C & J Honda Xr500

C & J HONDA XR500

Ron Griewe

A Raceable Honda Four-Stroke

Hondas's 500cc four-stroke has been wished for by many off-road and trail riders for several years. Everyone knew Honda had the technical knowledge and foresight to build a dynamite 500 class four-stroke the right way. Undoubtedly the engineers at Honda had closely studied the Baja-winning Bill Bell C&J Hondas. and understood what we crazed Americans wanted. How could they continue to ignore us year after year? Finally the grapevine told us the 500 Honda Single would become a reality for the '79 model year.

We tested the new 500 in March and to no one's surprise it proved the best massproduced 500 four-stroke, off-road machine to date, but . . . some of us expected more. That is. a machine that was more race oriented and less pla\ oriented. We purists didn't like the 23-in. front wheel that dictated how the rider would take a corner. We felt the rider should tell the bike. The same hard core group also voiced displeasure with the lack of wheel travel and the quality of suspension. It worked well at moderate speeds but when pushed hard for an hour through whoops, the rear shocks went away and never were the same again. Tireroading wasn't much fun on the XR either: the soft suspension let the bike wallow in high speed situations and preloading the springs caused the fork to top badly. The sea Hank junction was another sore spot. A forward riding position, necessary for many situations, would pinch the rider's leg. The shape of the tank's rear and seat front are wrong and tend to open up and bite the rider w hen aggressive riding is attempted. The brakes are again fine for trail use. but not up to racing standards. The new 500cc engine was one thing none of us could fault. It started easily, ran smoothly, didn't vibrate, pulled stronglv from idle, produced good horsepower and was almost perfect. The new XR500 was a gentleman, a good plav bike but. regardless of Honda's ads. not a race bike.

Being somewhat eccentric, but knowing what I want for an off-road machine. I decided to build one to fit mv needs and desires.

Much of mv riding is done in the Mojave Desert and Baja, but I occasionally head for the mountains and dodge trees. High speed desert demands long travel suspension, the mountains not so much. Around 1 1 in. at both wheels suits mv

needs. As the project took shape I decided to use onlv the engine and combine it with parts I felt were superior. Cost, for once, would be a secondarv consideration, something I had always wanted to do.

The most important part tff'a race bike af ter engine selection is the frame. I called C&J Racing, the people who made the frames for most of the four-stroke Hondas that have won in Baja. Yes. thev already had a frame for the new XR engines, made from chrome-molv steel, with a choice of head angle and brackets to mount stock items like the seat. tank, etc.: or set up for a Honda CR tank and seat, or just about any wav the purchaser wanted it. Thev claimed a 12 lb. weight reduction and increased strength. I ordered one w ith 29 of rake, a 21-in. front wheel, a kick stand pivot, brackets to mount a Honda CR tank, seat and rear fender. 1 1 in. of rear w heel trav el, tapered steering head bearings. Honda red paint job and a tab on the swing arm ( more about this later). Deliverv time would be about three weeks, time to assemble the numerous other parts needed for such a project.

from past experience I knew what a hassle dialing in forks could be on a custom bike. Seemed logical to use forks that offered adjustable damping and air caps. DC Racing received mv next call. Thev earrv KYB Prolane forks. Beautiful billet aluminum lower legs, billet aluminum triple clamps, adjustable rebound damping, air caps, and over 1 I in. of travel are features of the Pro I a ne forks.

Because the machine was going to be used at high speeds much of the time. I chose Yamaha YZ wheels and brakes. Some people claim the YZ brakes are touchv but I have always liked them and thev stop well. A stock YZ backing plate was used in front, a stock I f brake backing plate for the rear. Using the I f backing plate at the rear eliminated the need for a statie arm. something I always seem to snag on rocks and trees. Also wheel removal is simple and fast. The quick disconnect If rear brake linkage was also used on the stock XR brake cable. Stock spokes don't make it on a Baja bike so the wheels were sent to DC for eight-gauge, gold anodized spokes and gold D.I.D. rims.

Shock choice was easy. I had just finished a long range test on a Maieo 450 Magnum. Works Performance shocks were used on the Maieo for the whole year. Thev

had thousands of hard miles on them w ithout a failure or oil change, and action was still perfect. Gil Valeneourt. ow ner of Works Performance, received mv third telephone call.

Availability of an engine and other necessary parts was uncertain, so I decided to order a complete XR500 use the things like engine, engine mounting bolts, skid plate. GDI. head pipes, brake pedal, shift lever, wiring looms, breather hoses, and foot pegs, then sell the rest. Might be cheaper than buying all of the needed pieces separately. Will be easier anyway. I assured mvself.

A couple of anxious weeks passed. DCS had laced the w heels and I collected them and the forks. While I was there I got a pair of their chrome-molv Suzuki-bend handlebars. A 3.25-21 Metze 1er tire and Barum natural rubber tube went onto the beautiful gold front w heel. A 4.50-IS Goodyear tire and Barum tube were selected for the rear. A week later the frame and shocks were delivered. I dug into the mountain of parts and assembled all that was possible. Now. if I had the engine . . . finally, the bike arrived. The engine was removed and transplanted into the G&J.

