LaFree modifications?

F

fredtr

1 mW
Joined
Jul 25, 2009
Messages
15
Would like to modify LaFree to increase top speed. Has anyone tried this, or have a schematic or suggestion?

Thanks,

Fred
 
which version of the LaFree? is it one of the older ones using the 400W Bottom Bracket Drive? PAS drive with the sensor built into the cranks?

if so there is no way to modify the existing electronics for higher speed.

if you are willing to ditch the PAS controler and mount a throttle on the handlebars you can add a battery and a 36V brushed controller. i have never seen a LaFree modified this way. but a similar bike using the same drive was made by Merida for several years. there is some info on the V is For Voltage forum how to modify these drives.

http://visforvoltage.org/forums/electricrides/bicyclesandpedelecs/merida

rick
 
Sorry for slow response, bought the Lafree and loaned it to my niece the next day. She brought it back last night, yes seems to be 400 watt, sensor in the crank. Having a problem with it, turn it on, beeps twice, then all 5 power lights flash about once a second forever, and it does not run. Occasionally it would turn on correctly work for 30 seconds or so then return to that fault. Took it all apart, couldn't find any problem, trying to figure out the separate battery negative/common circuit (common to B+ 21.6 volts). Hit common to B+ with 24 volts thinking it was running too low, and after that it started to work, took about 8 mile ride, but that sure isn't a fix. Anyone know what 2 beeps and 5 power lights flashing once per second means? Batteries are new, runs about 26 volts negative to B+.

Did have helpful suggestion from two members to reduce the number of rear wheel magnets to increase top speed, seems to work.

Thank-you,

Fred
 
fredtr said:
Sorry for slow response, bought the Lafree and loaned it to my niece the next day. She brought it back last night, yes seems to be 400 watt, sensor in the crank. Having a problem with it, turn it on, beeps twice, then all 5 power lights flash about once a second forever, and it does not run. Occasionally it would turn on correctly work for 30 seconds or so then return to that fault. Took it all apart, couldn't find any problem, trying to figure out the separate battery negative/common circuit (common to B+ 21.6 volts). Hit common to B+ with 24 volts thinking it was running too low, and after that it started to work, took about 8 mile ride, but that sure isn't a fix. Anyone know what 2 beeps and 5 power lights flashing once per second means? Batteries are new, runs about 26 volts negative to B+.

Did have helpful suggestion from two members to reduce the number of rear wheel magnets to increase top speed, seems to work.

Thank-you,

Fred
Click to expand...



Most common intermitent fault is a problem with the brake handle sensor switches. When activated , they make the motor stop. also will cause the self check to fail. there is a check sequence where you are supposed to squeeze the brakes and twist the throttle, but at a loss to remember. Ask BXMD Bob from SLO California.
 
Found the manual:

http://www.wrower.pl/instrukcje/Giant/2000-Lafree_Sports_Manual.pdf


section 7.4 is self test operations.

tailwinds

d
 
So I have made that very mod your talking about, going faster, I turned my Giant LaFree into a 36 volt bike. I removed all the electronics and installed a aftermarket controller. I saved the electronics in case I ever need them for my stock bike (I have two Giant LaFrees) or if I want to return this modified bike to stock voltage. I was able to gut the battery box and install 38120 LiFe batteries. The bike is much faster and the motor seems to handle it well, I felt the motor after some hard runs and it is just warm to the touch.

Right now I'm dealing with a problem where the stock LaFree throttle will not turn the motor completely off or give me full throttle. It was fairly straight forward for someone who likes to modify things, other then the fact that I cut the front half of this women's bike off and grafted on a full suspension MTB frame.

It's a blast riding it on the off road trails, can really haul ass and still be in control of the bike.

More gears would help with all the extra power, a higher top speed could be archived and offroading at times requires you to go super slow up really steep hills, while making turns.

