Ok guys I'm new to the 4 stroke world I have a few questions like is it normal for them to get warm quick like heat on the engine when u touch it mine hasn't been ridin in a year so I got new oil oil filter and spark plug anything else I should Faldo besides gas by the way my bike is a 05 rmz 250
RM-Z250 New to a 4 stroke
- Thread starter justincr250
- Start date
James
Staff member
The 04-05 rmz/kx250f's are notorious for overheating, I'd recommend using Engine Ice coolant and not let it sit idling for too long. A 64 oz container will be enough coolant for a drain/fill and plenty extra for top-offs. http://www.motosport.com/dirtbike/ENGINE-ICE-64-OZ
I'd recommend checking your valve clearances.
https://www.dirtbikeaddicts.com/threads/checking-valve-clearances-2005-kx250f.4199/
The key thing in keeping your 4 stroke running smoothly is maintenance. Clean your air filter and change your oil religiously. My air filter gets cleaned after pretty much every ride and the oil changed after ~3 hours.
I use the Rotella T oil which you can pick up at your local Walmart/Sam's Club. $3.6 per liter compared to the $9-12 the mx industry brands charge. http://www.walmart.com/ip/Rotella-T-15W40-Motor-Oil-1-Gal/14958327
I'd recommend checking your valve clearances.
https://www.dirtbikeaddicts.com/threads/checking-valve-clearances-2005-kx250f.4199/
The key thing in keeping your 4 stroke running smoothly is maintenance. Clean your air filter and change your oil religiously. My air filter gets cleaned after pretty much every ride and the oil changed after ~3 hours.
I use the Rotella T oil which you can pick up at your local Walmart/Sam's Club. $3.6 per liter compared to the $9-12 the mx industry brands charge. http://www.walmart.com/ip/Rotella-T-15W40-Motor-Oil-1-Gal/14958327
James
Staff member
Cheap hoses will work.
Check the rubber gasket for tear/damage but it is reusable. The cylinder gasket is a one time use gasket, but you won't be removing it until you replace the piston. Speaking of which, any idea how many hours are on this piston? You might want to just replace it as a precaution, they're pretty cheap.
Oh and buy an hour meter, you'd think that you'd be good at guessing but trust me you'll be way off.
Everything James said... BUT I wouldn't go cheap on the hoses spend a little more money and buy motohose hoses.I had an 07' kx250f and I bought some cheap colored hoses but they started cracking after very little use. On the 04-05 kx/rm's most engine builders suggest to change the timing chain and valve tappets/buckets on a routine engine check basis. I would do everything James suggested, but at least throw in a new timing chain and spend a little extra for good radiator hoses... 
ok I have no idea on the hours but I'm going to do a ride or 2 before taking it apart but I figure what I payed for it I'll be good with putting a new piston and what notCheap hoses will work.
Check the rubber gasket for tear/damage but it is reusable. The cylinder gasket is a one time use gasket, but you won't be removing it until you replace the piston. Speaking of which, any idea how many hours are on this piston? You might want to just replace it as a precaution, they're pretty cheap.
Oh and buy an hour meter, you'd think that you'd be good at guessing but trust me you'll be way off.
James
Staff member
Like D8K said, when you do replace the piston make sure to also replace the cam chain.
Are you saying, Now me and the mad scientist gotta rip apart the block, and replace the piston rings AND timeing chain you fried?
yes. but feel free to use blue rtv for a head gasket.