No spark gt125r 06
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Bike Model = : Gt125r 06 carb
No spark 2006 gt125r carby (bought the bike as a non runner cranks but no Spark, all electrics work)
Hi so before posting I’ve tested the battery, HT leads (coils), replaced the spark plugs and tested the cdi unit (resistance)I got a reading for the pickup coil and it is:
105.1ohms
And the reading for the stator is: 07.8ohms
I’m not sure if these are good readings or bad.I then decided to test the blue wire that goes from the pickup coil to the cdi unit end of the wire and got no continuity? (No beep or reading).
And with the green wire i got 117 on continuity mode.So I’m unsure if the wire is the fault or if the pickup coil or magneto is faulty
Bike been in shed for 3 months i need help plz 😭
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Sounds like a faulty stator unit, because if the CDI can’t sense it, it won’t send any sparks to the coils itself.
Did you also measure primary & secondary resistance of the ignition coils fella ?
Also if you can, remove the “HT CAP” thats on the coil itself. Then put your meter to 20,000 ohms.
Measure the HT cap on its own, tell us the resistance. The black caps are common to fail the sparks due to heat damage after a long while in the bike, since down the plug hole gets very hot. Though I would normally suggest to just upgrade to the heat resistant rubber NGK caps (NOT PLASTIC ones , they will crack!) , but if the black caps are OK , then go on amazon and look for “MAGNECOR HT WIRE” , these HT wires are great for maintain a consistant connection between the CAP and the Ignition Coil itself.
// Meditation doesn't mean you have to sit still....
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I must stress, before fitting a new stator , get a BEEFY regulator. Like the one you see on the store above ^
NO aliexpress , No Korea OEM regulators = these things are usually so bad its the #2 cause of all electric problems on the bike and plus some of them allow the battery to charge to 16v and fry the loom. Not worth the risk.
Just a shout!
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Hi, i did check both primary and secondary resistance of the coils.
The cap readings are (multimeter set to 20k)
Coil 1: 8.73ohm
Coil 2: 10.40ohmRegarding that blue wire that goes from cdi unit to pickup coil. I’m not sure if it is faulty as i was not getting continuity when i hooked the multimeter to the pickup coil end of wire and to the cdi end of wire.
Oh and will purchase that regulator once I order the other parts, so do i go ahead and order the stator and pickup or should I do more testing?.
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Stator + Regulator together = on your basket , definitely will NOT trust using any old regulator on a new part as these 2 parts are married like chain & sprockets.
Caps = They seem OK? If they don’t spark, get NGK ones but if budget is a concern, then we have these ones that work.
We have 2 of them left:
https://www.ebay.co.uk/itm/256805062129Make sure you have dust caps!!!!
https://www.ebay.co.uk/itm/254136676637Spark Plugs = Go to halfords and get “Yellow CR8E” only , do not touch the “IX Blue Iridiums, they are “!#@” is all we can say.
When she runs , upgrade to the “LASER” ones you see on this bike forum.CDI unit = It should be OK, but it’s the last thing we need to replace right now. Just make sure the main bike harness has every connector / plug cleaned up with shiny pins. Use contact cleaner and dry over night. Then ONLY use “ACF50” (spray a tear drop / rain drop of that in every single plug on the bike) .
Good job on checking the actual ignition coils. What are their readings without the HT cap attached to them?
Regards
// Meditation doesn't mean you have to sit still....
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Hello again
Soo Ive got some NGK CR8E sparks i bought from Halfords earlierThe readings for the coils without the caps are:
Coil 1: 5.70ohm
Coil 2: 5.72ohmGonna order stator unit and regulator now, stator unit should take about 15 days or more to arrive, are there any more tests i should conduct whilst i wait for the parts?
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1 more test , “Coil TERMINAL pin + Coil Bolt Hole” ==> What is the resistance (less than 5 (five) ohms please) Then i will tell you if the coil is good.
If you order the stators from us, it may come sooner than 15 days but possibly! – I usually try to be as rapid as I can.
In that time, strip her and clean up the harness and get “harness tape” , wrap it twice to insulate it more , but i hope this keeps as much water and mud away from rotting the wires.
Believe me , I washed my bike yesterday and I was stupid to allow water inside the seat , the fuse box got a little wet, i dried it off and i lost 1 volt! = 1 volt!!!
So instead of 12v, i was at 11v, the starter motor would not crank. So i replaced the fuse again and re-cleaned the terminals , it started up good! – It is amazing that water or bad contacts can cause an easy voltage drop (higher resistance , so heat risk there too!) Any harness made after 2012 is SENSETIVE!
