Re: The Official Yamaha Chappy (LB50) Thread!!!

Jack Rutherford /

My stator on my friend's bike. This thing is actually really zippy with stock exhaust. (edited)

Re: The Official Yamaha Chappy (LB50) Thread!!!

Eric Migliorino /

I took a closer look at the two stators. The key difference between the two (other than the stator plates being slightly different) is that there are 3 wires coming off right hand coil on the LB80 - yellow, green and green with red stripe wires, plus the 4th black wire coming from the condenser. The LB50 will have 2 wires coming off the right hand coil - yellow and green with red stripe plus the third wire is the black coming off the condenser.

Now carefully look at that right hand coil. It’s segmented into 3 wire windings. On the LB80 stator, it pulls from each of the 3 segmented wire windings. On the LB50 stator, it looks like two of the smaller coils go to the yellow or green with red stripe wires and the third winding gets fed into the left wire winding.

So what do you do? 2 choices.

1. Get a 2 position key switch, similar to what the LB50’s have and skip the green wire entirely. Issue here is there maybe other items dependent on this circuit. I see another green wire but it looks like it controls the high low beams. I think this circuit may be independent of the green wire off the stator but I could be wrong. This approach, you avoid messing with the stator, but some items that depend on that circuit may not work that I’m missing. Again, you will need to switch to a two position key and possibly trace every circuit that green wire ties into.

2. Making changes to the LB50 stator. Disconnect the right coil from the left coil (Small black wire connecting right coil to left). The left coil wire attaches to the bottom screw holding the coil to the stator. The wire coming off the wire winding on the right would tie into the extra green wire you have. Just closely follow what you see on your LB80 coil and do the same to the LB50 coil. Also use a multimeter to test for direct shorts (no resistance = Short). This will hopefully avoid burning out any of your wire windings.

Hope this helps, keep us posted as to how things work out.

Eric

Re: The Official Yamaha Chappy (LB50) Thread!!!

SHES ALIVE!!!

Re: The Official Yamaha Chappy (LB50) Thread!!!

Jack Rutherford /

Thanks Eric for looking into that. I took a look at the two stators as well but not quite as closely as you. I have to figure out what I want to take on given that this is not my bike. My buddy got a pretty good deal on it and I'm thinking he can spend $100 on a stator.

I really like the stock set up. Nice acceleration and quiet.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Jack Rutherford /

How about the rear fender extension some previous owner added? What's up with that?

Re: The Official Yamaha Chappy (LB50) Thread!!!

Jack Rutherford /

So I was thinking about the stator issue - 3 wire vs 4 wire. And I thought, why can't I just use the 3 wire stator and not connect the wire controlling lighting. I think the green wire is not ground. The stator must be sending current through all four wires. To use a three wire stator, maybe I just give up the lights for the time being and see if it will work.

thoughts?

Re: The Official Yamaha Chappy (LB50) Thread!!!

shayne zroback /

Just connect the wires you can identify. You should be fine. I did the same thing with my lb80 stator and put it on my 50. I just taped up the extra wires. FYI the lb80 i have has a 5 wire connector.

Re: The Official Yamaha Chappy (LB50) Thread!!!

does anyone have any idea what kind of header flange/collar is used on these chappys? interested in DIYing an exhaust and do not want to cannibalize the oem pipe which is in pretty good shape.

Re: The Official Yamaha Chappy (LB50) Thread!!!

> kenneth gilbert Wrote:

> -------------------------------------------------------

> does anyone have any idea what kind of header flange/collar is used on

> these chappys? interested in DIYing an exhaust and do not want to

> cannibalize the oem pipe which is in pretty good shape.

Why not simply copy what you have ?

Re: The Official Yamaha Chappy (LB50) Thread!!!

You can easily just copy the flared end that mates with the cylinder, its nothing special. The threaded nuts are available on Ebay. In the past I have just cut up the factory exhausts and used their headers

Re: The Official Yamaha Chappy (LB50) Thread!!!

> The threaded nuts are available on Ebay.

for some reason it never occurred to me to look there. found one right away!

Re: The Official Yamaha Chappy (LB50) Thread!!!

> Hunter Skiff Wrote:

> -------------------------------------------------------

> The threaded nuts are available on Ebay.

Aren't they still available from Yamaha ?

Re: The Official Yamaha Chappy (LB50) Thread!!!

Hey guys, I have an 1981 lb50 that needs a light bulb. Have you guys had any luck with ordering online, if so what site?

Another option I've been told is to get a different light assembly from a Honda?

Thanks,

Michael

Re: The Official Yamaha Chappy (LB50) Thread!!!

Eric Migliorino /

Michael,

Is only the bulb burnt out or are you missing parts or even the whole headlight assembly? Depends on what you need. You can get the entire assembly off eBay, which comes in a chrome version. Not sure the quality though? You can still order the sealed beam from Yamaha but it’s expensive.

