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

Today, I received this exact copy of the HRC skid plate from Giuseppe B. in Italy who is a true master craftsman. He made the mounting brackets and supplied titanium bolts and everything fits perfectly. The skid plate even has the notches on the right side to provide clearance for the frame inserts and welds for the HRC water pump guard. I will have to remove the engine to weld in the mounting brackets.





Here is an original HRC skid plate so you can see it was replicated perfectly.



HRC had 2 styles of skid plates, the style used by the US team above and the style below used by The Honda Japan and MXGP teams which wraps around the outside of the lower frame rails. I think the US design is a much cleaner design. Here is a pic of the Japan guard where you can see how it wraps around the lower rails. Occasionally I saw the Japan team use the US style skid plate, but mostly they used the other style.

Yes, It is one of Frederic Bolley's 2000 bikes.

The bike is finished essentially.. found all the parts I needed and just waiting on a titanium kickstart knuckle as the last part for a complete Japan RC250M factory machine from the 1999-2000 All Japan Motocross Championship series. This bike won the championship both years as well the MXGP championship in both years when HRC machines were still king. It probably would have won the AMA championships also if it weren't for Ricky Carmichael on the Kawasaki.




HRC front caliper is actually a 1991 unit fitted with titanium brake pistons and other HRC titanium hardware...



Pretty much every nut and bolt is correct except for a few areas where a decided to upgrade on the Japan team's machine and used HRC titanium instead of oem steel used by the factory team (ie linkage bolts) or used 2001 and 2002 HRC parts where the Japan factory team used oem (ie. front axle dust shield, rear axle blocks).



There is nothing like an HRC pipe which connects to the aluminum stinger on the kevlar silencer. Since aluminum would wear quickly on the steel, HRC welded a titanium connector on the end of the aluminum pipe...



The kevlar silencer is NOS and I can't bare to start the engine with it on (for now)...



HRC titanium axle contrasts with the aluminum axle block and axle nut reminding one of the careful selection of metals for each part by HRC. HRC chain guide and special rear sprocket made by Renthal for HRC are some of the special parts in this picture. HRC used OEM axle blocks until 1999 or so. In late 2000 and 2001, they used this special design...


There is nothing as tidy as an HRC engine. I am one that feels that this was the best 250cc 2 stroke Honda engine of all time.

The builders of these 3 RC250M recreations often consulted with each other during our builds. They are arranged in chronological order.. the first is my bike which the factory team raced in Japan in 1999 and 2000. They had 3 riders on this model bike until one of them (Odagiri) dropped out of the nationals to focus on development of the all new CRF450.

The 2nd bike is the the bike built for Ricky Carmichael to race the 2001 MX des Nations when he first transferred from the Kawasaki to Honda factory teams. Unfortunately he would never race this bike due to September 11th with the US team not participating that year because of the terrorist attack. It is said that this bike was recreated from one of Tortelli's bikes for the photo shoot. The bike includes many of the HRC parts used by the MXGP and Japan factory teams such as the aluminum fuel tank and the long Kevlar silencer. I do have a few pics of Carmichael riding this bike, though. It would have been legendary to see him ride this model at the MXGP knowing what he was capable of on the 2002 RC250M's such as passing Everts on a big 4 stroke for the win.

The third bike is the machine that Yoshitaka Atsuta raced one more year in Japan. However, his other 2 factory teammates were on completely different machines. Kazu Odagari was racing the CR450 pre-production machine and Ryuichiro Takahama was racing the 2002 pre-production CR250. Honda was benchmarking the 3 different machines side by side for development. Notice the prototype 2002 shroud graphics on Atsuta's machine.



Here we have the 3 recreated RC250Ms alongside the original factory machines that inspired them. Aside the from these recreations, the only way to see one of this works bike is when Honda decides to display one of the couple of championship bike it has kept at their museum in Motegi, Japan. Currently none are on display and sit under a plastic cover in the Honda museum warehouse.

Not sure why the HRC magnesium ignition cover turns grayish green whenever we get long periods of rain while the HRC magnesium clutch cover is not affected and the Honda racing logo stays nice and shiny. The ignition needs to have the logo cleaned up with sand paper a few times a year. Maybe the magnesium alloy is different but the ignition cover is untreated and the clutch cover has a gold coating underneath followed by the dark gray Dow coating. You can get a glimpse of the gold coating near the bolt holes.



HRC tried 4 or 5 versions of the rear brake caliper guard and a few versions of the rear disk guard before settling on the final version used on the 2001 RC250Ms and continuous on all OEM Honda’s right up until about 2018.

Here is a beautiful NOS Honda billet crankshaft, but surprisingly it is not HRC. It is the special run of billet cranks that Honda made for the first roughly 500 1973 CR250Ms off the production line when the production cast cranks were not ready in time for the highly anticipated introduction of this game changing race bike. It must have been very expensive for Honda to put these cranks in the first CR250M engine to avoid missing their planned launch date.



As this RC250M build is coming to an end, I have started a new bike build thread over in the bike build section. I am hoping to create a show room quality 1973 CR250M. The bike that really started it all in terms of track ready production motocrossers that can be raced right off the showroom floor.

https://www.vitalmx.com/forums/Bike-Builds,46/Showroom-quality-1973-CR2…

There is one last HRC part that I never found.. a correct HRC titanium kickstart knuckle for this build. If anyone has any leads on the whereabouts of one, please PM me...

