Ok I would like some more mph..mxus help

[Mudduck]

Ok I got help mxus kit from cellman is there any way I can get some more mph out of it?the battery Paul made me is a 36v 6.9 ahr battery that reads full led battery power when I get home from a 14 mile round trip from work..I gt about 17-18 mph now Im looking for another 4-6 mph?Maybe a controller upgrade,save up a get the Mac?anything?thanks

[Racer_X]

Mudduck , We need more details. Are you talking about the MXUS Direct Drive motor? What controller did you get with that?
You say your battery is a 36v 6.9 ah, Either this is a custom battery OR you are giving us wrong information.
if it is a 36v 6.9 ahr battery. What is the dimensions and weight?

[wesnewell]

Series in a 4s lipo pack. Set lvc up higher or monitor voltage.

[Mudduck]

Sorry I got the rear geared hub motor..Paul called the battery a 39volt 6.9 amp hour battery..3"thick 5" height 10" length.17 amp controller..

[dogman]

A few more mph is possible with 48v. But real speed is going to take bigger, heavier direct drive motors and much higher voltage.
If you want to stick with gearmotors, then the faster winding mac motor has more power and speed. 48v can get you 30 mph.

[Mudduck]

So upgrading the controller out..more volts would help.how about the Mac 8t geared motor on my battery?

[Racer_X]

If you want speed on your battery get the 6T motor. That is the highest RPM MAC motor cellman carries. Should be able to hit 30+ from what i read here on the sphere.

[Mudduck]

Yes but is my battery good enough?

[Joseph C.]

Yes but is my battery good enough?

Your battery has 269 watt-hours. It is rated for 30c but cell_man recommends ten C.

Yes, is the short answer. You will get about 24 MPH from an eight turn MAC from that battery.

Edit: With the eight turn MAC and nine FET controller your bike will rarely see over five C.

[neptronix]

Yes but is my battery good enough?

On a 6T, it will sag pretty badly even though it is a fairly high output one. It won't last as long as it could, IMHO. The 6T is super amp hungry and will do over 30mph on that voltage.

8T would be a bit more reasonable, it would do a little over 25mph on a 26" wheel. Efficiency and amp draw at a lower speed is much better.

[dogman]

Well, there is the rub, the battery. Good battery, and perhaps perfect for your current setup.

But more speed takes unbelivably more power. Sag will be an issue, but not nearly as big an issue as simply running out way too much quicker. Right now, your 20 mph top speed takes 350-450 watts with no pedaling. 25 mph will be taking closer to 700, and 30 can take as much as 1000, depending on grades or wind.

You can quickly go from a 45 min battery to a 15 min battery. Very likely you would have to at least buy another similar size battery to have enough wh to be of much use with a more powerful motor.

Then there is the issue of the voltage. To get the most speed out of a mac, you really need 48v. So it's really a do over to get a lot more performance.

Perhaps the best thing would be to try your current motor at 48v. you will get 3-4 more mph, and a few more watts. The battery could be anything from a lead battery to some small a123 packs from ebay. If the test works out to your liking, buy another cellman battery in 48v, and use the old 36v one as a range extender when you want a longer ride. A less costly alternative would be to buy a bms and some cells from cellman, and convert your battery to 48v.

[Mudduck]

Now I know why just about everyone has built several bikes...I'm very happy with the kit I got,but just like everyone else us ebikers are never happy, always looking for more speed...well I think I'll email cellman and work something out maybe new bike who knows...

[neptronix]

You had the same experience as i. I ordered the 250w MXUS motor KIT and some RC lipos early on. That was cool for about a month, then i ordered the MAC motor. It's been a love affair ever since. Guarantee you won't be disappointed by it.

The 8 turn will work OK with your current battery, but like dogman said, your mileage will go waaaay down due to the higher speed. Damn aerodynamics... !

Still like my 8 turn even to this day. A 3 speed switch set to 21-22mph helps me get closer to the great efficiency that the 250w motor had.