If it’s just the bulb, many people carefully cut out the old bulb leaving a hole to put in something replaceable. I believe there are tutorials on moped army but it is basically just cutting the bulb where it is soldered to the housing. That or maybe just unsolder it? Never tried, but chappy I bought had it cut out. I bought an LED bulb off Amazon as the halogen bulb the person put in before me was not bright. They make 6v versions that will work with the factory plug. Now note these are really meant for DC current but so far has worked with the AC current produced by the chappy’s little coil. Any of these bulbs will have 3 electrical connection tabs. Connect the bulb to your factory harness. Start the chappy up and make sure the high and low beams work correctly. If good, see how the bulb would fit into the old sealed bulb housing. See roughly where the 3 tabs for holding the bulb in would line up (the 3 tabs are in a triangular pattern) and drill 2 small holes near each tab (you should have 6 small holes). You use these small holes to feed solid metal wire through and twist around the tab to hold the bulb in. I’ll try taking apart my headlight and posting a picture, so you can understand.

The other option I did was buy a bulb assembly with a replaceable bulb. Have a chappy I’m rebuilding now, just haven’t had a chance to put in it yet so can’t comment yet as to how well it works.

Both links off amazon are below.

Hope this makes sense.

Eric

https://smile.amazon.com/gp/aw/d/B07GNY1LTD?psc=1&ref=ppx_pop_mob_b_asin_title

https://smile.amazon.com/gp/aw/d/B07HFMLW2H?psc=1&ref=ppx_pop_mob_b_asin_title

Re: The Official Yamaha Chappy (LB50) Thread!!!

Eric,

Thank you the detailed response, I apologize for leaving some details out on my post. The headlamp bulb burned out, when I got a replacement at a nearby auto stop that also burned out after install. Does that mean it is an electrical issue since there are no resistors?

I will be happy to take a look into modifying to get the bulbs off ebay working.

-Michael

Re: The Official Yamaha Chappy (LB50) Thread!!!

Eric Migliorino /

Maybe it’s just the wrong bulb? Should not burn out that quick. Do you currently have a good 6v battery installed? I believe the way the chappy was set up was for the battery to absorb some of the variation in power output. Therefore I’ve heard of people burning out bulbs quickly due to not having a battery. I always have had a good battery installed so can’t say whether this is 100% accurate. What I do know is mopeds originally were supposed to have a battery to operate the optional blinkers on them. This was required by the NHTSA, just like you see that little peek hole to check your brake linings.

My assumption is you either got the wrong bulb or it was defective. Bring it back to the parts store and have them exchange it for free since it was defective. Tell them no way a tiny 6v moped is powerful enough to blow a headlight that quickly. If still no success with new bulb, tell the parts store it’s the wrong bulb and do the modification for the LED bulb. It’s $10 and much brighter than an incandescent bulb, plus probably cheaper too.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Eric,

Brand new lithium battery. I will go back to parts store and am very interested in that LED bulb mod for my LB80, which I drive a lot at night.

Have you had good results using the LED (brightness, range)?

Re: The Official Yamaha Chappy (LB50) Thread!!!

Dirty30 Dillon /

Chappy really likes battery in line to regulate and float spikes. But that said, I rode for a long time with no battery and never blew a bulb.

I am going to guess that you have a bad ground somewhere that is causing poor continuity.

LED and lithium is no doubt the future, but I have also had really bad experience trying to integrate modern tech into an old system. LED bulbs are best used in a modern housing with proper optics and I've had bad luck using Lithium/AGM batteries in old points systems. The on-board electronics in modern batteries don't really like the huge inconsistencies of old ignitions.

Re: The Official Yamaha Chappy (LB50) Thread!!!

fitted a 16t front sprocket on the lb50pj this weekend (stock 32t in back). calcs say it's about 23% taller which puts it around where the lb80 is. it's a tiny bit shorter than switching out the rear to a 25t and keeping the 13t up front.

cruise very comfortably at 30-35, sustained flat ground run 37-38 or so. other mods are shaved head, polini 72cc, vm20, mlm intake.

had to relieve the tranny case slightly (a few mm) to clear the chain, the sprocket itself had no interference.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Dirty30 Dillon /

Y'all getting wild with displacement claims.

The Chappy Polini Kit comes out to like 63cc in reality. 45mm =/= 70cc automatically

Either way, you numbers seem right, I am seeing like 32-33 flat ground and 35-36 pushed with stock gearing. VM20/Carbon Reeds/Polini 45mm cylinder and matching Polini Pipe.

I really wish the 4-speed clutched Chappy motors were imported, as this bike with that train would be killer. As they are near impossible to find overseas, still planning the PW80 route once the project comes time.

Re: The Official Yamaha Chappy (LB50) Thread!!!

The break in for my Polini is done. Bike will do mid 30s comfortably (13/28 gearing) and will wing to 43mph if you gave it time. Will post an update video this weekend. Got a PW80 carb in the mail today, going to swap out the stock carb and see what gains are achievable.

