Unable to get Roadrunner 300 started (FIXED) By justincrediblem (Read 962 times)

[justincrediblem]

I have a Sunny Roadrunner 300 MC_D300tkb. I had 365 miles on it when she lost power and the engine died. I couldn't get her started back up until I sprayed a little bit of starting fluid into the carb. She would only run at half throttle and would not idle. It was running pretty rough too. I was thinking it was a dirty jet in the carburetor. I did have a spark but it looked weak and was a reddish color and not blueish like it should be. I even changed the spark plug. So I took the trike to a local scooter repair shop and the mechanic said I had a bad CDI. I stopped by the repair shop and he tried cranking the trike for me and said the timing is off and I needed a new CDI. I requested he clean the carburetor and he told me a couple days later he got the trike ideling but I still needed a new CDI. Sunny Motors are way too slow at sending the new warrenty CDI so I just went and picked up the trike from the repair shop. It seemed like it was vibrating more than usual so I thought it might have been running rough because of the timing issue. After about 5 miles of test driving it she died again after going over a bump in the road. I checked the spark again and it still had the same weak, reddish looking spark. After several attempts I finally just went and bought a couple of brand new spark plugs. The spark plug that was in it had only about 6 miles on it. But anyway, after changing the spark plug she started right up but died about 7 seconds later. I checked the spark again and it was weak, reddish. Put spark plug back in and started right up but died about 5 seconds later. Checked the spark again and now I don't have a fire/spark what so ever. After 2 weeks Sunny finally sent a new CDI but it is the wrong one! The new CDI has only 6 pins while the stocked CDI is a 8 pin :\

I just decided to BUY a new CDI and it should be here tomorrow. If its not a CDI problem then I will try a new ignition coil.
I have looked for loose wires but can;t find any. I find it strange though that she died as soon as I went over a bump. I also checked the carb and do not notice any missing hoses.

Any suggestions so I can get this trike back on the road asap? I only got about 3 weeks of ride time on her with a total of 370 miles.

Jason

[Alleyoop]

Well going over a bump and dieing out sure appears to be a loose wire someplace. Have you checked the Wires going to the COIL from the CDI. Usually the CDI will work or not work. Did you check the COIL itself and Made sure the BOOT CAP(THE PART THAT GOES ON THE PLUG) is screwed on tight on the COIL wire. The Boot CAPs screw on and off, same thing at the Actual COIL the COIL ITSELF screw onto the COIL WIRE. They work just like a SCREW turn it CLOCKWISE to tighten and Counter Clockwise to take it off.

Have you ever adjusted the CARBS FUEL RATIO mixture? Turn it clockwise until it stops and then turn it COUNTER CLOCKWISE 2 1/2 turns that is usually pretty good setting that allows the motor to run pretty good. You mentioned you cleaned the carb DID YOU ALSO MAKE sure you cleaned out the PILOT JET PASSAGE? There are TINY holes where the fuel gets sucked out right by the BUTTERFLY they are tiny holes and can easly get clogged.
Get a Spray Can of Carb CLEANER they come with a LONG THIN STRAW. Take the PILOT JET OUT and make sure it clear and you can see daylight throught it. THEN take the Spray can and stick the THIN STRAW into the hole where the PILOT JET SCREWS INTO and spray and here is where spray should come out.
Alleyoop

[justincrediblem]

Hey Alleyoop. The repair shop supposedly cleaned the Carb. The bike seemed to be running great after I picked it up from the repair shop. For about 5 miles until the bump in the road. It does souaybend like a loose connection or maybe loose coil wires because of the original weak spark. I think the brand new spark plug just allowed it to have enough spark to start the bike. I'm going by what the mechanic said and concentrating on getting the proper CDI. But I'm now going to price a new ignition coil and try that as well. I found a more local motorcycle shop that will look at it. I just noticed the original scooter repair shop has a F rating on the bbb site so I'm not gonna use them again. Is there any tricks on finding a wire shorting out? I'm not too keen in the electrical dept.
If I find a coil that is under $50 I think I will buy it and try it along with the new CDI in transit. That's if the new CDI doesn't solve the issue itself. Imma keeping my fingers crossed though. I've already got so much extra money into this bike, tag, title, insurance, motorcycle endorsement, and already $120 Carb clean and diagnosis.

[Alleyoop]

Well if it was running good when you picked it up and hit the bump, Check the SPRAK PLUG BOOT ON THE PLUG. If they did not put some SLACK in the COIL wire going to the SPARK PLUG when the SWING ARM moves it pulls on the SPARK PLUG WIRE and it might have popped off. I know it happened to my brother-in law and I had to go and fix it on the side of the road. But As soon As I popped the access panel I saw the problem the BOOT CAP was almost completely out.
Alleyoop

[justincrediblem]

Also, I have not adjusted the fuel ratio. The bike runs good when it ws running. I have checked the coil wires. In fact after the brand new spark plug was installed and the bike started for a few seconds I jiggled the coil wires to see if I could get a better spark and that's when I noticed I didn't have a spark any more. So I'm really thinking it may just be the coil that may be causing the problem.

[Alleyoop]

Did you check the wires connections on the COIL they sometimes are loose on the connecters. Also take the Boot Cap off the PLUG and try to turn it CLOCKWISE on the coil wire it is just a SCREW inside the BOOT CAP that screws into the WIRES INSIDE the COIL WIRE.
If all that is good then wait for the new COIL.

And if it is running good there is NO REASON to mess with the FUEL RATIO SCREW.
Alleyoop

[justincrediblem]

Yes I did check the big wire and the two small wires connected to the coil. I will look into the boot cap further tomorrow.

[justbuggin]

make sure the little spring wire that holds the plug wire on the spark plug is in there you should feel resistance when you push it on the plug

[justincrediblem]

New CDI installed. Still no fire to the spark plug. Upon investigating further into the Spark plug boot, spark plug wire and coil connection, I did not find that it had come loose. I did however notice some wear on the wire going from the spark plug to the coil. The wear damage to the wire was like it was rubbing against something. The damage is barely exposing a little bit of the wire insulation. I can try replacing the coil and coil wire. But I also thought about a possible dirty /rusty stator. Maybe the stator was making a weak spark and now its just dirty enough to not produce a spark? I have no idea how to even get to the stator. I guess if the new ignition coil won't work I will put the trike back into the shop.

[Alleyoop]

If the COIL wire is exposed it will be arching, If it is close to the BOOT then just unscrew the BOOT CAP and cut the wire where it is bad and screw the BOOT CAP back into the wire.
Alleyoop

[justincrediblem]

Just a update. I received a replacement coil and wire and spark plug boot together as a whole. I installed the new replacement coil. The trike started right up! But she sure was running rough. So I took off the new CDI that I installed a few days ago and put the original CDI back on. The trike now runs normal and cranks right up. So the problem was with the coil or coil wire.

[Alleyoop]

Great!! Good to hear your up and riding and enjoying it.
Alleyoop