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[Big Ada]

Listening to the motor in my Club 500 it sounds faster in reverse, is there a simple way I can swap things around so that its faster forwards, changing the hand of the prop?
Regards,
Len.

[kmmbcwebmaster]

Just swap your wires from your motor to speed controller around 

[Netleyned]

Just swap your wires from your motor to speed controller around 

?????

Ned

[knoby]

You need to do both, swap the wires & change the prop hand.

[Netleyned]

You need to do both, swap the wires & change the prop hand.

 

Ned

[red181]

if you are racing as per club 500 rules, you cant swop the hand of the prop, its not allowed, however if just playing around, then what esc are you using? if its an mtroniks then check you have full forward throttle you can see the green led lit if it is. Try resetting you tx to ensure you have full forward, and use the trim tab to just "creep" a bit more forward rpm.
 
Was the motor new? has it always run the same direction? , if so the brushes should be bedded in to give more rpm forward, it may sound faster in reverse, but infact may be slower as the driveline might just be quiter going forward rather than in reverse. My club 500 sound way faster in reverse, but using a cheap tacho meter it is actually turning faster in fwd.
 
A good test is connect motor direct to a battery thus eliminating tx and esc settings, then try it the other way around, with shaft disconnected, then you have no other things that could be distorting the conclusion

[malcolmfrary]

Could just be a bit of end play in the prop shaft making it sound different in reverse.

[Big Ada]

Thanks for all your input guys, now totally confuddled.
 
len.

[mikegunn]

Hi all
I am really a complete newbie to boats but have been into rc and electricals for many years. Please feel free to shoot this down if wrong but I seem to recall reading that all brushed motors run faster in one direction than the other due to the motor's timing angle. I believe this to be the relationship between the relative angles of brushes, armature segments and the motor's permnanemt magnet array. If the brushes are held in a removeable end bell then a very small rotation of this can have a dramatic effect on motor output (and current draw). I have never tried messing with this as I use brushless in my rc planes and I'm also unsure if the rules for this class of racing would allow it, but just some food for thought really.
now for the 7th time the answer is titanic.....lol
cheers Mike

[red181]

Hi Mike, yes if the boat is running within club 500 rules, no modifications are allowed to standard motor, or anything below water line, so removing the can, and fiddling timing would be illegal, however, big ada has not confirmed if boat is being run in the spirit of the rules yet, so we cant really advise further, 

[essex2visuvesi]

Hi all
I am really a complete newbie to boats but have been into rc and electricals for many years. Please feel free to shoot this down if wrong but I seem to recall reading that all brushed motors run faster in one direction than the other due to the motor's timing angle. I believe this to be the relationship between the relative angles of brushes, armature segments and the motor's permnanemt magnet array. If the brushes are held in a removeable end bell then a very small rotation of this can have a dramatic effect on motor output (and current draw). I have never tried messing with this as I use brushless in my rc planes and I'm also unsure if the rules for this class of racing would allow it, but just some food for thought really.
now for the 7th time the answer is titanic.....lol
cheers Mike

It used to be called "Cranking" in the RC car world back in the mid 80's and was frowned upon in the standard race classes.  Rumor was that you could crank a standard 540 with an allen key an old pinion and a pair of pliers.  Never tried it myself tho


Some higher end race motors (also called modified) had adjustable timing which did exactly as you say

If you look on the can above the A and R you can see the timing marks

[Big Ada]

We are racing 500s but no too seriously, one boat is faster than all the others but looks internally the same as ours.
 
Len.

[mikegunn]

Hi Len
The picture provided by essex2 is exactly what I was thinking of. Might be worth a little tweak if you can loosen the end bell a little. My recollection of the cheap mabuchi type motors was that the end bell was held in place by a couple of 'bend over' tabs extending from the can, and these engaged in slots in the end bell itself. These tabs not only held the end bell in place but stopped it rotating as well. Widen the slots a bit to allow some rotation of the end bell and then a couple of spots of epoxy to stop further rotation once you have found the 'sweet spot' . Once again this is offered as 'ideas only' as I  have not tried myself.
Your friend may have just been lucky with the build of his motor as I'm assuming these are quite cheap and therefore quality control may not be that good in the assembly process?
cheers...mike

[grasshopper]

The whole 'art' of tweaking electric motors like the 540 has been documented and can probably be found on the Internet somewhere...but basically,


Bedding in the brushes when new gave performance advantages - used to be done by either a long run in period with just enough voltage to turn it over, clean out and then install in model. Alternatively, a high speed dunk into a water bath which softened the brushes and helped seat them better on the comm' , dry out, re-lube and install. (Legal mod)


Advancing the timing of the motor by as much as 45 degrees could be done to give a little extra RPM in one direction only by rotating the endbell, lift the tags carefully and rotate the end plate and listen to the change in speed - better if you have a tach' and an ammeter connected to check results. (Illegal mod!


Re-wiring the armature is also possible, reducing the number of turns, increasing the thickness of the wire or both alters performance also.  It was once said that one of the coils in Mabuchi motors was wired in the opposite direction to the other two due to the way the production machine worked, removing the wire and reversing the direction of wind made motors a lot more efficient and wasn't classed as a modification. Bit like the lost art of 'blue printing' was for real engines.


What did the article say in one of the early model boat mags, Mabuchi produced millions of motors per day world wide, there will be some better than others.

[red181]

slightly away from the question Len, but we race club 500's, weight and batteries plays a massive part, I use a micro servo for rudder, and some thin clear plastic for the hull top, and  a few other weight loss tricks. My battery is legal 7.4v, but a good make, overlander, I also top up the battery just before a race, I get another 500 or so mah into it, and always come out of the blocks as one of the fastest. Motor is legal, I use an oiler on the shaft, and lube the motor bearings before every race. Shaft alignment is crucial, I used a solid coupling to get it right, and my prop blades are no more than 1 mm from the hull, it all makes a difference, it might not just be the motor, if someone has tampered with the motor just for club 500 then they need to have a word with themselves   cheating in club 500 must the the lowest you can get!!

[knoby]

Have to agree with RED, reducing weight & friction is about all you can do to improve club 500 speed, but there are many things you can do to slow one down, over packing the propshaft with grease seems to be a common fault. The area where you can gain most speed is by improving the interface between boat & transmitter, better known as the driver, missing the marks by 25 feet & zig zagging between them isnt the quickest route, but often the most popular.

[red181]

spot on knoby about the driver   I am far too stick heavy, so reduced the throw of the rudder servo, as club 500 never needs to make a tight turn, it help greatly, drive it like a go-kart with centrifugal clutch, dont scrub speed off with tight turns, in wide, out tight, providing you are not having to be defensive, and make the boat "wide" if being passed, force your opponents off the racing line, and create dirty water! all legal!!
 
Use velco to attach the battery tray, in choppy water move it forward to minimise porpoising with more front end weight, calm dead water move it backwards to the rear and get the prop in the water and bow up on the plane, tricks of the trade

[knoby]

This is my first year of 500 racing, but I have raced all sorts of fast electrics in the past. unfortunately I can no longer afford to go at the speed I like going. so I thought I would try 500's & I have to say its such great fun. Still learning how to get the best from them, but its coming along nicely so far.

[Big Ada]

Thanks guys, I am taking all this in.
I will be racing on Sunday weather permitting, its blowing a hoolie at the moment.
 
Len.