Brushless Mountain Bike w/ 80-100-B 130Kv

Hi everyone,

I have read a few threads here and you guys are great! Lots of nice projects too!

It's just a quick and dirty build for now on 2 crappy lead acids, but this is just temporary till my Lipo's get here. I badly need to add a second stage to the drive train as it's like its' in 5th gear all the time right now. I have gotten it up to 34.7mph but that's with it drawing a steady 90+ amps! The little Power Wheels battery sizzles when I do that!

It cruses at ~15 mph at ~10 amps though, and I have made a few 10 mile round trips to my local bike shop like this so far.

I have a lot to do to get it to where I am really happy with it though, the #1 thing being the gearing. I would like to have the ability to use the bike's stock rear gears to their full advantage for low speed/high torque for off roading and high speed/low torque for high road speeds.

It's been fun so far. Thanks for the inspiration guys!

Here are some quick pics of my project in it's first stage.

Great to meet you all!

Later,
Jay

(hey, it clipped my pics :| )

Hi Jay and welcome.

Looks like a fun bike. You are right with your idea of getting the gearing lower. What ratio are you running to the crank?

Did you drill through the frame for your mount? This may affect the strength of your frame, particularly if you are going hammering downhill

I'm working on a similar set up how is that turnigy watt meter working as your throttle I looked at doing the same thing.

Grinhill said:

Hi Jay and welcome.

Looks like a fun bike. You are right with your idea of getting the gearing lower. What ratio are you running to the crank?

Did you drill through the frame for your mount? This may affect the strength of your frame, particularly if you are going hammering downhill

Click to expand...

Hi Grunhill,

Yeah, I drilled through my frame...I hope it will be OK! It's very oval tube and thicker than I thought it would be when I drilled through it. I put my money on the fact that it's got good suspension. I have yet to bottom it out even with these heavy LA's on it. The lipos will be much lighter and I plan on adding annother piece aluminum to the other side to support the jack shaft I will put above the shock/motor. Hope is the key word! I need to get a helmet!

I haven't done much tooth counting yet. The pinion is a 9t, and I have a 34t sprocket for the rear cassette on the way. I really need to sit down and get the counts. I will do that tomorrow.

I got some 8awg wire to re-wire the system as the 12awg wire it has now gets warm.

Also, I will be at 44.4 volts with the lipos so I need to fugure that into the equation too.

What do you think is the best way to do the jack shaft for the second stage?

Thanks,
Jay

dumbluck said:

I'm working on a similar set up how is that turnigy watt meter working as your throttle I looked at doing the same thing.

Click to expand...

Hi dumbluck,

The watt meter is working great! I did toutch up some of the soldering inside though. Looked like a few potentially cold solder joints when I first opened it up.

The thumb throttle itself could use some fine tuning though. So far I have had to adjust its' spring tension twice and add some masking tape to the pot case beteen it and its' mount, and to the pots' shaft to get rid of the "play" it had stock. For $30+ dollars I thought it'd be nice and quality, but it's not. I will make it to my liking one way or another though.

Got pics of your project?

Later,
Jay

Hi everyone,

My PC (hd) went down the day after I posted.

I got it all beck though with a new OS and HD, and was able to get my most important files off the old HD by mounting it as a slave.

Anyway, the lipos arived for 22.2v 10Ah, I rewired the bike with 8awg wire,and ran ribon cable to a dashboard display I made up and took her for a ride.

New top speed is 39.9Mph! Not bad for 22.2v and bad gearing, huh?

I burnt the ESC on an off road uphill trail though.

That's ok, Gives me a reason to get one with more over head and also change the gearing.

GTG, Im at work.

Later,
Jay

GITech said:

New top speed is 39.9Mph! Not bad for 22.2v and bad gearing, huh?

I burnt the ESC on an off road uphill trail though.

Click to expand...

That's amazing for such a simple build!!!

What type of ESC did you fry, and what sort will you get next?

Hi grunhill,

Hey, thanks!

I talk more about it here: http://www.endless-sphere.com/forums/viewtopic.php?f=9&t=11877&start=15

I am looking at the Hobbywing Platinum (?). It's 120A cont, 180A max and has firmware update-ability.I want to look into the "K-Force" ESC's as well if HC ever carries them again.

Later,
Jay

Hey I am new to this site and had to post my new bluid, the lawn mower powered mtb which is working great but theres room for improvement I did come up with good jack set up which is a challange for non hub motors Check my posts on genaral ebike discussions, go with 1/4 pitch chain on primary, the 1/4 pitch will save on realestate needed, use standard bike pitch for final. As for potentometer I used a simple spring loaded linear potentometer from p3 america, just type in to browers,I hope this helps. I would like to know more about the motor your are using

GITech said:

Hi everyone,

I have read a few threads here and you guys are great! Lots of nice projects too!