I had an 2008 GT carby for a while, it’s harness was 2x thick and said “GT250R” as the factory harness used on both carby 125 & 250 until 2008
If your 125R is 2016 , you would be extra careful with the harness as they are much thinner.
Since you have a 2006 bike, i hope your harness says “GT250R” in a white sticker near the battery area and you have a thicker one (i’d be jealous as they are very hard to get now and last for ages!) All 650GT after 2008 are EFi now, so oh well , fuel injection it is and extra zillion sensors to pay attention to!
Stay carby!
// Meditation doesn't mean you have to sit still....
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Im back
Soo about the ignition coil test, do you want me to test primary coil (power pin and bolt hole)? If so the reading is 0.2ish, the termials do need a clean tho as they are a bit rusty.As for the harness it does not exist 😭
The bikes wires are all taped up by previous owner, not sure if thats a good thing or a bad thing as they are taped up good so i doubt water will get in em. I believe the bike was left outside for some time in winter by previous owner and there are signs of rust in some places and some connectors are a bit rusty, the fuel tank sensor has rusted out completely no reading from it (bike shows full fuel on gauge). This bike is a 06 with high mileage, i dont know the exact mileage as it has been tampered with in the past, at one point it had 30k then straight to 0 then to 20k now at 23k on the odo, so it has been used alot and by age probably falling apart but should be fine, hopefully.There was a video uploaded to YouTube, someone selling my exact bike 13 years ago, which i found interesting as apparently it used to have a alarm system installed.
Still has the fuel tank dent
And fairings are in ruff shape without paint.
Still waiting for the stator unit should arrive by the end of the month. -
Im back again, so I’ve installed the stator unit hooked up the wires yet still no spark.
But as I was moving stuff around a wire from cdi unit just flicked out as if it was in there but not connected, I believe it leads to killswitch but not sure, it one of the wires of the dual connector on the cdi unit I’ll upload a pic here
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This topic should help verify the CDI has the correct wires going in to it.
Needing a little help with my current project (+GT125 CDI PIN OUT)
Regards
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Hi so I had a look and yes the wire does go in the place I presumed it would, but I’m not sure what it’s for, on wiring diagram it goes to “Engine Stop” and to a photo I seen on the forum apparently “12v ignition” it’s the orange and black wire that goes into the 2 wire connector in the middle of cdi, the wire next to it is black and yellow wire, I was wondering what this wire does and how can I test it before I put it back together as it looks abit burned. Thx
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Oh I see, so this could be the issue, I tried pushing it back in the connector while cranking yet nothing. Any way to test it before i fix it up?, as I have a feeling it may be damaged.
Follow the orange way all the way to the front of the harness and test with a meter for a breaks , as a possible short somewhere that’s stopping the electric flow reaching the CDI
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So ive followed the orange and black wire that was broken and it connects to right handle switches. I tested the wire to the nearest connector and got a reading/continuity. I then repaired it (new 2.8m spade connector). Now after installing cable, still no spark. All the switches on the rh seems to work, killswitch stops the starter, starter button cranks the engine, and headlights work. Im not sure on what to do now?. Do the switches need further testing?.
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So ive followed the orange and black wire that was broken and it connects to right handle switches. I tested the wire to the nearest connector and got a reading/continuity. I then repaired it (new 2.8m spade connector). Now after installing cable, still no spark. All the switches on the rh seems to work, killswitch stops the starter, starter button cranks the engine, and headlights work. Im not sure on what to do now?. Do the switches need further testing?.
Coils (are they new?) ==> Check the Plug cap wire is not broken (stops the signals going to the plug)
Stator Unit (wrong one ordered?) (yes it does happen!)
Side Stand Switch = If bypassed, check again. Trust me, even crud under the tape will turn the CDI off from sparking the coils.
Clutch Switch = would NOT recommend bypassing it as “fake neutrals” can happen and bike falls down as soon as you press start , ask how i know!
If the switch is gone, its a quick cheap replacement.Now right there above ^ are what would stop your sparks.
Get a friend to push you down the street ==> Drop to 1st gear , if the bike won’t start from a push & bump, then its defo the above ^
Harness = I will assume you’re going over it like a fine tooth comb where no single wire going to CDI has a breakage. Even the wires for the coils (see link i gave above for CDI layout)
Worst enemy is CDI replacement.
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IT FINALLY SPARKS!!
I decided to have a look at the black and white wire connecting to cdi labelled ground and it was pretty rusty and bad connection when hooked with multimeter to fuel gauge, after cutting and replacing the connector, THE BIKE NOW SPARKS, thank you for helping me fix this issue with my hyo (might not be the only issue as i bought this bike as no spark, so havent tested beyond that)
Regarding the uprated regulator i bought of hyoriders shop, i cant get it to fit even when moving the wiring out of the way, prob just gonna use the old one as the new is massive.