I've had motor/battery setups that did 18, 20, 25, 32, 42, 46mph top speeds.. And i gotta say.. 20-25mph is about as fast as you want to go if you are interested in pedaling and the bike still being a bike!

[Mudduck]

Thanks neptronix I'm glad I'm not alone....I'm going to email Paul ..not sure if I want a new bike..but ether way I going to order the 8 t Mac.at least this time I'm not in a hurry, ship it the slow boat from china..

[neptronix]

I you can wait 2-3 months, slow boat is OK.
No shipping updates for that long can be agonizing though.

SAL is a great deal for how fast it is.

[Mudduck]

Yea that's what I just did the sal was fast..about 2 weeks..but double the price.

[Anamelesssomebody]

if you upgrade, what are you going to do with the old stuff?








Edited to get the arrows right --------------------------------------------------------------------------------->>>>>>>>>>>>>>>>>>>

[Mudduck]

That is the question?i see you live near me.what would you want just the wheel kit,or the the whole thing?Im going to email Paul to see what he says about my battery running a Mac.

[cell_man]

A 3P pack would be ok on an 8T Mac running a 30A 9 fet. You'll see a little sag under full load when it's cold, but nothing major and nothing to worry about. As others have said, speed takes power and range at 25mph is way less than range on same battery at 20mph. There is a neat way you can feed a second battery into the primary battery into the charger plug. If you wanted to add a second pack later for more range, you could connect it in that way when you need that extra range, or just take 1 pack when you don't need the range. This is a better solution than running packs in parallel and that second battery could be the same parallel count,it could be smaller or it could be bigger.

You'll see about 25mph or very close to it on the 12S pack with an 8T Mac in 26", it's fast enough and in my opinion once you start going much faster than that, the battery requirements for any sort of range escalate very quickly. The 3 speed switch also means you can keep your speed in check when you do need to stretch out the pack and if you also get a program cable, you can adjust current level if you wish. You can even re-program speed 3 on the controller to 120% and get speeds of 15-20% higher, so you might even get close to 30mph on that 8T still on only about 36V. I've seen high 30s MPH on an 8T on 48V with 120% speed setting for example, a touch over 30mph on standard 100% speed.

Another and also cheaper option is to use a 6 fet Infineon and apply the same 120% speed setting to the MXUS for higher top speed, but the MXUS is not a power monster, so you would need to keep a check on the motor and go a bit gentle to avoid overheating or damaged gears. I don't see why you wouldn't see a similar 15-20% increase in max speed on the MXUS, the result should be close to what you might get running the motor on 48V.

Apologies if I have now made too many options for you there, sometimes too many is as bad as not enough SAL is double the price, but takes about a quarter the time as surface does, so by my calcs, it's half the price I think

[Anamelesssomebody]

That was some good explaining by cell man. It gives you a lot of options. Since he thinks your battery will work a few different ways, I guess just the wheel kit if you go the Mac route. I'm in galloway.

[boppinbob]

Mudduck, I too, have a slow, safe bike. It is legal and I use it as a commuter bike to work (500w rear hub dd motor, 36v12ah batt phantom x) It uses lifepo4. It is governed to 20 mph max. I am not going to modify it. It fits my commuter needs well. I built another bike that is much faster. (HS 3540, 72v 50a with lipo ) I use it as my thrill seeker bike. I don't use it to go to work because it's not street legal strictly speaking, and because of the infinitesimally small chance of spontaneous combustion of the lipo pack which would suck if it happened on company property. You are right, the people in this forum usually have more than one or two bikes and ride the one which suits their needs the best. If it were me, I'd do another build that exactly fits my needs, and give the first bike to your wife or girlfriend. (or boyfriend if that's how you roll)

[motomech]

Cell_man wrote

Another and also cheaper option is to use a 6 fet Infineon and apply the same 120% speed setting to the MXUS for higher top speed, but the MXUS is not a power monster, so you would need to keep a check on the motor and go a bit gentle to avoid overheating or damaged gears. I don't see why you wouldn't see a similar 15-20% increase in max speed on the MXUS, the result should be close to what you might get running the motor on 48V.

