Dong Fang DF 250 RTB Bobber Information

[Goodbar]

Hey, so let me ask you. Is the headlight a 5 wire config or a 3 wire config? I got a new headlight to install but it is a 5 wire harness in an H4 which means re-wiring. But, if it's a 3 then I may just use the new light housing and retro fitting a proper light for our harness rating

I haven’t dug into any of the wiring and that’s Not a strong suit here either, but I would do the following to just understand the head light. Get a circuit tester with the light and sharp prong.
I have no direct knowledge of these mods but will throw what I plan on doing to trouble shoot the Mod.

Remove Tank then...
1 Turn the key on and get juice flowing in the wires
2 Trace and Unplug the Headlight harness under the tank
3 Look for the ground they are using for the harness on the rear side of the plug, I believe it’s the ground that’s faulty.
Find the green wire that goes nowhere it just terminates, I believe it was originally used for that European on off switch that is disconnected for the US market.
4 Do a jump from the ground wire from the terminated green to the green on the headlight wire. It grounds the Headlight properly so it doesn’t go thru the voltage relay that messes up the voltage.
5Then re-plug the harness back together. so you will have 2 grounds now and that shouldn’t matter. Or the fluctuating ground wire can be snipped and capped off

Skulworkz As far as the 5 wire to 3 wire change over to the H4 socket should be simple. The extra 2 wires the bike now has are for the small light bulb that comes on before you start the bike as far as I know and come on with the ignition key. simply don’t use those two and cap off.
Again this is my plan and I may be 100 percent wrong but I believe I am correct. I have a new H4 socket I am going to use and it has 3 wires only.

- Here is a Past Posts not sure who’s it was

Dimming headlight problem, really easy to unplug the blue and white wire from the dark green wire and plug it into the other blue and white wire like it should have been in the first place. now my light switch works and my lights don't dim

Sylvania H5006 fits DF 250 RTB sealed Beam Don’t put the Glass back no need Just install the retainer ring back on

Reporon Posted: he solved his light issue by running a wire from the blue and white wires in the headlight to an unused wire in the fake oil box. He thinks it was a problem with the resistor that keeps the headlight from turning on until you actually start the engine. It seems kind of goofy to me how they have that small bulb that comes on when the key is in the "ON" position but then the headlight actually comes on when you start the bike. Why not just have the headlight come on when you turn the key. Regardless, if running a wire from the from the high and low beam wires works


Headlight dimming issue resolved!!! After checking everything out with a friend who has a good knowledge of electrics it is confirmed as reported by Reporon that there is a blue wire with white stripe underneath the left side of the gas tank that connects to a dark green wire. It is the only single wire to single wire connection underneath the tank. For some reason as you rev the engine the voltage actually drops from the dark green wire. SOLUTION: Disconnect the wires, cap the green wire and connect the blue wire with white stripe to one of the black wires which are usually a constant 12V (backwards from the black ground we are used to). Now the headlight comes on with the ignition switch and the headlight gets brighter with the engine RPM's and maintains a constant brightness. Also happy to report that there has been no battery problems wiring the headlight that way

One can either do the Mod in the fake oil tank as above but I guess I would feel a need to start at the stuff under the tank. Hope any of this helps if not the reposts of what others did might .

[Goodbar]

Hello all,

I'm currently conducting the break-in on my D250RTB, and I'm having an issue I hope you all may be able to help with.

I'm having issues getting the bike to shift into neutral after coming to a stop, and during riding I am sometimes unable to shift up past 2nd gear. It sometimes won't shift down into first at a stop as well. I've also noticed that the neutral light sometimes comes on incorrectly, while the bike is still actually in gear. The whole situation is keeping me from riding it anywhere but traffic-free sideroads. The clutch cable pulls in easily, but the shift lever gets stuck and won't shift gears. Rolling the bike forward/backwards with the clutch in seems to help correct the issue. Any ideas, suggestions or similar experiences?

Thanks all for your help.

