Dong Fang DF 250 RTB Bobber Information

**barnone** · 03-23-2011, 06:13 PM

The 33 T sprocket sure looks small compared to the 40 T stock but it did just fine on the ride out to the ranch. I ran it up to 75 MPH indicated (probably 67 or so real) and she had some left but that was enough for me. Pulls good from 30 MPH in fifth gear. Like the lack of vibration at 65 MPH indicated.
Definitely a big improvement over the stock gearing but you might want to try a 35 T to get a 2.69 ratio?

Sure makes first gear a lot more usable.

The chain is a standard 520.

BIG TIME EDIT. I got to thinking that sprocket size difference is just too great and I went out and counted the teeth on the stock DF sprocket and it has 45 teeth. I don't know where we got the 40 teeth size from but no wonder the DF was running out of first gear so quick and only capable of 65 or so MPH with the stock gearing. I need to go back and correct a few posts.

**barnone** · 03-23-2011, 06:50 PM

Just to make sure we are all aware of the correct number of teeth on the stock DF rear sprocket. It's 45 T instead of what we thought.

**Gardo** · 03-23-2011, 08:04 PM

barnone all great stuff, it really was an awesome bike good to know that you can pull some power out of that thumper. How many miles are on her now?

**redrover** · 03-23-2011, 08:08 PM

Originally Posted by barnone

Just to make sure we are all aware of the correct number of teeth on the stock DF rear sprocket. It's 45 T instead of what we thought.

13 front and 45 rear; wonder if they were thinking we'd be entering them in hill climbs? :)

**jape** · 03-23-2011, 08:31 PM

Yeah, that is pretty standard for a China bike, dual sport, so whoever found all those bits in bins in China and put them together in that frame type didn't do much thinking!

It was great on my 200cc kinlon d/s, just what I needed in the mud and bush tracks when you sometimes need to lift a wheel or scoot through a rut. especially with a heavy old frame and wheels. But on th e road after an agonizing few months I had to change and I just don't understand why the 'designers' /cloners in China don't do this job themselves. Every forum in the world, that is the first change we all make! Don't the dealers have any say over this? Daft eh? Maybe they think we all live inside huge metropolises where we want to fang around at high revs all day never getting over 55?

Good to see you got the predicted outcome Vince. I feel on mine that it would go all day at cruise, would love to be able to try it out. There is a sweet point when all the vibes calm down, the engine and exhaust noise seem to harmonise and disappear behind you rather than reverberate in your ear. Strangely, the journey seems faster at that speed than it does when you push it!

**barnone** · 03-23-2011, 10:31 PM

Originally Posted by redrover

13 front and 45 rear; wonder if they were thinking we'd be entering them in hill climbs? :)

red,
Maybe they plow with them in China? Feel kinda dumb that I didn't count the teeth on the rear sprocket but somehow 40 teeth got stuck in my head.
13/45 is the lowest ratio of all my China bikes.
Gardo,
I think I'm about up to 550 miles on her. I try to ride my other two bikes here in FL the same.
Jape,
You hit the nail on the head with your last statement.
"Strangely, the journey seems faster at that speed than it does when you push it! "
She is starting to feel that way.

**jape** · 03-23-2011, 10:38 PM

Originally Posted by barnone

Jape,You hit the nail on the head with your last statement."Strangely, the journey seems faster at that speed than it does when you push it! "
She is starting to feel that way.

I don't know if you are old enough to ever a have been a hippy type, but you have 'found the groove' man! What riding is aaaaall about!