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Make sure the plugs face the back tyre.
So that rain from above ^ or rain water from front tyre < ==> isnt trying to rust up your plugs.
The shop did say the regs will be a monstrosity and said “get creative” fitting.
Go back to the shop and look at the customer galleries for correct fitment , grounding to frame isn’t needed , don’t cut anything! – super strong zip ties help too.
Hyosung in 2020 onwards put their update regs UNDER REAR TYRE! (good for cooling but man , they get wet fast!)
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If the bike kills a massive reg within the 1st ride, we have a problem! = Check all electrics and test your stator (can’t stress it) , if the stator is wanning, your massive reg will pop.
The “teeny” grey one was discontinued & re-called by hyosung as it was causing fires.
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Hi a update on the 06 gt125r
After getting spark i gave her some fuel and cranked, only ran when full choke and full throttle and like 10s of cranking, once idle for a bit then would rev up perfectly but would cut out after some revs when trying to idle again. Decided to clean up carb, once carb was clean reinstalled and tried cranking wouldnt start up… the fuel mixture screw was tampered with before so i decided to give it 2.5 out and cranked it, the bike started first try without use of throttle and was idle good, but when id try give it revs it wouldnt budge unless i held the throttle open for about 5s then it would rev up and rev up perfectly and then idle, but after 2m it would cut out and not start again it would try but wouldnt be able to, i checked the battery and charged, now after multiple attempts apparently this bike will only start at 13.2v and it always cuts out at 13.07v like always at that number, at first i was thinking it may be the carb but after searching online apparently the battery could also cause issues like bike not reving up (mine does rev up but needs throttle on for a couple secs). As the bike only starts at 13.2v and not at 13.07v guessing the battery is at fault and needs replacing?, will buy YUASA YTX 14BS battery as a replacement.
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Keep us posted.
Your old battery may not be holding its juice very well (weak cells inside despite whatever voltage it says) , a fresh YUASA is advised yes (make sure it’s a genuine one from Halfords or TanyaBattery on ebay , other sellers selll either fakes or very old stock!) Time stood is the battery’s enemy, so the fresher the better.
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Just had the new battery installed, and now she can crank for longer before battery dying, but… now she wont start up first time, i got her started by spraying some ez start in intake. She ran and kept running but anything under 3k revs she dies, does rev up good, responsive revs, after running for a while i turn the engine off and after that engine wont start, i tried spraying more ez start but that wouldnt work, after waiting for like 10-15m i then spray some ez start again and try and she starts and same thing under 3k she dies, i tried cranking with throttle quarter open half and full yet nothing choke down nothing, engine does sound like it wants to start but cant catch on fully, last time the engine was able to idle and after holding throttle for 5s delay it would rev then die when trying to go back to idle, but when originally cranked would idle at 2k, now the thing thats linked to idle would be pilot jet and if blocked it would die at idle right?, but bike should still start if i opened throttle? And the fact that the bike will only start with ez start after leaving it for a while. (Btw did clean carb Before).
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Not just the pilot jets clogged, but remember the “Permanent Jet” that is next to it? That is for starting and nursing her to idle back to Pilots. Those 2 cannot be blocked and including the passages inside the carb itself.
If the Pilots are clear, but also use Compressed Air with a straw, spray every little hole you see inside the carb until you can hear swooshing inside (pathway now clear)
Remove the intake manifolds -> Replace the o-rings (These little bastards) make the bikes hard to idle if they even so much as let some vacuum escape under there
If the o-rings are new -> Try to fully clean the surface where they sit so it’s 100% smoothed out. use a PLASTIC toothbrush and scrub hard (no wire brush!)
Then use a little bit of Engine Oil to dress up the o rings wet and install them back.
When it runs , spray carb cleaner around that area to see if revs rise again, then you may have some kind of crack on the intake pipe itself.
AirBox = Front Carb on front Cylinder ==> Check the airbox has fully consumed the front carb, if you see silver lip (carb top rim?) sticking out, there is your future idle problem there.
Final checks, make sure when its hot, do a compression test. I believe it really needs compression checking now.
Let her warm up 10 mins.
Both Spark Plugs out
Full Throttle
Crank It for 5 seconds
Get readings for each cylinder and let us know.I went all over the place in my reply but i hope i made sense.
// Meditation doesn't mean you have to sit still....
