Hesitation off of idle

I have been out a couple of times with my new to me 03 XR250R. I am having one small annoying issue. When I am sitting idling in first gear and I go to twist the throttle, it will hesitate, cough and die. I can get it past that point with a couple of quick twists and then engage the clutch or I can let the clutch into the very edge of the friction zone and then hit the throttle and its ok. This is after full warm up. I pulled the spark, it looks good and its not fouled, so I'm not running too rich. If I run it with some choke, it bogs. That tells me I'm not running too lean, right? The carb has been re-jetted and cleaned. It fires first kick when cold. Any ideas?

Fine tune the fuel screw for best throttle response and idle.

I have the same problem as TJ99. I have an 89 XR250R, is there guidelines for where the fine tune screw should be set at as a starting point?

Riverb8,

There should be guidelines in the manual. There are in mine but it only goes back to '96 so it probably won't apply to your '89.

Start with 1.5 turns out from lightly seated and go from there.

TJ , what mods have you done and do you have any aftermarket parts like a slip on ? What size jets did you go with ? Did you dial the jets in or just slap bigger ones in ? Wheres your fuel screw at ? Did you adjust it after rejetting ?

The carb was rejetted by the shop I bought it from. Don't know what jets they used. I know, I should've asked. The guy seemed to be up on the lean jetting that a lot of bikes have from the factory. It has a white bros E series can. I believe its stock other than that.

First of all the bike does not have an acceleration pump. You can not snap the throttle like on a two stroke but you can minimalize the problem. Be sure the bike is idling about 1000 rpm. Now once the bike is fully warmed up and hot, screw the fuel mixture screw in and out to get highest idle. Out is richer and in is leaner. Once you get highest idle then turn out an additional 1/8-1/4 turn. You are making it richer to take the throttle better off idle. NOW, readjust your idle to about 1600 rpm. This is a fast idle. You don't want a loping idle. I bet your stalling / hesitation problems will be over.

NOW, readjust your idle to about 1600 rpm. This is a fast idle. You don't want a loping idle.

Yep. Everything Dwight said is about as far as you can go with the stock carb in my experience. I still didn't like it & shelled out the bucks for an Edelbrock. Pricey, but was well worth it for me. A shame that XRs didn't come with pumpers from the factory imo. I hated my stock carb.

First of all the bike does not have an acceleration pump. You can not snap the throttle like on a two stroke but you can minimalize the problem. Be sure the bike is idling about 1000 rpm. Now once the bike is fully warmed up and hot, screw the fuel mixture screw in and out to get highest idle. Out is richer and in is leaner. Once you get highest idle then turn out an additional 1/8-1/4 turn. You are making it richer to take the throttle better off idle. NOW, readjust your idle to about 1600 rpm. This is a fast idle. You don't want a loping idle. I bet your stalling / hesitation problems will be over.

Thanks Dwight. I will do that. Just got back from 3 days of riding with my daughter in AZ. Awesome! The hesitation/stalling issue was a little annoying but I worked my way around it. Other than that, the bike ran great. This bike will probably work for me for a long time. Thanks for the info.:thumbsup:

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