i beg for your help -yz 80 no spark

war child

Member
Jan 4, 2009
75
0
help -yz 80 no spark

1996 yz 80

hello all fellow petrol heads , i realy do beg for your help my little brother saved up for 6 years to buy a little bike- yz 80 and has had nothing but problems he never gets to ride it, im trying to look after him and the house and we , me dont have much money as my mum just packed up and left him so i cant keep paying to have this bike fixed , so i have had to resort to fixing it my self, and im just a plumber, not anything to do with engines, so any help would realy realy be aprecated,

things we have had done so far new head or sumething , which involved new piston and rings , cleaned out his carb realy well and after tis it worked for 20 mins and then died again he is realy upset now and im trying to fix it,

the problem is there is no spark, so i got his manual and got a multi meter and set to work, my multi meter doesnt have all the ohm settings that the manual asks for like if it saya 100k i have 200k, if it wants to be tested at 5k or oms i have 20 k, ohms ,

but what it does do is give me reading and the only place i dont get anything is when i check the secondry coil resistance in the magneto, i think its called a magneto, it the bit near the fly wheel were the wires come out of the engine any help very much aprecated, thank you
 
Last edited:

war child

Member
Jan 4, 2009
75
0
so upto now then all test on electics have gave me a reading weather right or wrong but on my secondry coil resistance test i get nothing , is this enougth to cause no spark even thougth there is a reading on the primary wires coming out the magnets, which i think is the right reading from what i checked
 

sharky243

Member
Dec 14, 2008
246
0
The ignition systems on these bikes are not all that difficult. It is a process of elimination really, when diagnosing them. Start with the basics first. Try a new spark plug. Then disconnect the kill switch wires. Inspect the entire wiring harness for any bare, broken, or shorted wires. Check all the ground connections. Then check the trigger coil on the stator plate for proper resistance (ohms). Check the generator coil(s) for proper resistance. Check the magnets under the flywheel for good strength. Then check the main ignition coils primary and secondary windings for proper resistance. Check the high tenssion lead (spark plug wire) for breaks. Check the spark plug cap, some of the caps have resistors in them and they can fail. All of the specs are in the service manual. You may need to barrow a different multi-meter to perform these tests if yours does not have the required settings. If any of these parts fail to meet specs, or show an open circuit, They are most likely to be the cause of the problem. If everything tests out good, try another CDI module.
 

war child

Member
Jan 4, 2009
75
0
right i have had readings on a difrent multimeter and the problem is there is no reding at all coming from the secondry coil in the engine what does this do and would this stop the spark
 

war child

Member
Jan 4, 2009
75
0
hi i have checked all the things listed in the manual, but there isnt much , and i did them all there is only the secondry coil not giving a correct reading , i also checked the ground and looks ok is there a way i can test the ground would this stop the secondry coil, which is wrong
 

sharky243

Member
Dec 14, 2008
246
0
It sounds to me like you have an "open" circuit in what you are refering to the secondary coil. The winding is supose to be grounged to the coil lamination(the metal plates). If the ground wire has broken away, this will cause an open circuit which will cause a "no spark" situation. On some of the older bikes, the ground wire for the coil was soldiered to an eyelet which is secured under one of the coil mounting screws. It may be posible to re-soldier the wire back onto the eyelet. If the ground wire is burried under the winding of wire, you will have to either have it re-wound, or replace it.
 

war child

Member
Jan 4, 2009
75
0
thanks for the help, sharky, it is becoming a little clearer , what exactly is a open circuit, ive tried google but dont get any help because of so many difrant meanings
 

Slipzz

Member
Jul 2, 2008
15
0
I had a 1996 yz 80...Thing was terrible! Went fast and all, but had SOOO many problems with it. Sold it wrecked for $550.
 

sharky243

Member
Dec 14, 2008
246
0
Think of a light switch. You turn it on to turn the light on. This is concidered a "closed circuit". When you turn the light off, you "open the circuit". Electricity can't flow through an open circuit, so the light goes out. Electricity needs a continuous path to get from point A to point B. If there is a break in that path, electricity can't flow. Here's a simpler way to think of it. You're driving in a car, and you come to a river, and you need to get across that river. So they build a bridge to continue the road over to the other side of the river. If the bridge was out, you couldn't cross that river. Thats what an open circuit is in an electric circuit. I hope this helps you understand it better.
 

war child

Member
Jan 4, 2009
75
0
thanks sharky , i get you now , so when the electric goes out the wires on the primary feed to the cdi and the box with the big cable that conects to my spark plug, which might i ad on the primary feed i get a low reading and when i kick it i get 144 which is a high and corect reading , why does there need to be power from the secondry feed coil , does the primary feed run out to the outher stuff and return to the secondry thus completing the circuit, does the primary feed open a gate to let the secondry feed do the proper current to the cdi and spark pug box thing, why when i kick the primary and the is a charge go up the primary do i need a second coil in the fly wheel engine magnito thing , what the hell does the second feed do , because it doesnt show any power ever
 

sharky243

Member
Dec 14, 2008
246
0
The coil(s) under the flywheel are generator coils. They generate electricity to power up the CDI module, and also supply power the the main ignition coil to create a spark. If the generator coils are not working, it's like a power failure in your house. No power, no lights. The CDI module uses a trigger coil, also down at the flywheel, to know when to make the spark. When the timing is right, the CDI sends electricity to the primary windings in the main ignition coil. The electricity transfers to the secondary windings of the main coil and gets stepped up to a much higher voltage and fires the spark plug.
 

sharky243

Member
Dec 14, 2008
246
0
it's ok War Child, you don't owe me a thing. I don't mind helping people out. Besides it sounds like you have enough on your plate, you don't need to worry about me. You can
get my e-mail address from my profile and contact me any time you need help with anything at all.
 

Ol'89r

LIFETIME SPONSOR
Jan 27, 2000
6,961
45
war child said:
1996 yz 80
so i have had to resort to fixing it my self, and im just a plumber, not anything to do with engines,

war child.

Something that may help you understand electrical is to think in terms of plumbing. Think of the electricity running through the wires as water running through pipes or hoses. Closely check all of the connections for proper contact and possible broken wires next to the connectors. Check for oxidation in the connectors and use dielectric grease when plugging them back together. Also make sure all of the grounds (Earth to you guys in the UK) are clean and well grounded. Sometimes it's the simple stuff.

Sounds like sharky has covered about everything else.
 

macgillivaryd

Member
Jun 12, 2009
1
0
YZ80 coil resistance specs....

Could someone who has a manual let me know what the resistance specs are for the source, pickup and ignition coil specs are for a 1991 YZ80... I don't have a manual and am trying to fix my nephews bike...tks
 

2strokejonny

Member
Oct 8, 2018
1
0
YZ80 coil resistance specs....

Could someone who has a manual let me know what the resistance specs are for the source, pickup and ignition coil specs are for a 1991 YZ80... I don't have a manual and am trying to fix my nephews bike...tks

Primary source coil-Brwn wire to blk wire 500
Pulse coil white/red to white/green 10.2
Specs should be +/-10% my source coil tested 420 but works fine.
 
Top Bottom