Re: Loss of Power

CX500 & CX650 Turbo Forum

Loss of Power

shavron 04-10-2008, 6:43 AM
I rode my bike into work. Washed it, dried it off, and ran it until bike was at norm. temp and exhaust was warm. I shut it down then waxed it. 6+ hours later I went to go home. I started it stumbled and had to open throttle to keep it running. Trying to get going a lot of popping and almost no power. I went ¼ mile shut it down, for 20 min. started up same thing. It was a struggle to get going from the start. Would run with RPMs above 5,000 with little power. I could maintain 40 MPH in 2nd gear. 10 miles home it went away and had full power with TURBO.

Here are my thoughts. No fuel system light came on. To me it was like it was not getting enough fuel. The tank was full. The OEM petcock leaks when off and when on can be moved counter clockwise. I’m thinking that the inside if the petcock my have restricted the fuel flow? The Fuel strainer was just checked weeks prior no restrictions, and the cone filter was clean. No rust in the tank that I can see.

What are your thoughts?

Ron
1975 Honda GL1000
1975 Suzuki RE5M
1976 Suzuki RE5A
1981 Honda CBX
1982 Honda CX500 TC
2000 Honda Goldwing A

Re: Loss of Power

chicagorandy 04-10-2008, 7:06 AM
My limited troubleshooting skills always point to whatever was the 'last' thing I did. In your case that would be the washing.

Perhaps pull the sparkplug boots and dry them out. Or in a dark garage, fire it up and see if you detect any pretty blue sparking around the area of the plugs and boots. Water on hot aged plastic can easily cause cracking and even a tiny crack will cause loss of spark to the plug. The symptoms produced will be just what you experienced.

BTDT on my Ural. To the point where I always carry spare plug caps and a length of new copper core ignition wire.

Just a thunk. It really doesn't sound fuel related to me, but I ain't no mechanic ner nuthin' - lol

2003 Ural Tourist - 76,5000kms to date
1982 Honda GL500 Interstate 8220 miles since 05/30/07

"Down the highway of life at smiles per hour"

Re: Loss of Power

shavron 04-10-2008, 7:36 AM
I'll try to see if it is the wires. I did run it right after washing and hand drying it. It ran fine. I ran it until the engin temp was normal, and kept running it until exhaust was warm.

Thanks for the input

Ron
1975 Honda GL1000
1975 Suzuki RE5M
1976 Suzuki RE5A
1981 Honda CBX
1982 Honda CX500 TC
2000 Honda Goldwing A

Re: Loss of Power

chicagorandy 04-10-2008, 8:04 AM
One of the carbs may have ingested some water? I dunno.

If the problem resolved on the ride home and hasn't reappeared it does sound like 'something' got wet and finally dried. It takes very little loss of ignition force to create some interesting side-effects.

The holy trinity of internal combustion is Air-Fuel-Spark and if any of the three are not playing nice with each other bad stuff happens.

2003 Ural Tourist - 76,5000kms to date
1982 Honda GL500 Interstate 8220 miles since 05/30/07

"Down the highway of life at smiles per hour"

Re: Loss of Power

CXTURBOBOOST 04-10-2008, 3:55 PM
No carbs on a turbo baby....

Check the plugs...
No fuel system light? That's odd. Sounds like ignition...

Pete

Re: Loss of Power

shavron 04-10-2008, 7:06 PM
I think you guys may be right. The popping sound was most likely unburned fuel igniting in the exhaust system.
It just didn’t make sense that it was OK after it was sprayed down. It ran fine and was heated up, and then sat for six hours.
I guess that is the value in getting another point of view.

Ron

Ron
1975 Honda GL1000
1975 Suzuki RE5M
1976 Suzuki RE5A
1981 Honda CBX
1982 Honda CX500 TC
2000 Honda Goldwing A

Re: Loss of Power

Don in Oz 04-10-2008, 8:11 PM
Ron, Check the drain-holes that run from the bottom of the spark-plug wells to the outside of the head - it's a favourite place for wasps to build their nests.

