2005 rm250

[mgtkr1]

having just bought an 05 rm 250 I have only just had chance to ride briefly owing to work commitments. anyway as a newbie to a 250 (previously an 01 kx125) I have a few questions for those in the know. having warmed up for ten mins I then rode for a few minutes to allow the engine to warm up. on my first wot run it was reluctant to rev out. anyway after my return run up the track it eventually cleared and revved out nicely. the torque/midrange is impressive and will wheelie in 5th off the throttle. I have been doing a bit of digging and learnt that the powervalve is adjustable. what plug would you recommend as I think it has a fairly hard plug in it and maybe the premix was on the rich side. it went well once it cleared though, just that it seems to take a while to clear after its been lugged at low rpm. thanks in advance people

[suzuki son of a bitch]

Lean out jetting. I have the same bike but the spark plugs i use are 30 dollars. I know expensive. But they last for ever. i dont remember the exact spark plug though

[mgtkr1]

ok thanks mate. Im thinking the low/mid fuelling is on the rich side as it will start without the choke. it feel as though it hesitates as it comes from needle jet onto the main after its been lugging at all. it revs nice and clean after that if you don't ride at low revs. is tells me she is rich at the bottom/mid

[mgtkr1]

im really hoping it isn't a power valve related, issue however it clears. if the powervalve wasn't opening would it refuse to rev out full stop or can a fault with the powervalve cause intermittent problems? im hoping its either the fact I had been lugging it and fouled the plug or possibly a bit of dirt in the float boal/affecting the main jet's performance or just that its badly jetted. any thoughts anyone? this is really bugging me. the motor has a relatively recent top end and the y compression and new gaskets kind of back this up. is there any other issue to look out for? is the tps prone to playing up?

Edited April 21, 2014 by mgtkr1

[suzuki son of a bitch]

Do you have any bottom end at all? Sounds like jetting. take your pilot and lean it out by going down the next size. And raise the clip up on the neddle one notch. That should work. If not then the power valve could be gummed up. I think its just jetting

[mgtkr1]

thanks. yea the bottom end power is there allright, it will lift the front in 5th once its warmed up ect. just doesn't sound like its revving very high when I try a wot run although it clears and begins to sound crisper. the bottom end power I have to say is imprseeive

[mgtkr1]

just wipped the tank off to change plug. the screw on fitting on the plug was very loose and I was able to push the plug cap back onto the lead some more. hopefully it was just breaking down at higher revs and its solved. I will try it after.

[paddymotodaddy]

I went through the same thing. Thought i had a bad coil

Measured the resistance of the coil wire and it was high. I cut 1/4" off the end and replaced the plug cap. Problem solved for $8.

[mgtkr1]

thanks paddy, im assuming you mean the ht lead were the cap pushes on? what caused that then, was it just a case of dirt/wear n tear compromising the performance

[paddymotodaddy]

Yes and the prong that digs into the core of the wire is threaded like a wood screw and twists on. Rightsy tightsy. Use dielectric grease. I think the loose connection arcs and sparks and the heat breaks the assembly down until it fails.

Edited April 22, 2014 by paddymotodaddy