The KV listed for motors are a none load KV.

All in how you have it geared to what KV you will get under a load, I think best best you would get is around 85%.

Another thing to look at is the RPM cranking speed, Do not know if the timing curve will retard at 500 RPM.????

Milton

3W sell a compression release valve kit, if you can find space to drill and tap a 10mm thread in the head. both mechanical ( push it in before each start) or an automatic version.

That may be a great option to reduce starter motor load ( and weight in batteries and starter motor) and has the added advantage of avoiding possible engine killing hydraulic lock.

I have a couple of 3W 106 twin spark project engines drilled from the factory with 3 x 10 mm spark plug size holes in each head (2 plugs and one compression release), so if there is plenty of space and meat on top of the cylinder of your engines, I think they would be a good addition to ease starting.

i will try and take a pic of my 3w heads with 3 plug sized holes tomorrow.

edited to add.

I was looking at my DA heads, the lightened one on my 50 there isn't enough metal left to make another hole, but the old standard cylinder I took off would have enough. it would be especially easy on engines with angled plug heads.

Mike thank you for the speedy order on my second 55cc starter kit. These starters are Awesome!!! it's like jumping in your car start it up and away you go. That is how nice these starter kits work on the engines. Timing curve? rpm doesn't make a difference . They just start what a bunch of Hype, they just start!! Again Thank you Mile High RC

Originally Posted by rick dazzler

Mike and i are doing all we can to "brand this line".. he makes great engines thus far and many customers are very happy with the quality,power, and our support. this also includes constant translated night talk sessions with the owner of EME and a factory visit soon to be..I know how the market can go south with "direct sales" china websites.
EME before us had to keep his doors open somehow.. When a new engine factory starts it goes to china wholesale site's. EVEN in china starting a factory cost's a lot AND you have to move certain amounts of products to stay alive.
BUT He gets the american sales idea and has handled it very well. more so than some other lines I have dealt..Plus his engine's are of the same quality as another known brand with more power, along with other great aspects.

I dont care where you buy them but if you buy from one of us 2 in the states will back you up with the best support..
Buy it from SDS if you want but don't cry on the forums when you need technical help or parts and support because you wont get it from them....

Well said.. Well said.. "talk session" you can say that again, its a dang marathon sometimes.
I agree, we should buy what we want where we want. Have some fun because that really is what it is all about. But I personally would never expect support from a flea market... just saying...

A prior poster was hooking up a 30 amp ESC to a starter. How is that working out?

Originally Posted by jerrysu29

Mike thank you for the speedy order on my second 55cc starter kit. These starters are Awesome!!! it's like jumping in your car start it up and away you go. That is how nice these starter kits work on the engines. Timing curve? rpm doesn't make a difference . They just start what a bunch of Hype, they just start!! Again Thank you Mile High RC

Thank you!!

Originally Posted by qmulus

Back to the starters... For a brushless conversion I am looking at some brushless motors and maybe helicopter gears, maybe for a 500 class helicopter?

From what I figure from the gear teeth, the output RPM is .0387 of the input RPM (12 teeth on motor gear to 72 on the intermediate gear for .1667 reduction, then 13 on the intermediate to 56 on the prop hub gear for .232 reduction, multiplied for .0387 rounded off) . I'm not sure what RPM is required to start one of these, but I am guessing 300-500? So, if I shoot for 500RPM at the hub, I will need almost 13000 at the motor. That would mean a motor kV of around 1100kV+/- would be reasonable on a 3S lipo. Seems doable.

Can someone do a sanity check on this?

The original motor was a Johnson 550 motor. If memory serves I believe they came in 1300 and 2200Kv varieties, maybe someone can confirm.
I think your sanity is just fine and 1100Kv is at least a good starting point. Considering the low inital torque on a brushless motor (immediately at start up) and ESC timing playing a roll I wonder if going up in Kv. a little may help.

My 30 amp esc has around 100 starts on it with zero issue. Im using a 1300 mah 3s. Not sure you were referring to me as the previous user.

Originally Posted by mighty9

My 30 amp esc has around 100 starts on it with zero issue. Im using a 1300 mah 3s. Not sure you were referring to me as the previous user.

Yes I was. Nice to hear its working well.
I am jealous you have obviously been having some fun.

Originally Posted by outofdenver

The original motor was a Johnson 550 motor. If memory serves I believe they came in 1300 and 2200Kv varieties, maybe someone can confirm.
I think your sanity is just fine and 1100Kv is at least a good starting point. Considering the low inital torque on a brushless motor (immediately at start up) and ESC timing playing a roll I wonder if going up in Kv. a little may help.

Now you tell me! I was just googling Johnson motors and their website looking for specs, but didn't find much. I was hoping to replace the motor with something half the weight. The stock 550 is 205gms. I have found a couple of 300W max 1100kV motors under 100g, which I think would be ideal, assuming they have the torque. Now if I can find a gear to fit a 4mm shaft that would work with the intermediate gear...

Actually, I think the lower the kV, the higher the torque in terms of the motor.

BTW, one unexpected bonus of using an ESC is that you would have a built-in 5V regulator that you can use as the power supply for the ignition, soooo you could use that big starter battery as the ignition battery as well.

The esc i used has a bec hooks right up to the brushed motor and was around 15 bucks.Not many brushless esc for that price. Good tip on the ignition too thanks.

Hi Guys. I am new to this forum. I have just been made aware of this thread on the EME55 Electric Starter and believe that I may have something of interest to contribute. There is a lot to say so I apologize at the start for the length of this post.

