Posts
2
Joined
2/24/2024
Location
Central, OR, USA
Hey ya'll, i've lurked here for a while, i finally made an account since i have an issue. I just had a top end done on my sons 2022 KTM 125. It has 70 hours on it. Ive done a couple top ends before, but dont have alot of experience. I have a few other projects taking room in my shop and decided to take it to a local mechanic to do it for me. He seemed really concerned about the condition of the old piston. I wouldn't have thought twice about it and it looks fine to me. He thought i am not running enough oil in the premix, and potentially waited too long for the new piston. I am running amsoil dominator at 40:1. What do you think? Thanks.
Yeah 70 hrs is too long in a 125. I'd shoot for between 25-40 in a KTM 125. Looks like bike is running on the rich side and not getting excessively hot so you should be fine to stretch to 40.
What the heck is this right here? Is that as bad as it looks? Is that raised up and you can feel it?
I agree with FRG01, what's up with the spot, and 70 hrs. on a cast piston in a 125 too much. When all the tiny grooves like you see on the sides of the piston wear off the front and back you're no longer carrying a good film of oil where you need it most and wear accelerates. I would go to a forged piston if you want to push the intervals out. Amsoil dominator at 40:1 should be good.
Thanks for the responses. As far as the spot goes, its just the way the light hits it. There's no ridge there, i cant feel anything and a finger nail slides right over it. I'll lower my service interval next time. Thanks again.
How does the intake side look?
Looks to me like you've had some debris pass by the skirt ... not great for rings or the coating.
Revisit air-filter service routine ... check for holes, improve cleaning and filter oil coverage.
Post a reply to: Piston doublecheck