ninjette.org - View Single Post - Sluggish rev, erratic idle, dies with throttle

Fappy · October 5th, 2012, 06:49 AM

I've got an issue I was hoping you guys could help me with.

So I have a 2008 Ninja 250. I've been riding it to work basically every day, except yesterday (rained), and have had no problems recently. The bike runs fine. Even took it for a 67 mile trip on Sunday.

Today, I was going to start the bike up to ride it into work, when this occurred:

I smelled gasoline (light, not too strong) around the bike. Ignored it.
Went to start the bike. About 60 degrees out. Choke on full, hit the starter - Cranks for 5 seconds, nothing.
Repeat cranking 5 times, gave the bike some throttle at the same time, and it was able to start. This is highly unusual.
With the choke on full, the RPMs barely climb above 1k.
After a few minutes, the RPMs begin to climb, but it becomes erratic. Idles up to 4k by itself, and then down to 1k, repeating.
Bike has been idling for about 5 minutes in this manner. I go to give it some gas. Very sluggish.
Open throttle about 1/3, and the engine dies.

Even after warming it for about 10 minutes, this problem continued. It revved terribly slowly and if I gave it any throttle beyond about 1/3, it would immediately die. Also note that I was able to get it to idle with the choke off after warm. Seemed to be at exactly 1300 rpm there, which is good.

Changes since I last rode it (two days ago)?
1. It drizzled a little overnight, and the bike was uncovered
2. I put a new chain on last night, but did not remove the rear wheel or change the sprockets (the sprockets were okay.)

16,000 miles on it.
Could the carbs have gummed up overnight? Could something electrical be damp and causing this issue? Water in the gas? No idea!

October 5th, 2012, 06:49 AM	#1
Fappy ninjette.org guru Name: Stephen Location: Philadelphia, PA Join Date: Aug 2012 Motorcycle(s): 2007 Ninja 650R, 2008 Ninja 250R (sold) Posts: 263	Sluggish rev, erratic idle, dies with throttle I've got an issue I was hoping you guys could help me with. So I have a 2008 Ninja 250. I've been riding it to work basically every day, except yesterday (rained), and have had no problems recently. The bike runs fine. Even took it for a 67 mile trip on Sunday. Today, I was going to start the bike up to ride it into work, when this occurred: I smelled gasoline (light, not too strong) around the bike. Ignored it. Went to start the bike. About 60 degrees out. Choke on full, hit the starter - Cranks for 5 seconds, nothing. Repeat cranking 5 times, gave the bike some throttle at the same time, and it was able to start. This is highly unusual. With the choke on full, the RPMs barely climb above 1k. After a few minutes, the RPMs begin to climb, but it becomes erratic. Idles up to 4k by itself, and then down to 1k, repeating. Bike has been idling for about 5 minutes in this manner. I go to give it some gas. Very sluggish. Open throttle about 1/3, and the engine dies. Even after warming it for about 10 minutes, this problem continued. It revved terribly slowly and if I gave it any throttle beyond about 1/3, it would immediately die. Also note that I was able to get it to idle with the choke off after warm. Seemed to be at exactly 1300 rpm there, which is good. Changes since I last rode it (two days ago)? 1. It drizzled a little overnight, and the bike was uncovered 2. I put a new chain on last night, but did not remove the rear wheel or change the sprockets (the sprockets were okay.) 16,000 miles on it. Could the carbs have gummed up overnight? Could something electrical be damp and causing this issue? Water in the gas? No idea!