Dong Fang DF 250 RTB Bobber Information

[axa]

So.. something I do not understand.


I watched several videos of the Heist today. The bike completely stock with just a change to a 38 rear sprocket will do 80 mph... this motor is basically the same as ours.. Is it paired with a different transmission?


Had mine flat out today with all the mods and 35 rear 58 mph.

says who?
you watching this vid ??

I don't live too far from there, its the GSP south.
65 is average, 75 avg in the left lane.
I know it well, and for some reason, slow traffic stays in the center lane. And look where he was the entire vid, center lane with cars passing him from both the left AND the right...

I know what the comments say, hold 65-70, 80 bursts, but i don't buy it. And thats NOT what was going down in the video anyway.
ccw uses a 11.5kw 167fmm just as our does, and no tuning in the world is going to buy much more than that.

he might have been doing 65 but the slow center lane doesn't do anymore than that, but i think we could hold that on a flat with barone or dan's gearing...


and for all i know they may be using an over ambitious speedometer just like ours...

[4950cycle]

Did the rider weigh 100 lbs. ? I had a 16/38 setup that actually made the Chinagirl to high geared for the torque/hp it has. Hell, it would only go about 57 mph. You could tell it just didn't have enough power to go any faster with that taller gearing.

[barnone]

Don't believe everything you see or read on the internet.

That guy in the video is Gordo who exaggerates the performance of the Heist.

And again weight has little affect on top speed. Wind resistance, rolling resistance,and available power are the major limiting factors affecting top speed.

Weight will affect acceleration.

As mentioned previously, the Heist and the DF have almost identical engines. Both are 167FMM engines. I got banned from the CCW forum for telling them to correct their specs to 229cc instead of 250cc.

[4950cycle]

I agree, But because I am 6'3 255lbs, guess what ? The bike has more rolling resistance because I'm smashing down on the tires more than a 100 lbs. rider. And I'm catching a heck of a lot more wind than a normal size 130 lbs. person. Therefor wind risistance comes into play also weather you are tall and/or fat. Again I agree with you. I wouldn't belong to a forum that you really have to watch what you say to not get kicked out. I think a lot less of Cleveland Cycle works now for having heard that. The Hiest must not be that great if Clevland Cycle Works has to stiffle the truth.

[ProDigit]

Wow, I hope this thread isnt going downhill. It is too valuable and I wonder if there is a posting limit on it's size. But I agree that common sense dictates that we stay on topic. Yes there is a search engine but posting about grandma's buick in here isnt helping us DF owners. (just joking of course). Even a search engine has limitations. And lord knows I posted Off Topic on the Enfield here so pot-kettle-black. Guilty as charged.

I only pray that if this thread ever closes somebody will have the knowhow and care as to how to save it in PDF format for download and back reference. At this point I do at least have a txt file I keep for the stuff that concerns me most.

And Ironically I am posting this off topic as well. See what you guys started LOL?

On Firefox, there's an add-on called 'ScrapBook', which you can install, and use to download this whole thread. The whole thread is about 80MB in size (not only text, also pics), and you can save it to the HD, and perhaps even archive it for future viewing.

[ben2go]

On Firefox, there's an add-on called 'ScrapBook', which you can install, and use to download this whole thread. The whole thread is about 80MB in size (not only text, also pics), and you can save it to the HD, and perhaps even archive it for future viewing.

I got that.Does it download the photos from the thread or the links?

[axa]

I agree, But because I am 6'3 255lbs, guess what ? The bike has more rolling resistance because I'm smashing down on the tires more than a 100 lbs. rider. And I'm catching a heck of a lot more wind than a normal size 130 lbs. person. Therefor wind risistance comes into play also weather you are tall and/or fat. Again I agree with you. I wouldn't belong to a forum that you really have to watch what you say to not get kicked out. I think a lot less of Cleveland Cycle works now for having heard that. The Hiest must not be that great if Clevland Cycle Works has to stiffle the truth.

ive seen this "performance" head from ccw, perhaps it was the 550$ price tag that i didnt look any further...

my initial investigation lead me to believe that it would be difficult to obtain much of a gain by head work on such a small engine. But anything is possible with enough effort i suppose...
But in fact that they consider their "performance" carb is just a 45 pilot, 105 main jet upgrade... for 155$, that was enough evidence for me to judge they are not likely putting enough effort in redirecting the ports to make any significant gain.

Also that dyno chart they provide as 'proof', is IMPOSSIBLE to read... i tried zooming, enhancing... no dice...

Its all smoke and mirrors with them. I get it, they are looking at a different customer, were the right presentation sells the product. similar to the strategy as apple takes.

Anyway, I determined my skills and my lathe will not be able to do the work with the precision that is required, so ive been speaking to a local machine shop about a new bore and sleeve for the cylinder... they have dedicated boring equipment.

Initial indication is that they can do a new bore and new sleeve for a few hundred $, and i live in a very very expensive local for this. New rods, and perhaps a polish may be worth it while the engine is apart...

I am investigating this for a winter project so anyone around the NY tristate area get in contact with me, we will be able to take advantage of multiple piece pricing...

[ProDigit]

I got that.Does it download the photos from the thread or the links?

You can set it to do both... Set it to limit the download to the website "http://www.mychinamoto.com/forums/showthread.php?2738-Dong-Fang-DF-250-RTB-Bobber-Information" and set it to download 3 sub links, and you'll have the complete thread in a ~80MB file. It downloads the photo attachments, but I don't know about the sub-links.

If you set it to download everything, this thread with all it's sub-links are downloaded, but the size can easily amount in the hundreds of megabytes, if not gigabytes.

[ben2go]

You can set it to do both... Set it to limit the download to the website "http://www.mychinamoto.com/forums/showthread.php?2738-Dong-Fang-DF-250-RTB-Bobber-Information" and set it to download 3 sub links, and you'll have the complete thread in a ~80MB file. It downloads the photo attachments, but I don't know about the sub-links.

If you set it to download everything, this thread with all it's sub-links are downloaded, but the size can easily amount in the hundreds of megabytes, if not gigabytes.

Thanks.I haven't played around with it yet.

[ben2go]

You can set it to do both... Set it to limit the download to the website "http://www.mychinamoto.com/forums/showthread.php?2738-Dong-Fang-DF-250-RTB-Bobber-Information" and set it to download 3 sub links, and you'll have the complete thread in a ~80MB file. It downloads the photo attachments, but I don't know about the sub-links.

If you set it to download everything, this thread with all it's sub-links are downloaded, but the size can easily amount in the hundreds of megabytes, if not gigabytes.

You must be using scrapbookplus.Scrapbook don't have those settings.Scrapbookplus isn't compatible with my version of FF.