Andrew's LMX 161 Chain-drive massacre Build Log

BCTECH said:
what kind of circuit breaker did you use?

Hi mate, I bought this one... https://www.ebay.co.uk/itm/63A-DC-C...495247&hash=item3f53e959ec:g:URUAAOSw3YNXYTfc

Not sure if it will be the correct ampage. I have an AC version , same amp rating, on my nyx bike and it have never tripped with around around 100amp peaks.

The lmx is pretty much finished, i just need to spend some time tuning the kelly controller and taking it for some test rides before a proper shake down in the woods. Ive had a busy and testing couple of weeks at home and in work so i am a bit out of rhythm with the bikes at present. I will try and make another video clip soon with some shots of the finished bike. I must say, at present the chain is fiercely loud
 
thanks for all the info , much appreciated, ill follow some of your examples , the circuit breaker pre charge resistor are good ideas for protection.

the chain should not be loud as the #400s, is your motor well configured not shaking or making noise? why is the chain loud? i find the #219 very silent , you must have something somewhere i think
 
maitilupas said:
thanks for all the info , much appreciated, ill follow some of your examples , the circuit breaker pre charge resistor are good ideas for protection.

the chain should not be loud as the #400s, is your motor well configured not shaking or making noise? why is the chain loud? i find the #219 very silent , you must have something somewhere i think

Its not the chain itself, it is the chain rubbing on the plastic guard (the guard sits on the top of the swingarm pivot point, near the foot pegs. I wonder of there is something softer and more disposable i can put on it?
244qet0.jpg
 
i use a wheel bearing after the pivot, but im with lmx 2.1
have a look/:
 

Attachments

  • IMG_3741.jpg
    IMG_3741.jpg
    402.6 KB · Views: 2,477
Actually, from closer inspection, its not the plastic guard and chain making the noise, it is the small motor sprocket that is making all the racket. However, i have only teste the bike without load with rear wheel off the ground.
Is it normal for the front sprocket and motor to be noisy?

[youtube]wA6SmJwbRgo[/youtube]
 
thanks for the video , the sprocket and motor produce some noise, but i think it is sounding a bit louder than mine , maybe the aluminium parts are amplifying a certain frequency or something , maybe Adam can input what he thinks of
 
brumbrum said:
BCTECH said:
what kind of circuit breaker did you use?

Hi mate, I bought this one... https://www.ebay.co.uk/itm/63A-DC-C...495247&hash=item3f53e959ec:g:URUAAOSw3YNXYTfc

Not sure if it will be the correct ampage. I have an AC version , same amp rating, on my nyx bike and it have never tripped with around around 100amp peaks.

The lmx is pretty much finished, i just need to spend some time tuning the kelly controller and taking it for some test rides before a proper shake down in the woods. Ive had a busy and testing couple of weeks at home and in work so i am a bit out of rhythm with the bikes at present. I will try and make another video clip soon with some shots of the finished bike. I must say, at present the chain is fiercely loud
thanks for the info
are you using 2 of these? it says DC 63A, 2 together might work?

great to hear you almost finish the build. I just barely started :D
 
BCTECH said:
brumbrum said:
BCTECH said:
what kind of circuit breaker did you use?

Hi mate, I bought this one... https://www.ebay.co.uk/itm/63A-DC-C...495247&hash=item3f53e959ec:g:URUAAOSw3YNXYTfc

Not sure if it will be the correct ampage. I have an AC version , same amp rating, on my nyx bike and it have never tripped with around around 100amp peaks.

The lmx is pretty much finished, i just need to spend some time tuning the kelly controller and taking it for some test rides before a proper shake down in the woods. Ive had a busy and testing couple of weeks at home and in work so i am a bit out of rhythm with the bikes at present. I will try and make another video clip soon with some shots of the finished bike. I must say, at present the chain is fiercely loud
thanks for the info
are you using 2 of these? it says DC 63A, 2 together might work?

great to hear you almost finish the build. I just barely started :D

I only use one with my nyx and adaptto bike. We will see. If it trips easily i will buy a higher rated one. Anyway, at the moment i will be conservative with amps and throttle
 
BCTECH said:
brumbrum said:
BCTECH said:
what kind of circuit breaker did you use?

Hi mate, I bought this one... https://www.ebay.co.uk/itm/63A-DC-C...495247&hash=item3f53e959ec:g:URUAAOSw3YNXYTfc

Not sure if it will be the correct ampage. I have an AC version , same amp rating, on my nyx bike and it have never tripped with around around 100amp peaks.

The lmx is pretty much finished, i just need to spend some time tuning the kelly controller and taking it for some test rides before a proper shake down in the woods. Ive had a busy and testing couple of weeks at home and in work so i am a bit out of rhythm with the bikes at present. I will try and make another video clip soon with some shots of the finished bike. I must say, at present the chain is fiercely loud
thanks for the info
are you using 2 of these? it says DC 63A, 2 together might work?

great to hear you almost finish the build. I just barely started :D

I did my first test ride today, just up n down the street a few times, about 5% incline/decline road.
I changed the battery current setting in the controller software from 50%(which is max) down to 35%.
2dsp7ib.jpg


With peak amp at 135 and constant between 50 and 60amp. Not sure of top speed as the pole count calibration on the CA is completely out at the moment. It felt like at least 40mph probably more.
LMX recommend 150a max for the motor, so 135 seems a good programming judgement call from me. I was getting a fair bit of voltage sag about 7v as at the moment it is just a 20ah multistar lipo pack, which is pulling about 7C discharge at peak.

