Saving a Giant Lafree

[SaxMan]

Hi everyone,

I am working on fixing up a Giant Lafree Sport. I am a volunteer with the Maryland-National Capital Park Police, just outside of Washington, D.C. The Lafree was left abandoned in one of our parks and brought in to our abandoned property section. Usually bikes that are picked up are held for 90 days waiting to be claimed. If no one claims them, they end up going to the recycler. I spotted the Lafree and convinced my supervisor to allow me to pull the bike to fix it up for the use of the department. I have brought it home and stripped it to the frame. Amazingly, despite being exposed to the elements for a long time, the motor still works.

The only hiccup I've had is when I opened up the transmission, all the parts spilled out unexpectedly. I did get the motor back together, save a few u-shaped magnets. Does anyone have an exploded view of the Lafree's transmission? I was thinking since I did have the transmission open that I could remove the pieces that cause the motor to cut out at 20 mph (32 kph) per our government's regulations. Will the motor still work if I take these pieces out? If not, could I fabricate something to make the sensor "think" the cutout is still there?

I'm looking forward to getting this pedelec fully restored and put into our department's service. I'll keep everyone posted on the progress.

David C.
Damascus, Maryland, United States

 

[flecc]

This SLA batteried Lafree series from 1999-2001 was not popular in the UK and mainland Europe though successful in the USA, so little is know here about them David. Someone at Giant USA may be able to help legitimately since the 20 mph limit is Federal law as you know and some States have higher assist speed limits.

Can you give us some idea of what the pieces are that you mean to remove? If it's mainly a ring of magnets with a pickup sensor, it probably only performs the confirmation pedalling, rather than the speed limiting function.

 

[SaxMan]

There is a line from the rear wheel sensor that attaches to the outside the transmission. On the internal side of the transmission, there is a part that looks like a lever which is connected to a spring-loaded plunger type device. So far as I can tell, it appears to be magnetically actuated and that once the wheel hits a certain amount of RPMs the magnet would cut off and stop the gears from turning. If I take out the parts that stop the gears from turning, technically, that should defeat the ability of the governor to cut off the motor. I can post pics of what I'm talking about as well

Even though it's a bit messy, I can always try this through "trial and error" and see if I am able to get a working result. I have a separate power supply that I can use to diagnose the electrical system.

While tearing the bike down, I came across the likely reason the bike was abandoned: One of the battery terminals was bent down at a 90 degree angle instead of sticking up in the vertical position. Hard to believe a simple problem like that led someone to discard the bike like yesterday's trash. At least they were nice enough to leave the key with the bike.

 

[Clockwise]

Instead of taking the bits out of the hub I would try putting a volt meter on the wire, you might be able to just slip a resistor in somewhere along the wire to reduce it so it will think you are doing 7.5 instead of 15 and give you a new top speed of 30(or whatever you want if you do the math for the resistor. Take a few readings so maybe 5mph, 10mph, 15mph they should line up kinda. Duct tape the volt meter to the handlebars or try get the bike on one of them rolling road type things as you do it.

Sounds like a very fun project.

 

[SaxMan]

I traced the wires and it is not a direct connection from the wheel sensor to the cutoff. It does go through a rather primitive circuit board (compared to later models). In addition there are cutoffs when you apply the brakes...that is something I definitely don't want to disable.

I did figure out where my missing pieces went. The problem I'm running into now is when I close up the transmission, something is binding. The gears spin free and the motor will turn until I start torquing down the bolts. Obviously, something is not in the right place. The only thing to do is to open it up, check everything over, make adjustments and repeat the process until I get a "winning" combination.

I will contact Giant and see if they have any kind of technical info to make my life a bit easier. This project is definitely going to be a long term one.

 

[SaxMan]

I found my binding issue: It was the ratchet for the cranks. The ratchet was completely bent out of alignment with the gear teeth. It took me a few times to get it adjusted properly, but everything finally went back together properly. I hooked the motor back up to the gearbox and everything is now whirring along smoothly.

Now, it's off to tackle the wiring harness and the rest of the electrical system. Once I get past this hurdle, then the rest of the project is just like fixing up any other bicycle.

 

[SaxMan]

Tonight, I took a break from the electrical work and decided to clean up the frame and prep the kickstand for painting. This is definitely a '99 LaFree. It's serial number: GP0000097, which, if I'm reading this right makes it the 97th LaFree ever constructed. The motor's serial also starts with "99", which seems to confirm its pedigree.

I don't know if that makes this a particularly desirable or collectible bike, but it does make me that much more determined to get this bike on the road again.

 

[SaxMan]

Today's Question: I opened up the battery pack so I can replace the long-dead batteries. Both batteries were taped to each other using what appears to be white gaffer's tape. Is it necessary (or desirable) to tape the replacement batteries together?

The wiring harness is back in the bike. Once I get the replacement batteries, we'll have the moment of truth. I know I have a running motor, and I know I'll have good batteries. The big question is whether the wiring is still good. If I can get over this hurdle, then all that is left is "regular" bicycle work.

 

[flecc]

The tape isn't vital, but it's probably a good idea to bind them together again so the upper one doesn't hammer and damage the lower one when riding on a bumpy road.

 

[SaxMan]

The tape isn't vital, but it's probably a good idea to bind them together again so the upper one doesn't hammer and damage the lower one when riding on a bumpy road.

Got it. Thank you. I reattached the motor tonight and a couple of the plastic pieces that hold the battery in. I'm heading over to a battery store tomorrow to pick up a new pair of 12-12 batteries. I've got my fingers crossed!!!

