I am stumped!

[Mr. Paul]

My 93 Helix, which is a wonderful machine, has an intermittent problem I cannot seem to get diagnosed. I ride this bike as a commuter so it is ridden practically every day. Sometimes when I start, and other times while I am riding, the scooter will loose about 20% of its power. After a while the power will suddenly come back to 100% and stay that way and sometimes will cut back again.  As I have stated, it is intermittent so there is no pattern to it. It does not seem to run rough. Just loss of power. I have loosened my fuel cap, changed and checked the spark plug, changed the fuel filter, checked the fuel lines, inspected my air filter and "puke tube." It starts easily every time and does not smoke or use oil. The idle is smooth and even.  When it cuts in and out, it is abrupt and very apparent. It will still cruise at speed but when the power is down, it really slows the acceleration and hill climbing. Any ideas anyone? I do not want to start throwing unnecessary parts at this thing.

[tortoise]

One troubleshooting technique is placing an ice pack against the CDI . . to diagnose a potential heat related deficiency.

[scrollderf]

Might want to try the folk on: The Honda Helix Discussion Board
http://www.slonaker.net/helixforum/viewforum.php?f=4

[Mr. Paul]

Might want to try the folk on: The Honda Helix Discussion Board
http://www.slonaker.net/helixforum/viewforum.php?f=4

I just did thanks but this is the best group of folks on the net!

[MJR]

I miss my Helix. Not sure if the something like the carburetor could be an issue or CDI as also suggested.

[CROSSBOLT]

With a carb there is the CDI and auto choke of some kind. Like mentioned by techs smarter than me, I vote for those two. Methinks the ice pack on the CDI is a good start but the auto choke, if by starter type, would be first on my list. An intermittent electrical contact could produce your symptoms.

Karl

[Redk]

Good options presented...

IMO, need more information to diagnose, which is why throwing parts at a problem is frequently the best option compared to prolonged labor.

At what temp/runtime does this occur ?

If it is a heat related problem, an electronic problem could be rearing it's ugly head, or a vacuum leak could be growing.
Especially considering age of the machine...   ( I do have an 87 Helix).

There could be debris floating around in the carb bowl, grit or wear on the CV slide, a brittle or defective gasket affecting vacuum circuits for the CV operation.

The icepak idea is Really kool !  If you only had one handy, could hop off, get inside the box to apply it, and continue the run to see if the prob continued. :-)

I don't see a silver bullet here.
Dreary maintenance and parts replacement is probably on the horizon if it is not accommodating enough to get worse and be easily identified !

Not yet mentioned, it could be float bowl adjustment, or a degenerating spark plug wire.

Best
redk

[CROSSBOLT]

Not this guy, Red!

Karl

[ole two wheels]

As mentioned by red, could be a misfiring plug. Also water in the fuel?? Water can get in the fuel filter, new or old, and form a dam that the fuel cannot pass thru easlily. After engine is shut off, the water drains back enough for the fuel to get thru, until enough vibration causes the water, which is much thicker than gas, to form another blockage. This may not seem logical but I've seen it happen more than once. There is a product, I think it's called HEAT, that will break the water down and cause it to go on thru the filter. Also, Karl's thoughts on fuel tank ventilation could be a factor. All an engine needs to run is fuel, air, and spark at the proper timing, so your problem lies some where in that. Not much help, I know. I wish you luck.The Helix 250 is a fine scooter.Let us know what the verdict is.   

Mac

[Mr. Paul]

Thanks everyone for the responses! There is absolutely no pattern to when the problem occurs. Will look at auto-choke, will pull and service carb and replace float, and tap tap the cdi to test. I have a multi tester so I will go on Youtube to find how I can use the thing to diagnose the electronic items. It will take me a couple of weeks to track it down, life has me real busy these days. As soon as I find the problem, I will let y'all know. Thanks again..Paul

[MJR]

Hopefully it's a quick/simple fix, intermittent problems are a pain especially if you don't have a way to duplicate them.

[Stig / Major Tom]

Small crack in intake boot?
Boot loose?
Soviets again.......?

I got nothin here...
Stig

[ScooterLar]

Another great source of information is the Honda Elite 250 Yahoo group. The Helix has the same motor as the Elite 250, so mechanically, they are identical to diagnose. I used to be a follower/contributor there for several years before I sold my Elite 250 a couple of years ago. Great group of folks over there.

As already mentioned, besides a good cleaning of the carb, I would take a close look at the intake boot. Those are notorious for dry rotting and getting brittle as they get older and exposed to high temps. Since your bike is almost 25 years old, a vacuum leak at the intake boot is a distinct possibility.

Might want to try the folk on: The Honda Helix Discussion Board
http://www.slonaker.net/helixforum/viewforum.php?f=4

[Redk]

Not this guy, Red!

Karl

:-)
redk


Mr Paul...  It should not be necessary to replace the float...  test it when removed by holding with a pair of pliers and dunking in a small container of really hot water.  If there is a leak in it, there will be bubbles coming from that spot, which most likely may be repaired.

Yet if it does have a leak in it, if inspected shortly after removal from service, you would be able to notice liquid within it's hollow body, by shaking ??

Gosh it will be fun to see this one resolved !
:-)
redk

[Mr. Paul]

Small crack in intake boot?
Boot loose?
Soviets again.......?

I got nothin here...
Stig

I replaced the boot when I got the scooter last August. When I pull the carb, I am going to put a new one one just because. I suspect Putin may be behind this.
My scooter has been hacked!