Re: Loss of Power

Randall-in-Mpls 04-10-2008, 10:04 PM
There was a thread not too long ago about coils shorting on the underside of the fuel tank when riding in the rain. Could be a possibility here too, depending where you sprayed. The solution was to place a piece of inner tube over the coils before reinstalling the tank.

R

'78 CX500 - The Black Maggot

CX500 Factory Service Manual
1978 CX500 Parts Manual

Re: Loss of Power

shavron 04-11-2008, 8:29 AM
I checked the spark plug drain holes like Don from Oz suggested. I found dried and caked up dirt clogging the hole on the left side. I took pictures ,but don’t know how to get them on the forum.

Ron
1975 Honda GL1000
1975 Suzuki RE5M
1976 Suzuki RE5A
1981 Honda CBX
1982 Honda CX500 TC
2000 Honda Goldwing A

Re: Loss of Power

chicagorandy 04-11-2008, 8:35 AM
I use Internet Explorer almost always but found that I needed to use Firefox instead and then pics posted fine.

I dunno why, I don't know nuthin' 'bout birthin' no computers. lol

2003 Ural Tourist - 76,5000kms to date
1982 Honda GL500 Interstate 8220 miles since 05/30/07

"Down the highway of life at smiles per hour"

Re: Loss of Power

HomerRod 04-13-2008, 10:21 AM
I concur with the others on this one.
Most definitely sounds like wet ignition components. My dad taught me years ago (in the days of points,condensers,carb's,etc) to always start with the electrical first, then move on to the fuel system. Seems appropriate here, as it seems the water has taken up residence in the plug boots,wires,coils or harness connectors to the coils. I can tell by ear the difference between an ignition miss, and a fuel system miss. Simply remove the caps from the plugs, the wire from the coil, and the two wires from the each coil and blow dry with air (if you don't have compressed air, shake it out good, or buy a can of air at a computer/electronic store). That should do it. Make sure you check the harness to the ignition module under the seat, making usre that the wires are dry. If that does NOT solve the problem, then make sure your air filter did not get soaked and no standing water in the intake pipe from the air filter to the turbo. If this was the case, you would probably see some steam out of the pipe. I don't think the fuel injection system is affected here, since its a pressurized system. If you get stuck, post again and we will move on to some other items.
As always: YOU CAN DO THIS...............

Re: Loss of Power

Don in Oz 04-13-2008, 4:59 PM

Cleaning the mud or wasp-nest out of those drain holes and blow-drying the sparkplug wells (with the plugs in, of course) is a must for ALL CX/GL owners at least annually.

Before you even think of removing a spark-plug at ANY time, you should blow the well clean with compressed air.

If you go to a bike shop, and the mechanic doesn't blow the spark-plug well clean with compressed air before he removes a plug, then find another bike shop and mechanic for your succeeding maintenance visits - the first guy is NOT worth paying, as he doesn't take enough care.

Re: Loss of Power

Anonymous 06-10-2008, 6:25 AM

I had the exact same thing happen to me last summer. First I thought it was the spark plugs, as it seemed only one of my two cylendars was firing, then I thought it was the oil or the fuel (flushed the gas system, cleaned it out with sea foam, oil changed) still only getting half power. Finally I pulled out the air filter and noticed it was quite dirty, so I pulled it out and tried running for a bit without it. Almost instantly I was firing properly again. Remember, that gas is not the most important fuel used in an engine, AIR is. So I have a good feeling that replacing or cleaning your air filter should do the trick.

Re: Loss of Power

BobD 07-07-2008, 1:29 PM
The petrol tap on my CX500T also leaks in the off position. Has anyone ever taken one of these apart and tried to repair it? Ihave wondered whether there is an obstruction in the fuel flow for my bike (see message posted by BobD 7th July) but then it would always be a problem, not just when it is hot.

Bob D

STX1300 Pan European
CX500 Turbo
Francis Barnett Cruiser 89 (4T engine)
Ariel Leader