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Just to recap... I completely disassembled the engine and replaced bearings and gaskets. Along with a new piston, rings, wrist pin. Inspected everything and cleaned her up! Then installed a new HRC hydraulic clutch slave cylinder and mounting bracket. EDIT: I forgot to include using a new OEM cylinder and OEM right center case.
Unfortunately as I have said before, I won't be able to share any internal pictures of the engine. What I can do is tell you what parts are "works" and give a general description.
Actually... it might just be easier to tell you what is stock/OEM 😂
- Right side center case
- Cylinder
- Valve cover
- Shift forks
- Camshaft rocker arms
Every other component is HRC works or HRC spec aftermarket part. All the bolts and nuts Internally are titanium. Externally, the bolts are a mixture of titanium and aluminum.
The Ignition cover, cam chain tensioner, outer clutch case, water pump cover, and left center case are magnesium. Actually I'm not 100% sure the left center case is magnesium. The case has coatings on the outside and internally like a magnesium part but also has exposed bare metal. Which would be unusual for a magnesium part. So... I don't know for sure?
The engine also has an external oil cooler. The radiator portion is aluminum while the tubing is titanium. The cooler will mount on brackets located on the left radiator (will need to get those fabricated and welded).
More about the inside next...
Back to the engine Internal details. I'll just give a broad overview from top down:
- HRC cylinder head: Complete works part. CNC machined ports and combustion chamber. Titanium valves. HRC complete valve train.
- Piston: JE piston with DLC wrist pin
- HRC Pankl rod
- HRC/OE crank: Looks like a heavily modified production crank with metal (the metal is not magnetic) balancing inserts.
- HRC flywheel (heavier than stock)
- HRC modified stator
- HRC transmission and balance shaft: complete HRC with all gear ratios different than stock trans. Basically every gear in the bottom end is HRC besides the kickstart shaft gear.
- HRC billet/Kashima coated aluminum shift drum with insert for gear position sensor.
- HRC/Rekluse clutch: The hub is a works Rekluse part. Totally unique design for HRC. Pressure plate and drive/friction plates are Rekluse.
- HRC hydraulic clutch with a lifter rod unique for the hydraulic unit.
That's pretty much covers all the major components.
I test fitted the 44mm KTM throttle body to the HRC manifold and it fits perfectly.
That was the easy part... Now the hard part. The inlet diameter of the 44mm KTM throttle body is smaller than the 46mm Honda throttle body. Obviously.
Also, the total length of the whole setup, intake manifold back to the intake side of the throttle body is shorter than the stock setup. This is not due to the KTM throttle body being shorter. The works manifold is shorter.
Why? From what I understand, placing the fuel injector closer to the intake valves can increase the bottom to mid power characteristic. This, I assume, would compliment the smaller throttle body (same deal, smaller size low to mid, bigger mid to high).
So I had to make a "sleeve" to compensate for the smaller inlet diameter and the shorter length of the system. This had to be done to be able to mount the stock Honda airboot.
First step was to smooth down the little "lip" on the end of the throttle body. Need a constant diameter to slide the sleeve over.
Next, make the sleeve. I 3D printed a sleeve made from carbon fiber infused PETG (CarbonX by 3DEXTECH). This is a perfect material for this application. Well, I guess metal would be the best but I can't do that.
Took a couple of prints to get the sleeve dimensionally correct (I'm a firm believer in measure once and f@#k up over and over again until its right). But in the end, it look like this part will do the job!
Now all this is just test fit work. Until I get the engine in the frame I won't know if this is the right size (length).
The frame is at Premier Vapor Blasting of Georgia getting... vapor blasted.
Then I guess the next step is figuring out how best to "seal/attach" the carbon/plastic sleeve to the metal throttle body. I'm thinking some sort of epoxy?
Chime in if you have a suggestion!
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I'll look into that... It's a simple easily made piece. Once I have the dimensions locked in I might just get a metal one made. Thank you!
These forks are truly one of the last generation of actual "works" suspension. These forks were made and designed during the pinnacle of MX/SX budgets; 2004-2009ish... Shortly thereafter "works" forks became more production based in design and material. I guess a way of saying it.. "works" forks became more of "fancy" A-Kit forks.
Just one example of the "works" aspect.. One piece machined Kashima coated cartridge. OEM forks and A-kit forks (to this day) use a two piece design
I'll dive deeper into the make up of these forks later... In the meantime check out Tokyo_Tiddler awesome RC250 build. He has a break down of his fork which are one generation older than mine.
Here’s my Geico Honda A kits for reference. These were customized for Hampshire/used for nationals. “Close as I could get to works”.
Would love to see the full workings when you get a chance
I then installed the HRC engine (yes, some bolts/nuts are not tight).
Is this an ouchie on the top of the shock?
Here is a picture as it sits now... Will go into detail soon about what was all done...
As I rebuild the bike, its given me the chance to once again appreciate how special these HRC/Works parts really are...
The HRC rear hub is just INCREDIBLE. The machine work... The anodizing... amazing! In the right light the hub looks like liquid metal
Pit Row
So to make the KTM throttle body usable on the CRF I had to do two main things: 1. Move the rectifier/regulator/condenser 2. Modify the wire harness (connectors and routing)
The stock CRF throttle body has the Rec/Reg/Cond mounted to the bottom of the throttle body. This is not possible with the KTM throttle body because that's where the injector is located. So it has to be moved (just like HRC had to do...)
Stock position of rec/reg/cond.
I had two options when it came to finding a new location/mounting solution. The MXGP HRC or the AMA Team Honda HRC way.
MXGP HRC (new bracket made and attached to the ECU bracket) Tim Gajser bike.
or
AMA Team Honda (modified OE bracket and mounted to engine case)
I choose the AMA Team Honda option. Simply for ease of fabrication. No need to make a new bracket and all I had to do was cut part of the stock part. The mounting location on the case was originally meant for the valve breather tube. I rerouted that and freed up the bolt hole (just like Team Honda).
Step 2, modify the wire harness. The KTM throttle body requires two different connections from the CRF wire harness. One for the Fuel Injector and one for the Pressure Sensor.
I found the required connectors online and cut off the old and solder the new ones on.
New Connectors
Solder new connectors on the harness
Routing the wire harness and new connectors took a lot of practice and trial and error. I wanted it to look clean and professional. In the end, I believe it worked out great and happy with the results!
HRC Map Switch
I also awhile back got the latest HRC steering damper to replace the first generation HRC one I had before. This damper has multiple adjustment capability. I honestly don't know what the adjusters do besides the red dial. 🤷♂️
HRC Steering Damper
Post a reply to: 2016 HRC Team Honda CRF450RW