BannedCR500Riders.com

So for those of you who don't know the story... A friend who is on the board as "fatcobra" bought 2 gen-4 bikes. he and I made a deal, I get 1 of the rollers for doing his conversion. Works well for both of us, he gets a free conversion and I just do everything x2. I got the first chassis from him yesterday, this is the one that will be my bike.
so I started with cutting off the front mounts, then I cout out the Y. I cut as close to the welds as possibe and kept the lower tubes at an angle so it will be stronger and allow me to make the peices a tighter fit.

Those gen 4s are so easy it's ridiculous.
Next time though I will just cut the whole cradle off and get a fabrication shop to bend the tubing, I don't think it is any more effort and the result much nicer.

what bike is the gen 4 frame? is the gen 4 not the first model crf frames? looks like you'll be done asaaaaaap....

its an '04 crf250r first year gen-4

what gen is a 05 450x ?

4
the gen 4 is '04-'08 crf250 x and r
and '05-'08 crf450 x and r

Where do you get the alum tubing for the cradle? What kind is it?

I got the last of what Bob used.

There is a couple of places online with the radiused tubing. Has anyone tried to get some?
I thought that would make a nice kit for gen 4, pre-bent cradle pieces and a hoop for the motor mount.

that would be pretty badass, but that bend is pretty complex, it seems to twist a little and isn't a perfect radius. From what I understand, the big guys (TT, SH) who replace the whole cradle, just use a bender.

Kick ass. Take lots of pics of this build.

I'm gonna, I'm going to try to take pics of every single step to give people a true step by step gen-4. Plus I'm going to be starting the 2nd bike soon too, so I can even get pics from both bikes. This thread should end up being VERY detailed!

Lookin' good Danny!

that's how you do it Baller!

Alright guys, I had another half an hour today while the wife and kids were out.
I only got the lower mounts removed, but this is probably one of the tougher parts...
first I busted out my dremel with 1 1/2" quick release metal cut off wheels and cut around the insideof the welds careful not to go too deep. once I was close, I shoved a big screw driver through the hole and lifted until the small foil of metal left holding it broke. Took about 15 minutes and worked out great.
Then I grabbed my 4 1/2" angle grinder with #40 flap disc to grind down the welds. if you use a standard grinder it will load up and not remove anything.
next is the notch for the clutch cover bolt. after that I an going to be removing the original frame peices from the Y.

CR500R-G3 wrote:Lookin' good Danny!

ShanMan wrote:that's how you do it Baller!

thanks guys!

Does this build require the Y to be raised?

Looking real good by the way Dano!!

Alright guys, more progress:
I cut into the frame for clutch cover clearance. I am going to put peice in it and weld it, so I made a little extra room.
cut the peices out of the Y. on the front and back there are extra welds that dip down a little mors. I cut triangles to get it apart and plan to radius them come welding time.
I cut about 2" off the middle spar, I think I may need to cut some more. That spar gets thicker as you go up, so some trimming will need to be done.

nice work danny. whats the difference in gen3 cr250 and gen4 250f ?

the 06 450f I worked on was perfectly square, just a plain bend.

I'm in NYC, and could feel the hairs on the back of my neck stand up....



Danny, when I spoke to you about rotating the motor more, I suggested cutting the cradle to allow two split pieces of aluminum tubing to be welded in.... If you need help locating it, let me know.

Otherwise, lookin' pretty good!

I'm glad you started it, sometimes thats the hardest part!

100hp honda wrote:nice work danny. whats the difference in gen3 cr250 and gen4 250f ?

not much performance wise, but a lot conversion wise, the frame is easier and the rads are easier on the gen4, but the rest of the chassis is a PITA on the gen-4, the airboot is useless and I'm definitly not looking forward to the gas tank! but both make a kickass bike in the end!

AlisoBob wrote:I'm in NYC, and could feel the hairs on the back of my neck stand up....



Danny, when I spoke to you about rotating the motor more, I suggested cutting the cradle to allow two split pieces of aluminum tubing to be welded in.... If you need help locating it, let me know.

Otherwise, lookin' pretty good!

I'm glad you started it, sometimes thats the hardest part!

I was planning on sticking that solid stuff you gave me inside and welding all the way around, that should allow enough room and keep it strong without adding too much weight. The solid peice will only be about 3/4" long.
Thanks Bob! Ya, I'm getting started hard core, I'm working on it every spare moment and its getting closer in front of my eyes! I plan to have all the frame stuff tacked and ready for the welder by the end of the weekend

Danny, is it always necessary to cut that notch for the clutch cover bolt on all conversions? i was told somewhere sometime that as long as the flat bottom of the clutch case is somewhat parralel with the frame it's good to go, I have the bolt sitting just about a millimeter from the frame and the bottom of the case is flat... i need to know this shit i'm glad you are doing this so detailed...

I'm pretty sure that the gen-4 250 chassis is the only one where it is a big problem, if on yours the motor can sit level without touching, I'd leave it alone.