So happy to see my bike selected as bike of the day..

https://www.vitalmx.com/community/Tokyo-Tiddler,16129/setup,92608

Richard, JMX82, Ritchy, Zookrider.. many thanks for the comments.. always appreciated.

Richard; it will certainly get started and ridden down the street, but I think after she had been sitting collecting dust for a while, I will have to put on some old plastic and take her into the dirt to hit a few jumps. As long as it is a dry track and no mud .

Many thanks for the compliment!

There is no reason for me to want to do a titanium subframe on this build. Firstly, the factory team/ HRC did not use titanium subframes on these RC's, they used aluminum. Secondly, the aluminum is noticeably lighter than the titanium and is strong enough for the job it needs to do. I would not want to make the bike heavier and less correct, especially for a part that will not be seen (I admit that titanium can be pretty, though!).

mike

That particular front wheel spacer is from Ian Hamilton at IRP.. http://www.irp-llc.com/products/products.html

He makes nice stuff. I believe he makes some of the parts for MotoStuff.

Warning.. I had a lot of free time, today, so this is a long diatribe on HRC kickstart knuckles.  I had been searching for an HRC titanium kickstart knuckle for years w/o success. As there are many different knuckles that have the splines clocked differently to fit the different frames and pipes, finding the right one is not easy, especially for the 2 strokes.   From what I have noticed, HRC made the titanium kickstart knuckles from 1997 until 2016. From 2017, there are no more kickstart levers due to the electric start so these knuckles have gone the way of the rotary telephone. Nevertheless, there are at least 7 different HRC knuckles, 1997-99 2-stroke, 2000-01 2-stroke, 2002-2004 2-stroke, 2005-2007 2-stroke, 2002-2004 4-stroke, 2005-2008 4-stroke, and 2009-2016 4-stroke. Honda redesigned the knuckle each time there was a frame and/or exhaust pipe change.

While I was looking for the HRC Ti knuckle, I looked into a way to make the OEM steel knuckle look like a Ti knuckle and it was much easier than I thought.  As you can see from the photo attached, the OEM cast steel knuckle looks like total crap. I had thought the oem knuckle was zinc coated ordinary steel, but after working with it, I believe it may be stainless steel considering the softness of it and how well it polished up. I took a small drum sanding bit on the end of a Dremel tool and smoothed out the casting lines and squared off all the sharp edges so it looked like it was CNC machined. The trick to making cast steel or aluminum look like CNC titanium or CNC aluminum is to polish it up to a mirror finished and then knock off the shine with WD40 and a 3M pad. Always looks nice. I made 2 of them and they came out better than expected. I also drilled the hole for the safety wire. The 2nd pic shows the final product.

It would be hard to tell it is not an HRC cnc titanium knuckle unless you put a magnet on it. Even side by side, the steel knuckle looks close to the HRC Ti knuckle, I just picked up. Here they are side by side below..

Here are some pictures of each of the Ti knuckles that HRC made.  One of the biggest distinguishing features is the shape of the boss facing out that functioned as a stop when the kickstart lever faced out.

This one was used on the 1997-1999 RC250Ms as well as the 2000-2001 US Honda team’s factory bikes and Ryan Hughes’ PAMO MXGP bike.  This is the HRC knuckle I currently have. Notice how the top of the knuckle that the lever swivels on, it is machined out unlike the solid OEM knuckle. The HRC titanium knuckle weighs 48 grams while the OEM steel knuckle weights 96 grams.  While titanium weighs ~58% of that of steel, the extra machining on the HRC knuckle makes it even lighter than the oem part;

 

Here is the knuckle and style lever used by the Japan factory team and Frédéric Bolley on their 2000-2001 RC250Ms;

The knuckle for the 2005-2007 2-strokes used a knuckle that was shaped like the 1997-99 knuckle, but with the different lever style like the 2000-01 bikes;

 

Here is the knuckle for the early 2002-2004 4-stroke factory bikes, it is distinguished most by the very square boss

The last knuckle that HRC made fits 2009-2016 4-strokes and is distinguished by the beveled loop that wraps around the splined kickstarter shaft. That part of the knuckle on earlier versions are machined very square.

 

 

******* I am still looking for the 2000-2001 HRC kickstart knuckle and have the 1997-99 HRC knuckle to trade. *********

 

Thanks Guys.. I know it is pretty nerdy, but you really have to spend a lot of time pouring over these details to recreate an accurate works build. I am also interested in how the technology of the MX bikes have evolved since the early 70's.  The mid-70's works RC's had titanium bolts, but in those days, titanium was thought of as the kind on material you would only find on NASA spaceships , but today it is a fair common material for easily obtainable aftermarket parts.  I was really interested in when Honda started using machined titanium parts on their works bikes, but any photos before the early 2000's are going to be so grainy that it is hard to discern smaller parts. I did just find a couple of good photo's of Jermey McGrath's 1996 works bike and I can see that the kickstart knuckle is stock OEM steel as you can see the casting line on the knuckle similar to the oem knuckle I just posted.  Also, you can see the rust on the left side steel foot peg, so they were not made of titanium either. Therefore, it seems it wasn't until the first generation aluminum framed works bikes that HRC was machining parts out of titanium (other than the bolts, of course).