2001 CR250 $pecial Restoration Part II - Recreation of a 1999-2000 Japan Honda Factory RC250M

Took me 4 years to find a nice kill switch to match the HRC ignition advance button, but Giuseppe Bonamigo just started making these very nice replicas. The replica I had made to stand in temporarily while i found another switch was decent, but not as exact as this one. Only the Japan factory team used the same switch with the 2 piece aluminum housing for both the kill switch and the ignition advance button, while the US and MXGP factory teams used an OEM kill switch together with the HRC ignition advance switch. Now everything in plain view around the handlebars is 100% the same as what the Japan factory pilots had back in 2000.


The HRC rear spokes that came off the 19" wheel that I started with were not what I expected. I expected them to be beefier than OEM, but actually HRC used a spoke that was swedged at both ends along with an aluminum nipple. The spoke was a little bigger than 8 gauge at both ends and a little smaller than 9 gauge in the middle. This means that compared to an OEM CR500 spoke, they were fatter at the 2 ends, but thinner than the OEM spoke in the middle. Hard to see in the pics, but if you look closely, you can see the ends are swedged. They were after weight reduction here and must have replaced these spokes quite often before they stretched.

The way to tell an HRC DID rim from an OEM DID rim, is that the HRC rim will have the part/ size information on the side of the rim while the OEM rim has the part/ size info facing up on the rim. Most major HRC parts will have a manufacturing date on them to keep track of what version/ batch they are from (the factory parts were often constantly having minor tweaks made to them) and how old they are. Here is an HRC rear rim.. the part code usually starts with a "J" followed by the rim size (19xMT2.15) and finally the manufacturing date; "1 97" and "DOT". This HRC rim was made in January 1997.


I finally got the wheel laced up with the right spokes.. many thanks to Buchanan spokes for helping me find the right length.


I certainly have more money into this rear wheel build than I anticipated, but she is looking pretty good..

Rear wheel is finally together and it was a bit of a time consuming hassle as well as a costly addition. All the parts for a complete HRC wheel are special works parts, even the sprocket. The sprocket is specially made by Renthal for HRC to fit the HRC magnesium hub, the brake disc is a special 6-bolt version compared to the 4 bolt OEM disc and uses special titanium m6 rotor bolts with one flat side on the head. The spokes are double swedged with aluminum nipples and a steel grommet on the spoke end that rides on the magnesium hub. The Japan HRC was using a special wide 18" rim to improve contact feel with the ground. The tire size used was a 120/90-18. A standard width 19" rear tire was swapped in for mud races since the narrower tire held less mud.



I re-anodized the rear spacers the green color used by HRC Japan. Again these are HRC specific spacers with each spacer being a different length. The longer one goes on the brake side.



I used this cool new tool called the "Baja No Pinch Tire Tool" that pushes the tire bead over the lip of the rim so you don't have to use tire spoons which scratch up your rims. This is the first time I used 2 rim locks and it greatly increases the difficult of installing the tire. Normally you would start installing the tire from the air valve and end up at the bead lock. That won't work with 2 bead locks. The only easy way we could get it on was start in the middle of the rim lock and air valve and end up on the other side between the rim lock and air valve. Kudos to the boys as RG3 New Jersey for helping my get the tire all the way on. The tire is a D952 which is a retro tread pattern based on the old D752 tire which is correct for this period.




The wheel looks the part now..


To be honest, while HRC hubs are nice and carried a lot of riders to championships in their day, the Martin Honda hubs that I originally had on the bike were much more beautiful and also very rare pieces.



Thanks to my friend William for this period correct NOS special edition Renthal bar pad. It was a non-standard color called "titanium chrome".

Hi Mike; does your late model HRC rear hub also require different sized spacers like the 1997-2001 HRC rear hubs? It is easier to find a rear hub than a front hub because the rears require so many special parts that people just didn't bother. The front hubs will just bolt up to a production CR and thus they are harder to find 20+ years later. It is the one HRC part that surpasses the HRC triple clamps with its special bearings and races in the PIA department. Satisfying when you get it all figured out thought.

I had the complete HRC wheel to start with, but it was 19" and this build called for an 18" special wide rim. It was worth the hassle as looks cool and different from most rear wheels. The riders really liked the wider rear tire for MX and a number of championships were won in Japan and Europe in those years with this set up. The problem became when the other manufacturers did not follow Honda's lead and this limited the number of 18" tire compounds available for MX. It does really change the way the bike feels in terms of contact with the ground.. it feels more "glued" to the track.

Yes, I plan to redo the full bike pics when I get all the new parts on which will be soon. I made enough updates to merit a new photo shoot.

