aintnothang
New Member
On my lifan swap I'm trying to hook up my regulator. Looking at different pictures has me confused, do I hook the green non ground wire to the white wire from the motor or to the old rectifier green?
Lifan swap almost there... Regulator help
- Thread starter aintnothang
- Start date
theraymondguy
Well-Known Member
The green wire with the bullet connector goes to the white from the new engine's magneto harness. The original 6V regulator is now an unlikely paperweight - remove it if you wish.
aintnothang
New Member
Does the yellow wire from the Lifan engine stator need to splice into the headlight yellow wire from the og harness as well? Because I have the yellow from engine not going to anything. I was under the impression that the battery ran the lights and it wasnt needed.
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JPardue
Active Member
You might want to look at how its done on this diagram:
http://www.parduebrothers.com/ct70/ct70withclonepowerwiringdiagram.pdf
Check the jumper at the Ignition Switch: Yellow to headlight powers up from DC right there. theraymondguy is telling you the right advice
Jon
http://www.parduebrothers.com/ct70/ct70withclonepowerwiringdiagram.pdf
Check the jumper at the Ignition Switch: Yellow to headlight powers up from DC right there. theraymondguy is telling you the right advice
Jon
aintnothang
New Member
So I need to wire in a jumper basically?
67Motorcat
Member
Yes kinda...just splice in the yellow wire from the rectifier plug in harness to the yellow wire on the main harness at the most convenient place.
This would be an ideal place to use a "scotchlock" connector.Just be sure to use the 3M brand.
Attachments
JPardue
Active Member
My wiring diagram is different and opposite the advice given by 67Motorcat, yet both solutions light the headlight.
67Motorcat describes an AC-powered headlight, mine shows a DC powered headlight.
Difference: the AC headlight will be dim at idle and low engine RPM.
The Dc headlight will be bright at idle and all RPM's, if you run a battery as my diagram shows.
67Motorcat is describing how to tap the Yellow AC power line from the Lifan, which also feeds AC to the Lifan regulator, to power the headlight from AC. Downside, the headlight is dim at idle and low RPM.
In my diagram, you convert the headlight to DC (battery) using a jumper to the headlight switch. Works well with Lifan engines when using a matching Lifan Voltage regulator and a small 12 Volt battery. Upside, the headlight is bright all the time.
67Motorcat describes an AC-powered headlight, mine shows a DC powered headlight.
Difference: the AC headlight will be dim at idle and low engine RPM.
The Dc headlight will be bright at idle and all RPM's, if you run a battery as my diagram shows.
67Motorcat is describing how to tap the Yellow AC power line from the Lifan, which also feeds AC to the Lifan regulator, to power the headlight from AC. Downside, the headlight is dim at idle and low RPM.
In my diagram, you convert the headlight to DC (battery) using a jumper to the headlight switch. Works well with Lifan engines when using a matching Lifan Voltage regulator and a small 12 Volt battery. Upside, the headlight is bright all the time.
aintnothang
New Member
So I got the regulator spliced in. I'm still unsure about the yellow wire from the stator it's not hooked up to anything. Thank you for your help.
JPardue
Active Member
No matter how you power the headlight, here's the deal on the Yellow stator wire:
Your Lifan engine has two different stators. One is for powering the ignition (Black/Red). We are not speaking of that stator.
The stator in question is for powering a regulator. Its for battery charging and lights. The stator has two wires (Yellow and ... not sure if yours has a White?) that output balanced AC power designed to feed a matching Lifan Voltage regulator. Balanced means the same amount of AC power is available on both wires, and neither wire has anything to do with Ground. The regulator Ground connection, is the first place that AC power connects to Ground. Lifan's intent is that you will power up their matching rectifier unit, which has 4 wires, with the balanced AC power coming from the stator, and no lights will be powered from AC power. This is very smart, because then all the light bulbs are protected from power spikes, and also remain bright all the time.
Lifan copied this setup from the later Honda Spree other small Hondas, by the way. Ditto the CDI ignition, among other things copied. Its why they call it a "clone". The CT70 is way older than the Spree, and so the wiring system is quite different. You are putting a way modern engine into an antique.
This is not my opinion, or conjecture. Its a fact derived from studying every available wiring diagram from Honda to ZongShen, and from practical experience building and helping 100's of people rewire old Hondas with a new engine. The people that make these new engines are not assisting anyone about these facts on paper or in manuals, but their designs are obvious to the trained eye.
CONFUSING: Honda uses a Yellow wire from the stator to power the CT70's headlight, BUT the stator is not a balanced design. It has one part of the stator Grounded, then a Yellow "tap" to power the headlight, HI beam indicator, and tail light. The remaining stator tap (Green on a CT70 K0) powers a 2-wire rectifier, which charges the battery.
