Way off topic, YZ-250F starting problems

[dawgfan]

Before everyone gets pissed, I am the proud owner of a Shee!

But I am looking at a 2001 YZ-250F that I can get real cheap and am thinking about buying. The guy says it has a big bore kit, but not sure what size. It's hard as hell to start cold. Most of the time you have to push start it. Once it gets warmed up, you can kick it, but it's a bitch when cold! I'm just thinking it's because of the high compression, but not sure. It runs great, just can't get the thing started when cold. Anyone have any ideas or suggestions on what I should beware of? I don't know jack about 4 strokes, and really don't care for them much, but if it's nothing serious it's to good a deal to pass up. As always, thanks for the help in advance!

[midnite]

When a DOHC motor gets hard to start, it's a sure sign the valves need adjusted [shimmed]. You can get shimms from yamaha, and do it yourself. It's not hard to do.

[THEREALBUDLIGHTBANSHEE]

well i was at keystone last weekend riding,35degrees f,3 or 4 of the 4 stoke bikes would not start they kicked on them for 20 to 30 min,finally got one pull started,the other 2 left,could not get started,i think cold weather and no electric start,makes them a pain in the ass to start up.

[ssanddemon]

The 250F is one hell of a woods and track bike. I would do a compression test, and if that's OK and everything else looks decent, then I would buy it if it really is cheap. It's probably a carburetion issue if the compression is good; although a worn out spark plug and tight valves can definitely cause problems. I just fired up my XR650R in the garage tonite (going to the dunes tomorrow with it and the shee) and it fired up on the 3rd kick at 35 deg air temp.

[jeepman380]

When you were trying to start if did you have the choke on? Not to be a dick but just sometimes you forget. Alot of 4-strokes won't start in the cold without the choke on.

[dawgfan]

Yeah, choked or not, it's just a bitch to start the first time. After you get it running though, runs great and fires back up easily in a kick or 2. He just had the bottom end completely gone through, and had the big bore kit put on it so was thinking it was just a tuning issue maybe. Just kinda sketchy about it cause I've never seen one with a big bore kit. The only 4 strokes I've seen with one are a couple of 440 EX's and they didn't seem to be worth a crap.

[dawgfan]

Yeah, choked or not, it's just a bitch to start the first time. After you get it running though, runs great and fires back up easily in a kick or 2. He just had the bottom end completely gone through, and had the big bore kit put on it so  was thinking it was just a tuning issue maybe. Just kinda sketchy about it cause I've never seen one with a big bore kit. The only 4 strokes I've seen with one are a couple of 440 EX's and they didn't seem to be worth a crap.

446988[/snapback]

 

OK, scratch all that, I rode it again today. Would NOT start without pushing. After I rode it for a while it would kick start, but only with the throttle wide open. Seemed to run really good aside from that, but it did have idling issues. Anyone know how much compression it should have?

[ssanddemon]

I would guess around 170 to 190 Psi, although it should start ok with anything over about 120 in the cold. 100 psi is the lowest compression most 4 strokes will run at.

[dawgfan]

I would guess around 170 to 190 Psi, although it should start ok with anything over about 120 in the cold.  100 psi is the lowest compression most 4 strokes will run at.

447740[/snapback]

 

Thanks, thats what I needed to know. I'm gonna have the compression checked and go from there.