BannedCR500Riders.com

My feet are wore out from chasing tuning gremlins...

Im starting to think ignition...

check for loose grounds.. cuz that didnt sound good at all.. i would also check the stupid switch on the handlebars.. if its shorting out that could lead to something like that too.. but that didnt sound right. didnt sound like jetting to me... Jetting isnt choppy like that usually

I tore the bike down to the bare frame and put it back together right after buying it a few months ago (my usual style) regreasing and torquing everything. Im going to try a new spark plug wire as others have suggested before, first. Whats been throwing me off, making me suspect jetting is the problem is throttle position and rpm dependent...

erratic running like that makes me think ignition. Is that a 250? casuse the 2002+ has 3 d igntion with TPS...... maybe the TPS is faulty?

No jetting issue cuts out like that.

No tps...2004+ only...

ya sounds like ignition parts to me too. Check coil connection 1st. Or swap out..prolly the easiest..

I just need one of u guys to stick Ur hand on the coil wire while I ride around so u can tell me where the bad spots are...

na, run a wire up to your sac, you'll know if it quits for a bit

oh, ok I stand corrected didn't realise 04+.

If its throttle and rpm dependant, I would say its actually load and resistance to ignite,
meaning there is a short with less resistance than the plug has when the motor is loaded up.

I would check the coil ground, secondary side of the coil, wire, cap.
Cut 1/4" off each end of the wire and thread the coil and cap back on if the screws have no corrosion. I like using dieelectric grease to keep the ignition sealed too.

I have heard if there is enough dust on the plug, the spark can travel down the porcelin and ground on the head instead of firing in the hole.

I think I fixed it. The spade connector for the "hot" on the coil was "loose". It seemed to correct the problem but the track we went to was pretty rough and rocky so it was hard to tell for "sure". I'll cruise around the neighborhood and see how it feels when I get a chance. I'm still going to put a new plug wire on it also since the stock one looks shitty...

dubious01 wrote: I have heard if there is enough dust on the plug, the spark can travel down the porcelin and ground on the head instead of firing in the hole.

Dust? On my bike? HAHA You dont know me too well?

M.F.D.B. wrote:

dubious01 wrote: I have heard if there is enough dust on the plug, the spark can travel down the porcelin and ground on the head instead of firing in the hole.

Dust? On my bike? HAHA You dont know me too well?

haha, ok. I mean the black dust from the boot.
seriously i have also heard that using a black marker to index the plugs on cars has been known to provide a path of less resistance, causing the ignition to short to the head down the porcelin!

I certainly can't fault a guy for taking good care of his bike! I'm the same.