Question: Has anyone noticed their factory LB50 speedo is way off? It seems accurate under 10mph, but after that it reads really under. Cruising this past weekend, 35MPH verified on my gps and on my LB80, and my LB50 is reading 27-28. It is possible these old speedometers were only calibrated for slow speed?

Re: The Official Yamaha Chappy (LB50) Thread!!!

> Hunter Skiff Wrote:

> -------------------------------------------------------

> Question: Has anyone noticed their factory LB50 speedo is way off?

Most , if not all , factory bike speedometers are 'off' . Some happen to be fairly close , but ...

Re: The Official Yamaha Chappy (LB50) Thread!!!

Eric Migliorino /

My LB50 is somewhat close to accurate but the faster you go the more inaccurate it gets. I downloaded an app on my phone to compare. When I was doing 38 according to the app, the speedo showed a hair over 35. What you are quoting seems a bit too far off. Check the speedo gear in the hub to make sure you aren’t missing any teeth. Otherwise I’m thinking your speedo is out of calibration.

Re: The Official Yamaha Chappy (LB50) Thread!!!

> Dirty30 Dillon Wrote:

> -------------------------------------------------------

> Y'all getting wild with displacement claims.

>

> The Chappy Polini Kit comes out to like 63cc in reality. 45mm =/= 70cc

> automatically

damn only 63cc??

> I really wish the 4-speed clutched Chappy motors were imported, as this

> bike with that train would be killer.

totally agreed. an mt would totally transform this bike, with better low end and better top speed.

I've been tossing around gearing so tall that I would use "low" on the transfer case by default. ive tried the shift from L to D while on the fly (>20mph) and off throttle and the dog engagement is no more jarring then while stopped with a slightly high idle. (imo the real danger is shifting into L while moving which could over rev the motor.) sprockets aren't too $$ to experiment with. unfortunately treats is out of 25t rears atm.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Eric Migliorino /

Check out JT sprockets. They sell them on Amazon that fit the chappy.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Dirty30 Dillon /

Yeah, if you do the math the CC's are still low. It is more so the increased port sizes that put out power.

I honestly would not be utilizing the hi-lo box at speed. It's a non-synchro, non-mesh gear reduction so even going from lo to hi you stand the risk of catching something and grenading an already hard-to-replace transmission.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Eric Migliorino /

> Hunter Skiff Wrote:

> -------------------------------------------------------

> The break in for my Polini is done. Bike will do mid 30s comfortably

> (13/28 gearing) and will wing to 43mph if you gave it time. Will post an

> update video this weekend. Got a PW80 carb in the mail today, going to

> swap out the stock carb and see what gains are achievable.

>

> Question: Has anyone noticed their factory LB50 speedo is way off? It

> seems accurate under 10mph, but after that it reads really under.

> Cruising this past weekend, 35MPH verified on my gps and on my LB80, and

> my LB50 is reading 27-28. It is possible these old speedometers were

> only calibrated for slow speed?

How did you break in the Polini kit? The manual states not to go over 3/4 throttle the first 500km which is a little over 300miles. Seems sort of excessive but maybe I’m wrong?

Are you getting mid 30’s with the tiny LB50 stock carb??? I couldn’t get my LB50 to work well with the stock LB50 carb, Polini kit and MLM pipe combo. Didn’t spend much time trying to re-jet and time since I had an LB80 carb I knew I put in it.

Let us know how the PW80 carb works out. Does the stock carb/frame cover work with it? Did you need to re-jet? It should come with a 120 main jet. I have an older LB80 carb up-jetted to a 95 jet in mine with the Polini kit. And when I say older style, it’s the LB80 carb that comes stock with a 65 main jet and has the single black plastic float.

Are you keeping the oil pump hooked up or running premix? I was thinking of pairing a PW80 carb with the PW80 oil pump, thinking the gas to oil output we be in line with what the Yamaha engineers originally developed.

Thanks for sharing your upgrades and how they perform.

Eric

Re: The Official Yamaha Chappy (LB50) Thread!!!

> Eric Migliorino Wrote:

> -------------------------------------------------------

> Check out JT sprockets. They sell them on Amazon that fit the chappy.

that's where i grabbed the two front sprockets from (15 and 16t). the full lineup is http://www.jtsprockets.com/catalogue/sprocket/JTF546/

unfortunately jt's lineup for rear http://www.jtsprockets.com/catalogue/sprocket/JTR832/ only goes down to 30t.

Re: The Official Yamaha Chappy (LB50) Thread!!!

Dirty30 Dillon /

Whatever carb you put on there, you will need to rejet.

If you swap cylinders, exhausts, or carbs, you will need to re-meter the pump for correct oil amount.

If anyone desires a PW80 pump, I have one that I would get rid of. But I do not think it bolts to an LB motor

Re: The Official Yamaha Chappy (LB50) Thread!!!

Eric Migliorino /

I was hoping the PW80 oil pump was plug and play. Thought they looked fairly similar but never tried installing one on a LB80 or LB50.

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