Planet Minis

bidabing007

First off, sorta of a newbie to certain aspects of motor work, i know enough to create more problems than fix them, once in awhile i get lucky and fix something.
Anyhow, after a week of detailing my 1970 CT70 that's been waiting for me for 7 years now, I go to start her, kick starter breaks off, (previous owner tac welded, lasted 5 kicks) ok i think, i have a couple of spare motors, I just wanna ride her, I will do top end (low compression anyhow) & kick starter shaft later.
Put standby motor in, has great compression, no spark, hmmm, previous motor sparked, real nice, I swap the points, coils & condensor along with the rotor, trying to keep known working parts with same. Still no spark??????? Am i barking up the wrong tree? I have taken ALL the above off and on 3 times now, moved the points from left to right & centered, tightening down, cranking rotor counter clockwise, still points not moving that i can see, PLEASE rscue me!

doopsx3

same plug

bidabing007

same plug, and tried couple of others

bidabing007

just put brand new one in, no help

LoudFastUgly

38 year old wiring harnesses don't necessarily like to be disturbed.

Check and make sure your coil is well grounded. Check for spark.

Looking IN TO the plug coming out of your magneto, if the connector clip is at the top, I believe the bottom left wire should be black or black/white. It is one of the bottom wires for certain. Jumper it to the small wire on the coil. kick and check for spark.

doopsx3

that is possible for sure

bidabing007

jusr dopped motor for 2nd time today, pretty frustrated, #@#$!$R%$%!$#@%$#@%$%$%$#%$#, ok, so, i dropped it to put another coil in, (hands TOO big to go gas tank route). The previous one was a little "quarky". spark plug cap not seated real good, thought i would try another coil ( ANY WAY TO TEST COIL?) anyhow, no help, will go back at it in the morning, she's all pretty, new paint, buffed EVERY single bolt i could get my hands on, shines/sparkles like a diamond, really just wanna ride her, i'll have to wait another day and try your suggestions, thanks for your help, really appreciated!

dirtbkr188

Make sure you clean the paint off all the wire ground areas, and make sure all the electrical connections are firmly plugged together. Sounds like you aren't getting a good ground to the frame.

mexicanyella

Test coil: Get a 6V lantern battery or an automotive battery charger with 6V output. Find primary wire that feeds coil, and unplug it.

With
a) coil installed on bike,

b) negative terminal of battery or charger grounded to motor or frame where it can get a good ground, and
c) spark plug in plug wire laying on head or jug as if doing a spark check,

you should
d) lightly brush the 6V positive current source against the coil's primary wire , so it makes momentary contact and then breaks contact. This simulates the action of the points, charging the coil's primary winding then interrupting it. If the coil's working you should see sparks at the plug simultaneous with this make-and-break action.

It's easy, if you can get to the coil's primary wire (which on a CT is maybe not so easy) and telling.

Your coil is probably, but not definitely, okay and the problem is probably points that need to be filed flat and regapped. Remove the flywheel to file them if possible. I just filed mine through the hole in the flywheel after losing spark--surprise!--and it did the job, but you can do a more thorough job without the flywheel on there. Use a points file or emery board from your old lady's hand-beauty supply storage area. Points files are better and get less gritty crap all over in there. File off all peaks and pits, as best you can, trying to keep the faces meeting one another squarely when the points are allowed to close. Clean the faces and all surrounding area with electrical contact cleaner, NOT carb or brake cleaner. The electrical stuff won't leave residue or dissolve the resin off the nearby windings. Get it all clean, reinstall flywheel and gap points to .012"-.016". Chances are you will now have spark.

If not, it's probably a wiring fault between the magneto and coil. I've not owned a CT yet, but I've never had a problem more serious than points needing the above steps with a 6V Z50 ignition, which is the same unit as a 3-speed CT70. The only coil failure I've ever had was just due to a dry-rotted coil wire leaking spark to ground...forgot to mention to check that, sorry.

Try those things and report back with results; good luck.

FastMC

You said in your first post you swapped the points. Make sure the points wire connector is insulated from the points base. There are a few little insulators plus a small insulating sleeve on the points screw to keep everything insulated from ground. If the wire is making any contact with the points base-no spark. Just one more thing to check.

bidabing007

Ok, going to try suggestions. Couple of things though:

1: I cannot see points open and close through the holes on the rotar, seems that I have seen other CT & Z motor points open and close through the oval holes when spinning the rotar, counter clockwise?

