1992 CR250 has NOTHING after 1/4 throttle HELP

[Crf450r64]

Samething happened to my 400ex and it was accelerator pump

[frdbtr]

Samething happened to my 400ex and it was accelerator pump

92 cr250 doesn't have an accelerator pump.

Before blaming the stator, we need to find out if it is simply a rich jetting issue. I would say to replace the stator side crank seal, check the main jet to make sure it isn't pig rich, make sure the power valve opens when you rev it, and then start thinking about an electrical issue.

[Crf450r64]

92 cr250 doesn't have an accelerator pump.

Before blaming the stator, we need to find out if it is simply a rich jetting issue. I would say to replace the stator side crank seal, check the main jet to make sure it isn't pig rich, make sure the power valve opens when you rev it, and then start thinking about an electrical issue.

My bad don't know anything about that year or 2t just throwing out an idea ha

[donahue_85]

Ok, so I have replaced the stator side crank seal this evening. I started it & revved it, still same thing. I took it for a ride too & I have a tiny bit of bottom end power, but still nothing past a quarter throttle. So it must be something else. I did not check the plug after riding it this time though. It did shut off on me twice though, after I pulled the clutch & slowed down to make a sharp turn around, it died. Seems as if its still loading up?!?! I am getting frustrated with this bike!!!! I guess I will check jetting next......

[heart_of_darkness]

Buy a number 52 pilot jet. That's better suited to your engine unless you're riding in extremely cold temperatures, and eliminates the current jet as a possible problem.

What condition is your air filter? How about the reed valve petals?

Also remove the muffler and shine a light through the interior tube. Sometimes animals build nests in exhausts.

Also the PJ carb is notorous for its choke circuit, which also functions to set the idle speed. When that goes bad, it causes all sorts of erratic running. Temporarily screw the carb's idle knob all the way in, which give no idle. You'll need to keep the throttle grip held very slightly to keep the engine running. See if it runs any more smoothly that way.

[frdbtr]

Buy a number 52 pilot jet. That's better suited to your engine unless you're riding in extremely cold temperatures, and eliminates the current jet as a possible problem.

What condition is your air filter? How about the reed valve petals?

Also remove the muffler and shine a light through the interior tube. Sometimes animals build nests in exhausts.

Also the PJ carb is notorous for its choke circuit, which also functions to set the idle speed. When that goes bad, it causes all sorts of erratic running. Temporarily screw the carb's idle knob all the way in, which give no idle. You'll need to keep the throttle grip held very slightly to keep the engine running. See if it runs any more smoothly that way.

Plugged exhaust. Also a good thing to check +1

[donahue_85]

The exhaust is good & clear.

I'm thinking it must be an electrical gremlin. I mean I've been through just about everything twice over! lol

[223hpyhooker]

With what you already found i would tare the whole top end off and make sure the guy didnt mess anything else up it sounds like a fuel problem lime mentioned jet. Or restricted exhaust my guess broken or gummed up power valve if its locked shut. These bikes rev so quick it dont take much to open when it opens you get the fast raise in rpms, but after watching your video it doesnt even start to rev once you give it throttle idk if reeds would cause this or not.

Edited February 3, 2013 by 223hpyhooker

[donahue_85]

I don't have any experience with power valves other than what I've played with on here. But I do know this, when I manually opened & closed it with my hand, it seemed that everything was moving as it should, but when I looked in the exhaust port while moving the valve, it didn't seem to move much, but again I'm unsure how much it should move to start with. I did check the valve while it was running & it didn't move from off the L (low setting) at all. Even after all the parts I put in.

I will run it again today & make a video to show you how it is running now compared to before I put in all the new stuff. I will also show the power valve & what it does when I rev it up. I know that videos make things so much easier!

Thanks for everything so far, I just hope I can figure this out soon, I'm itchin to ride it!!

Oh, the reeds are like brand new by the way.