It's so much fun, it makes me want to explore building a even more robust MTB. I think a frame mounted motor and driving through the gears is the only way to go for offroad. I would like to get a hold of another Giant LaFree and see how hard I can push the motor and drive. I can see that regular MTB components (wheels, tires, spokes) would not hold up to the added abuse for long. The speeds I'm going on the bike I built is much faster then what you would normally hit on a MTB and that seems to be pushing the limits already.

Deron.
 
Oh and I did have a problem with my stock LaFree. The little test spot where you insert a paper clip end into it to get into the test mode was stuck on. The rubber seal came out of position and was keeping the test button pushed all the time. I repositioned the rubber seal and all was well.

Deron.
 
Also from my experience, 24 volts with that gear ratio is only good for about 20 MPH. 36 volts will get you up to about 25, 48 volts will get you just under thirty. I tested different voltages with some SLA batteries I had and was pedaling in each case. The batteries I had were worn, a good set of LiFe would be a plus. Anything over 20 MPH and you really start to notice how much the wind effects you. I would ride one direction into the wind and then the other with the wind and that would make a few MPH difference.

Deron.
 
Deron,

Do you have any of the stock Lafree sport parts you would consider selling? Would like to try the small board in the battery pack or a controller.

Thank-you,

Fred
 
Put a scope on the C terminal from battery pack, sends a low going pulse once a second to the controller. Someone mentioned they had a problem with the small board in the battery pack that does this, anyone know anything about the change to the board?
 
Got some stronger glasses, small board in battery pack contains a BQ2013a battery gauge part that communicates serially to the controller. Once a second the controller requests the status of the battery, that is what is sent on the center conductor, marked common. Anyone have one of these boards for sale?
 
Needed to revive this thread to see what might be possible with a LaFree Sport that a 70 yr. old woman has here. She has been stranded with a heavy bike a few times and although she really likes it she is kind of shy about using it now. She is not a speed demon but she and the bike and the hills around here do put enough strain on the system to suck the batteries dry before she is done having her jollies so I am thinking an upgrade in battery type over the SLA's would give her some more time in the saddle? Not looking to get in to alot of cost or having to switch out all the electronics so sticking with 24v is probably the way to go? Any suggestions from the fine folks here?
 
if she is 70 and rides a bike, get her to a 36V lifepo4 setup. she obviously can handle it and will need more assist over time too. bike will be lighter too, and i agree with deron, go to a useful controller as well. maybe we can get bill to visit her on the coast when he makes his portland to beach run this summer. make it a local new's hooker: video, old and young, lafree and WAW velomobile. get them to use it on channel 9 here in portland.
 
Thanks for the reply's. I was considering upgrading the voltage as I deduced from the other posts that the motor could take it but the cost of a new controller and the 36v battery upgrade may put the cost out of reach for her fixed income.

While the NiCad idea is sound it is a bit beyond our resources here to put something together off the cuff like that. Looking more for a plug and play battery for cost and convenience sake. Seems like a 24v 12ah lifepo4 setup may be worth a try at least as it can be plumbed in without additional electronics and use the PAS which she is used to. The only problem being that it won't fix the issue of the bike shutting down if it is pedaled in too high a gear from a stop.

If Bill is coming down to this part of the coast in the summer for sure we would like to know when that will happen? The ebike movement needs all the positive press it can get so perhaps something might work out along those lines.
 
Well I did some more research based on the stock battery housing dimensions and found that a 24V 10AH setup like the Vpower ebay sales deal would fit in there pretty much like a glove including the BMS I think. About half the weight of stock at 3.2kg also. Won't do much to extend the range of the bike however. The 12 AH version is another 1/2" longer and that might be doable but not without a mod to the stock box. Not sure if the extra $50 or so in battery cost and mods will be worth it for this project. In reality she really only needs to be able to go 12 miles or so for her errands but it is somewhat hilly in a few spots. The (re)search goes on.
 
I converted LaFree to conventional bike using this controller:

http://www.allelectronics.com/make-a-store/item/MSP-150/24-VDC-40-A-MOTOR-SPEED-CONTROL/1.html

it works great and was easy to do.