2: When I took rotar off motor that had plenty of spark, little brown pieces of plastic were inside . I see the "spacers" on the magneto coils have these on top and bottom. 1 spacer is defintely gone on 1 of the coils, will this cause shorting? Fix with? Thinking of wrapping electrical tape in the gap it left from crumbling apart? Kinda of bunching up the tape or cutting the electrical to size and wrapping it in the gap? this necessary? it was working before, hmmmmmmmm

Really appreciate you guys, will post pics after bike is running and buttoned back up nicely.

PS: The ole lady took the kids and the nail file! Now what! LMAO

mexicanyella

I've not had occasion to remove stator coils from a stator plate yet, so I don't know the spacer configuration, if any. I do know that the points have a browninsh resiny plastic "heel" that rubs on a cam on the backside of the flywheel. I wonder if that came apart, except you said that was on the motor that had spark.

The points should definitely be opening visibly as you rotate the flywheel. They should start to open as the F mark stamped on the flywheel rim passes the notch in the case edge. Sometimes the T and F marks get obscured.

But in any case, you'll see that there's a notch in the points base and one in the stator backplate just opposite it. You want to loosen the points mount screw just enough that by sticking a screwdriver into this notch (one screwdriver edge in the points notch, the other edge in the stator plate notch) and twisting the screwdriver, it moves the point base relative to the stator plate, changing the gap.

Sounds like your points just aren't adjusted enough for the flywheel cam to open them, and when you move the base this way closer to the flywheel the points rubbing block "heel" thing will begin to contact the flywheel and you'll see them open against spring pressure.

Get a points file at a decent auto parts store; I got mine at NAPA and it was less than $10. Lasts longer than emery boards and requires less cleanup.

bidabing007

going to work on her, keep you posted

bidabing007

psssttt, WE GOT SPARK!!!!!!!
k, found it easier to take rotor off and adjust points, after tinkering, they are opening and closing from "F" to "T".
Problem:
Bikes starts, then putts out, whew, nothing the like sound of a minitrail motor, has distinction like no other bike, similar to Harley having their own sound.
1: I am thinking a little more adjusting on points? Try to get my fueler gauge in, going to look for smaller one, adjusted to .014, think the range is .012-.016 went in middle.

2: I had thorttle needle clip on 2nd from top setting, put it to very top, plug seems too wet on either setting. (friend taught me years ago reading plug can tell you tons of info)

3: Firing too early cause of points not right? Thus wet plug and cutting out? I realize float might need adjusting, I think I should square away points first, then move to carb?

bidabing007

Also, how do you tell oil pump is working? I can't remeber history on this motor, I can see new gaskets on top end, thinking I need to verify pump is ok for safety, don't want to have to rebuild top end.

bidabing007

ALso, settings on Air to fuel & Idle adjustment screw? 1 1/2 turns?

LoudFastUgly

You'll know if the engine has oil pressure easily enough, run the engine briefly and then remove the top rocker cover. Check for oil.

Set idle screw; adjust in until the screw starts to lift the valve, set air screw, adjust idle to preference.

Set air screw; 1 1/2 turns out from softly seated. Warm engine, adjust for highest idle. Done.

bidabing007

decided to hold on and run down to Honda, need air cleaner filter, have to wait til Tues to pick up, going to button her back up some and look around for substitue air cleaner before i proceed, hmmmmmmmmmm, what can i use? womans toiletry pad? none around, thinking............ ideas?

mexicanyella

Just keep out of environments where there's a bunch of airborne dust, rocks, and squirrels. If you're just talking about a couple quick test rides, you won't kill it with no filter if you are careful. Might run a little lean, but might not. My Z runs the same with or without the filter.

bidabing007

ok, wrap up another day, spark-GOOD, run-NOT, starts then stops when i start to give her gas:

figured out air cleaner temp, using thin foam, couple of layers to look like OEM filter
double, triple check points - looks good
adjust throttle needle, all settings, same thing- no help
check bowl- half full (or half empty for others)
plug still seems wet
clean out jets in carb for 3-4 time, all look good (anyone know the let sizes?, should probably make sure they are correct
pull off timing chain cover, rotate counter clockwise to get top dead center (until freeplay at "T") on rotar, cam chain gear "0" in line with notch on head

SUGGESTIONS? listening