NOT CONFUSING: Your Lifan is wired like a newer Honda. Its wired different than your old CT70. So, wire your bike different. Accept the full benefit of having that new engine. Join the club of us that have bright lights at all RPM's. Wire the Lifan stator to the Lifan regulator, which involves connecting the YELLOW wire from the engine, to the regulator. Skip the very tempting T connection into that Lifan Yellow, with the old Honda headlight Yellow. I know, the colors match. Move past that thought. Unwire the Yellow Honda headlight wire, as I show in the very clear diagram offered, at the ignition switch. Install the jumper shown. Wire that Lifan Yellow to the regulator only.
Go look at how clear my Lifan to CT70 wiring diagram is on this. Notice the lack of confusion there. Page 2 and page 4.
Jon Pardue
Florida
Home of the Pardue Brothers
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Adam-NLV
Well-Known Member
I installed a Lifan 110cc on my K0. The yellow wire connects to the main bike harness. It hooks AC power from the lighting coil (magneto) through the IGN switch then straight to the brightness switch and then to the headlight.
That's how I wired my k0 and the lights work well.
JPardue
Active Member
This proves there are two ways to do the Yellow wire.
Adam-NLV is an experienced and skilled person, and his experience with the Lifan Yellow T connection is different than mine.
Jon Pardue
Florida
Home of the Pardue Brothers
Adam-NLV is an experienced and skilled person, and his experience with the Lifan Yellow T connection is different than mine.
Jon Pardue
Florida
Home of the Pardue Brothers
Adam-NLV
Well-Known Member
Thanks Jon.
I never tried wiring it up like your diagram shows. On page II, your showing a jumper from the battery straight to the head light at the back of the ign switch and the C connector on the IGN switch is left unconnected. By jumping the IGN switch like that means your running the HL off the battery on DC.
That's new to me but that will work also.
JPardue
Active Member
Yes Sir, you are correct. The DC headlight was a solution to a whole bunch of people complaining the headlight was dim at idle.
After working on a Lifan street bike and a Honda Spree, the observation was made: the headlight is powered from the battery. Both those bikes had bright lights all the time. Deeper studies (unwinding stators, de-potting regulators) revealed the "balanced" stator design.
Surely appreciate that guys like you and 67Motorcat post what works for you.
Jon Pardue
Florida
Home of the Pardue Brothers
67Motorcat
Member
JPardue
Active Member
Adam-NLV
Well-Known Member
Sorry guys this is a long one
Hey Jon, I do like where your going with wanting to run the headlight on DC. It does have its advantages. For instance, the headlamp will last for years on DC, where as AC with all it’s positive and negative sinusoidal peaks burns them out periodically.
Before we get ahead of ourselves; lets review some of the design details of the late 1960’s Honda CT70 lighting coil & charging circuit.
As you already know, the lighting coil is center tapped in the middle and hooked to ground. S o effectively, we have two coils that are now sectioned off. One half of the coil is then designated for charging the battery and the other half designated for running the headlight.
If you disconnect the side that runs the HL and just hard wired it to the battery, then you have one half of the coil being used for charging the battery and powering the HL , Tail light, Horn & blinkers, while the other side of the coil is not used & left disconnected.
If you were driving on a dark country road, that wouldn’t be a problem but if your driving it in the city, where you start/stop blink while turning, that’s going to be pretty taxing on that circuit and eventually the battery won’t charge fast enough and will die along with all the lights.
You may ask “Well why do some modern bikes run their HL on DC?†Simply put; Full-wave rectification. In the late 60’s when these bikes were being designed, silicon semiconductors (diodes) were extremely expensive, not available for civilian use and probably classified at that time.
So instead of taking 4 Orange tin-can selenium diodes and making a full bridge rectifier from those, (which would have been expensive, cumbersome and power robbing) Honda instead, opted for a single selenium tin-can diode and used that to charge the battery and an UN-rectified circuit (AC) to power the headlight. An ingenious solution! Chalk one up for the Japanese.
So what’s the solution to a dimming headlight in a 6 volt 1970’s technology Trail bike?
Simple; Silicon is cheap now days and so are full bridge rectifiers. Grab two of them (yep it will take two because the lighting coil is center tapped into two coils as discussed previous and as you already know) and full wave rectify both circuits.
The other solution is to accept the fact that old technology has its downside and the HL will dim when the engine’s RPM’s is low.
Once again let me reiterate; It's nice to see someone else interested in this stuff besides me.
Thanks Jon P
Hey Jon, I do like where your going with wanting to run the headlight on DC. It does have its advantages. For instance, the headlamp will last for years on DC, where as AC with all it’s positive and negative sinusoidal peaks burns them out periodically.
Before we get ahead of ourselves; lets review some of the design details of the late 1960’s Honda CT70 lighting coil & charging circuit.
As you already know, the lighting coil is center tapped in the middle and hooked to ground. S o effectively, we have two coils that are now sectioned off. One half of the coil is then designated for charging the battery and the other half designated for running the headlight.