Am using the standard LaFree 24 volt batteries. Have built NiCad packs for other bikes, and like them. But even with the different controller, using the same battery and built in charger, the bike looks and works pretty much the same. Think you get more range because as a conventional electric bike, motor does not disengage during the dead part of pedal motion.

Don't know what range she wants, could add some batteries on the rack in back and connect with a high current switch or relay. When the mains rundown, flip the switch like a spare tank.

How old are the batteries she has? SLA's don't last all that long, especially if they get run-down. Bought new batteries from Gruber, think they were about $25 each.
 
Fred may be on to something, first step might be either replace batteries with good ones, or measuring the AH draw and need.

Also, the stock Lafree charger does not geive 100% recharge until 4 hours on the green light.

sorry for not catching this stuff earlier.

d

edit

fresh batteries and a better faster charger for opportunity charging might be all that is needed.

d
 
Thanks again for the feedback. I guess there is not alot of love for the idea of going over to the Lifepo4 battery. Granted the cost of getting some new SLA's which is about $80 w/shipping charges unless I can find some in stock locally (good luck with that here at the Ft.) and a charger upgrade of ?? will be cheaper up front. DD if you have any suggestions on the whereabouts of a charger as you describe it would be great btw. So let's say $100 + for bringing it up to stock form and another $50 or so to swap out the controller and do that mod? I see that is cheaper than the $300 it would take to do the Lifepo4 conversion but what is attractive about that is the amount of charges it will take over time, reduction in weight, better overall performance? Oh well, a decision will be made here after a bit and anyone else that cares to put in their 2V is welcome.

I know alot about bikes but am on a steep learning curve about electronics and this forum is a wealth of info for sure. Alot of it way over my head but I am willing to learn.
 
My 2 cents would be to buy new batteries, and make sure you leave the charger on 4 hours after light goes green. I liked the controller change, but it isn't necessary. If you remove a couple of the magnets on the rear hub, it does increase the top speed a few miles per hour.

Try e-bay or Gruber (Phoenix) for the batteries.
 
nope, cheaper to pick up a 36V10Ah pack from travis when you are in portland. save the shipping, then get her a real controller so she can turn the throttle and not have to stand on her 70 year old ankles on the pedals on that hill. give her a break, she is 70 and riding a bike, what more could you ask for? she can handle the power too. being old doesn't rob you of the pleasure of going faster either. can't take the money with you either, she won't be riding so much she burns up the motor either. so 36V, minimum of 500-600W controller. you guys take away the advantage we have over PAS, which should be outlawed. along with speed limits, imho.
 
Thanks once again. Don't know of travis in stumptown but would for sure prefer to use him than not for the battery. I'll be in the metro area a bunch end of this month and next so I'll try and find him.
 
Lets see what we know and dont know and do some review .

First some questions;

How old are the batteries, have they ever been replaced? If replaced did she get the right repacements (B and B B BRand EV specific model. Gruber or Panasonic?)

What exactly in dollars are the budget goals?

Is the ebike well maintained bicycle wise; tire inflation, brakes, wheels trued, chain lubed?

How fast does the lady go on the bike? How heavy the load? Does she contribute a lot pedaling, or only minimal?

does she charge the pack while going on errands? AT home did she leave the pack on the charger several hours after going green?

How tough are the hills; slope and length?
--
I owned a Lafree Sport as my first ebike; I worked on many. I never asked it to go over 9 miles without some charge. If you have a Lafree, you need to know how to take care of SLA batteries; charging them often; minimizing the time uncharged, minimizing heavy current draws -- all these things maximize range and battery life. If these batteries have many months on them and havent been cared for very well, they have reduced range and possibly maximum current delivery capacity. Staying in the lowest useable gear increases motor efficiency.,

The Lafree is a heavy bike. It has a nice 400w brushed chain drive motor with almost 1000w peak power. But that power and energy must come from its 24v SLA batteries. That is 40 amps peak when the rider forgets to downshift before stopping, then starts up in much too high a gear- for the motor and the legs. Heavy current draw like this decreases the true SLA AH's available versus any other chemistry at identical AH's, by a big factor, maybe 35% especially by a user not managing maximum current draws.

