MX650 mods? - Page 86 - Pocket Bike Forum - Mini Bikes
 4Likes
Reply
 
LinkBack Thread Tools
PBP RACER
 
Johnneh's Avatar
 
Join Date: Oct 2018
Age: 15
Posts: 173
Garage
Unfortunately I don't have any old computers lying around that I can take apart right now so I'll have to buy the fans online. But this is my next problem... where do put them?
Attached Images
File Type: jpg 20190629_161124_1561840001268.jpg (244.3 KB, 6 views)
File Type: jpg 20190629_161212_1561840034069.jpg (288.0 KB, 5 views)
File Type: jpg 20190629_161223_1561840051005.jpg (290.5 KB, 5 views)
File Type: jpg 20190629_161246_1561840104364.jpg (339.1 KB, 4 views)
Johnneh is offline  
Sponsored Links
Advertisement
 
Super Moderator
 
MrKitty's Avatar
 
Join Date: Mar 2014
Age: 38
Posts: 1,383
Garage
if you goto a computer shop they might have some fans for a few bucks difrent sizes as well keep in mind you want the bigest you can fit...

you just have to get out some zip ties and kind of play with it untill you find a spot

Faster then a speeding E Revo

Last edited by MrKitty; 06-29-2019 at 06:13 PM.
MrKitty is online now  
PBP RACER
 
Johnneh's Avatar
 
Join Date: Oct 2018
Age: 15
Posts: 173
Garage
Are you sure it's going to work though? How are 2 computer fans going to cool off my burning hot motor? Is there anyone else that tried this?
Johnneh is offline  
Sponsored Links
Advertisement
 
Super Moderator
 
MrKitty's Avatar
 
Join Date: Mar 2014
Age: 38
Posts: 1,383
Garage
there is no way to solve the problem completely but fans will help they will also dramatically cut down on your cool down time if you cant tuch the motor with your finger longer then 2 seconds its time for a cool down or risk both the motor and speed control going up in smoke...

Faster then a speeding E Revo
MrKitty is online now  
PBP RACER
 
Johnneh's Avatar
 
Join Date: Oct 2018
Age: 15
Posts: 173
Garage
Unfortunately I have been looking in tons of local computer stores for the past couple days and I haven't found any fans. I'm just going to buy 3 80mm 3,000 rpm fans on eBay. But how will I be able to turn the fans off and on? Will they turn off and on with the key, or will I have to buy a switch? And will I need multiple switches for each fan or will only need one?
Johnneh is offline  
verified
 
Join Date: Jun 2019
Posts: 1
Re: MX650 mods?

Hi. I just built a 4KW MX650. I found a good, cheap street tire for the rear but can't find a good cheap one for the front. The front is 16x2.4. I figure I need a 16" tire but how far can I deviate from the 2.4 part? I'll post pics in a bit. It's pretty insane. Thanks for any info!
Jesse Maloney is offline  
Super Moderator
 
MrKitty's Avatar
 
Join Date: Mar 2014
Age: 38
Posts: 1,383
Garage
I guess you don't have computer stores like the ones we have over here
20190710_131719_1562793794448.jpg

Faster then a speeding E Revo
MrKitty is online now  
PBP RACER
 
Johnneh's Avatar
 
Join Date: Oct 2018
Age: 15
Posts: 173
Garage
Ok so I installed 2 of the fans (for some reason one of them hasn't arrived yet..) but if the fans are all pulling from one battery, won't that battery be draining more than the rest and not ever get fully charged? I'll send pictures and explain what I did tomorrow.
Johnneh is offline  
Super Moderator
 
MrKitty's Avatar
 
Join Date: Mar 2014
Age: 38
Posts: 1,383
Garage
They take such a minuscule amount of energy to run that it doesn't even matter...

Faster then a speeding E Revo
MrKitty is online now  
PBP RACER
 
Johnneh's Avatar
 
Join Date: Oct 2018
Age: 15
Posts: 173
Garage
Well I bought this charger just in case

LST 12V Battery Trickle Charger Maintainer Portable Smart Float Charger for Car Motorcycle Lawn Mower SLA AGM GEL CELL WET Lead Acid Batteries https://www.amazon.com/dp/B07CZ7KWP3..._tDukDbHYAG938
Attached Images
File Type: jpg Screenshot_20190712-225217_Amazon Shopping_1562986380023.jpg (98.5 KB, 2 views)

Last edited by Johnneh; 4 Weeks Ago at 09:58 PM.
Johnneh is offline  
verified
 
Join Date: Aug 2019
Posts: 6
Re: MX650 mods?

Hi, I'm a new member and it wouldn't let me start a new post. I've read several pages on this thread and would like to modify 8 year old daughter's MX350 for a little more speed and more importantly more torque. I'm pretty familiar with the basics of electronics and have been involved in RC for 35 years. I've already bumped to 36 volt, all 3 batteries are 12 amps/each. Rest of the bike is stock, it's an early version with the rear shock also.