I started with a long list of 55+ HRC parts to build a complete RC250M (excluding engine internals). I have them all now except for the following items;

-HRC skid plate: I hope to have a perfect replica soon and one is in the works with the prototype finished last week. There are 2 styles used by HRC during these years.. the classic design used by the US team while the Japan team used a different design that wrapped around the outside of the frame rails. The design that the US team used is a cleaner design IMHO.

-HRC titanium kickstart knuckle: I am having replica machined from titanium, but unsure of its status or when it will be available

-HRC prototype rear brake set up: This will be the hardest part(s) to find as they were the prototype used in 2000-2001 to develop the system used on all Honda MXers from 2002 until today. Mounting is different than the 2002+ oem unit and the master cylinder and caliper are all sand cast parts. It also requires a revised swingarm and a different HRC brake pedal to make it all work. It would be a heck of a find if I ever found it.

I weighed it earlier in this thread. While the bike has many superlight parts from titanium steering stem, pegs and featherweight Kevlar silencer, it also has parts that are heavier than OEM such as a boat anchor for a shift lever, wider tires/ rims, and bigger forks. In one of the Japanese magazines that test road this model RC250M, they did write that they were surprised when the HRC team director told them that it only weighed a few pounds less than a production CR250R. When I weighed it, that is what I found.. it weighed about 213 pounds. I think mine is probably a little lighter than the original RC250M since I have a few more titanium bolts (HRC Japan used steel on the linkage bolts) and I don't have the many reinforcing gussets and cross braces welded on the fame as the Japan team did. I think it was a mistake on their part as the frame is strong and stiff enough. The MXGP and US Honda factory teams did not reinforce the frame the way the Japan bikes were gusseted all up, Take a look at the steering head of the original Japan RC's I posed and you will see massive gusseting of the steering head.

They also added cross braces for the front down tubes under the exhaust area, the inside of the main spars where there is a cross brace in front of the rear shock and they also added welding on the frame around the foot peg area. I think it was overkill that the other teams did not adopt.

Somebody needs to copy the HRC rear brake pedal.. easy to do and such a hard part to find. The HRC brake pedal for the 2 strokes is a cist piece unlike the CNC machined HRC pedal have on my CRF450. A CNC machined version would be nicer anyway and they could machine the 2 different versions depending on what style rear master cylinder is being used.

Hi Mike, I see your works Showa forks have the new lug style. I had thought that HRC was using an OEM style front axle for the latest set of lugs and front hub? I had heard that for the later bikes, HRC had 2 axle sizes as some riders didn't like the flex of a titanium front axle with the OEM axle diameter size. Do you have a pic of your front axle? Is it a 2-piece titanium and steel axle like the HRC axle I have? Here is mine;

Another pic showing how my HRC axle screws into the titanium piece in the left side lug. This design doesn't pull the left side fork into the hub and allows both the lugs to float on the axle where they want to be and you just tighten both lugs down on the axle in the position they want to be. The OEM front axle only allows the right side lug to "float" before tightening.

I don't have the final file.. I only have the 3D file for an OEM guard which I gave to someone to modify into the HRC replica guard. He has the final file as part of the deal. I noticed that you only have one post since joining Vital.

Thanks Bryan.. I have learned a lot about "works" parts since embarking on this project. Usually we thing of the HRC works parts as the prototypes of parts that will be found on future production Hondas.

The HRC brake caliper housings, master cylinder, and now the front axle axle we find were just resurrections of 10 year old production oem parts. I wouldn't have thought this, but now it is evident. I imagine that Honda ceased this older oem technology because of costs, even though it had notable advantages.

All HRC did was add titanium to the much older technology.

I now look at 1990/91 production CR's in a whole new light.

Here is a pic of an old used 90/91 oem CR front axle..

Got the HRC rear wheel mounted along with the HRC front brake caliper, titanium swingarm pivot, replaced the red silicone radiator hoses with NOS oem hoses, and a few other things.

I learned quite a bit about these RC250Ms during the build. I am sure I am not alone to think that some of the HRC parts foreshadowed what we would see on future production bikes. I was surprised to find that some of the works technology was actually 10 year old production CR technology such as the front caliper housing, the front axle design, the magnesium rear hub, the design of the Nissin works front master cylinder.





I meant to compare the weights of the oem vs HRC front caliper set ups on a scale, but I forgot, but I can tell you that the older caliper with titanium pistons and hardware was far lighter than the oem caliper. It does cause one to ask why Honda made the later caliper housings so much heavier with the reinforced housings if HRC preferred the older housing. The physical size of the older housing is notably smaller.