Edited February 3, 2013 by donahue_85

[frdbtr]

If the power valve is not opening from the L to the H position as you rev the bike, that is your problem. It may be installed incorrectly. You will probably need to pull your top end and check it out. IMO, you should probably get a factory honda service manual and then reassemble the power valve the way it instructs.

[donahue_85]

I thought about pulling the jug to check everything but I was hesitant about it. But I guess I will, considering I've already tried EVERYTHING else minus the electrical stuff.

But when I start it, it runs fine till about 2,000 RPMs. After that, it seems to load up with fuel & run like ass. The more I run it, the worse it seems to get. But is there a certain RPM that the valve starts to open or like how does it work?

Sorry I didn't get the chance to make any vids today, I'll get them sometime this week! Please keep the suggestions coming!! I REALLY appreciate them!!!!!

[spires34]

jetting issue, like a few others have already said. Have you messed around with the jetting since those suggestions? Im just seeing this convo for the first time, and would like to see if its jets, or if you've already fixed it.

[donahue_85]

I have not changed the jets. All I have done with them is clean them. I have not gotten around to buying any yet.

[kawamaha]

But when I start it, it runs fine till about 2,000 RPMs.

do you know this or guess it?

power valves open at about 4500-6000rpm

if it runs fine until 2000 rpm's, it sounds like a carb or electrical issue.

i don't know the 92 motor, maybe there's a L-H indicator at the left side of the cylinder. if so, can

you turn it with a tool? then you can turn it to H and see if it revs...

[donahue_85]

Yes there are marks on the left side indicator, but no I can't turn the valve with a tool. Is there a way I can check the electrical system with an ohm meter to see if everything is working right? Like I think there is low speed & high speed spark. So the high speed part of the system could be no good? Anybody got specs on this?

[MrN2OBelvedere]

My PV is not working because it won't even rev high enough for it to kick in. Or at least that's what I'm guessing. I was told by a mechanic that it only operates at high RPMs?

I was thinking the same thing about my bike but when I got it put back together I was surprised how fast it actually opens up. It pretty much opens up all the way with a good blip of the throttle at idle. Just revving the engine at idle you should definitely see the PV open and close. If you make this check and don't see the PV moving then you have found your problem.

[donahue_85]

I know there is a gremlin somewhere, I thought I had the PV fixed because I found that the governor bearing that the drive rod rides on was destroyed when I pulled it apart. So I replaced the governor & thought that would fix the problem. But I guess something still isn't working right.

[kawamaha]

on a 1992 motor there are 1000's of things that can cause issues like that...

now that searching for the issue via internet is not that easy, in your case I would do following steps:

remove the cylinder, disable the power valve connection to the gouvernour, fix the power valve in the open (H) position.

I don't know if the HPP only raises the exhaust height at high rpm's or like the KIPS, closes air chambers at the same time

- but make sure the flap (or sliders) are open at H position.

reinstall the cylinder, see if it revs...

[MrN2OBelvedere]

on a 1992 motor there are 1000's of things that can cause issues like that...

now that searching for the issue via internet is not that easy, in your case I would do following steps:

remove the cylinder, disable the power valve connection to the gouvernour, fix the power valve in the open (H) position.

I don't know if the HPP only raises the exhaust height at high rpm's or like the KIPS, closes air chambers at the same time

- but make sure the flap (or sliders) are open at H position.

reinstall the cylinder, see if it revs...

Agreed. If you can force the assembly open without causing any kind of mechanical interference in the PV system then this would be a good troubleshooting idea.

[donahue_85]

Ok, so here is what I've accomplished today. I pulled the jug (cylinder) off & removed the PV & cleaned it up. It is like new now! Everything operates perfectly, as it should. So I went to run it & again, it started, idled fine, but when it is revved, NOTHING!!! It is NOT the PV. It has to either be fuel related or electrical. I am going to perform some carb tests in a day or so & try to verify whether its that or spark. I'll keep you all informed!! Keep the suggestions coming though!!!!!