Engine Rev after Wide Open Throttle?

Discussion specific to the 1991 - 1994 KDX250 sold in the USA
Post Reply
Noj
Member
Posts: 19
Joined: 08:42 am Jul 15 2020
Country: USA

Engine Rev after Wide Open Throttle?

Post by Noj »

I've been dialing on my kdx 250 now this week. Did the standard, 38 pilot, 58 main, #6 slide, 1367h needle, fmf pipe.. and it's whole different bike. It runs great for the most part, but I've noticed after a long stretch of wide open throttle going through gears, when I slow down and pull in the clutch it kind of revs up and hiccups for a second similar to when it's running out of fuel, then is fine.

I'm guessing this means my float is too low? I set it to spec, so I'm surprised ripping this thing open is drinking up what's on the bowl so fast, but it has been consuming more than usual fuel lately which leads me to believe possible bad jet block gasket or the metering brick is just worn out..

Anyone else encounter the Rev up after wot?
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: Engine Rev after Wide Open Throttle?

Post by KDXGarage »

How long is a long stretch?

I'd try to adjust the float height before spending the money. :-)
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
Noj
Member
Posts: 19
Joined: 08:42 am Jul 15 2020
Country: USA

Re: Engine Rev after Wide Open Throttle?

Post by Noj »

Maybe the length of a football field or a little longer.

Well I went ahead and ordered the gasket because the previous owner told me he dipped the carb and I guess you're not suppose to dip them, so it's either the float bowl or the jet block gasket at this point. Nothing else it could be with the newly redone jets, it runs great, just gets weird and revs up after ALOT of throttle like its' running out of fuel or something.

Also at idle it idles slightly up and down.
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: Engine Rev after Wide Open Throttle?

Post by KDXGarage »

A pressure or vacuum issue may need to be checked.
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
Noj
Member
Posts: 19
Joined: 08:42 am Jul 15 2020
Country: USA

Re: Engine Rev after Wide Open Throttle?

Post by Noj »

Yeah. That's why I was thinking it's the Jet block gasket. When there is a leak in that, things tend to get weird from what I read. The boot and air box are fine. No exhaust leaks. Engine is pristine.

I'm guessing because the carb was dipped the gasket is now damaged. I don't know what else it could possibly be.
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Re: Engine Rev after Wide Open Throttle?

Post by KDXGarage »

For $20, replace it. Go from there.
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
Post Reply