Woody: sounds like your clutch is not fully disengaging. Look at the lever on the engine housing where the clutch cable goes to and see if you can move the lever in more. If you can just adjust the cable so the lever on the engine is fully in the
disengauged position. Other wise your sync transmission may not be syncing correctly.
pull clutch in and count to two before shifting up or down. dont force it
a Check your oil level with Dip stick not screwed in ( low oil could cause this)
b Change Crank case oil with new 10w 40 wet clutch oil
c neutral lite on these is inaccurate at best and finding neutral is a bit tricky and takes a light touch. I never trust a dummy light on anything
d Let it break in further it should get better.
e Your shift rod may be out of adjustment or bent. adjust it a small amount and take it for a spin, if worse adjust it the other way, just a bit at a time 1/4 turn and do not tighten the lock nut gently each time.
Hope this helps! Should be a simple tweak Woody

[freezerboy]

if i understand you correctly goodbar you feel the reason that the switch does not function properly may be a bad ground or faulty connection. Since every bike has the same issue with the light only on low beam, my feelings are that these were wired differently to meet some US import spec. My blue/white wire that does come from the switch has been terminated differently then the earlier posts. When other people simply connect the cut blue/white wire the problem disappears, meaning the switch functions correctly and the headlight does not vary in brightness in relation to the engines rpm. just a thought..........when you had completed your under tank work on you and your buddies bikes i figured you had all of this sorted out. LOL

[Goodbar]

if i understand you correctly goodbar you feel the reason that the switch does not function properly may be a bad ground or faulty connection. Since every bike has the same issue with the light only on low beam, my feelings are that these were wired differently to meet some US import spec. My blue/white wire that does come from the switch has been terminated differently then the earlier posts. When other people simply connect the cut blue/white wire the problem disappears, meaning the switch functions correctly and the headlight does not vary in brightness in relation to the engines rpm. just a thought..........when you had completed your under tank work on you and your buddies bikes i figured you had all of this sorted out. LOL

No actually I am saying the switch on the right was just not used for US bikes and they rewired it bad for the US market to make our main headlite bulb come on when the bike is started. So instead of giving the Headlite a good ground they gave it a ground thru a relay. So just jump a solid ground wire from another source under the tank to the ground wire for the headlite so it does not dim. I am sorry about the confusion its hard to find the words to communicate the fix. We ran out of time on his bike to do the dimming headlite issue on his as he was just so relieved we got all his other electrical issues sorted out he didnt care about his dim low beam. I would just forget about trying to get the now dead switch working as in reality you should never drive without your headlite anyhow day or night!!!!! Just get that headlite a solid ground from one of the many other ground wires under the tank by means of a properly wired ground and your dimming low beam should go away. I will do this soon. just be safe and use good connectors and heat shrink tubing. keep us updated.

[Goodbar]

They may of made a wiring mod at some point so your bike is a bit different but the principle of getting your headlite a solid un-relayed ground is still valid as far as I understand the issue. At my age that sometimes is only for a few minutes

[freezerboy]

I intend to have the switch work properly, high, low and side marker lights even if I have to rewire it completely. I can't believe its that way given some states require inspection that includes high/low beam function to pass. The switch functionality is most important to me and as soon as I get it worked out I will post whatever works.

[Crelow]

Today on the way to the dentist I happend to see another Df250rtb riding down the road. It was
Gloss black with a young kid riding it. Now I have to wait and see if he starts to read this forum.

[Bob form NV]

OK I dumped my oil today (the synthetic stuff) had all of 6 miles on it, and cleaned the oil screen which had 2 small flecks of black in it. Even after this short time the oil was discolored and did show a frothy silver. Blinker lights were not working again so I pulled the tank and checked for loose connections. Everything was looking good there. All the wiring showed continuity, so I bang the flasher about a bit and it started working again. Then off, then bang, then on, dang bang screw this, you get the picture. To relieve my angressions I took the bike out for a spin. If the blinkers quit I'd just reach down and bang the oil can a couple of times and on they'd come on. Decided to push it a bit and it cut out serious at above half throttle. Don't know what that was all about but at 0 to 1/4 it has plenty of torque and I whistle up to forth gear while keeping it under 40. Hoping it will get better with age and adjustment.

My DF is the new model and I found some big differences.

1) The tank is fastened with four machine bolts attached to two taped and threaded solid metal round bars, front and back, that have been welded into the frame. Rubber bushings and washers that limit the bolts squeeze and isolate vibration to the tank.

