Fastonthetrack's CR500AF - 04 CRF250R

[Sandblaster]

The following is all from Fastonthetrack

Ok so heres my build. Shes almost finished up now. I've been working on her for a few weeks on the weekends only, whilst waiting on parts to come during the week.

I started with an 04 CRF250R chassis less the engine and a few small items. Unknown to me at the time that the subframe was actually an 06 (dual exhaust and different air box) making the air box conversion a little tricky. I made what i had work when it came to that.

I did all of the work in house (using the CP500 kit) and didnt have to out source anything except engine machining. Heres the beginning portion of the process.

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 101.jpg (125.52 KiB) Viewed 10608 times

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 102.jpg (157.17 KiB) Viewed 10608 times

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 103.jpg (156.9 KiB) Viewed 10608 times

[Sandblaster]

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 104.jpg (74.56 KiB) Viewed 10607 times

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 105.jpg (117.35 KiB) Viewed 10607 times

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 106.jpg (176.52 KiB) Viewed 10607 times

SO, I had the 04 mod plate instead of the 06.. I put it together like this and then just shaved away the excess material.

[Sandblaster]

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 107.jpg (108.67 KiB) Viewed 10607 times

I mounted the Coil here (fully welded later on. Both sides of course)

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 108.jpg (120.22 KiB) Viewed 10607 times

Exhaust mounts look factory IMO

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 109.jpg (66.15 KiB) Viewed 10607 times

[Sandblaster]

Got some cheap China hoses, factory CR500 kit worked great.

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 110.jpg (136.99 KiB) Viewed 10607 times

I got the engine bored and honed out to 89.5mm (one step over stock .020) using wiseco poston kit. Got the bike altogether and running. Was having starting issues due to lack of fuel most likely. Started 5-6th kick. I did two heat cycles then went for a cruise around the block. She rips. Let cool once more and went to start, CATASTROPHIC FAILURE!!! got a nasty kick back, low and behold

Split the right main and case cover..

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 111.jpg (128.48 KiB) Viewed 10607 times

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 112.jpg (225.71 KiB) Viewed 10607 times

[Sandblaster]

I was able to repair the main case with some tricky welding and filing, bought a new right case cover and gasket kit.. Had the engine back together in less than 2 hours.

After that dilemma i was worried about the same thing happening again so i sent my head out to Adam Millar at MillAr Race Engines to have a decompression head mod and a new squish angle machined.

So the engine is now assembled minus the head (i should get it any day now)

I also bought a few goodies while waiting. A little billet never hurt anyone. I also have coil and clutch covers coming to complete the engine.

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 113.jpg (114.03 KiB) Viewed 10607 times

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 114.jpg (73.39 KiB) Viewed 10607 times

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 115.jpg (174.88 KiB) Viewed 10607 times

[Sandblaster]

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 116.jpg (127.71 KiB) Viewed 10607 times

I also bought a 2.9 Gallon Acerbis tank i had to heat up and mold to clear the spark plug and coolant lines.

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 117.jpg (164.97 KiB) Viewed 10607 times

All in all heres a list off the top of my head of the things i purchased for the build

CP500 conversion kit
CP500 conversion tank ( i wont use )
Wiseco top end kit
Full gasket and seal kit
Right side case cover
Boyesen clutch cover
Boyesen ignition cover
OEM CR500 Clutch cable
misc carb parts for rebuilt
IMS shifter
Hammerhead brake pedal
Shark fin billet rear rotor guard
Acerbis 2.9 gallon tank
Honda CRF full hardware kit
Water pump rebuilt kit
CR500 Hose kit Red
Machine work for new top end
MRE Head (decompression and squish angle mod)
OEM CR500 Kick starter (old one was CRUSTY)
1999 CR250 air box and filter assembly
Pro Circuit platinum and T304 silencer
New set of Stock CRF250 wheels (dune tires)
Acerbis Fender bag

The typical oils, lubes and fluids
And of course some Sunoco race fuel!!!!

[Sandblaster]

Mechanically everything works as if it should. I got the cases back in order and inspected everything. nothing was out of the ordinary minus the kick starter stopper was a little cracked, which i replaced.

Heres what the bike looked like last night once i got her able to run again with the new head and decomp...

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 118.jpg (269.76 KiB) Viewed 10607 times

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 119.jpg (183.98 KiB) Viewed 10607 times

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 120.jpg (143.38 KiB) Viewed 10607 times

[foxx4Beaver]

Got some cheap China hoses, factory CR500 kit worked great.

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 110.jpg

I got the engine bored and honed out to 89.5mm (one step over stock .020) using wiseco poston kit. Got the bike altogether and running. Was having starting issues due to lack of fuel most likely. Started 5-6th kick. I did two heat cycles then went for a cruise around the block. She rips. Let cool once more and went to start, CATASTROPHIC FAILURE!!! got a nasty kick back, low and behold

Split the right main and case cover..

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 111.jpg

oem-cycle.com Fastonthetracks CR500AF - 04 CRF250R 112.jpg

that is one ugly failure!...I myself have never seen a kick-back destroy the cases before...until now
nice build though!...I don't generally follow Honda builds, but I like what you've done.

[Sandblaster]

Yeah, that is the CR500's biggest drawback...
We are getting ready to build a CR500 engine.
Roost is doing the top end and we are doing the bottom, then install the top.
The customer will install it in his bike, then we will help with break in.

[fastonthetrack]

I figured I would join this site as well. Thanks SandBlaster for posting my build. Any questions i can answer no problem!

I got the bike finished and riding now. RIPS, picked up another CR500 engine as well for a different build.. 85 model.