Speed on my phone app showed 21.4 mph and the wattmeter I hooked up (while she was riding) showed around 830 watts. I'd like to go brushless but there are many options out there. In the RC world, electric brushless power has taken over, brushed motors are nonexistent and gas/nitro motors have been surpassed as well. You simply can't beat the ease of use and performance of brushless motors and lipo technology. For my daughter's bike I'd like to stick with either SLA's or maybe a lithium Ion pack as Lipos require too much monitoring.

Ideally I'd like to shoot for a max of 25 mph with (strong) acceleration. Nothing that will flip her backwards but maybe pull a small wheelie on hard acceleration. (she weighs 60 lbs) I know dropping a few teeth on the front sprocket will help a ton, I've done this on sport bikes years ago and it makes a huge difference. I think stock is 11, may drop to a 9 tooth if possible. Big question is what brushless motor/esc/throttle to go with? I'm guessing I need to step up to 48 volts, that won't be a problem as there's plenty of room. Would something like this be too much or do I need to drop down to around a 1000 watt motor? Will probably have more questions, thanks for the help and sorry for the long post! https://www.ebay.com/itm/152886550579?ul_noapp=true

Last edited by jason999; 3 Days Ago at 08:46 AM.
jason999 is offline  
Super Moderator
 
MrKitty's Avatar
 
Join Date: Mar 2014
Age: 38
Posts: 1,383
Garage
sounds like something is wrong its a 350 watt motor it should have the clicker speed control the one with relays for low med high...

1800watts is way to mutch your going to be better off finding a MX650 and swaping everything over it will easily carry her to 30+ MPH...

Faster then a speeding E Revo
MrKitty is online now  
verified
 
Join Date: Aug 2019
Posts: 6
Re: MX650 mods?

Quote:
Originally Posted by MrKitty View Post
sounds like something is wrong its a 350 watt motor it should have the clicker speed control the one with relays for low med high...

1800watts is way to mutch your going to be better off finding a MX650 and swaping everything over it will easily carry her to 30+ MPH...
She's not very tall so I've thought sticking with the MX350 might offer some more confidence for her in that she can comfortably put her feet on the ground. How many watt motor would you shoot for? I don't want her going 30, 25 mph max, but I do want it to have a lot more torque. Is there a specific motor/esc combination that you would recommend? (ie: good quality/reliability)

Also, I think I've read the stock ESC really limits the max voltage when you over volt, have you head this? Would simply upgrading the ESC and throttle give us a boost in torque with the stock motor? Thanks again.
jason999 is offline  
Super Moderator
 
MrKitty's Avatar
 
Join Date: Mar 2014
Age: 38
Posts: 1,383
Garage
i whould get a mx650 and just swap everything onto the mx350 then build the 650 with a 1000watt brushless motor for when she gets bigger and you can ride it around camping and events until that day comes...

if you have the mx350 with the 3 speed clicker ESC there is no restiance

your into RC so you can see all the conecters and wiring is trash and should be upgraded you can do it with a wallmart amp wireing kit use EC5 plugs for the batterys then you can unplug them and charg them individualey to rebalance the bank i just hack off the motors wires and conectors short and hard solder them with amp wire and heat shrink...

1800watts will flip you on your back so quick its not even funny your going to want a extended swingarm...
Attached Images
File Type: jpg 1565656284631-2080781948_1565656345295.jpg (229.5 KB, 5 views)

Faster then a speeding E Revo

Last edited by MrKitty; 2 Days Ago at 07:46 PM.
MrKitty is online now  
verified
 
Join Date: Jan 2019
Posts: 14
That motor seems cheap, I paid a little over 200$ for a 2000w. I put it on my mx650 and it goes almost 30 with me on it (220lbs) with 4 lead acid batteries. I really think the lead acid batteries don't put out enough amps to power the motor to it's full extent. Voltage drops when I give it 1/2 throttle. With someone weighing 60lbs and a lipo I bet it be be pretty impressive.

If you find a reasonable price a 48v lipo that can handle amp draw from a 2000w motor let me know.


Quote:
Originally Posted by jason999 View Post
Hi, I'm a new member and it wouldn't let me start a new post. I've read several pages on this thread and would like to modify 8 year old daughter's MX350 for a little more speed and more importantly more torque. I'm pretty familiar with the basics of electronics and have been involved in RC for 35 years. I've already bumped to 36 volt, all 3 batteries are 12 amps/each. Rest of the bike is stock, it's an early version with the rear shock also.

Speed on my phone app showed 21.4 mph and the wattmeter I hooked up (while she was riding) showed around 830 watts. I'd like to go brushless but there are many options out there. In the RC world, electric brushless power has taken over, brushed motors are nonexistent and gas/nitro motors have been surpassed as well. You simply can't beat the ease of use and performance of brushless motors and lipo technology. For my daughter's bike I'd like to stick with either SLA's or maybe a lithium Ion pack as Lipos require too much monitoring.