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Sprayed carb cleaner on intake pipes and had a look around and nothing, vacuum seems fine over there, Opened the carb up, sprayed air into every hole, removed jets sprayed air in there, everything seems clear, closed carb up and tried starting her, wouldnt start sprayed ez start in intake and she started and kept running, randomly started reving up high to about 7k then to 9k then back down and then again, i let the bike do its thing for a bit as long as it leeps goong back down and not hanging at a high rpm eventually it started going back to 2k but then would rev back up to 3-4k by itself, after waiting for a bit it shut off, wouldnt start unless i used ez start and after getting the engine running again it would only idle at 3k rpm and would die at any under just like before, still waiting on the compression tester to arrive. As the bike was randomly reving up it drank decent amount of fuel the fuel filter usually full of fuel as i look at it, now only quarter full even when bike running.
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Im back with some mixed info on the bike
Soo compression tester arrived today soo got the bike started with ez start but died within 2m i checked the fuel filter and all fuel was drained from it. So at this point it looks like a fuel issue cuz no matter how much i crank fuel filter is same, so i decided to take of the suction pipe on put my finger on it, it was sucking air or something, a bit on the low side but i wouldnt know how strong the suction is suppose to be, i then took off the tank, and hardly any fuel was dripping from it. I then blowed into filter and could hear clear passageway as in i could hear air go around past filter, i then sprayed ez start in intake again and now starts up like everytime without tank with ez start, now gonna get new fuel lines (seen some on hyoridershop), already have a spare fuel filter. Now how do i go with cleaning the tank properly and clear any blockage?. Also one of my spark plugs the rear one center of it is white, front is tiny bit white. Now the other part, i wasnt able to keep engine running for 10m but ran for about 2 or less at 3k rpm engine was warm but not hot, i then removed both spark plugs, tank is off aswell and cranked on rear i got 75psi and front 65psi throttle on full, now the tester i got is a cheap one from ebay and the thread isnt long as in the thread length is only a quarter long so sits higher then a spark plug. So i don’t know if the reading is correct and the last thing i want is less compression, as the cost would be a lot and i dont think it would be worth it as i bought this bike with my fist paycheck at this job i got around the time so i could use it as a fun commuter bike, it has 23kmiles which is not that bad but it is what it is, is there any other way of testing this? Or confirming, as remember the bike did run at idle and would start up first time not long ago and would rev up nicely if i held the throttle for a couple of secs, and even now with ez start it starts up fine. Compression issue is what i feared after buying this bike really hoping it aint.. -
Did you test the compression again one more time please and use the “METAL Pole” like this:
Use the Straight one with the curvy rubber tip, and press down hard on the spark plug hole.
Tell us the compression (even cold, although “hot” would be prefered as per OEM ) with full throttle and both plugs out.
Do this with a fully charged battery
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I think its time to rebuild the front cylinder
At minimum, you want around 125 PSI
Hyosung says the limit is 110 psi hot and healthy range is 140 – 175 psi
Here is a cheap front barrel and piston, it should be OK
https://www.ebay.co.uk/itm/256864818680And here is a spare one
https://www.ebay.co.uk/itm/255751060887I have confidence that either of the above will finally get the bike running.
Ofcourse make sure to get new gaskets you see on this shop
Rear is already at the limit of 110 psi but… If you have to do the rear, then check these out
https://www.ebay.co.uk/itm/256513929819Hyosung Korea isn’t making new pistons for carb 125cc or rings.
I am slowly researching and soon will test custom piston rings off another bike that may fit our bikes. If you just want piston rings, then i think you should email me , but stock is rare now.
This is why you can’t idle, the compression is too low.
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Hmm interesting, the engine was cold when these test were conducted as fuel tank is blocked, is there a way of finding what the exact issue is? And could it be something as simple as valve clearances?, now for this bike i did buy it knowing the risks as it is high mileage and still want to get it running. Now regarding piston rings, couldn’t find any specific for my hyo and would probably be expensive, how would I go around my engine diagnosing this compression issue?, 1 way is to strip it completely, but would take some time.
On the side I will also have to clean the tank ask it did have rust before, not really sure what to use to clean it?
New hoses, already new filter but might aswell switch it out. -
There is a few youtube videos on guys with very old suzukis as they still had metal tanks, some use vinegar, some use white spirit combinations and there was a product used to clean car tanks (metal tanks of old 20th century cars) but keep forgetting the name of it, some also use metal marbles and shaking the tank all day , then using magnet sticks to scoop out floating rust after the fluids have drained out. There is many ways to do it , just make sure the tank is fully dried out but if liquids touch the paint, be ready to cry and likely go to the bodyshop to get it resprayed properly.
Compression Loss as per manual, so i will quote it from the horse’s mouth:
Low compression pressure can indicate any of the fol
lowing conditions :
●Excessively worn cylinder wall
●Worn-down piston or piston rings
●Piston rings stuck in grooves
●Poor seating of valves
●Ruptured or otherwise defective cylinder head gasket// Meditation doesn't mean you have to sit still....
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