 

[SaxMan]

Kind of a disappointing night. I got the new batteries, charged them up, put them in the bike, and nothing. I'm getting all five LEDs blinking with a beeping noise. I broke out the multimeter. I'm getting 26 V at the battery terminals, but 0 on the motor end. I pulled the harness back out again and think I've narrowed down the problem:


DSC_1304 by onyxsax, on Flickr

I'm getting 26 V off the pink and orange cables going into the black block, but zero on the red and white ones. My guess is this black block holds some kind of fuse? The problem is figuring out how to access it. I've taken out the screws that hold the circuit board in, but the board is not budging one bit. I'll try hitting it with some PB Blaster to free it up.

If I can't get this to work, my next course of action was to fabricate a simpler wiring harness, have one lead coming off the battery go through a voltmeter (for battery life) and potentiometer (for throttle). The only downside is losing the brake-cut off, but on the other hand, I wouldn't be dealing with a speed governor either.

 

[shemozzle999]

Hi Saxman,

I think the black box is a relay - the white and red wires are for the energizing coil to operate the relay switch contacts that the orange and pink cables are attach to, you should be able to hear it click when you switch on and off although it does mean it is working as the contacts inside can sometimes with repeated use soot up with spark/arcing and not make a connection. There appears to be 2 locking tabs on the outside edge of the relay box and if you can prise them back the whole base might be able to be withdrawn upwards from the box while leaving the box in situ, exposing the inner workings so that you can check the condition of the contacts and maybe clean them. I would only do this if you run out of other ideas as it could break the control permanently, or alternatively you could take the orange and pink terminals off and short them together bypassing the relay to see if that makes the motor work.

When I google searched for the Sport it appears that there should be 3 battery pin connectors, as the control electronics require a 12v feed and that there have been past problems with this pin not making a positive connection, perhaps you could check that out.

 

[johnc461165]

same problem here at the bottom of the page
https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&cad=rja&ved=0CF8QFjAG&url=http://visforvoltage.org/forum/5003-giant-la-free&ei=vL3jUcWYG9Ty0gXV_4HoCg&usg=AFQjCNG6JkZ0PUzHOBX7_gklGmPCnPh1ow

 

[SaxMan]

Thanks for the tips. I will check the third pin connection to the battery and try again.

I'm not overly pressed if I have to bypass the onboard cicuitry I know I've got a working motor and I know have a working battery pack. It would be a shame to have to abandon the project over the wiring. It appears that some of the posters on the thread that you sent me the link to have already done the same thing.

 

[SaxMan]

Another night of troubleshooting did not yield any kind of progress. I did find out the black box was a relay and it was working fine. This bike spent a fair amount exposed to the elements. Trying to find the issue could literally be like finding a needle in the haystack.

At this point, I'm going to go ahead and fabricate a much simpler wiring harness. I know I have a working battery pack and I know I have a working motor. I just need to make the "in between". I'm hoping I can use the existing throttle mechanism and on/off switch. I also figured I would get a voltmeter and tap it off the battery terminals to give me an idea of how much battery life I would have any any given time. Meanwhile, I'm going to work on some of the "bike" aspects of the Lafree and wire in the new harness once I have a bit more of the bike fixed up.

 

[flecc]

Link to download the Giant Lafree Sport Manual.pdf from my website.

 

[shemozzle999]

Hi Saxman,

I think the black box is a relay - the white and red wires are for the energizing coil to operate the relay switch contacts that the orange and pink cables are attach to, you should be able to hear it click when you switch on and off although it does not mean it is working as the contacts inside can sometimes with repeated use soot up with spark/arcing and not make a connection. There appears to be 2 locking tabs on the outside edge of the relay box and if you can prise them back the whole base might be able to be withdrawn upwards from the box while leaving the box in situ, exposing the inner workings so that you can check the condition of the contacts and maybe clean them. I would only do this if you run out of other ideas as it could break the control permanently, or alternatively you could take the orange and pink terminals off and short them together bypassing the relay to see if that makes the motor work.

When I google searched for the Sport it appears that there should be 3 battery pin connectors, as the control electronics require a 12v feed and that there have been past problems with this pin not making a positive connection, perhaps you could check that out.

Hi Saxman,

I edited an error in my previous post in bold text.

What I was trying to imply was that although you had 26v readings on both the pink and the orange wire if the contact is dirty it will not pass full current to the motor so un-pluging them and shorting them together will check whether this is the case or not.

There are detailed self tests described in the manual that you can try to ensure the torque sensor, brake cut out, throttle and speed sensor are all fully functioning.

If you want to go down the replacement route, others on endless sphere have done this:

http://endless-sphere.com/forums/viewtopic.php?f=2&t=31167

 

[SaxMan]

Hi Shemozzle,

I actually did bypass the relay, to no avail. This bike sat exposed to the elements for a LONG time. It had been at least 120 days sitting out in our Abandoned Property section, and who knows how long it sat outside before it was impounded. Frankly, I'm amazed that I got the motor to run as smoothly as it is running right now. Like most bikes that have been exposed, it almost seems Quixotic how one piece can be almost completely rusted, yet another piece looks virtually new.

Thanks for the link to the thread about the controller. I may try that option if my homegrown attempt doesn't work.

Right now, I'm working on reconditioning the front end: Fork, quill stem, handelbars and headset. I want to get these back on the bike before I start working on a rewiring it. All needed a fair amount of elbow grease to remove the surface rust and clean them up.

 

[SaxMan]

Link to download the Giant Lafree Sport Manual.pdf from my website.

Awesome! Thank you!

 

[flecc]

Awesome! Thank you!

A pleasure. Thanks to Shemozzle999 who supplied the manual for me to host on my site.