Differences between high end ESC's and cheap ones for Lehner motors?

[kfxguy]

Well I’ll insert my opinion. Maybe the Lehner motors aren’t really a sport motor. I think they are really made for all out speed. Maybe not, but in any application I’ve used them in with regular running they just haven’t lasted. And these motors I refer to weren’t just in my hands, one guy isn’t a speed junkie and he just ran his boat for fun. The shaft moved in it. Personally I don’t like thrust bearings or washers in my boats because that’s another part to fail or wear out. When I build something and put my name on it, I prefer to have no problems so I try to do what I know works. So far I’ve had the absolute best luck with cheap tp motors and neu motors. Neu used to have shorting problems in the leads coming out the motor but they fixed that by putting beer insulating sleeves where the leads exit the end bell. I feel like I can accomplish any goal I have with either of those motors and not have to spend $400 on a motor. Same thing goes for escs. While the mgm look purty and they drive quite nice, I don’t require them in any of my builds unless my customer requests it. My go to escs for now are the sf300 and sf220 until something else better comes along. I really like the new X series. Hopefully castle comes through with something soon.


Whoops I went a little off subject. Sorry. My answer to the original question is I’ve used castle, seaking 180 and swordfish and mgm on Lehner motors. They all worked fine.

[srislash]

Well Travis, I will agree on the LMT and sport application to an extent. They seem to be fine in normal ‘sport’ situations (30k’ish) but in hot setups they are just too compact and dense to dissipate the heat internally so it just builds till failure. Seen it thru you a couple times and on Steve’s big mono.

[kfxguy]

Well Travis, I will agree on the LMT and sport application to an extent. They seem to be fine in normal ‘sport’ situations (30k’ish) but in hot setups they are just too compact and dense to dissipate the heat internally so it just builds till failure. Seen it thru you a couple times and on Steve’s big mono.

Yea that may be the case. One of them that failed I took it apart and inspected it. The glue on the windings melted off. Another one I had the shaft came out of it. I think I still have it. I could probably use some sleeve retainer on it but I don’t really care to use it on anything. It’s a cool looking paperweight tho. Lol.

I but they last a lot longer in a twin because the stress will be less on them, both the heat and the pushing forces on the shaft will be less.

[TRUCKPULL]

This holds up Larry? I’m just about to mainden AWB and could install some thrust bearings I guess. Anybody know where to get 8mm ID ones?

I have never had a thrust bearing fail, I have never had a shaft shift in a motor, I run a thrust bearing in every boat I own or have built.
I have seen a shaft shift in a brand new NEU motor first run- NO thrust bearing.

The bearings in any motor are NOT designed for the amount of lateral thrust that we put on them in boats, that is why you should run a thrust bearing between the coupler and the motor in all boats.
Air tool oil, - I use a small needle syringe to oil my bearings, I do this almost every run.

8mm thrust bearings at OSE

https://www.offshoreelectrics.com/proddetail.php?prod=boc-f8-16g

Larry

[jim82]

How do you go about getting a thrust bearing to work on the TP shaft that is turned down?

[srislash]

I have never had a thrust bearing fail, I have never had a shaft shift in a motor, I run a thrust bearing in every boat I own or have built.
I have seen a shaft shift in a brand new NEU motor first run- NO thrust bearing.

The bearings in any motor are NOT designed for the amount of lateral thrust that we put on them in boats, that is why you should run a thrust bearing between the coupler and the motor in all boats.
Air tool oil, - I use a small needle syringe to oil my bearings, I do this almost every run.

8mm thrust bearings at OSE

https://www.offshoreelectrics.com/proddetail.php?prod=boc-f8-16g

Larry

Thanks Larry

[TRUCKPULL]

JIMMY
If you are asking about the 8mm motor shaft that is turned down to 5mm

I use the same motor TP4050, My motor mount is 1/8" thick aluminum, at this thickness only the 5mm shaft sticks out.
The hole in it for the motor shaft is 21/64" ( just enough side clearance so the 8mm stub that sticks out of the motor does NOT rub.

Now your 5mm thrust bearing mounts between the coupler and the face of the motor mount.

Larry

[jim82]

Gotcha. My situation is different with the motor mounted it will slide through the mount. I'm going to have to figure something out or just keep using without one. All my other boats have one

[TRUCKPULL]

Jimmy

In that case, I have seen people use a 1/16" to 1/8" thick aluminum plate, 1/2" by about 1 1/4" long
With a center hole just to clear the shaft, and two 3MM holes to line up with the motor mount holes.
It then mounts on the front of the motor mount attached with the motor mount screws, (adjust screw length to suit).
The thrust bearing then goes between that plate and the coupler.

Larry

[jim82]

Sounds like a plan thanks man

[dmitry100]

Will a thrust bearing hold up at 60k rpm loaded though?

I wonder if a thick teflon washer would hold up if used instead of a thrust bearing or just minimize the space between drive dog and drive to 2-3mm given that theres already a teflon washer there as well. A 6 inch flex cable shouldn't tighten up all too much to cause any extra heat at the drive dog right ?

[TRUCKPULL]

The Thrust bearings that we are talking about go between the motor and the coupler.

https://www.offshoreelectrics.com/proddetail.php?prod=dh-53136

They are rated about the same RPM as any motor bearing. But they are designed for THRUST where the motor bearings are not.

NEVER ever use them between the Strut and the drive dog.

You can put a Teflon washer between the strut and the drive dog if you want to,
But you still have to leave the proper space between these two, to compensate for shrinkage in the cable.
The rule of thumb for cables is. the Dia. of the cable for every 10" to 12" of length.
So if you have a 11" long 0.187" or 3/16" Dia. cable --- you leave a 3/16" space.

For high power or High RPM unite -- I would leave a little more space then I stated above.
The torque that these units put out is way higher then for Sport Or Racing Boats.


Larry

[dmitry100]

If my 3/16 flex cable is only about 6 inches ... would 3-4mm technically be sufficient space between drive dog and strut ?

It is high rpm about 60k loaded ... but I'm running twins with 42mm props and LMT 1950/5's

[TRUCKPULL]

"It is high rpm about 60k loaded"

My speck on Dia. size for every foot of length, is for racing about 30k loaded.

You are running twice the load, That does not mean twice the gap per foot.
It is probably a multiple of that. Meaning more then twice.

Larry

[dmitry100]

But how much more can a 6 inch cable possibly tighten though past 5-6mm ?