To set the picture a fellow club member and I each have an AeroWorks Ultimate 50 with DLE55 engines. While GB will be retro fitting the starter to his model, I fitted it as part of the build. I ordered 2 starters as soon as they were announced by SDSHobby. While we have encounted some problems we now have a smooth running operation. Being able to drag the plane out to the flight line then casually start the engine while standing next to it is a real turn on! Full credit must be given to that very cleaver English modeler who conceived the idea which has, in my opinion, been copied but regretfully poorly engineered by EME

Firstly, there has been discussion elsewhere regarding the ignition timing as set by the factory for both the DLE and EME engines. Despite the fact that the instructions for the RCxel ingnition supplied with the engines specifies a setting of 28 degress BTDC, they come with a stated 44 degrees, although our reading indicated 36. On the un-modified engine this can be corrected by moving the Hall Sensor sideways. However, the mounting bracket for the starter precludes this so we had to move the magnet. Removing the existing magnet which was destroyed in the process proved to be quite difficult I might add. In hindsight it would have been easier to cut a new key slot, perhaps filling the original slot with JB Weld or the like.

The next problem is that the hall sensor that comes with the engine is a one part moulded unit. When the replacement Hall Sensor magnet disk is installed the pickup is some 2-3mm too far forward of the magnet. So a replacement adjustable sensor was installed.

By far the biggest problem centers around the Woodruff Key. The prop driver on the stock engine is driven by the entire exposed length of the Woodruff Key. When the supplied starter components are installed the replacement prop driver is forward of the key. The optimistic factory get around for that little problem is to have a small extension on the key. So the considerable torsional forces once carried by the full key are now expected to by borne by this tiny un-supported extension.

In my case, after some ground running and 3-4 flights it was noticed that the spinner had been forced back into the cowl. Subsequent investigation found that the extension had broken which then allowed crankshaft extension to screw the spinner bolt in, severely distorting the spinner back plate. Our initial fix was to make a new Woodruff Key using tool steel. To increase the depth of the extension and give it more support, the key way in the crankshaft was extended forward with a Dremel almost to the depth of the step down on the shaft.

This all seemed to be OK for the next couple of flights. However during some ground running of the engine which involved repeatedly blipping the throttle, as would be the case when hovering, it was noticed that the gap between the spinner and cowl had again closed up. Yep, the new key was also broken. We believe this was because the slot in the prop driver had opened up allowing movement of the key.

We now seem to have fixed the problem by firstly reducing the width of the 'magnet disk. If a 3mm replacement magnet had been used even more could be removed. This effectively moves the Sprag bearing back which in turn gives more support to the new Woodruff Key, made this time from mild steel. A new prop driver was then made, again from mild steel, which extends back over the crankshaft. (I am not as weight conscious as some of you apparently are.) Incidentally, we found that the supplied replacement prop driver was rubbing on the outer ring of the sprag housing

Now for the next part. Powering and switching the starter on. A single 4 cell 1100ma A123 pack from Hangtimes is used to run the starter. This proves to be quite sufficient for a flying session. In any case this is quickly recharged with a CellPro Multi 4 unit if need be.

We initially tried using a Turnigy brushed speed controller to do the switching but this failed after 2-3 test runs. Yes, a spooling up delay was experienced before full power was delivered to the motor. And this on a brand new DLE55 with minimal compression. A mechanical switch is now used which is controlled by a cam on the choke servo. NOTE: This will of course only work with a brushed motor.

The switch used is called a 60 amp Momentary Switch and was purchased from a local auto parts store. The cam is arranged so that the initial use of the transmitter slider (Futaba 14MZ) depresses the switch thus turning on the starter. Continuing with the slider then closes the choke. In operation, for a cold start with empty fuel lines, the slider is used over the full travel while subsequent starts require only the initial partial travel. Its a dream to use guys.

One further point. One of the connectors on the starter motor broke off during a flight due probably to vibration. Make sure you securely fix the wiring. Good thing I didn't try the stop/start party trick mid flight!

Hopefully the attached photos will fill you in. I trust that this is found to be useful.

David

Good post. I was wondering about timing adjustment as it looks like there is almost no room for adjustment of the sensor with the bracket installed. I guess it should be no surprise that it was set too advanced as the engines get supplied that way...

As for the prop hub, I was wondering about the Woodruff key myself. I have never seen anything like that used before. Did you use Loctite on the new prop hub when you installed it?

The big thing that I don't like, more than the excess weight, is that the motor was put on the same side as the exhaust. It puts even more of an imbalance of weight on that side where you really don't want it as the right thrust built into most aircraft already offsets the engine to the left side. I'm wondering if even putting the batteries, etc. on the right will be able to correct the lateral balance. I would suggest they put the motor on the right side and put the cutout where the ignition sensor is, allowing for the ability to adjust the timing properly and giving a more favorable balance.

Glad i had my starter today. Was flying the yak and did a low altitude slow speed snap and the motor quit. I quickly hit the starter button and she roared back to life . All the guys thought i did it on purpose .I was shaking so bad they soon realized i didnt.

Originally Posted by mighty9

Glad i had my starter today. Was flying the yak and did a low altitude slow speed snap and the motor quit. I quickly hit the starter button and she roared back to life . All the guys thought i did it on purpose .I was shaking so bad they soon realized i didnt.

Now that's what I'm talkn' bout! This is why I want a starter.

Originally Posted by qmulus

I would suggest they put the motor on the right side and put the cutout where the ignition sensor is, allowing for the ability to adjust the timing properly and giving a more favorable balance.

Thanks, my colleague, GB, is doing just that. He has cut out a new support bracket to achieve that result. I have been thinking of doing the same but everything is going so well at the moment I don't like to touch it. I was able to balance my model laterally using battery placement.