RD07A problem

[matijak]

Yesterday, I start the motor normally, a minute of worm up, turn the lights on and go. Nothing uncommon, no strange noises, all perfect... After 2km, the engine starts to cough, lose power and after 100m stops. When I try to start engine, there was no enough power in battery to start the engine, but the lights and all still works. I started to pull the motor back home. On downhill tryed to start the engine, and after 10-20m of starting, it starts to work, not good, it sounds like the engine don't get enough feul, or work with one cylinder. After 200m, the engine stops again. At home, I put the new battery, and after a lot of tryouts, the engine start again, again caughing badly, the throttle response was poor and after 10-15 seconds it stops. Another tryouts was wasting of time. It was late and dark and I left the bike.

What should I try?

Is that the symptoms of the fuel pump malfunction? Clogged gasoline flow? CDI? Rectifier?

Thanks in advance!

[meljordan]

Your fuel pums packed up, you can bypass it for now and just keep your tank full...Do a search for facett fuel pump.....

[BobA]

Do you use the choke ??

A common problem with Africa Twins is the choke cable/mechanism getting stuck.

The problem could also be the fuel pump, as these are troublesome on the Africa Twin. To check, bypass the fuel pump by disconnecting the pipes from the pump and connecting them directly together. You must fill the fuel tank to almost the top, and then gravity will feed the carbs. The fuel pump is only really needed once the fuel in the tank drops below the level of the carburettors.

Let us know how you get on.


Good Luck


Bob

[africa twin boy]

My first thought was the fuel pump, a very common problem. But then your statement " there was no enough power in battery to start the engine "
leads me to believe it is an electrical problem. So the issues are:
1. Battery has loose connections at the terminals.
2. Check all the plugs to the rectifier, sometimes these will burn and corrode.
Look at both the input plug as well as the output plug.
3. The voltage regulator / rectifier may have gone bad. They seem to have a
life of around two or three years.
4. Finally pull the main fuse to check it, and pull the plug on top of the
starter solenoid to see if the terminals are burned.
5. Pull the output side of the fuel pump and crank the bike to make sure you are getting fuel. This will check the pump, shut off valve and fuel at the same time.

In essence your bike stopped because the voltage became too low. This is verified by the failure of the starter to turn the bike over after you came to a stop. I am amazed that putting in a new battery did not fix the problem. A new fresh fully charged battery in essence rules out the entire charging system however. I still think the problem is a burned connector.........
Under the fuel tank above the carbs is a row of plug in connectors. On my bike the plug in connector for the ignition became badly burned . Took me a long time to find it....

[africa twin boy]

Forget the bike problem !! I just notice BobA's avatar. Holy **** !! Is that a real woman or is it photo shopped ?????

[matijak]

Thank you guys for your help.

I forgot to mantion, I bought this RD07A before two weeks and I have only 200km experience on that bike. The previous owner says that bike is perfect... and it looks and sound perfect ...200km. I had RD03 for 4 years, and I travelled on that bike from Serbia to Middle East, across two deserts and back, so I can say that I'm a familliar with AT's. Really, didn't expext so much differences between RD03 and RD07A.

Africa twin boy,

with "Pull the output side of the fuel pump'', did you mean that I should to disconnect the output hose from the pump? ..and, when I crank the engine, if the pump is OK, the fuel should start to flow out??

Few days ago, I put the alluminum plate on my RD07A underneath the regulator/rectifier, which left from my old RD03, to ensure better cooling (on both models the R/R's are the equal dimensions). When I take out the RD07A R/R unit, on bottom side, in the middle, I noticed little cracks on that ''plastic'' surface. I didn't get upset, because the bike works fine before that. My first ride ater that was this 2 km ride, when my AT refuse to go further. Is that cracks can be the sure sympthom of bad R/R?

How to surely check regulator/rectifier? On my old RD03 I had the problem ''with electircity''. I had suspicions about R/R unit, measure relations between 5 contacts and compare the values with user manual, as they suggest for checking R/R. Some values vere wrong, and I replace R/R with brand new original. That didn't solve my problem. On the new R/R values was also out of values given by the honda user manual (in little fusnote was advice to use original Honda measuring multimeter and crap like that). Also, for checking stator, manual suggest to measure Ohm values betweeen contacts from 3 yellow wires from alternator. According to that method, my stator (compleatlly grounded by broken gear teeth who falls betven stator and rotor) was in perfect condition. So, is there any better way to check the R/R?

After all, is it possible that bad R/R kills the fuel pump??

I will check the pump and all the contacts and fuses.

Thanks a lot!

[matijak]

Yes, with the BobA's unit(s), there will be no more weak pumps for sure! Forget about Facets and Touratechs.

[diskow]

I would bet on this:
"A common problem with Africa Twins is the choke cable/mechanism getting stuck."

I had the same problem.
After stripping down choke cable twice and lubricate everything to the needles it finally started to work.
Just before that 3 spark plugs died because i was driving home with this bad explosions. I wasnt counting on spark plugs, but that i saw....
Spark plugs failure

Check:
- choke cables to the end (be careful not to brake plastic screws at the end) - even it it looks fine - lubricate
- before power on check spark plugs if you have spark on each plug.

good luck
report.

[africa twin boy]

Hmmmm......The crack on the back of the R/R usually means the unit is fried. That is exactly what my R/R did when it stop working. Think part of the rectifier inside overheats and causes the plastic to crack. When it goes bad, it goes to high voltage, I think around 17 volts, which over a period will fry everything electrical on the bike. Do not ask me how I know this.....
So it is possible that maybe your fuel pump was weakened, and the failure of the R/R unit kicked it over the edge. LIke I said before , putting in a fresh battery in essences now rules out the entire charging system. Now fill the tank to the very top, this will rule out the fuel pump as the fuel flow to the carbs without the pump as long as the tank is over half way full.
You said before that when the bike stopped the first time, the battery was so dead the bike would not crank over? Only the lights would work?
To check the fuel system, you need to pull the hose from the output side of the fuel pump that goes up to the carbs. You must crank the bike to activate the fuel pump, and see what comes out. That will rule out a blocked fuel filter, or a faulty fuel valve, or a blocked fuel line. Again here in Asia it is a very known problem to have the R/R plugs get burned. A lot of people including me have got rid of the plugs, and simply hardwired them together.
Here....


Here is what happened to my connector plugs for the R/R. As it is a common problem, I think that Honda just did not engineer it properly.
What occurs is that after it gets burned , it will allow some current to pass through but not enough.

[matijak]

Thanks man!