Dong Fang DF 250 RTB Bobber Information

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Originally Posted by Roadkill

I just assumed that Dan was talking about the bobber, but his recent post says that he drives a different bike. Maybe it's lighter, or has a different transmission. Might be his will do what he says. Don't they make s streetbike version with the same motor?

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All the same engine...
As for weight, I had my gf take a spin, she's like 105, far less than Dan
I would believe compensates for the different bike game, if any.

I've not read about anyone with his bike achieving what is claimed anyway, though they don't have a forum to make it known...


I also once had a 35# hunk of metal in my back pack, didn't notice much of a difference otherwise...
And this is because at highway speeds the primary factor is overcoming wind resistance not the delta of already moving mass...

I'm going to look at the chain/ratio discrepancy... Occam's razor...

1 more thing to concider , my butt is not even knee high off ground , with legs near straight out , thus about foot closer to the ground than u guys and thus less air resistance

but im not saying don't change chain and sprocket , if u have the cash burning a hole , 1 to 1.5 hp , gained from chain swap on a 10 hp motor can be significant , like another 6-7 mph

but do note , article was a 1000 ninja (so less gain to be xpected), but it did say 530 to 520chains not the much more drastic (520 to 428 hd) I use

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Originally Posted by Roadkill

I just assumed that Dan was talking about the bobber, but his recent post says that he drives a different bike. Maybe it's lighter, or has a different transmission. Might be his will do what he says. Don't they make s streetbike version with the same motor?

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As you can see from his photo, Dan has a different bike but has the same 167fmm engine as our DF250RTBs. The engine is used in a lot of different Chinese bikes. There is a 270cc version but unfortunately it is not EPA certified.

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Originally Posted by DanDaMan

1 more thing to concider , my butt is not even knee high off ground , with legs near straight out , thus about foot closer to the ground than u guys and thus less air resistance

but im not saying don't change chain and sprocket , if u have the cash burning a hole , 1 to 1.5 hp , gained from chain swap on a 10 hp motor can be significant , like another 6-7 mph

but do note , article was a 1000 ninja (so less gain to be xpected), but it did say 530 to 520chains not the much more drastic (520 to 428 hd) I use

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The gain of 1 to 1.5 HP in the test was on a 118 HP engine .

Using the same ratio on a 167fmm, the gain would be like a .1 to .15 HP increase.

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Originally Posted by barnone

As you can see from his photo, Dan has a different bike but has the same 167fmm engine as our DF250RTBs. The engine is used in a lot of different Chinese bikes. There is a 270cc version but unfortunately it is not EPA certified.

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Off Topic - Deleted by Roadkill

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Originally Posted by ben2go

My GS is 9.5:1 and 175psi is what it puts out when warm.A compression check needs to be done on a warm engine.Any problems that maybe there when running, can go away when the engine cools and the metal tightens back up.

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She's running really nice now but I was concered about the valves so I ran compression this AM. She cranks up 162 psi. Steady climb in about 3 - 4 revolutions. Repeated 3 times with same results. This is with the engine warm, valves set at .002 and .004, choke off and throttle wide open. I was worried about valve damage. Not so much, now.

Checked the plug while I had it out. She is running a little lean so I need to mess with that some.

My set-up: 2012 B model, performance CDI with 4 degree advance, performance coil, Iriduim plug gapped to .028, 30mm Mikuni VM carb with stock needles and jet needle at highest setting, EPA crap removed and plugged, Stock size air filter without the crankcase breather fitting, 35T rear sprocket.

The total cost of all mods was about $100 - 125 and I now have spares for everything.

I have one of those performance CDIs which I haven't installed. Need to figure out some sort of test before and after to see it it does any good.

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Originally Posted by barnone

I have one of those performance CDIs which I haven't installed. Need to figure out some sort of test before and after to see it it does any good.

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Mine feels a little stronger at mid-range. Maybe because it's supposed to have the advance in that range. Maybe it's just a placebo. I live in town and don't really have a place to check top speed. Keep hitting traffic lights. I had one on my trike and had kick back problems on start. I've seen them with adjustable advance.

good to here your resolved roadkill , if ever heading to Austin shout out ill meet ya somewhere let ya see my moped in action

You really should take him up on that offer... It's not every day your invited to witness the world's fastest 167FMM...