KX Riders

Maintenance & Technical => KX250 / KX125 => Topic started by: GRARA on September 14, 2015, 08:52:03 AM

Title: New piston
Post by: GRARA on September 14, 2015, 08:52:03 AM

Quick question.....Ive just fitted a new piston to my 98 KX250,Ive fitted a larger piston than the last one that was in it because there was too much play....ive ran the bike in correctly but it gets spluttery at high revs and doesnt seem to have the same power...do i have to play around with the carb now that its got a slightly bigger piston?

Title: Re: New piston
Post by: Candyman on September 14, 2015, 04:27:27 PM

Wow.... where to begin....
How did your bike run before the piston replacement?

Title: Re: New piston
Post by: GRARA on September 14, 2015, 10:08:29 PM

Bike was running absolutely spot on...no problems whatso ever

Title: Re: New piston
Post by: Candyman on September 15, 2015, 02:53:34 AM

How much bigger is the new piston?
Did you have the cylinder plated, sleeved, or bored?

Title: Re: New piston
Post by: Foxx4Beaver on September 15, 2015, 07:31:06 AM

ring end gap...piston to cylinder clearance, were these checked?

Title: Re: New piston
Post by: Motorrad on September 15, 2015, 08:26:55 AM

Quote from: Foxx4Beaver on September 15, 2015, 07:31:06 AM

ring end gap...piston to cylinder clearance, were these checked?

+1

Title: Re: New piston
Post by: GRARA on September 15, 2015, 09:30:53 PM

right here goes......i removed my barrel yesterday and found that part of the powervalve system (the flappy bit you can see when you remove the exhaust) has been hitting the piston!!!! Not sure how this is even possible. Ive further been told that my barrel needs a re-plate.
The new piston ( i think ) was a size C?