2) The light switch is a two position switch that comes on when when the ignition switch is actuated and switches low or high via that switch. There ia also a separate toggle switch that flashes the high beams.

3) The tail lights are mounted lower to the frame on welded tabs.

4) The fuel valve selector is three position with an 8 oz reserve.

I think the bikes are selling and the manufacturer is listening to demand, kind of what we used to do here.

I found this information on break in and I like it.

Enjoy

New or Rebuilt Engine Break-in Procedure
A recommended engine break-in procedure.
This is a summation of many articles on the subject found on the internet. Some of the information is from MOTORCYCLIST Feb. 1991, titled GIVE IT A BREAK-IN (How to make your bike run stronger and live longer), and some is from a Textron Lycoming "Key Reprint" article.
The first few hundred miles of a new engine's life have a major impact on how strongly that engine will perform, how much oil it will consume and how long it will last. The main purpose of break-in is to seat the compression rings to the cylinder walls. We are talking about the physical mating of the engine's piston rings to it's corresponding cylinder wall. That is, we want to physically wear the new piston rings into the cylinder wall until a compatible seal between the two is achieved.
Proper engine break in will produce an engine that achieves maximum power output with the least amount of oil consumption due to the fact that the piston rings have seated properly to the cylinder wall. When the piston rings are broken in or seated, they do not allow combustion gases to escape the combustion chamber past the piston rings into the crankcase section of the engine. This lack of "blow-by" keeps your engine running cleaner and cooler by preventing hot combustion gases and by-products from entering the crankcase section of the engine. Excessive "blow-by" will cause the crankcase section of the engine to become pressurized and contaminated with combustion gases, which in turn will force normal oil vapors out of the engine's breather, causing the engine to consume excessive amounts of oil.
In addition to sealing combustion gases in the combustion chamber, piston rings must also manage the amount of oil present on the cylinder walls for lubrication. If the rings do not seat properly, they cannot perform this function and will allow excessive amounts of oil to accumulate on the cylinder wall surfaces. This oil is burned each and every time the cylinder fires. The burning of this oil, coupled with "blow-by" induced engine breathing, are reasons that an engine that hasn't been broken in will consume more than its share of oil.
When a cylinder is new or overhauled the surface of it's walls are honed with abrasive stones to produce a rough surface that will help wear the piston rings in. This roughing up of the surface is known as "cross-hatching". A cylinder wall that has been properly "cross hatched" has a series of minute peaks and valleys cut into its surface. The face or portion of the piston ring that interfaces with the cross hatched cylinder wall is tapered to allow only a small portion of the ring to contact the honed cylinder wall. When the engine is operated, the tapered portion of the face of the piston ring rubs against the coarse surface of the cylinder wall causing wear on both objects.
Each tiny groove acts as the oil reservoir holding oil up to the top level of the groove where it then spreads over the peak surface. The piston ring must travel up and down over this grooved surface, and must "hydroplane" on the oil film retained by the grooves. Otherwise, the ring would make metal-to-metal contact with the cylinder wall and the cylinder would quickly wear out.

