Power Fade

[Hedgehog]

Weird things happening.... My guess is its electrical / ignition ....

Tried Original NGK plugs a while back and it ran roughly - especially (if I'm not imagining it) on the right bank of cylinders (as you sit astride the bike).

Put Iridium's in and was OK.  I did wonder if this indicated an underlying weakness somewhere...as the Iridiums need less juice to work.... but left it at that.

Then today, on an 80 mile run, I had a partial cut out of power that seemed to fade in and out - two episodes of a few minutes each.


Pulled up at a junction and the bike sounded a bit rough and had much reduced power (to me it sounded like a triple - only one bank of cylinders firing) Again I suspected the right bank...... as the left side was the only one that seemed to be making a noise... I got going and overtook and it was like riding something with the same weight but only half the power. After a couple of minutes it was OK and she was back to her rip-snorting ways...

Was worrying though....


Before I book it into the local workshop has anyone any ideas...?

I'm thinking right coil or leads...

I did take out a couple of plugs (one each side) and noticed that neither had an especially strong spark (small pinkish spark). gaps are OK.

I also noticed that, for the first time, when I switched off the running lights the tick over increased... it usually don't make any difference...

Don't expect its related but the timing belts were replaced a couple of months or so back.


Huh??? ??? ??? ??? ???

Any ideas welcome..


Thanks

HH

[GJS]

Weird things happening.... My guess is its electrical / ignition ....

I also noticed that, for the first time, when I switched off the running lights the tick over increased... it usually don't make any difference

I'd suspect the same things you are.
The fact that reducing the electrical load elsewhere helps improve the situation would indicate this.

PinWall often has these bits for cheap.

Good luck.

Glenn

[Patrick]

A couple fellas have recently found loose primary lead coil connections, but, each coil fires 2 cylinders.. In that, coil 1 fires #1 and #2 cyl, coil 2 fires #3 and #4 cyl, coil 3 fires #5 and #6... So that kinda eliminates an electrical issue with right or left banks..
But, such an issue could certainly cause a misfire on the 2 related cylinders..
To me, your problem sounds more like a fuel delivery issue such as vacuum or petcock problems..
This problem didn't start right the timing belts replacement did it ?? It still wouldn't hurt to check the valve/cam timing just to make sure the belts were installed correctly..

[gordonv]

I would suggest both suggestions made by Patrick.

When you notice it not running properly, feel the exhaust (careful of burns) for how hot the pipes are, to identify which ones may not be firing completly.

[Crashgordon74]

I had a similar problem last October. It seemed that the whole right bank of cylinders weren't firing. The exhaust on that side was barely warm. Anyway before I could check it further I just put it away for the winter. So it was stored for a little over 6 months with Seafoam in the tank and I had drained the carbs. When I fired it up this weekend it ran like crap. I poured more Seafoam in the tank and took it for a nice long ride. So after 200 miles in two days it is running much better. My plan is to run a tank of Techron and a tank of Berryman's B-12 through the system. Also last winter I removed the plugs and ALL were fouled- carbon, oily and wet. Not sure what caused this to happen. Bad gas??? Anyway before you start taking things apart run some fuel system cleaner several times through the bike. Can't hurt. Sometimes it's the simple things!! 

                                                                     Crash

[Hedgehog]

Thanks guys - very helpful.


Hedgehog

[Ricky-D]

Sounds like something as simple as a bad battery!

***

[Valkpilot]

Sounds like something as simple as a bad battery!

***

Ricky-D, if the alternator is working properly, how would a bad battery cause the symptoms?  I suppose a battery with a failed cell could be dragging down the alternator, but I'd expect starting problems if the charging system is breaking down.

I'm inclined to agree with Patrick that it is fuel-delivery related.

[JaysGone]

PinWall has plenty of used coils.
Im not saying we have a same or even similar problem.
I bought a set of used coils for 29$$ thinking mine was starting to go bad as I had no spark in #6.
Then in number 4.
The exhaust was cold on both manifolds and no power.
Turned out to be of all things bad fuel float valve seats.
Pouring fuel into the cylinders and keeping them in a constant flooded condition.
I ended up having to buy a used set of carbs.
You can buy the float valve pin but if the seats bad or the float itself.
The carbs gotta go.
No replacements available from Honda that I could find anymore.

[ryord]

Hello, I had a similar problem and found the problem to be a plug wire, I bought used coils and plug wires of of Ebay for around 30.00 and cleaned and the replaced 3 and 4, I knew they where not firing because I used a timing light to check them. The problem was intermittent but was pretty consistent when I put the bike away for a day until I got the used parts. I pulled the 3-4 wires off the used coils I just bought and installed them, fired the bike up with the tank off and it ran as it should, has been good ever since. I also went with a Golan petcock and Pingle inline filter. check you wires.

[Ricky-D]

I wonder if an explanation of "tick over" might help is assaying the problem.

***

[BonS]

This is one my favorite tools to check for spark. No wire piercing or fooling around with disassembly of any kind. Simply place it on a plug wire and see a neon flash for each pulse. It's easy to see a misfire or no-fire condition. Cheap, portable and fast diagnostic tool. It's a Lisle LIS19380 spark indicator. I've had one in my tool box for over 40 years. It works best out of direct sunlight but you can shade it with your hand. No batteries required. ~$5

[JaysGone]

This is one my favorite tools to check for spark. No wire piercing or fooling around with disassembly of any kind. Simply place it on a plug wire and see a neon flash for each pulse. It's easy to see a misfire or no-fire condition. Cheap, portable and fast diagnostic tool. It's a Lisle LIS19380 spark indicator. I've had one in my tool box for over 40 years. It works best out of direct sunlight but you can shade it with your hand. No batteries required. ~$5

You mean it works better then licking your finger tip and sticking it in the spark plug cap??
Well Ill be dammed a fluresent light is you need.
Ill have to try that next time around.

[Hedgehog]

Thanks for the help guys!

PS 'tick over ' is English for 'Idle'!!!

 

[Madmike]

If this problem is just on one bank then most likely it is fuel availability or delivery related rather than ignition. 

Infra red heat guns can be had fairly cheap now and are an excellent tool to help find things like cold cylinder and coolant flow problems.  I have had a timing light that has an inductive pickup since forever and use it as a quick indicator to see if a plug is trying to fire  - if there is no current flow in the plug wire the light doesn't flash.

 

[Ricky-D]

I am completely serious about the problem being related to a bad battery.

It's normal for a denial regarding the battery being the problem and yet,  still can be easily checked by using a known good battery.

Go tell!

***

[MP]

I am completely serious about the problem being related to a bad battery.

It's normal for a denial regarding the battery being the problem and yet,  still can be easily checked by using a known good battery.

Go tell!

***

Agreed.  It may or may not be the problem, but it could be.  And, it is an easy and cheap check.  Valks require lots of current, and bad batteries cause a LOT of problems.

MP

[Hedgehog]

New battery on order, also new wires.,..


Thanks for the advice.

HH