It is very nice to have a chain drive ebike IF one uses the gears correctly; but on a standard rear deraileur bike it is difficult for the operator to downshift several gears from a very low speed up a hill. This is mainly a Pedal assist bike with a short term throttle(~5 seconds) for tough spots, with a off/ full power/ economy switch on the handle bars.

As it sits, I am not sure this is a great match of an ebike for a 70 year old lady. It has to be ridden and shifted correctly, it is heavy, it has a short range, the SLA pack and charger need to be understood and used accordingly. It is a step thru frame, known as womens frame in previous days.

The chain drive is fine, but I would prefer a nexus rear internal hub that can be shifted more easily. I would have prefered a Nicad pack stock, a very rugged chemistry with pretty good current capabilities. Dont know if this user needs a chain drive, but she does have one.

Anyway, lets see how the reponses to the above questions come in. If the owner only has
$100, they get good fresh batteries and some advise on battery care and riding .
 
deardancer3 said:
Lets see what we know and dont know and do some review .

First some questions;

How old are the batteries, have they ever been replaced? If replaced did she get the right repacements (B and B B BRand EV specific model. Gruber or Panasonic?)
Batteries are at least 3 years old, that is why we are looking in to other options or just going back with stock


What exactly in dollars are the budget goals?
Say $300


Is the ebike well maintained bicycle wise; tire inflation, brakes, wheels trued, chain lubed?
Yes

How fast does the lady go on the bike? How heavy the load? Does she contribute a lot pedaling, or only minimal?
She has had it maxed out for speed she claims and carries moderate to light loads and does pedal because she has to with the PAS

does she charge the pack while going on errands? AT home did she leave the pack on the charger several hours after going green?
No and Yes

How tough are the hills; slope and length?
5 or 6% up to 1/2 mile in length
--
I owned a Lafree Sport as my first ebike; I worked on many. I never asked it to go over 9 miles without some charge. If you have a Lafree, you need to know how to take care of SLA batteries; charging them often; minimizing the time uncharged, minimizing heavy current draws -- all these things maximize range and battery life. If these batteries have many months on them and havent been cared for very well, they have reduced range and possibly maximum current delivery capacity. Staying in the lowest useable gear increases motor efficiency.,
Duly noted

The Lafree is a heavy bike. It has a nice 400w brushed chain drive motor with almost 1000w peak power. But that power and energy must come from its 24v SLA batteries. That is 40 amps peak when the rider forgets to downshift before stopping, then starts up in much too high a gear- for the motor and the legs. Heavy current draw like this decreases the true SLA AH's available versus any other chemistry at identical AH's, by a big factor, maybe 35% especially by a user not managing maximum current draws.
Duly noted


It is very nice to have a chain drive ebike IF one uses the gears correctly; but on a standard rear deraileur bike it is difficult for the operator to downshift several gears from a very low speed up a hill. This is mainly a Pedal assist bike with a short term throttle(~5 seconds) for tough spots, with a off/ full power/ economy switch on the handle bars.
Agreed

As it sits, I am not sure this is a great match of an ebike for a 70 year old lady. It has to be ridden and shifted correctly, it is heavy, it has a short range, the SLA pack and charger need to be understood and used accordingly. It is a step thru frame, known as womens frame in previous days.
But at this point it is the one she has. I could buy it from her I suppose but for what it is worth and her top budget amount it would not do much to get her anything better that I can see so for now I think she will stick with it.

The chain drive is fine, but I would prefer a nexus rear internal hub that can be shifted more easily. I would have prefered a Nicad pack stock, a very rugged chemistry with pretty good current capabilities. Dont know if this user needs a chain drive, but she does have one.
An internal hub would be a good addition for sure. The newer LaFree lites had a NiCad pack I believer?

Anyway, lets see how the reponses to the above questions come in. If the owner only has
$100, they get good fresh batteries and some advise on battery care and riding .
Thanks for taking the time to come back with such an insightful response.
Click to expand...
 
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