It's just a quick and dirty build for now on 2 crappy lead acids, but this is just temporary till my Lipo's get here. I badly need to add a second stage to the drive train as it's like its' in 5th gear all the time right now. I have gotten it up to 34.7mph but that's with it drawing a steady 90+ amps! The little Power Wheels battery sizzles when I do that!

It cruses at ~15 mph at ~10 amps though, and I have made a few 10 mile round trips to my local bike shop like this so far.

I have a lot to do to get it to where I am really happy with it though, the #1 thing being the gearing. I would like to have the ability to use the bike's stock rear gears to their full advantage for low speed/high torque for off roading and high speed/low torque for high road speeds.

It's been fun so far. Thanks for the inspiration guys!

Here are some quick pics of my project in it's first stage.

Great to meet you all!

Later,
Jay

(hey, it clipped my pics :| )

Click to expand...

Hi torqueon,

Nice to meet you. Sounds cool. I'd like to see it. Can you paste a link to your bike?

Here's the motor. The new version shown in the pic now is much nicer than 'my' old one. Read the reviews! http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=5142&Product_Name=Turnigy_80-100-B_130Kv_Brushless_Outrunner_(eq:_70-55)

Do I see a capacitor added to the esc? That looks good. I think a reason it fried is because of the way you mounted it. Heat rises, and when the esc is on it's side, the heat can't go directly up to the heatsink. Also, what were your temps? Around 160-175f is when an rc controller will get close to failing. 140 is about the limit to where you don't need to worry about it.

Metallover said:

Do I see a capacitor added to the esc? That looks good. I think a reason it fried is because of the way you mounted it. Heat rises, and when the esc is on it's side, the heat can't go directly up to the heatsink. Also, what were your temps? Around 160-175f is when an rc controller will get close to failing. 140 is about the limit to where you don't need to worry about it.

Click to expand...

Yes, it's a huge 8200uF 63WV cap. I have ~5 of them I got years ago just waiting for an application. I am not sure about the temps at all but it was super hot. It was smoking by the time I stopped, got off the bike and removed the power. :?

In your theory of heat transfer and dissipation related to the orientation of the ESC that you're thinking of is only true with "Convection" in a 'still air' environment. The type of heat transfer from the FETs to the heat sink is "Conduction". Conduction is heat transfer through a material as thermal energy moves from molecule to molecule through a substance or from one object to an adjoining object. The 'direction' of heat transfer through an object via Conduction is not governed by up, down, left, or right. While riding, the efficiency of airflow over the heatsink is now the issue. Forced air could have kept the temp lower as it blew out at a slow 15mph, going up hill. But, I'm not sure if any of this matters much in this case of my ESC burning as I was pulling over 110amps through this 100amp controller for several seconds before it blew.

I took some pics while I was rebuilding the system in 8AWG and running the display to a dash, getting ready for the Lipo's. So, as not to let them go to waste here are some pics of the ESC build before this fatal run. Later I will take some pics of the whole bike before I tear it down for another rebuild.

As I can only save ~30 bucks a week toward the bike I may be SOL for quite a long time. :|

I was thinking about submerging the ESC in a liquid such as mineral oil. Has anyone ever tried this...like they do with overclocked PC's?

Later,
Jay

Hi guys,

I just took pics of the bike as it was during the fatal run and just before I tore it down to evaluate the ESCs' internals.

The FET board only blew one FET but the VR's on the control board are blown as well. Strange?

I'm a surface mount solder and PCB QC, testing and repair technician so I may still be able to revive it. We'll see. Not much use in doing so though as I don't even want this old version anymore.

I removed all of the elec parts from the bike and put the peddles back on, that's the best I can do for now... :|

Well, here's the pics.

Later,
Jay

Do you think something shorted out? Seems like if you have a classic "esc fry" incident, most or all of the fets would be gone.

Yeah, it seems strange, I don't know. I didn't spend much time with it. I just soldered on a quick power plug and an old TP2409-18 motor after removing the one FET and checking for other shorts. No beeping, just smoke from the VR's.

Jay

Those ESC's never last with that motor. The hobbywing 120a is the same as the turnigy version 4, and the 140amp model of the turnigy version 4 is the same as the 100amp, but with the FET board fully populated (6 more wimpy FETs). They seemed to fail sooner than the 100amp versions, and I suspect it's because the FET drivers were switching the FETs too slowly with the under populated board.

