (who was also sponsored by MG for the Florida International event in the early 90's) saw one motor max out the dyno, which had a max rev count of 50,000rpm, so it was putting out way over that. The needle was maxed to the right at what looked to be >60,000rpm. I guess the time put in to those team motors by the motor builders was what made all the difference. I don't think you could ever buy that kind of performance off the shelf. When i sent it off to my motor builder for a full zap, skim and magnet re-alignment he could not believe what he was seeing. I really need to get it on to my Integy digital dyno to find out how far over 60,000rpm it is actually going.

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10s.jpg (73.7 KiB) Viewed 921 times

Going back to the slot brush conversation - i would guess that when the Yokomo style open endbell design came about, with milder winds and lower performance winds being the norm, the small gains from slot brushes would have made a difference at the highest level. As winds dropped due to better cell availability, then larger brushes may have proved advantageous. There are articles and articles on the benefits of various cut brush designs for performance, and to me these just point back to the slot brush days. I don't think those guys would have been worried about how much longer the larger brushes lasted.... back then motor rebuilds, skims and new brushes every race or two were considered normal.

The other interesting factor nobody really seems to consider is torque figures. Max revs mean nothing without torque. Interesting for me is the motor which has given my my highest torque reading on the Torque meter is an very old Igarashi MG 26Single modified... one from the very infancy of modified motors. It had been popped open, machined for ball-races and had vent holes drilled in the sides of the can, and was then hand (re)wound by Mick Goddard. The amp draw is super low at 1.4amps but the torque is 50% higher than any other motor i have ever tested.

The best all round performer i have is a Reedy BK Select which was sent to team Reedy driver Jimmy Davis. It shows 51,000rpm, with a medium amp draw of 3.9amps but has a relatively high torque reading also.

[dinglem]

Just for reference, here are two early pre-Yokomo endbells which have been converted to slot brushes. This service was offered by Checkpoint and sold through Bolink.

I have located these two after much hunting but still haven't sealed the deal to get my hands on them yet....if anybody has such an endbell kicking about then please do let me know. Proper old school motor modification. These would have been a massive step forward from the old flat bent metal pressure plate brush systems previously seen, mainly because they were rebuildable and you could adjust spring tension. I guess the guys doing this went on to modifying the early open endbell motors using this same method.

Nobody really looks back at the onset of motor mods and these early worked-over Igarashi and Mabuchi motors, but i find that era fascinating.

[MarkyDents]

Picked these up a ways back now, is the one on the left a Team Checkpoint as well ?

[dinglem]

Yes it is.

Got pics of both ends? Base should have long slots.

[juicedcoupe]

As winds dropped due to better cell availability, then larger brushes may have proved advantageous.

Trinity P-94 and later Kyosho motors come to mind. With square 4.9 and 5mm brushes, instead of 4X5 mm stand-up and laydown designs.

I could see the advantage of larger brushes being particularly useful in 7 cell stadium trucks, as their increased surface area would provide better current handling and cooling.

[V12]

I have my original WetMag IV which came with the engravings from when i opened the packet so I can confirm they were there from the factory.

They all look the same. I have a WetMag IV, WetMag II and an I now all of which have them.

I actually make a point of looking out for the markings now and if i buy others i will ensure they are the marked examples.

The markings were made at the Losi factory indeed.
I have no idea why some motors were not marked. But I think the missing markings were just a thing of randomly forgotten or the motors were made by an other person than their motor builder Randy Hunter.

[V12]

Picked these up a ways back now, is the one on the left a Team Checkpoint as well ?A752F24D-83FA-463F-9B14-46AAB0917CE3.jpeg

As long as this motor got slot brushes.
A few of the Checkpoint cans were sold to Fantom who sold them along with their modified armatures.
But these motors came with a standard size brush setup.

I have such Fantom motor but did not found the time so far posting at the museum.

[V12]

Just for reference, here are two early pre-Yokomo endbells which have been converted to slot brushes. This service was offered by Checkpoint and sold through Bolink.

slot igarashi.jpg


I have located these two after much hunting but still haven't sealed the deal to get my hands on them yet....if anybody has such an endbell kicking about then please do let me know. Proper old school motor modification. These would have been a massive step forward from the old flat bent metal pressure plate brush systems previously seen, mainly because they were rebuildable and you could adjust spring tension. I guess the guys doing this went on to modifying the early open endbell motors using this same method.

Nobody really looks back at the onset of motor mods and these early worked-over Igarashi and Mabuchi motors, but i find that era fascinating.

Have not been much at the forum for a couple of months and find lots of interesting postings now.

Regarding your posting about Checkpoint and BoLink.
When Jim Greenemeyer of Checkpoint went into making R/C motors, he made also BoLinks top of the line modified motors. These were sold as 'BoLink Stage ... ' motors. Their full name actually was with a number added, Stage 1 to Stage 5 overall. The Stage number represented the work which went into the specific motor.
I think they were quite the same as his own motors beside the sticker.
The highest Stage number was a full modified + the brush conversion.
I´m just not sure currently if all of his motors were sold through Bolink. But the special modular endbell was available through BoLink for sure.
https://classicrc.wordpress.com/motors/checkpoint-2/checkpoint-igarashi-modular-endbell/

I have such endbell along with the card header.
But such endbell conversion as a standalone part is super rare, especially the BoLink version.
All of the Checkpoint stuff sold through BoLink with BoLink sticker or card header is super rare, because it was just for a very limited time frame.
Later Checkpoint stopped making motors for BoLink.
There are a lot of facts about Checkpoint which are not known to most guys today.
The older guys who have been involved with slot cars might know them.
But it is a different story and offtopic here.

Actually the main reason for inventing the modular endbell with slot brushes was the fact, the original brushes of Igarashi motors were not really suited to carry a lot of current. The compound used for making those brushes was not up to the specs needed for the job, for hot modified armatures.

The metal plate spring used for the original brush system was not very good either, but this was not the main reason. Because you could reinforce that flat spring to carry more current or make it stiffer as it had been done by other companies as Delta.
But making the modular endbell was something different and much more work involved. So it was quite expensive even back in those early days.

I found a couple of the modular endbells, brushes and springs. But don´t ask me how many years I spent for searching. And how much $

But I´m addicted to those early motors. Especially the Igarashis as such original motor was never intended for R/C use and motor builders had to invest much more knowledge and work in those, than for any others later.
My favorites are Delta, Checkpoint, Trinity, Parma Ferrari, Sping, the crazy Moebus motor which goes even one step further than the Checkpoints.

[Phin]

What brand/size slot car motors were these brushes from? I have a pack of Bolink Stage IV brushes + springs, and was going to repro my own endbell if I can find the right brush holders.