However the ring will only ride on this film of oil if there is sufficient surface area to support the ring on the oil. When the cylinders are freshly honed the peaks are sharp with little surface area. Our goal when seating the rings on new steel cylinders is to flatten out these peaks to give more surface area to support the rings, while leaving the bottom of the groove intact to hold enough oil to keep the surface of the cylinder wet with oil. See illustration. At the point where the top of the peaks produced by the honing operation become smooth and the tapered portion of the piston ring wears flat break in has occurred.
When the engine is operating, a force known as Break Mean Effective Pressure or B.M.E.P is generated within the combustion chamber. B.M.E.P. is the resultant force produced from the controlled burning of the fuel air mixture that the engine runs on. The higher the power setting the engine is running at, the higher the B.M.E.P. is and conversely as the power setting is lowered the B.M.E.P. becomes less.
B.M.E.P is an important part of the break in process. When the engine is running, B.M.E.P. is present in the cylinder behind the piston rings and it's force pushes the piston ring outward against the coarse honed cylinder wall. Piston rings are designed to take advantage of the pressure and us it to push the rings out against the cylinder wall. Therefore, as pressure builds during the compression stroke, the rings are pushed harder against the cylinder wall which aids in seating the rings.
The higher the B.M.E.P, the harder the piston ring is pushed against the wall. The surface temperature at the piston ring face and cylinder wall interface will be greater with high B.M.E.P. than with low B.M.E.P. This is because we are pushing the ring harder against the rough cylinder wall surface causing high amounts of friction and thus heat. The primary deterrent of break in is this heat. Allowing to much heat to build up at the ring to cylinder wall interface will cause the lubricating oil that is present to break down and glaze the cylinder wall surface. This glaze will prevent any further seating of the piston rings. If glazing is allowed to happen break in will never occur. Also, if too little pressure (throttle) is used during the break-in period glazing will also occur.
Most people seem to operate on the philosophy that they can best get their money's worth from any mechanical device by treating it with great care. This is probably true, but in many cases it is necessary to interpret what great care really means. This is particularly applicable when considering the break-in of a modern, reciprocating engine.
For those who still think that running the engine hard during break-in falls into the category of cruel and unusual punishment, there is one more argument for using high power loading for short periods (to avoid excessive heat) during the break-in. The use of low power settings does not expand the piston rings enough, and a film of oil is left on the cylinder walls. The high temperatures in the combustion chamber will oxidize this oil film so that it creates glazing of the cylinder walls. When this happens, the ring break-in process stops, and excessive oil consumption frequently occurs. The bad news is that extensive glazing can only be corrected by removing the cylinders and rehoning the walls. This is expensive, and it is an expense that can be avoided by proper break in procedures.
We must achieve a happy medium where we are pushing on the ring hard enough to wear it in but not hard enough to generate enough heat to cause glazing. Once again, if glazing should occur, the only remedy is to remove the effected cylinder, re-hone it and replace the piston rings and start the whole process over again.
We asked four top motorcycle engine builders what they do to ensure peak power output and optimum engine life. Here is a capsulation of their responses.
"If the wrong type of oil is used initially, or the break-in is too easy, rings and cylinders could (read will) glaze and never seal properly. A fresh cylinder wall needs some medium to high engine loading to get the piston rings to seat properly for good compression but make sure you don't lug or overheat the engine. Use high quality, low viscosity oil (Valvoline 30 weight), no synthetics, too slippery. If synthetics are used during initial break in the rings are sure to glaze over.
An engine's initial run should be used to bring oil and coolant (air, oil, and/or water) up to operating temperature only, with little or no load, then shut down and allowed to cool to ambient temperature. This is important. After each run the engine needs to completely cool down to ambient temperature. In Texas, especially in the summer, that's still pretty hot. After a cool down period, start it up again and take the motorcycle for it's fist ride (you hope).
This time give the engine light loads at relatively low rpm and stay out of top gear. Lugging the engine, i.e., low RPM with a lot of throttle (manifold pressure), is more detrimental than high rpm. Another key is too constantly vary engine load during the entire break-in period. A constant load is not ideal for breaking in bearing tolerances. This second run should last only 10-15 minutes before another complete cool down.
The third run should see slightly higher rpm with light to medium power loading using short bursts of acceleration to help seat the rings. Again 10-15 minutes of running should do it and again avoid top gear. A forth run should consist of light to medium engine loads with a few more bursts of medium-high rpm, and lasting just 10-15 minutes varying the engine load and again avoiding top gear. Next while the engine is still warm drain the oil and change the filter. This gets out the new metal particles that are being worn away. Most of the metal particles will break away within the first 50 -75 miles. To ensure the rings seat well, use the same high quality oil and don't be shy about short duration high rpm blasts through the lower gears after the oil has been changed.
A few more 15-20 minute sessions should be used to work up to the engine's redline gradually increasing the engine loads. After some definite hard running and 250-500 miles it's a good idea to check the valves. After 500 miles re-torqueing the head is suggested. Switch to synthetic oil but not before 500-1500 miles. Most of the engine experts warned of the danger of breaking in the engine too easily and ending up with an engine that will always run slow whether it is from tight tolerances, inadequate ring seal or carbon buildup. Engine load is more detrimental than rpm because of the head created internally, so avoid lugging the engine but rev it freely especially in the lower gears. Basically, be sure not to get it too hot but be sure to seat the rings properly.
So that's it, sure a lot different than keeping under 4000 rpm for 500 miles then under 5000 rpm for 1000 miles. Maybe bike manufacturers are being super cautious at the expense of your motor's performance? I think that they take the cautious route that works over time (1000 miles, or about 20 hours of break in) versus a faster route that can be more easily screwed up."

