2015 winter project - Home built "works bike" - Part II

This is part II of my previous thread on building a “home-built” works bike as a winter project. I took it a step further. It doesn’t compare to the beautiful work that Dogger, Newmann, and other craftsman, but it is my attempt at building something unique. These days, you can buy a lot of cool parts that weren’t available many years ago and build what was once only available on works machines. The idea was that I would throw a lot of money at the bike, searching all over the world and testing various parts to separate the “chaff from the wheat” so to speak, but I did end up with a few actual unobtanium works parts in the process. I don’t like the air forks, dual mufflers or pointy plastic of the 2013+ CRF’s so I started with a left over 2012, one of the best looking bikes to come from Honda in the last few decades. I also am a 2 stroke guy, so to make a this 4 stroke more to my liking, I decided it could weigh no more than my CR250, had to have similar performing suspension to the works Showa’s on my old 2 stroke, and I had to get rid of the 4 stroke engine braking as much as possible.

http://www.vitalmx.com/forums/Moto-Related,20/Winter-Project-Home-built…

This 2012 CRF450 now weighs less than the AMA limit. I weighed it yesterday and the wet weight (just over ½ tank of fuel) and it was 225lbs. Dry weight is between 218 and 219lbs.

1. The weight reduction is due to;
-Complete Mettec titanium bolt, nut, and screw set, including both axles and swingarm pivot
-All plastic body parts and engine cases use IRP aluminum bolts
-Carbon fiber parts include; fuel tank, engine mounts, front and rear brake rotor guards, rear caliper guard, chain guide, oil filter guard. Most came from Europe from the teams and manufacturers that make the parts for the GP bikes
-I used the lightest hubs and rims I could find. The hubs are TCR, but the rear is a lightweight version machined for the Geico Honda team. The regular DID Dirtstar rims are stronger than stock but lighter than the LT-X version.
-Titanium rear shock spring
-HRC titanium foot pegs and mounts
-CNC machined front brake caliper, fork lugs and fork caps.
-Think technologies bar pad and seat foam (I am in the process of replacing this with Guts racing seat foam which should be a little more comfy)
-Removing the air filter backfire screen was a nice little weight loss, for free.
-Titanium and carbon fiber exhaust was the most cost effective weight saver


2. Suspension mods with valving and lots of help from Paul Bruno at RG3 New Jersey:
- Both the forks and shock body were sent to Japan for Kashima coating
-Fork tubes and shock shaft were DLC-coated
-SKF fork and shock seals were used along with a low friction piston band in the shock to lower stiction
-The fork got the Kayaba “works” outdoor spring perches, pistons, and FC oil lock collars, along with CNC fork lugs from Italy and CNC fork caps along with FC pressure springs and .48kg fork springs
- The rear suspension is helped by a Merge Racing knuckle. The rear shock also got “works” aluminum preload rings with bearings to prevent spring torsion and an increased volume bladder cap, and a 5.3kg titanium shock spring. A custom preload spacer and reshaping the exhaust were required to make the Ti spring work.
-The steering damper was re-valved by Factory Connection to help with the cornering feel and it helped a lot along with the Merge knuckle

3. Engine Mods:
-I tried 3 different exhaust systems and ended up with a hybrid of 2 different systems that I thought offered the lightest weight and best performance. I use a titanium header from Yoshimura and FMF’s 4.1 RCT titanium and carbon muffler
- Injectioneering throttle body mod. this mod really makes the bike pull lower and smoother off the bottom especially when cracking open the throttle at low rpm
-Air filter back fire screen removed, HRC injector mod, Simon choke mod, Split stream valve cover vent rerouting kit also help a little bit
-Tokyo Mods fuel and ignition mapping (I use VP T4 racing fuel)
- Moto Tassinari Air4orce airboot with the long velocity stack
-Ron Hamp camshaft with decompression spring mod to reduce flame outs
- Tokyo Mods cam chain tensioner
-The clutch was replaced by a Rekluse EXP 3.0 set up to give the least engine breaking. Clutch pull is assisted by a Works Connection Pro perch
-Rear sprocket was changed to 49 teeth to help the engine do its job
- Boyesen Super Cooler water pump and CV4 Y-hoses that eliminate the restrictive fittings, and a higher pressure CV4 radiator cap
- 2015 black valve cover secured with titanium bolts

The above bods make for a bike that is quite strong from bottom to mid and really improved the throttle response which is important to me.

4. Brakes:
- The front got the Moto Stuff 280mm brake rotor used by the Geico Honda team and a Ride Engineering front brake caliper. These 2 parts were made for each other and gives a front brake that is at a whole different level. A Pro Carbon front disc guard from the UK and an Acerbis wheel spacer to mount it
-The rear also has a Moto Stuff lightweight brake rotor mounted with Ti bolts. There are IRP aluminum banjo bolts front and rear along with Race Tech titanium caliper pad and DLC-coated slider pins

5. Miscellaneous Parts/ Ergonomics:
- There are a number of HRC parts on the bike including brake master cylinder covers, brake line brackets, lower engine mounts, and a set of HRC triple clamps that are a bit lighter than stock
-The handlebars were raised 6mm using MXBONZ mounts
-The foot pegs are relocated 5mm up and 5mm back
- 15mm longer Hammerhead billet shift pedal was added to keep my size 10 boots from getting caught under the shifter whenever I upshifted while seat bouncing in the air which was a constant problem

There is a smattering of other parts that I am sure I forgot to mention.

Here is also a picture of a YZ144 I just built for my son. It has a Terry Varner motor and RG3 suspension…

mike