If you want something reliable, it's best to fit sensors and run an e-bike controller. It's a lot of work, but you obviously seem like a guy who has some skills with the soldering iron. If you want a quick band-aid fix, the Castle Creations 140amp is about the best available at the moment.

-Luke

Thanks for the advice LFP.

At $339.00, the CC140HV is far from a 'quick fix' for me though.

Also, I have had 5 CC ESC's and 30+ "cheap chinese" ESC's. ALL of my CC ESC's died for "no reason", honestly. CC only replaced 2 out of the 5 of them for me. Both those fried too under normal use. I have no faith in CC, at all, any more, especially at the price they get for them. Nearly every cheap chinese ESC I have purchased is either still working years later, or burned out because of things like getting them wet or clearly overloading them. Sorry, that's just my experience. :wink:

BTW: I like you're name! Physics rules! :wink:

Jay

Castle should be coming out with a new HV controller. An Ice HV controller iirc. It should be much cheaper then the curent HV controller.. The 100a 8s capable Ice only costs $140.

GITech said:

Thanks for the advice LFP.

At $339.00, the CC140HV is far from a 'quick fix' for me though.

Also, I have had 5 CC ESC's and 30+ "cheap chinese" ESC's. ALL of my CC ESC's died for "no reason", honestly. CC only replaced 2 out of the 5 of them for me. Both those fried too under normal use. I have no faith in CC, at all, any more, especially at the price they get for them. Nearly every cheap chinese ESC I have purchased is either still working years later, or burned out because of things like getting them wet or clearly overloading them. Sorry, that's just my experience. :wink:

BTW: I like you're name! Physics rules! :wink:

Jay

Click to expand...

I do not mean to be rude, but, your controllers are NOT dying under "Normal" use. I have over 1000 miles on CC HV controllers used in numerous builds and I know what they need to survive. If they are blowing, you are misusing them, period.

I have confidence in CC controllers if used within their spec and properly supported with good cells and wiring. I have two HV140s giving me 18 HP in my trike with no problems. They do not even get warm.

I have also been using them in top speed RC cars for years. I regularly pull 127 amps out of an HV110 in my 100+mph RC car without any problems.

I am surprised Castle replaced any of them for you. 99% of the time a controller blows, it was from misuse, or (more likely) inadequately setup.

Before you bash a product, make sure you are using it properly.

Matt

GITech said:

... Yes, it's a huge 8200uF 63WV cap. I have ~5 of them I got years ago just waiting for an application. I am not sure about the temps at all but it was super hot. It was smoking by the time I stopped, got off the bike and removed the power. :? ...

Click to expand...

It must be a low ESR type cap.
What is the wire length between battery and controller? Maybe you need more capacitance.

Better to use several smaller caps instead of one biggie. Smaller caps can shed more heat and total inductance will be lower (inductance per cap is lower and those inductances are paralled to boot ). See pictures in first post:
http://www.rcgroups.com/forums/showthread.php?t=952523

Vriendelijke groeten Ron
• brushless motor building tips & tricks • diy brushless motor discussion •
• Drive Calculator discussion • int. electric fly-in, Nijmegen/Netherlands •

Thank you for the advice ron van sommeren. I will do something similar for my next build!

recompence, woahhh there, it was you that got me interested in starting this project last year. You're awesome IMO. What's up with calling me a liar and insulting my inteligence? :|

I'm on lunch. GTG.

Later,
Jay

Now you are calling me a liar. I NEVER called you a liar. What I said was, controllers blow from misuse, not from normal use.

It is one thing to have one contorller die for no reason. If it is happening repeatedly, it is an end user problem.

The issue I take is bashing a manufacturer who has a very good track record and who is willing to work with us on E-bike stuff. Most RC manufacturers will not even sell to you if they know you are running an E-bike.

I am not mad at you, nor did I call you a liar. I just want people to understand CC controllers are fine if properly used.

Matt

Thank you. I got your PM but I can't reply tonight. This is my friday.

Take care amd TTYL,
Jay

recumpence said:

I just want people to understand CC controllers are fine if properly used.

Matt

Click to expand...

That's been my limited experience so far with CC controllers (Still have the original!). Although, for some reason, something in my electrical system was bugging out on me for a moment - it was like one phase wasn't getting current or not enough current and that caused the motor to "stutter". After relaxing a bit, it didn't happen again except for a brief sputter. :/ I was going faster than 5 mph, so I didn't think it was losing synchronization but that might have been it for some reason.

It seems one motor wire was half-cut and it might be pulling itself apart, so maybe that had something to do with it? But it was still electrically attached...

It is possible that one wire was not always making contact. I had that problem with my trike the other day. It makes the motor stutter a bit.

Matt