It took me a long time to decide to swap out the much nicer looking Martin billet hub to the painted HRC magnesium hub. I made sure there was plenty of coolness in the HRC wheel with the wider rim, 6 bolt HRC rear brake rotor, and the HRC/ Renthal rear sprocket which seems to have a different sheen than the standard Renthal sprocket so I wonder if they used a different aluminum allow for the HRC piece. The wider rim gives the mx tire more of a trials tire look as the fresh knobs look smaller with the slightly wider width..


The 40 minutes extra work that it took to give the rear brake caliper hanger a CNC machined look was well worth the effort. It came out great..




While I had the bike apart to install the NOS oem radiator hoses, it gave a chance to admire some of the HRC parts that were hidden such as the HRC titanium air filter bolt, titanium exhaust valve adjuster bolt, the full beauty of the NOS kevlar silencer, etc. The HRC Kevlar silencer has a "cut-out" in the shape of the rear caliper molded on the inside/ bottom to keep from getting crushed by the rear brake caliper when bottoming the suspension hard. While there were several design HRC pipes available to the teams, the one I have was needed to fit the big HRC exhaust valve cover spacer I have on there. This is what the Japan and MXGP teams used. The US team used a very different shaped pipe.





Having found 54 of the 56 parts I had on my HRC parts list to produce a full RC250M, I am running out of things to do to the bike.





One new part on the way is this HRC skid plate. I will have to remove the engine to weld in the mounts.

Thanks Damien. Since it is meant to be a piece of living room eye candy, at this point I have a few more HRC parts and bits of titanium than the Japan team actually used on their 1999-2001 RC250Ms. While they had the titanium parts available, they preferred to use the OEM steel swingarm pivot and linkage bolts. For the front axle dust cover, they used the OEM gray plastic piece while I am using the HRC one piece aluminum spacer/ cover that was used on HRC works machines from 2002.

Hi Rich, the 2 HRC parts are;
1. The prototype sandcast rear brake set up that was introduced to the Japan and MXGP teams in 2000 and the US team in 2001. There are actually a couple of versions of the prototype rear caliper (each with a different caliper guard) that I have seen while it was in development. Because it was a prototype part that only fit the 2000-2001 frame, there aren't that many to be found. It requires a number of HRC parts to retrofit.. sandcast master cylinder, sandcast caliper, different HRC rear brake pedal, HRC modified rear swingarm (or you have to cut-off and relocate the rear caliper mounting bracket slider to a different position on the oem swingarm).

The final version is very similar to the oem rear brake set up used in all Honda MX bikes from 2002-2021. I tried to retrofit a 2007 CR250 rear brake set up, but it is too much work and wouldn't look right if I modified the frame to mount the 2002 master cylinder or tried to reweld the cast aluminum mounting tabs on the master cylinder. My current rear brake set up is correct for a 1999 Japan RC250M, though, so I am not sweating it.

2. HRC titanium kickstart knuckle.. there are many types out there and I found many HRC 4 stroke knuckles, but not the correct one for the 2000-2001 2 strokes which are different from the 1997-99 knuckles and the 2002+ knuckles. A used, worn one wouldn't do either, it had to be an NOS part. However, Stevie Denton, has already started making me a replica. I sent him an NOS OEM knuckle and he is copying it in titanium so that problem will be solved shortly. It is hard to notice on the bike, but unlike the rear brake set up, it is one simple part that I couldn't find and just had to have it.

So it will really be the prototype rear brake set up that I won't have in the end. One may turn up eventually.

Well, it is mostly the HRC titanium bolts.. I don't think the quality of the titanium those days was quite the same as today. My bike is for looking at, while the actual race bikes were for winning championships and for ease of constant tear downs. I read that they often had to hammer the titanium swing arm bolts out as they would bend at race speeds. Same for the linkage bolts where they mostly preferred OM steel over the HRC titanium. I saw the titanium shock springs on the Japan team's practice bikes all the time, but they didn't dare use them for racing those years because of concern for breakage so they developed a special steel alloy spring that was lighter than OEM but no where as light as a titanium shock spring. RCS seems to have the breakage problems all sorted out, nowadays. The mechanics also used steel nuts on the titanium bolts, because of the frequency of galling when using titanium on titanium. It happened to me a few times and even a brand new titanium bolt with assembly lube on it will gall, and it is a b%$@tch to get off. It doesn't make for a happy mechanic. Then there is the HRC front brake line guide I have on the bike that is rare even among the teams who normally used the OEM guide. I have found a few pics of the special guide on some of the Japan team bikes, but an OEM guide was the norm. The factory teams were all about weight, strength, function and adjustability rather than looks.

I actually have a greater appreciation for OEM parts after this build, even if they are not as cool as a works unobtanium part. The one and only factory part that might make us faster is the works fork.. most important part on a bike for going fast IMHO. A very well set up modern production spring fork might be closing the gap though.. to a point.