I burned the midnight oil for a week before the bike was finished. Custom machines go together slow lv. I used the stock head pipes and built the rest of the exhaust mvself. BY carefully routing the tail pipe, it wasn't necessary to flatten any part of it f'or tire clearance. A modified Super Trapp was used for a silencer. I removed the bolt that holds the tuning discs together, welded chain side plates around the silencer body and installed springs to hold everything in place. This is a trick copied from Can-Ant. Thev use Trapps and modify them with springs. The springs let the discs move enough to keep carbon from building up. vet hold the pieces together better than the stock bolt. A side benefit is ease of'tuning, as discs can be added or removed in a few secón ds.

The carburetor was replaced with a 37mm Keihin (like the one Honda uses in their optional Power Kit), and a K&N filter was clamped to the Keihin. K&N filters are perfect for Baja type riding. Thev clean superbly and don't require cleaning more than a couple of times a year. Magura dog-leg hand levers and straight pull throttle went on the DG bars. International Motor Sports control cables were installed and Yamaha cable guides routed the front brake cable around a Cibie quartz halogen light. The stock skid plate bolted right on but the rear brake and shift lever needed modification. Both needed to be shortened 3A in. The C&J frame places the footpegs farther rearward. so the brake lever and shift lever needed an equal amount removed from them to bring the footpeg/lever relationship back. The KYB forks bolted on to the frame and a TT500 front axle mated the forks and front wheel. A YZ axle spacer had to be shortened to space everything right, otherwise it was a bolt together deal.

The back wheel proved more difficult. A Yamaha YZ axle was the right size, an IT brake backing plate slipped right into the lug on the sw ing arm, but shimming had to be fabricated from stock IT parts. I decided to use a stock XR brake cable; it also needed modification. The front ball had to be ground down so the cable end could pass through the frame, then a loose end adapted to fit. A bracket had to be made to hold the rear of the cable on the backing plate. Quick change pieces from an IT brake rod slipped onto the stock XR cable, and an IT brake arm completed the quick change rear brake set-up. Because the bike would be used for long rides, a steel rear sprocket was chosen; a 44-tooth IT part. This was later changed to a 40-tooth for more top speed. A Maico Magnum chain guide bolted to the sw ing arm tab and an International Motor Sports chain tensioner roller with sealed bearings bolted to the stationary frame bracket just aft of the countershaft sprocket. A Husky Products O-ring chain and stock Honda CR swing arm pads were used.

Eighteen inch Works Performance Shocks, with triple springs and big reservoirs were bolted on and gave 11.3 in. of rear w heel travel.

Finally, all of the loose parts w;ere gone and a beautiful dirt machine stood in front of me. How' could I take something so beautiful into the dirt? The thought that it might not work also crossed my mind. A couple of anxious hours were spent taking pictures and it was time for a riding test. Hurriedly I put my riding gear on and gave the big 500 a sharp kick, it fired and died. Another kick brought it to life and I blipped the throttle while it warmed up.

Low gear was engaged with a clunk and I rode from mv garage. I'm luck\ enough to live in an area where I can ride dirt bikes without transporting them first. The first eorner convinced me the project had succeeded. The steep steering rake supplied quick steering and gave an agile feel to the 272 lb. (with half' a tank of fuel) bike. The 21-in. front wheel let the rider choose the line through a corner and the front didn't skate or slide in off-camber situations.

Handling on smooth TT-tvpe corners was almost as good as a full fledged I f machine. Bumpy straights and whooped trails could be taken as fast as the rider wanted, like a good two-stroke MX bike. Rider position and control layout were perfect. And the engine . . . smooth controllable power, eve replace.

The bike has about 1300 miles on it as this is written. 900 of them in Baja. 200 on mountain trails. 100 in the area around my home and a 100 mile loop through the Mojave Desert. Evervone who rides it makes the same comment: “Doesn't feel as heavv as you sav. sure is neat, goes through the bumps like a two-stroke, the engine sure is smooth, how much did it cost?"

Cost was the onlv undesirable part of the package. But I knew from the start it was going to be an expensive dirt bike.

Here's a price breakdown:

C&J HONDAXR500

$3902

Is it worth what it cost? Yes. It works better than anticipated and makes Baja riding pure fun. The 2.2 gal. tank gives a range in excess of 75 mi.; enough when riding with people on open two-strokes that have less range with their 4 gal. tanks. The C&J weighs about 10 lb. more than an IT400 when both are full of gas, so it isn’t a lightweight, but it is 16 lb. lighter than a stock XR500. And it has more of everything—more fork travel, more shock travel, stronger frame, more wheelbase, bigger spokes, thicker inner tubes—but best of all. handling that is hard to fault.