Dong Fang DF250RTG - Page 3

Weldangrind · 11-13-2018, 11:45 AM

Barnone, I suspect you have a cat hidden in that muffler. If so, I bet there's more power hiding in there.

Barnone · 11-13-2018, 11:51 AM

Yep. There is cat in the header pipe. Not going to mess with that now. Also doubt that it would make much difference in power.

**JerryHawk250** · 11-13-2018, 12:11 PM

Quote:

Originally Posted by Barnone

Yep. There is cat in the header pipe. Not going to mess with that now. Also doubt that it would make much difference in power.

From my experience on the hawk it makes a big difference. I would do it after you have it broke in.

Barnone · 11-13-2018, 02:17 PM

Removed the cat on many bikes in the past with little or no difference in performance. Just more noise so I will leave it be.

**JerryHawk250** · 11-13-2018, 03:40 PM

Quote:

Originally Posted by Barnone

Removed the cat on many bikes in the past with little or no difference in performance. Just more noise so I will leave it be.

I guess it's different from bike to bike. Hawk cat was pretty restrictive. It was like pulling a cork. Just removing the cat I had to up the main jets from a 110 to a 115 and the 110 was a little on the fat side with the cat. Porting the head opened it up even more. From looking at the picture I really don't see a cat in the header unless it is in the muffler itself.

Barnone · 11-14-2018, 09:19 AM

The owner's manual has a photo that shows that cat in in the header pipe close to where the muffler is so I will leave it be. The engine has a decent sound that I am surprised passed ETA.

The engine is a 165fmm Honda OHC CB250 clone at 223 cc.

The valve adjust adjustment clearances on the metal tag on the frame show a value of .02-.04 mm for both valves.
Does that seem right?

**JerryHawk250** · 11-14-2018, 10:25 AM

Quote:

Originally Posted by Barnone

The owner's manual has a photo that shows that cat in in the header pipe close to where the muffler is so I will leave it be. The engine has a decent sound that I am surprised passed ETA.

The engine is a 165fmm Honda OHC CB250 clone at 223 cc.

The valve adjust adjustment clearances on the metal tag on the frame show a value of .02-.04 mm for both valves.
Does that seem right?

I'm sure the CB250 has a less restrictive head and exhaust than the Hawk. .02-.04 mm sounds about right for the CB250.

Barnone · 11-15-2018, 07:51 AM

Quote:

Originally Posted by JerryHawk250

I'm sure the CB250 has a less restrictive head and exhaust than the Hawk. .02-.04 mm sounds about right for the CB250.

Do I need an angled feeler gauge to check the valve clearance on the CB250 OHV clone engine? I have straight feeler gauges that I guess could be bent?

**JerryHawk250** · 11-15-2018, 07:58 AM

Quote:

Originally Posted by Barnone

Do I need an angled feeler gauge to check the valve clearance on the CB250 OHV clone engine? I have straight feeler gauges that I guess could be bent?

From looking at your pictures it looks like you could use a straight feeler gauge on the exhaust. Doesn't look like you have much room on the intake side. You may have to use an angled feeler gauge on the intake.

MDStroup · 11-14-2018, 11:36 AM

Oooh! Another CB option. That is great to know. I wonder what kind of speed you can get from her.

Barnone · 11-15-2018, 07:52 AM

Quote:

Originally Posted by MDStroup

Oooh! Another CB option. That is great to know. I wonder what kind of speed you can get from her.

Me too! I won't know for several weeks since I am in the break in period.

MustangMiddle24 · 11-16-2018, 06:31 PM

Quote:

Originally Posted by Barnone

Me too! I won't know for several weeks since I am in the break in period.

What speed are you getting in the break in period and does it struggle to get there? Also are you loctiting everything?

Barnone · 11-16-2018, 07:23 PM

Quote:

Originally Posted by MustangMiddle24

What speed are you getting in the break in period and does it struggle to get there? Also are you loctiting everything?

Owned 50 or more bikes ( British bikes, Japanese bike, Chinese bikes, Russian bikes) over the last 60+ years and never loctited any of them and never had a problem with parts falling off. Seems to have good power but I am not pushing her yet. Also need to check the speedometer accuracy.

Barnone · 11-16-2018, 07:29 PM

Just got the Certificate of Origin and the sales receipt from the seller so will register her next week. Then I can put some kilometers on her.

Barnone · 11-16-2018, 10:42 PM

We shall see when I need to do the first valve check/adjustment. Be a while.

11-13-2018, 11:45 AM	#1
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	Barnone, I suspect you have a cat hidden in that muffler. If so, I bet there's more power hiding in there. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
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11-13-2018, 11:51 AM	#2
Barnone Join Date: Feb 2007 Posts: 1,348	Yep. There is cat in the header pipe. Not going to mess with that now. Also doubt that it would make much difference in power.
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11-13-2018, 02:17 PM	#4
Barnone Join Date: Feb 2007 Posts: 1,348	Removed the cat on many bikes in the past with little or no difference in performance. Just more noise so I will leave it be.
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11-14-2018, 09:19 AM	#6
Barnone Join Date: Feb 2007 Posts: 1,348	The owner's manual has a photo that shows that cat in in the header pipe close to where the muffler is so I will leave it be. The engine has a decent sound that I am surprised passed ETA. The engine is a 165fmm Honda OHC CB250 clone at 223 cc. The valve adjust adjustment clearances on the metal tag on the frame show a value of .02-.04 mm for both valves. Does that seem right?
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11-14-2018, 11:36 AM	#10
MDStroup Join Date: Apr 2016 Location: Chesapeake, VA Posts: 207	Oooh! Another CB option. That is great to know. I wonder what kind of speed you can get from her.
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11-16-2018, 07:29 PM	#14
Barnone Join Date: Feb 2007 Posts: 1,348	Just got the Certificate of Origin and the sales receipt from the seller so will register her next week. Then I can put some kilometers on her.
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11-16-2018, 10:42 PM	#15
Barnone Join Date: Feb 2007 Posts: 1,348	We shall see when I need to do the first valve check/adjustment. Be a while.
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