Reply To: Running issue 2012 gt125r
Do you have any pod filters on the bike ? and would you say you are using stock CR8E plugs ?
If possible, try and see if you can gather fresh set of CR8E plugs from halfords if they are open now , and go for a short ride when it is safe (ice is on the way!)
Come back, take pictures of the plugs, and show us. This way i can try make a judgement based on how the threads look and how it also looks inside.
So get side view and inside view of the plugs.
Do a compression test again after its hot.
Spray carb cleaner on the rubber intake pipes = did revs change ?
Spray carb cleaner on the airbox rubber openings that swallow the carb (especially the front carb doesn’t always get fully swallowed by the airbox_
Jetting is fine as long as it is 90F / 92.5R and 15 Pilots (both cylinders)
Mixture Screws = Be very careful here as it is easy to round them off. — If you see a _____ dash___ make a mark on the carb, then count down the FULL turns clockwise until it stops , then go back to where it was. Eg. I screwed down the front cylinder, and it was 1 full circle and then half a circle , this means 1.5 full turns downwards or 1.5 full turns from stop to counterclockwise. Least we know what mixture it is.
Mid Range RPM = Have a look at this topic to see if it will help ?
[Tutorial] How to adjust Carb Slide Needle (Tuning) – Hyosung GV & GT 125/250
High RPM = Does it do high RPM at any gear at all (peak power is at 9-10k rpm, so you definitely don’t want to redline those pistons anyway) No more power after 11k rpm as valves start floating and premature wear happens faster. Staying under 10k is good and it will thank you.
Coils = Please report the OHMS readings for the coils (without HT cap attached)
CAPS = are they stock caps ? (problematic!) = 99% of us switch to NGK caps where possibl,e (DO NOT USE PLASTIC NGK caps , they will crack too!) , we use rubber versions, like you see on the site. If not , for a cheap fix, get another good set of stock HT CAPS on ebay from a local UK seller.
HT CAPS OEM = 7-10K OHMS on their own is good. (10 thousand yes max)
Coils = Sorry here is the link to test before i digress!
Rectifier – How to Test Stator , Battery , Regulator – GT125R Carby
Test your stator = Trust me if the pulser/sensor acts funny, so does the CDI and coils, ignition/sparks/timing starts with the magneto/stator.
You got this and happy holidays!