Ideally I'd like to shoot for a max of 25 mph with (strong) acceleration. Nothing that will flip her backwards but maybe pull a small wheelie on hard acceleration. (she weighs 60 lbs) I know dropping a few teeth on the front sprocket will help a ton, I've done this on sport bikes years ago and it makes a huge difference. I think stock is 11, may drop to a 9 tooth if possible. Big question is what brushless motor/esc/throttle to go with? I'm guessing I need to step up to 48 volts, that won't be a problem as there's plenty of room. Would something like this be too much or do I need to drop down to around a 1000 watt motor? Will probably have more questions, thanks for the help and sorry for the long post! https://www.ebay.com/itm/152886550579?ul_noapp=true
sniper695 is offline  
Super Moderator
 
MrKitty's Avatar
 
Join Date: Mar 2014
Age: 38
Posts: 1,383
Garage
amps x volts = watts

those lead acid batterys onley provide about 8 amps eatch before the terminals start melting down

2000 48 = 41 or about 45 amps so your over by about 10 amps total and thats befor you factor in the loss in heat from the speed control wires and conectors you also have to factor in losses in the electronics...

Faster then a speeding E Revo

Last edited by MrKitty; 2 Days Ago at 11:54 AM.
MrKitty is online now  
verified
 
Join Date: Jan 2019
Posts: 14
Is there anyway to make up some of that amp under output without starting over? Your math makes sense.

Quote:
Originally Posted by MrKitty View Post
amps x volts = watts

those lead acid batterys onley provide about 8 amps eatch before the terminals start melting down

2000 48 = 41 or about 45 amps so your over by about 10 amps total and thats befor you factor in the loss in heat from the speed control wires and conectors you also have to factor in losses in the electronics...
sniper695 is offline  
Super Moderator
 
MrKitty's Avatar
 
Join Date: Mar 2014
Age: 38
Posts: 1,383
Garage
There are two things that are really cheap that you can do to help the situation...

Get one of those cheap $20 amplifier wiring kits for Mobile Audio from Walmart and use it to rewire the battery bank cut the wire off going into the ESC somewhat short and install EC5 plugs for RC cars.
Then cut off the wire going into the motor and coming out of the speed control somewhat short and hard solder the motor to the ESC using some of the amp wire. ( you can wrap black electrical tape around the red wire to make it a negative to avoid any confusion)

Go one or two teeth smaller on the motor sprocket people think that this will make you go slower but it's actually the exact opposite this will allow the motor to spin up to a higher RPM with less load on it giving you more torque a higher top speed less amp draw cooler running motor and ESC and longer run time...

Faster then a speeding E Revo
MrKitty is online now  
verified
 
Join Date: Aug 2019
Posts: 6
Re: MX650 mods?

Quote:
Originally Posted by MrKitty View Post
i whould get a mx650 and just swap everything onto the mx350 then build the 650 with a 1000watt brushless motor for when she gets bigger and you can ride it around camping and events until that day comes...

if you have the mx350 with the 3 speed clicker ESC there is no restiance

your into RC so you can see all the conecters and wiring is trash and should be upgraded you can do it with a wallmart amp wireing kit use EC5 plugs for the batterys then you can unplug them and charg them individualey to rebalance the bank i just hack off the motors wires and conectors short and hard solder them with amp wire and heat shrink...

1800watts will flip you on your back so quick its not even funny your going to want a extended swingarm...
Some great advice, thanks! How about picking up a MX500, I think they sit a couple inches lower. Great advice on adding connectors (I like Dean's connectors) to each battery to charge individually every so often. (for balancing purposes) I'd still like to use the 36 volt charger for easy charging, how often would you charge individually? Every 10-20 charges for example?

So 1800 watt motor is a no go, maybe I'll stick with a 1000 watt and 48 volt. Definitely going to drop a couple teeth on the front sprocket, do you know off the top of your head where do get a smaller sprocket for the stock 350 motor? May experiment with the gearing before going brushless. Thanks for the advice, great forum!
jason999 is offline  
verified
 
Join Date: Aug 2019
Posts: 6
Re: MX650 mods?

Quote:
Originally Posted by sniper695 View Post
That motor seems cheap, I paid a little over 200$ for a 2000w. I put it on my mx650 and it goes almost 30 with me on it (220lbs) with 4 lead acid batteries. I really think the lead acid batteries don't put out enough amps to power the motor to it's full extent. Voltage drops when I give it 1/2 throttle. With someone weighing 60lbs and a lipo I bet it be be pretty impressive.

If you find a reasonable price a 48v lipo that can handle amp draw from a 2000w motor let me know.
Lipos can handle an impressive amount. You'd need to find a couple 6 cell (6S is how they are designated for 6 cell) and run them in series, would give you over 48 volt. Hobbyking.com typically has the best prices, look for a high "C" rating also, 30C or better. Also, choose a US warehouse location or it will take a month to receive from China. We run 12S regularly in RC helicopters and a local guy was getting 12,000 watts output on his setup! It's common to run 120 and 160 amp ESC's on the bigger RC helicopters also. They are rated for 50 volts.

Also, you'll want a good charging system to charge these big lipos. Typically an iCharger that charges at 30 amps is good plus you'll need a power supply, guys usually make these from computer power supplies and put them in a case. (I had a guy locally make mine for about $150) I can charge (4) 6S 5 amp batteries in about 20 minutes via parallel charging.
jason999 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Pocket Bike Forum - Mini Bikes forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in













Posting Rules  
You may not post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome