ct70h stator=spark problems

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mechanicmike15

Member
Hey I have a 71/72 ct70hk01 that i bought from my neighbor (im 15) but i have had a issue with getting it running i have fixed dirtbikes and a bunch of other stuff but the ct70h is being a bit stubborn. Engine timing is perfect and all, havent messed with it but I have found out the problem which apparently was the stator. i have replaced th ignition coil, stator assembly system, battery sparkplug and fuse. I am not gonna lie I love this bike to death but its just getting a little annoying ( pretty awesome bike seat is still perfect and everything =). The bottom line is that it is not getting anny spark to the sparkplug but when i kickstarted the bike i held the wire from the ignition coil that goes to the sparkplug and got electricuted. Since it still was not giving any spark to the sparkplug i took it all appart and am rebuilding it again to see if it might work. I know that there are gappings for the points which i think is .625 but dont know if there is supposed to be a gap for coils. trust me im VERY VERY mechanically inclined but this is a head scratcher + the BIKE HAS BEEN SITTING FOR 43 YEARS . P.S it has a mitsubishi flywheel IF ANYONE KNOWS AND CAN HELP THAT WOULD BE GREAT thanks.
 
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Epic_username

Epic_username

Member
So new coil, did it have the plastic plug for the sparkplug already on it, or did you re use the old one? The connection between the cap and the coil wire may be crappy, and no spark
Did you drop the spark plug? or do something else that may have damaged the inner electrode? You sure its spark? Spray starting fluid or brakekleen in the sparkplug hole, see if it fires.
Or, take another sparkplug off a running engine, doesnt have to be the same, plug it in and see that one sparks.

Otherwise, check for bad grounds, loose connections. The battery and fuse have nothing to do with it running. The black loop on the battery plug is the coil secondary (or primary, I cant remember which is which right now). the loop is there so people dont ride without a battery and blow out the bulbs.

Other than that, idk. Just make sure you arent getting the lighting coil and the primary coil under the flywheel mixed up, etc.

could just be old too. Im 15, when I got my first K1 it would spark, run, but it wouldnt idle. If its hasnt run in years it needs to clean itself out.
 
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mechanicmike15

Member
no used new one of couse the old one would be coroded because i live in florida. and no the spark plug is brand spankin new

---------- Post added at 08:06 PM ---------- Previous post was at 07:59 PM ----------

no i used the new one the the old one would be corroded. ps love impalas. I had a 72 4dr mercedes and pulled the straight six and put a smallblock chevy pretty cool. oh and how is the suzuki doing?=) oh for the idle on the bike you could adjust the carburation of gas engine takes
 
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mechanicmike15

Member
na i literally cleaned and polished every nook and cranny so its rust free and not a problem its giving electricity but i was thinkin that i should put an impact drill to the engine like a makita high torq gun to produce enough electricity to give spark. srry if i dont know if posts are knew or old its just that im new to this posting thing because im usually in my garage alone fixin cars , motorcycles and welding frames so im new to this forum site. last car i had was a 65 4 dr impala and before that was the mercedes.
 
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mechanicmike15

Member
well i bought a kit that came with a new condensor so thats not it. i think that the bike is not getting enough electricity to the ignition coil but ill check it out.
 
Epic_username

Epic_username

Member
well man i really hope you figure it out, it really sucks to have a bike your dieing to ride but just cant. youve eliminated anything that would give bad spark
i bet racerx would know
 
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bry593

Member
no such thing as '55 impala. 1st impala was '58. chevy only produced two car bodies in '55, vette and 150/210/bel-air...

your stator has two coils. the front one is the magneto, used to charge the high tension or "high voltage" coil located under the gas tank area. the back one (nearest the sprocket) is actually 2 coils wound on the same axis (see the yellow and green wires?). the yellow coil powers only the headlight, so that is why the headlight gets brighter with increased rpm. the green coil powers the battery and all other componenets (horn, tail, blinkers)...

the magneto coil is the only one you need to make your bike run. see that black wire? it goes to the spark plug coil and charges it up to a very high voltage. the points are a switch (like a light switch) that ground this black wire out, and when that happens, it makes the plug coil dump all that voltage at once. ZAPPO!!! this has to happen when the cylinder piston has compressed the fuel and air, that is what timing is all about...

the good news is that your spark plug wire shocked you.... no seriously... that means you are getting juice to your plug coil and that your wiring is probably okie-dokie...

my guess is that you need to properly gap (use a feeler gauge) and properly time the spark (move the points assembly by loosening mounting screws and sliding the assembly in the slots).

see if you can find a service manual or instructions on the net, "CT70 service manual". read the instructions on how to gap the points, and then if you have any questions, just ask.

i was a pretty good 15 yo mechanic myself at one time....
 
Epic_username

Epic_username

Member
I dont know if the 4 speed point gap would be different, ive never worked on an H model myself, but my 3 speed runs pretty good with a .036mm point gap
 
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bry593

Member
the 3 spd and 4 spd gap are the same... the difference lies in the harness and sprocket gearing.. hko lights the headlight, high beam and speedo... ko just lights the headlight and high beam indicator, so they have differnt bulbs... i know, stupid... but the hko turns 4000 rpm on average while the 3-spd turns 4500+.... yeah, i know, still kinda silly.

starting in late '78, honda went to an alternator, and some of the idea changed. ironically, the headlight is still driven off the yellow wire instead of the battery. that means, it goes dim at idle... DOH!!!
 
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mechanicmike15

Member
55 impala

bry593 said:
no such thing as '55 impala. 1st impala was '58. chevy only produced two car bodies in '55, vette and 150/210/bel-air...

your stator has two coils. the front one is the magneto, used to charge the high tension or "high voltage" coil located under the gas tank area. the back one (nearest the sprocket) is actually 2 coils wound on the same axis (see the yellow and green wires?). the yellow coil powers only the headlight, so that is why the headlight gets brighter with increased rpm. the green coil powers the battery and all other componenets (horn, tail, blinkers)...

the magneto coil is the only one you need to make your bike run. see that black wire? it goes to the spark plug coil and charges it up to a very high voltage. the points are a switch (like a light switch) that ground this black wire out, and when that happens, it makes the plug coil dump all that voltage at once. ZAPPO!!! this has to happen when the cylinder piston has compressed the fuel and air, that is what timing is all about...

the good news is that your spark plug wire shocked you.... no seriously... that means you are getting juice to your plug coil and that your wiring is probably okie-dokie...

my guess is that you need to properly gap (use a feeler gauge) and properly time the spark (move the points assembly by loosening mounting screws and sliding the assembly in the slots).

see if you can find a service manual or instructions on the net, "CT70 service manual". read the instructions on how to gap the points, and then if you have any questions, just ask.

i was a pretty good 15 yo mechanic myself at one time....
Click to expand...
my bad i meant 65 impala now i feel stupid lol. but ya i loved that car to death. srry about the mixup by the way i love chevrolet:monkey:

---------- Post added at 01:24 PM ---------- Previous post was at 01:07 PM ----------

---------- Post added at 01:26 PM ---------- Previous post was at 01:24 PM ----------

got it off of e bay it cost about 42 dollars here i will give you the link but WARNING if you buy it you are goin to buy it you r gonna have to drill bigger holes in the stator to adjust the gap between coil and flywheel because it may not fit the mitsubishi flywheel and stator plate but if you buty the mitachi flywheel and statorplate then it will work heres the link HONDA CT70H STATOR KIT HONDA TRAIL 70 H-MODEL CT70 | eBay

---------- Post added at 01:34 PM ---------- Previous post was at 01:26 PM ----------

by the way bry593 do you know the gapping for between the coil and flywheel i believe it is .017 but just want to make sure.

---------- Post added at 01:40 PM ---------- Previous post was at 01:34 PM ----------

my bad i meant 65 impala now i feel stupid lol. but ya i loved that car to death. srry about the mixup by the way i love chevrolet

---------- Post added at 01:49 PM ---------- Previous post was at 01:40 PM ----------

indeed i was actually glad when it chocked me
bry593 said:
no such thing as '55 impala. 1st impala was '58. chevy only produced two car bodies in '55, vette and 150/210/bel-air...

your stator has two coils. the front one is the magneto, used to charge the high tension or "high voltage" coil located under the gas tank area. the back one (nearest the sprocket) is actually 2 coils wound on the same axis (see the yellow and green wires?). the yellow coil powers only the headlight, so that is why the headlight gets brighter with increased rpm. the green coil powers the battery and all other componenets (horn, tail, blinkers)...

the magneto coil is the only one you need to make your bike run. see that black wire? it goes to the spark plug coil and charges it up to a very high voltage. the points are a switch (like a light switch) that ground this black wire out, and when that happens, it makes the plug coil dump all that voltage at once. ZAPPO!!! this has to happen when the cylinder piston has compressed the fuel and air, that is what timing is all about...

the good news is that your spark plug wire shocked you.... no seriously... that means you are getting juice to your plug coil and that your wiring is probably okie-dokie...

my guess is that you need to properly gap (use a feeler gauge) and properly time the spark (move the points assembly by loosening mounting screws and sliding the assembly in the slots).

see if you can find a service manual or instructions on the net, "CT70 service manual". read the instructions on how to gap the points, and then if you have any questions, just ask.

i was a pretty good 15 yo mechanic myself at one time....
Click to expand...
 
OLD CT

OLD CT

Well-Known Member
thats what i thought.the correct stator coils and plate are sold brand new for 89 dollars from dratv and a few bucks more for the connector.you bought yourself a headache unfourtunatly.how are you going to know the proper gap?rigging what you have purchased is not going to be as simple as one would think.
 
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mechanicmike15

Member
ya but once its finished and I ride the bike it will all be worth it but honestly i checked it out and basically thats my last alternative if this doesnt work out + i did not know about dratv until 5 months after i bought the stator kit because i mostly fix cars and 125cc-1200cc motorcycles i was always interested in the ct70s but never new i would have a rare 4 speed in my neighbors shed. PS whats the point of being a gearhead and mechanic if your not gonna learn something new from the expirience. trust me when my first mini harley stopped running when i was in 2nd grade , by my self i pulled the engine out and took it appart after that i found that the flywheel was worn out and damaged and luckily my dad was able to get me one and was able to put it back on and it worked. even before that when i was in kindergarten i always used to pretend i was a mechanic fixing my little electric car (hey i was really little). Ever since i have been doing this and i guess this is what i was made for, its what i love.
 
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bry593

Member
The following is how Honda recommends adjusting the points (see ST50 owners manual at the website I pm'd you).

Rotate the flywheel until the "F" mark aligns with the timing mark on the crankcase. Points should just begin to open (that is the timing part). If adjust is required, loosen screws and slide point assembly until correct. Next, rotate the flywheel counterclockwise until points are at maximum gap. The point gap should be = .012-.016".

As for coil end to flywheel magnet clearance, there is no Honda spec as it is supposed to be non-adjustable. If you had to slot something to make the chinese parts fit, then I would set it at about .010". That's the gap I use on briggs mower engines, should work for the Honda. Might be hard to do since the flywheel covers the coil. I guess it's too late to go back to your original magneto coil?
 
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mechanicmike15

Member
well not exactly i still can maybe reuse them + rewire them but i need to know the gap because i had drilled biggr holes to adjust the ones from the kit but im starting to thing of buying them from dratv if this doesnt work but i just hope the one from dratv works though
 
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