Very week spark?

[jasonwcali]

Hi everyone. Ok first of all please dont lagh but I love my little trike. I have a 77 Honda ATC90 This little thing has reliably "Up untill recently" taken me far and away to the midle of the forest and back. Last year I was having big blug issues. I was replacing 4 plugs for every tank of gas. Do to removing plugs so often I striped out 3 heads. each time I would buy another head from Ebay and do this all over agan. Since the last time the little trike has no run. The spark is there "Somtimes" but it is very week. Plug, Condenser and Points have 0 miles on them. Coil is the one that came on the 90 when it was given to me. I have changed the rotted exaust to a cobra HP exaust, Brand new plastic tank, rebuilt carb as well as a new plug wire, For all intents and purposes the think should run but it dose not. When I got it it had little to no wire harness so I got some wire of the corect size from work and redid it acording to the repair manual diagram. I am told this can be a problem because its not automotive wire, is that right? Keep in mind this little thing has hudreds of miles on it with this same wire before this problem started. Any ideas? Thanks in advance. By the way I am in Ione, California near Sacramento, just joind and looking forward to meeting others as well as learning thanks

[MTS]

Pop your pullstarter off, the Stator/rotor are known for Shorting out after awhile, and the rotor can even chunk and come apart(mine did it) as for 3 heads, Did you make sure the valvetrain was ok and that the valves where set properly? sounds like the 90 needs a rebuild if its huffin blue that bad, i would just put a set of rings in it and check the valve Seals (very unlikely to go) check the valves make sure there not bent ect, the 90 will Run forever on worn out ring's n whatnot, i know mine had like a 70 Thousands gap in the rings when i took it apart (no *Edited**Edited**Edited**Edited*) ....Have fun!

[Unclediezel]

Go over the points about ten more times------They are "SUPER -PICKY" and leave No room for error----Especially if your describing a weak spark situation--- Hondas have had problems with them since the dawn of Time-----

to the boards

[jasonwcali]

The motor uses no oil at all. No burning no leaking. For all intents the motor is in tip top shape. I never found out why but for some resone after riding a few minutes the plugs would just crap out. After removal they had no oil or gas on them and lookd darn near new just would not spark anymore. Put in a new plug and everything was find for a few more minutes of riding. I did this so much I would wear out the threads in the head as well as burn a hole in my walet buying 40 plugs for a weekend LOL Is there any way to get past hondas week spark problem? I have had the pull starter off and the coils in there out. I went over it all with a wire briush on my rotory tool as they had rust on them. Everyhhitng behind the pull start for the most part looks good. hmmmmmmmmmm I have a ghost in my motor. Is there a particular reason a new set of points would have a decent arch when you turn over the motor? my repair guide says if the points arch they need replacing but they are brand new.

[Unclediezel]

You answered your own Q---
#1 if the points arent gapped propperly-saturation time on the coil is reduced , hence low firing voltage to the plug---as the plug heats up resistance increases- (Especially with resistor type plugs)
#2- Im not sure if you have one or not on your model, but the "Resistor -Boot" for the plug may be failing---new ones are cheap enough(Or at least much cheaper than 40 spark plugs) --so if in doubt- change it--
#3- Consult a few different sources and make "ABSOTIVELY-POSILUTELY"sure you are using the correct heat range plug...
#4 if you ARE using a resistor cap--make sure you arent using a resistor plug---!!!!

[jasonwcali]

Oh man I am confused now. Ok lets see. Even with the point gap set coeectly I have a week spark and the points arch. I have gone over these points countless number of times. It has been mentioned to me about using a "Hoter plug" However I am using the same plug recomended in the manual. I am sorry but I have no clue what a resister plug and boot are? When I replaced my spark plug wire I replaced the boot and everything "No problems" I am not using an NGK plus like the manual said but the crossrefrence for Champoin is the same as a 97 Ford Ranger. Hmmmm so I guess my question would be what is a resister plug? what is a resister cap? Thanks for the welcome by the way. I hope to learn a LOT and meet a lot of people.

[Vealmonkey]

The new coil from honda costs $114 and comes with a new condenser, I can't remember the cost of the Honda points. I don't know if you can get a new wiring harness from honda but I picked up an nos wiring harness from ebay for $25. When you changed your exhaust, did you rejet. I'm sure you would have to go up a size or 2 on your main jet. As for changing the plugs so much you wore out the threads in your head, try a little anti seize on your spark plug, but it sounds like your were overtightening your spark plugs. You could have a short in your wiring somewhere. If a coil overheats, it will build up resistance and quit working, shut off. What kind of shape is the carb in. If you are having fuel problems, you could just be running out of gas in your fuel bowl and by the time you are changing plugs the fuel bowl could be filled back up. Are you running clear fuel strainers on the fuel lines, if not try 2 of them and you can see if you have a good supply of fuel to the carb. An electric problem can be hard to figure out but you should try and find all new stuff to get it back right. I know it can be an expensive pain, but I can't imagine how much you have spent in spark plugs.

[jasonwcali]

I know its not a fuel problem, I had a fuel problem "Cloged screen" and fixed it. As I said everytyhing other than "no spark" seems in tip top shape. WOW thats prett expencive for a 1977 coil LOL I think I see them on ebay for 10-20$ As far as the wire harnes gose I built it myself using wire I got from work. Its not automotive wire but for the first several hundred miles its worked great. I think the reason I kept ruening my heads was because I was changing sparkplugs over and over on hot heads. The one would go out so I would pop it out and put a new one in and hit the trail. I should also note that this frame up build of this thing was the first time I have ever built anything automotive. I changed a transimition in an 81 toyota but other than that I had no automotive expertise. I think It might be a good idea to go ahead and tear everything back down and go at it agan now that I am a little biut more knowledgable about this stuff. I did run my hot coil wire under the seat and started having problems a couple years ago. I found that the lip on the stamped mettle frame cut into the wire and shorted the coild to the frame. I will look around and see if I cant find anymore wire problems. Unfortunatly I gave this thing to my brother earlyer this year and he gave it back a couple weeks ago so all the spare parts and manual are still at his house. Hopfully this week I will be able to pick them up. As far as rejeting I considered that but the little thing ran so good after I instaled the new exaust I figured why mess with somthing that works this good. As far as price I know what you mean. $150 for exaust, $50 spark arestor, $120 new plastic gas tank, points, condenser, 40 plugs a weekend LOL Who cares that it gets good gas milage when it mechanicaly nicle and dimes you to death LOL As I said before thanks for the help thus far but the 77 90 saga continues, I will go check some of thos ethings right now.

[dufrain]

The reason you are stripping the head is the aluminim expands more than the steel in the plug so when it heats up the hole is extra tight.Use anti sieze on the plug threads like vealmonkey said.If the wire you used for your wiring harness patches is the same size as the stock stuff and the insulation is ok it will work fine.I would go check your splices.I would change that main jet to since when you changed the pipe you changed the amount of fuel it needs to run right.Id go up a size or two also.

[jasonwcali]

Well, no shorts in the wire harness. I will be replacing all plugs as a precautionary mesure just in case but other than that I am still stumped.