check these MPS 500's out..

[westsiderippa]

and they are for sale, hmmm, im thinking right now, hahaha

http://portland.craigslist.org/clc/mcy/2078292622.html

here is a question though, will these guys convert a roller chassis for you if you send them your frame?

[cmiller493]

Those look amazing. Not sure about the chassis, Im sure they would for the right price.

[factoryX]

 

[JohnN]

and they are for sale, hmmm, im thinking right now, hahaha

http://portland.craigslist.org/clc/mcy/2078292622.html

here is a question though, will these guys convert a roller chassis for you if you send them your frame?

Check this link....
http://twostrokemotocross.com/2008/12/aluminum-frame-conversions/

[Coop]

Good looking bikes, I am just not a big bore fan. I like "hybrid" builds though.  Seeing all the KX125's with a KDX engines in them over on kdxriders has me cruising c'list for a 125 roller LOL  .

[miedosoracing]

Those people got powder coating happy.  
Although nice, some parts look better anodized.  
MPS does mod frames out for you I believe, atleast they use to. I believe they charge $1400 or so. They have a pretty good name in the industry.
I'm still partial and like mine best. LOL  

[dogger315]

I'm still partial and like mine best

As you should be, she's a beaut!

MY 500 AF is coming along slowly.  Waiting for the cylinder and head to come
back from Forward Motion so I can wrap up the engine build.  I have been
squirreling away parts for months.  The folks at one of the big Honda dealers
have been parting out unsold 2008 CRF250s right out of the crate. 

Here are some pictures of the finished bottom end and the frame I'm using.

dogger

[2smoker]

I'm still partial and like mine best

As you should be, she's a beaut!

MY 500 AF is coming along slowly.  Waiting for the cylinder and head to come
back from Forward Motion so I can wrap up the engine build.  I have been
squirreling away parts for months.  The folks at one of the big Honda dealers
have been parting out unsold 2008 CRF250s right out of the crate. 

Here are some pictures of the finished bottom end and the frame I'm using.

dogger

Just bad ass!

[snowboarderro]

2smoker what  did you use toclean the engine and frame?

[miedosoracing]

I'll just say.  SWEET!!!!

[opfermanmotors]

hmm, a 1983 Maico 490AF...

[SachsGS]

It's interesting to note that MPS uses the 450f chassis's for their conversions, it must be frustrating for Honda to have all of these CR500AFs motoing around.

[miedosoracing]

The other part of that interesting note, is that Service Honda uses the 250F frame, and uses a stock 250F rear wheel.  Now the frame things all good, but come on, a  500 with a smaller wheel? Weight savings is my guess, atleast for the magazines to print...  Some day I'd like to ride another co's bike, because I just don't see how using a 4 stroke frame on a 2 stroke, matches.  My guess is they still turn like a 4 stroke, because the geometry is set up for them, and to track outsides etc. Obviously the 250f handles good compared to the 450F. Mine cuts just like my CR250 did.  I'm not making them anymore and really have no interest in any sales in the MX field anymore, so I can speak more freely now.  I love my 500 and until I ride one that handles better (not sure how)  I'll stick to my 2 stroke frame conversion. The main interesting thing, is that they are finding so many 4 stroke frames to use. I figured out both just part out bikes. I originally thought Service Honda got frames directly from Honda with no VIN, but was corrected on that, and it is just a parted bike.  I'm guessing they love when the 4 strokes don't sell, so they can get a brand new bike for like $4500 and then sell all the parts off of them.
 I did break down and buy a 4 stroke Friday.    CRF50 for my daughter.  

[dogger315]

because I just don't see how using a 4 stroke frame on a 2 stroke, matches

The CR250 frame you used for your conversion is essentially the same gen 3 frame used on
the CRF450 until the gen 4 was introduced in 2005.  Honda didn't build two stroke or four
stroke specific frames.  The geometry was the same for both, here are the numbers:
2005 CR250  - rake 26.5 trail 109.8 wheelbase 58.3
2004 CRF450 - rake 26.7 trail 109.5 wheelbase 58.5 (with 22mm offset triple clamps)
The steering head angle is identical, and the rake, trail and wheelbase figures are within
.3mm of being identical.  One thing I did find that is specific to each, is the suspension. 
When I contacted Pro Circuit about converting my forks and shock from a CRF450 to the
CR500AF.  I was told that in addition to the clevis change for the shock, both components
would need to be revalved and sprung for the different (more abrupt) power delivery and
absense of compression braking.

Service Honda uses the 250F frame

AJ opted to use the CRF250 frame vs. the 450F because of it's lighter weight and better
handling characteristics.  As far as the 250f's smaller wheel and tire, I agree, the bike
shouldn't even be offered that way.  I am still deciding wether to go with a 2.15 or 2.5
rear rim (I may end up lacing both as track conditions demand).

it must be frustrating for Honda to have all of these CR500AFs motoing around.

Unfortunately, with a company as big as Honda, I don't think all those 500AFs even get
noticed.

dogger
 

[miedosoracing]

Although they look to be close, if you look again, those are not matching numbers, they were no where close to being the same while on the bike. The 450 was much fatter to make the motor fit. That of course doesn't change handling, but you know what I mean.  The 450 just was a tank to drive around, and it would not cut. I rode a 2010 CRF450 and it handles pretty good, but again setup for 4 strokes. As far as suspension, the shocks on 2 strokes and 4 strokes are not the same.  I made that mistake and bought a CRF250 shock and it was I think Kayaba or showa and the CR250 was the opposite. It was so close, but no cigar.  I actually have heavier springs front and back than the CR250, but lighter than the 450.  I use about the same as a 250F spring setup.  My bike is very smooth. So 450F suspension setup on it would be way to harsh for me.  Honda notices, trust me.  They did NOT want Service Honda's bikes with the name CR on them anymore.  They also did NOT want their bikes racing against them in races.  If you go read what AJ had said, he had high hopes for their bikes to race and even had some riders to run in the series.  No can do, said Honda.

Dogger, by the way, what is that big thing sticking out on the bottom where the shift lever will be?  Never seen that before.  I will say those cases are very cool looking.  Just curious what that is though.