Reply To: Midrange lack of power GT125R

[♠️ M77]

Front Plug is oily on the threads , i would be looking to check:

• Have the valve stem seals ever been changed ?  *(if the valve seal is worn out, it could drip oil in the combustion chamber during revving up =  bit of smoke puff on exhaust, it would smell a bit oily, but its a faint hint!) * Check history of that engine if the valves ever got service at all.
  Try this bottle “ONLY!”  (ignore everything else!)
  As it states it is safe for “carbs” and “motorcycles” , Wynns is a trusted brand
  https://www.halfords.com/motoring/engine-oils-and-fluids/fuel-and-oil-additives/wynns-lead-substitute-with-fuel-stabiliser-118855.htmlFollow instructions on the box, then generally ride with a half tank of E5 with that product  (mix the correct amount! = As half a tank is about 8L ish of E5 fuel)
• Check oil level , every 20-50 miles and see if its going down
• Check oil level as above ^ but check if its getting dark & darker quickly  (if it was  having oil change today)
• Use strictly Motul 7100 – most recommended oil for the 125 Hyosungs and its a high heat oil due to fact our 125s have small oil coolers
• Invest in a Gt250 EFi oil cooler. It will thank you a lot.   Do not bother getting chinese coolers , you want the oil pump happy. I’d trust Korea on their coolers this time!

 

If i am wrong ?   Is that wet plug “FUEL” ?  — If its wet fuel , then ignore what i said above ^

If it is WET FUEL

• Service the carb and yes check your floats
• Replace the floats , float seats , float needles – So the bike isn’t jamming (while riding) or flooding the cylinder (while riding or overnight standing as it drips out of the carb in to the manifolds then piston chambers)
• Open the “OIL FILLER” cap –> Sniff hard for fuel , if there is fuel smell that is strong , don’t ride it and change the oil.
• Replace the filter  , i would mandate this tbh.

 

 

While riding === I need to ask?

• Do you hear “popping sounds” in the airbox as you rev up while riding ?
• Does it pull back hard, then slingshot forward ?
• Or does it bog down while riding as revs go up , but only “smooth ride” is during very low speeds ?

 

 

I want to ask more but let’s address the top first so we build a proper picture

Let us know everything I just said.

 

 

 

PS. Glad the caps work for you , that’s why we all use them 😉 – Gotta love NGK caps!