If you disconnect the side that runs the HL and just hard wired it to the battery, then you have one half of the coil being used for charging the battery and powering the HL , Tail light, Horn & blinkers, while the other side of the coil is not used & left disconnected.
If you were driving on a dark country road, that wouldn’t be a problem but if your driving it in the city, where you start/stop blink while turning, that’s going to be pretty taxing on that circuit and eventually the battery won’t charge fast enough and will die along with all the lights.
You may ask “Well why do some modern bikes run their HL on DC?†Simply put; Full-wave rectification. In the late 60’s when these bikes were being designed, silicon semiconductors (diodes) were extremely expensive, not available for civilian use and probably classified at that time.
So instead of taking 4 Orange tin-can selenium diodes and making a full bridge rectifier from those, (which would have been expensive, cumbersome and power robbing) Honda instead, opted for a single selenium tin-can diode and used that to charge the battery and an UN-rectified circuit (AC) to power the headlight. An ingenious solution! Chalk one up for the Japanese.
So what’s the solution to a dimming headlight in a 6 volt 1970’s technology Trail bike?
Simple; Silicon is cheap now days and so are full bridge rectifiers. Grab two of them (yep it will take two because the lighting coil is center tapped into two coils as discussed previous and as you already know) and full wave rectify both circuits.
The other solution is to accept the fact that old technology has its downside and the HL will dim when the engine’s RPM’s is low.
Once again let me reiterate; It's nice to see someone else interested in this stuff besides me.
Thanks Jon P
JPardue
Active Member
First off, thank you for recognizing me as someone who is interested in these bikes. My posts are perhaps too long. The first bike I ever rode with a clutch, was my brother's 1970 CT70H. That was maybe 1973 or so, and I would have been 12 or 13. Been a fan ever since.
Some time ago, several German gentlemen wrote me about their DAX bike mods, so I drew up almost everything you are talking about here...
In those pages, the full wave variant shows the stator ground tap removed.
Omitted: no dual full wave rectifiers. I do not grasp how two full wave rectifiers will do any good if one AC input is ground (chassis) referenced, then the ground output is also ground (chassis) connected. I did not draw up two full wave rectifiers, but will do so if you are interested to see why I don't think that works quite right with just one "ground" connection. You would need a floating ground to get the benefit, which is do-able, but complex. Your thoughts on this matter would be interesting to hear, I might be in for learning something new, or sharing something worthy.
You might like my animated half-wave rectifier and full wave rectifier
Great discussion, many thanks!
Jon Pardue
Florida
Home of the Pardue Brothers
Adam-NLV
Well-Known Member
Here's the circuit.
Do the head light bridge first( B1). Get that one going, that's the easy one. Notice my humps and nodes. On the anode of D4, B1 that's an erased line but it still showed up. The anode of d4 is the neg- to the HL That's a node but it didn't show up.
Get the book: Basic electronics by GROB. bet u can get it on eBay or Amazon real cheap.
THe anode of the diode is the line side not the triangle. You got a learning curve to get through, Use google , it's a great tool for looking up tech stuff.
If you don't have a O scope, I'd suggest you get one. Just voltage measurements aint gonna cut it. I have a Tektronix 2235.
The charging bridge circuit is gonna be the bitch of the bunch (B2). I'll help you w/t grounds but do the HL first.
View attachment 20385
JPardue
Active Member
Time to be polite but direct. There are two oscilloscopes at my bench, a dual trace Tektronix Type 453, and a Sencore PS163. Neither one is needed to comprehend a simple bridge rectifier circuit such as used on bikes. Both 'scopes are used on occasion to analyze waveforms in circuits I design, or to troubleshoot.
If you you observed my animated diagrams, which were linked, those are used by at least one college professor to explain rectifiers to students. Your inference I should pick up a primer on electronics to learn where a rectifier anode is located indicates you are being rude, or maybe you wish to attempt to insult me. Your comments seem negative and immature.
Respectfully, your diagram is incomplete. I drew it just now, and posted it for your review. The floating grounds I mentioned in my earlier post, are shown there to the side of the diagram. Your battery schematic symbol was inverted, but is corrected. Your headlight circuit is perfect, however the battery circuit is lacking important details.
Jon Pardue
Florida
Home of the Pardue Brothers
Adam-NLV
Well-Known Member
I was trying to be helpful not insulting.
By the mere fact that you disconnected the lighting coil and run the entire bike off the charging circuit is a indication that you may want to re-think that design and maybe look over some fundamentals of circuit design.
It's one thing to draw the circuit nice and neat but it's another thing to get things working in the real world. I designed that circuit to point you in a direction that would be a viable avenue to run the HL on DC. You don't appreciate my help, then fine, come up with your own design. I conveyed to work on the B1 first and then tackle the ground issue for the charging circuit. I asked if you had a O scope because I think the voltage could be clipped on the charging circuit but only seen on a scope.
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