DF250RTG Stalling Issue

Indianaman · 09-21-2019, 02:49 PM

I just got my first motorcycle, a Dong Feng DF250RTG. I have been browsing this forum and other for over a year learning everything I can before pulling the trigger on a China bike. That said, I have had the bike for about a Week and have put only about 20 miles on it. My only mod to date is that I installed a cool little digital gauge because the OE gauge didn’t have a tach.

My issue is that the bike stalls seemingly once it heats up or after about 10 minutes or so. I just changed the oil to Rotella t4 15w40 and adjusted my valves to .04mm on both the intake and exhaust side but that didn’t make a difference. It is a 165fmm OHC engine wich is seemingly less common on this forum (and difficult to find info on) and comes stock with the PZ30 carb. The only thing I have adjusted on the carb is the idle screw wich is set to 1500rpm. I know that the bike is running a little rich right now due to carbon fouling on the spark plug.

Does anyone know what my issue could possibly be? Any and all help is extremely appreciated. Thanks in advance!

**JerryHawk250** · 09-21-2019, 03:43 PM

You will need to gain access to the idle mixture screw and adjust it. It is hidden under either a brass or plastic cap on the bottom of the carb. It can be drilled out.

Indianaman · 09-21-2019, 04:19 PM

Do you know of a good baseline adjustment to start off at?

Indianaman · 09-21-2019, 07:24 PM

I drilled out the idle mixture screw, mine had an aluminum plug covering the screw, and adjusted it to 1 1/2 turns out and now the bike runs without stalling. Thanks so much for the tip! I am going to be ordering heat soon to fine tune the carb. Thanks again!

culcune · 09-21-2019, 10:47 PM

You adjusted the valves, so one thing to cross off. Do you have the choke on the proper setting (don't ask how I know that one

)? Where it should be set to 'off' can sometimes be confusing on Chinabikes. Did you put in a new (quality) plug? The stock ones can be crappy. Ask Barnone on his thread for his advice if you haven't already done so since he has the same bike.

Edit: didn't read down far enough, so good thing you solved it!! Jerryhawk is good at diagnosing!!!

I would still suggest a new plug if you haven't already done so.

Indianaman · 09-23-2019, 12:27 PM

I did replace the spark plug with an ngk 2202. I am aware of the choke (located on the back of the carb under the gas tank). It has 3 positions: top-full choke, middle-half choke, down-no choke.

I am really having a blast with the DF250RTG. Really my only gripe with the bike is that past 40mph it seems vaguely unstable. I'm not sure if that is due to my lack of riding experience, cheap factory tires, or how light the bike is?

Does anyone know how to get more stability out of these motorcycles? I am thinking about upgrading the rear shock absorbers to the 320mm RFY's from amazon that are air AND preload adjustable. The factory shocks are very stiff and don't seem to dampen bumps in the road very well. Does anyone have any experience with those shocks?

09-21-2019, 02:49 PM	#1
Indianaman Join Date: Sep 2019 Location: Georgia Posts: 62	DF250RTG Stalling Issue I just got my first motorcycle, a Dong Feng DF250RTG. I have been browsing this forum and other for over a year learning everything I can before pulling the trigger on a China bike. That said, I have had the bike for about a Week and have put only about 20 miles on it. My only mod to date is that I installed a cool little digital gauge because the OE gauge didn’t have a tach. My issue is that the bike stalls seemingly once it heats up or after about 10 minutes or so. I just changed the oil to Rotella t4 15w40 and adjusted my valves to .04mm on both the intake and exhaust side but that didn’t make a difference. It is a 165fmm OHC engine wich is seemingly less common on this forum (and difficult to find info on) and comes stock with the PZ30 carb. The only thing I have adjusted on the carb is the idle screw wich is set to 1500rpm. I know that the bike is running a little rich right now due to carbon fouling on the spark plug. Does anyone know what my issue could possibly be? Any and all help is extremely appreciated. Thanks in advance!
	0

09-21-2019, 03:43 PM	#2
JerryHawk250 Moderator Join Date: Oct 2016 Location: Houma, La. Posts: 11,713	You will need to gain access to the idle mixture screw and adjust it. It is hidden under either a brass or plastic cap on the bottom of the carb. It can be drilled out. __________________ 2024 Linhai 300 ATV 4x4 2023 Lifan Lycan 250 Chopper 2023 Venom Evader 2022 Lifan KPX250 2020 Kawasaki Vulcan S (Sold) 2004 Honda ST 1300 2016 Black Hawk 250 (sold) Keihin PE30 carb,125 main,38 slow.Pod filter,ported & decked head 10:1 CR,Direct Ignition Coil,15/40Sprockets,NGK DPR8EIX-9,De-Cat,Dual Oil Cooler,Digital Cluster 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel
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09-21-2019, 10:47 PM	#5
culcune Join Date: May 2006 Location: Yuma, Arizona Posts: 9,056	You adjusted the valves, so one thing to cross off. Do you have the choke on the proper setting (don't ask how I know that one )? Where it should be set to 'off' can sometimes be confusing on Chinabikes. Did you put in a new (quality) plug? The stock ones can be crappy. Ask Barnone on his thread for his advice if you haven't already done so since he has the same bike. Edit: didn't read down far enough, so good thing you solved it!! Jerryhawk is good at diagnosing!!! I would still suggest a new plug if you haven't already done so. __________________ "They say that life's a carousel, spinning fast you got to ride it well..." TGB Delivery Scooter 150 TMEC 200 Enduro--carcass is sadly rotting in the backyard
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09-21-2019, 04:19 PM	#3
Indianaman Join Date: Sep 2019 Location: Georgia Posts: 62	Do you know of a good baseline adjustment to start off at?
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09-21-2019, 07:24 PM	#4
Indianaman Join Date: Sep 2019 Location: Georgia Posts: 62	I drilled out the idle mixture screw, mine had an aluminum plug covering the screw, and adjusted it to 1 1/2 turns out and now the bike runs without stalling. Thanks so much for the tip! I am going to be ordering heat soon to fine tune the carb. Thanks again!
	1

09-23-2019, 12:27 PM	#6
Indianaman Join Date: Sep 2019 Location: Georgia Posts: 62	I did replace the spark plug with an ngk 2202. I am aware of the choke (located on the back of the carb under the gas tank). It has 3 positions: top-full choke, middle-half choke, down-no choke. I am really having a blast with the DF250RTG. Really my only gripe with the bike is that past 40mph it seems vaguely unstable. I'm not sure if that is due to my lack of riding experience, cheap factory tires, or how light the bike is? Does anyone know how to get more stability out of these motorcycles? I am thinking about upgrading the rear shock absorbers to the 320mm RFY's from amazon that are air AND preload adjustable. The factory shocks are very stiff and don't seem to dampen bumps in the road very well. Does anyone have any experience with those shocks?
	0