Paul, have you tried this?
I've read here, at least one rider, who tried that w/ a geared mini-motor[can't remember which one] and the result was no speed gain.
Sorry, I can't say what the reason was[he had a theory]or link it right now, it was while ago.

Mudduck-You could add another MXUS on the frt., gain maybe 2 mph and have a much better climber. All for little cost in W/hr.s.

Paul's friend, Chinaphil, did it a while back.

viewtopic.php?t=24866

[neptronix]

If you added another motor, you'd have 12-14lbs worth of motor.
The total cost of both motors would be over a MAC motor.
The MAC motor only weighs 10lbs. and is more powerful than 2 MXUS motors combined

I've ran mine at 35-39mph constant for long periods of time.

It's likely that there will be no speed gain. More torque, yes. More speed? probably not.

So, bad idea

[Mudduck]

Thanks,Paul!this is why I'm happy I found you thru this fourm..yes the sal shipping is twice the price but your right,but well worth it.I'm very happy I did it..I've done about 48miles since I got it..I think my best bet is to go with the Mac.at least that way I can upgrade..because once I hit 25 mph I'm sure I'd want to go faster..really want to think about it..I just love riding my bike to work now...I haven't started my suv in a week..

[motomech]

If you added another motor, you'd have 12-14lbs worth of motor.
The total cost of both motors would be over a MAC motor.
The MAC motor only weighs 10lbs. and is more powerful than 2 MXUS motors combined

I've ran mine at 35-39mph constant for long periods of time.

It's likely that there will be no speed gain. More torque, yes. More speed? probably not.

So, bad idea

Well, not that bad of an idea, but it seems like at this point, Mudduck is committed to best speed with his existing pak. And that clearly means the 8T MAC.
Still,

If you added another motor, you'd have 12-14lbs worth of motor.

Yeah, but it is distributed between 2 wheels with half the unsprung weight.

The total cost of both motors would be over a MAC motor.

Only if he was starting from scratch. But he already has the MXUS kit and if he can't use it for this build or another, it's worth what he can resale it for. I think it would resale easy enough, but he is still is going to take a hit.[Mudduck, I'll give you $200 for it, you ship to Md.]. Actually, the difference in $ is not really enough to be much of a consideration

The MAC motor only weighs 10lbs. and is more powerful than 2 MXUS motors combined

Not at 39V and using the stock controllers.
2 MXUS controllers....... @ 17A-34A-1326 Watts
Cell_man kit supplied controller 30A-1170 Watts
Sure there would be some parasitic losses associated with two operating systems, but they are small..
And the Mac would be easier to pump up, but that add costs, something that Mudduck is not wanting to consider at this time.

It's likely that there will be no speed gain. More torque, yes. More speed? probably not.

I must stand my ground on this one Every report that I have seen[here and at Pedelec UK] states a 1 to 2 mph gain when combining two like motors.
My interest is mini-motors, so Graykard and Chinaphil come to mind. Actually. The Ebike sim. shows why this is so[and the sim. never lies...it's just misinterpetreted ]. Take any pair of motors and the sum of the two motors will move the "load-line" up approx. 2 mph.

But for Mudduck, who probably isn't interested in tinkering with a 2WD build, or in general, for street only use, the MAC's ability to hit the target speed of 25 mph on 39V and retain some climbing prowless, is truely impressive.

Finally, Pauls' comments about the battery leads me to think that it would be easier to add capacity than voltage, makes the MAC the best choice imo.

Mudducks very last comments about even more speed indicate that "the bug has bitten" and makes me wonder if he could afford to add that extra battery capacity and wasn't facing any tough hills, could he even go with a 6T?