Initial acceleration is impressive. I can now understand why the seating position and handle bars are much closer together than an ordinary bike design..... Ability to put downward pressure on the front of the bike naturally with ease. I do like the riding position, true mx bike feel. I have deliberately used 30mm riser spacers on top of the forks and also a 50mm rise handle bar to get this high position.
The bike feels straight, solid, tight, taught, but this was only a short road run.
 
nice to hear, and i think you using the perfect amps ,I will try 40% it might give you the sweet spot , or first do allot of tests riding for a few hours and keep an eye on motor temperature

also much more than 160 peak amps is uncontrolable with such light bike ,
i will try a spot of 75 continues and 150 peak , seems sweet spot
 
maitilupas said:
nice to hear, and i think you using the perfect amps ,I will try 40% it might give you the sweet spot , or first do allot of tests riding for a few hours and keep an eye on motor temperature

also much more than 160 peak amps is uncontrolable with such light bike ,
i will try a spot of 75 continues and 150 peak , seems sweet spot


Yeah, just a few take-offs up n down the 200m road got the motor slightly warm to the touch. However, due to motor design i assume heat is felt pn the surface quite quickly
 
BCTECH said:
brumbrum said:
BCTECH said:
what kind of circuit breaker did you use?

Hi mate, I bought this one... https://www.ebay.co.uk/itm/63A-DC-C...495247&hash=item3f53e959ec:g:URUAAOSw3YNXYTfc

Not sure if it will be the correct ampage. I have an AC version , same amp rating, on my nyx bike and it have never tripped with around around 100amp peaks.

The lmx is pretty much finished, i just need to spend some time tuning the kelly controller and taking it for some test rides before a proper shake down in the woods. Ive had a busy and testing couple of weeks at home and in work so i am a bit out of rhythm with the bikes at present. I will try and make another video clip soon with some shots of the finished bike. I must say, at present the chain is fiercely loud
thanks for the info
are you using 2 of these? it says DC 63A, 2 together might work?

great to hear you almost finish the build. I just barely started :D

Btw, the 63a circuit breaker did not trip with 135a peak and 60a constant
 
Some final words if there is still anyone out there sad enough to want yet another instalment from me.....
[youtube]Im9nIkXXJUM[/youtube]

I promise I will try and get some ride footage in the coming weeks! In fact I met up with a chap who runs a local government funded MX track who has given me the go ahead to ride on the track. Though he did say I would have to have my own private session without other bikes on the track as my bike is a prototype lol and could be unsafe
 
Thing looks sick man! Thanks for the vid. I've always wanted a LMX bike but it will never happen :(

I do more commuting than pleasure riding anymore anyways

def get a ride vid
 
skeetab5780 said:
Thing looks sick man! Thanks for the vid. I've always wanted a LMX bike but it will never happen :(

I do more commuting than pleasure riding anymore anyways

def get a ride vid

Thanks mate, yeah it does look pretty sick and the ride is a thrill. I am 45 in few weeks and feel that I am running out of riding time with bikes like this, so it’s now or never for me. It has been a big spend and I owe most of it to a credit card company! But once I get an idea in my head that’s it,, I just had to have it
 
I use this method to get the ideal chain adjustment on my ice dirt bikes. I disconnect the rear sock while the bike is on a stand, then you can freely move the swing arm thru its travel. Chain drives want zero preload and just a little free play to work best.The chain will be tightest when the center lines of the drive sprocket, swingarm pivot and axle are in a straight line. Adjust the chain so there is no preload on it and has a slight amount of play with the swing arm at this location. When people adjust the chain at full sag they have a tendency to have insufficient slack. This creates a tremendous load on components when it’s actually too short to pass this tightest spot location, that makes things wear faster.
 
Dogboy1200 said:
I use this method to get the ideal chain adjustment on my ice dirt bikes. I disconnect the rear sock while the bike is on a stand, then you can freely move the swing arm thru its travel. Chain drives want zero preload and just a little free play to work best.The chain will be tightest when the center lines of the drive sprocket, swingarm pivot and axle are in a straight line. Adjust the chain so there is no preload on it and has a slight amount of play with the swing arm at this location. When people adjust the chain at full sag they have a tendency to have insufficient slack. This creates a tremendous load on components when it’s actually too short to pass this tightest spot location, that makes things wear faster.


That is really helpful information to know. Many thanks. I think the chain maybe getting too loose now after some initial test rides so i will try the method of getting the pivot point and sprocket centre's in line as you suggest. I can see you have had plenty of practise from the list of bikes in your signature
 
spektrolyte said:
Nice work. The 63A breaker is rated for use at 240v, so its more like 200A for a 72v pack.

Also, It is a DC breaker not an AC breaker which is designed for 240v domestic use, so all ok. But thanks for your concern :D
 
Ah right, thought it was like the one in my Raptor, didn't follow the link.

My Sabvoton is unlocked for 200A so a 63A domestic breaker fits the bill nicely.
 
Just a taster. Mainly fire roads/forestry. Still getting used to a different style of riding with this bike now that i have freedom to move my legs off the pegs and bum along the seat. The speed reading is completely off at present, and has lots of lag. I can feel the motor slowing the bike going down hill, which is something that can hopefully be dampened if not completely eliminated in the controller settings.

[youtube]JNJ8HhjrWec[/youtube]
 
Back
Top