[Goodbar]

I intend to have the switch work properly, high, low and side marker lights even if I have to rewire it completely. I can't believe its that way given some states require inspection that includes high/low beam function to pass. The switch functionality is most important to me and as soon as I get it worked out I will post whatever works.

Freezer Boy For sure you want the headlite high low beam working, I am only refering to the ON Off Switch on the right side that is not wired to anything when the bikes are recieved, its by the starter button. That switch was meant to turn the entire headlite off. Thats the one I wouldnt recommend hooking up as one could forget to turn it on and get a ticket or worse get hit from a car. One for sure wants to fix the terrible dimming issue though. If You want that switch to work than I believe you need to change the wires in the Oil Tank. More than one way to accomplish it.

Bob, There has to be a connector in the FAUX oil tank that has a bad contact or a broken wire inside the insulation. ( OMG the wire is very thin gauge like a 20 gauge) The connectors on these bikes are aluiminum and may appear tight but are not contacting each other. A gentle squeeze on each connector to pinch them all might get rid of the annoying intermittent Turn signal problem.
Dont pich the bullet Female one the wrong way as it is only a 3/4 loop style type that will actually open up and be looser just examine one up close and you will see what I mean. You may want to pinch the male side of each on a tiny bit to widen it a bit.
You should pull your plug Bob and check the color of the plug and see if its black and fouled.
shouldnt sputter out at 40
Mine ran like that also before jet change to a 105 and a new plug because the shop dealer owner was running the bike with the choke always on so it would run and he fouled the plug pretty bad.
But most likley just need a little adjusting to the air mix screw/ They dont adjust em at all at the factory. I wonder if the new bikes like yours have in them for jet numbers as you are the only one in the forum with the brand new model. Most likley the 105 main but who knows....

Oh and when you checked the connectors under the tank did you dig down deep into the harness, as the one on Joe's bike was a white connector that was really burried in there deep and was not visible. Just wondering?

[Bob form NV]

Goodbar, I'll fool with the plug on the flasher some more. I know for a fact that the wiring to the plug is good, tests perfect with the VOM no mater how I bend it around. Positive to ground =no resistance,12 volts, turn switch off= open circuit, 0 volts. turn switch on=closed circuit, 12 volts. The fact the the lights all work but don't flash is a pretty good indication the the flasher is is the culprit. But I'm not sure as it reads a closed circuit all the way around and I'm not sure what it's values are suppose to read. I do know when I have it connected and thump it in the palm of my hand it starts working then flip it around a bit and it will quit. I'll get a new one or two (spare), I mean it's a two bit, I mean 5 buck part.

Will check the spark plug. When I started it this morning I tried your method. Taking note of the choke position. After several tries in the full position it managed to do a couple of turns on it's own. Moved to half choke and started and ran for a second or two. At 1/4 fired and ran for three seconds and quit. One at 0 choke fired and went about the same. Tried again same and brought it to a low rpm by hand for 30 seconds and it idled perfect.

I imagine with how new it is it still needs to just be run. Shifts and goes into n great.

What spark plug is the best?

OH, my harness is way different than those I've seen pictured.

Part 1 is 3 white plugs under the tank with plastic loom up to about an inch on either side of it with a few open wires that I'm sure are for the other option street bikes that they offer.

Part 2 hangs just under the tank and is somewhat accessible once you pull back the plastic sheath that half ass covers it. It has 5 plugs 4 white 1 red and more open connection that I am again sure go to optional equipment.

The plug for the blinker circuit was easy to identify, soon as you unplugged it the maker lights went out.

Everything checked good but I am going to do a di-grease and wrap job eventually.

Thanks