1.
Feeler Gauges--Each cam has different specifications look at the valve clearance information for your cam of choice and you need feeler gauges in that range; my write up lists the 04/05 HRC Cam specs.
2.
Vice Grips--shown in install pictures; others use a vice.
3.
Zip ties.
4.
Hot Cams shim kit-- or a local dealer that stocks shims...the Hot Cams kit is great to have around.
5.
1/4" drive metric sockets.
6.
3/8" drive metric sockets.
7.
Metric end wrenches.
8.
Side cutters--to remove the zip ties with? Razor knife?
9.
Slip-joint pliers--come in handy to work with the clamps on the fuel line.
10.
Metric Allen wrenches.
11.
Allen tipped sockets--Either one will work both is best!
12.
Helper. A few of the steps involve two people unless you are a lot more coordinated and limber then I am.
13.
3/8" Torque wrench.
14.
Locktite.
15.
Needle nose pliers.
16.
Moly paste.
17.
Motor oil.
18.
Container--to mix the moly/oil 50/50 solution in.
NOTE: If there is more then one bolt holding anything on that you are removing follow this procedure. Example: There are 3 bolts holding the valve cover on, put your socket on bolt #1 and barely break it loose, then bolt #2, then bolt #3, then remove bolt #1, then #2, and finally #3. DO NOT remove #1 before you break #2 and #3 loose. If there are 4 bolts follow the same procedure using a crisscross pattern. The same goes for tightening, install all 3 bolts and hand tighten, then cut the torque spec in half and start with #1, then #2, finally #3. Then reset your torque wrench to the full amount and repeat. If the torque amount is high, like 40 ft/lbs, then start at 10, then 20, 30 and finally end at 40...Do not just cut a large amount like that in half. Use this procedure anytime there is more then 1 bolt…it may take a little longer but not in comparison to a broken bolt or stripped threads. If you have any questions regarding this process please email me.
I would highly recommend you do not perform this install without the factory Honda Repair manual 61HP101.
1) Remove the seat, rear plastic, and finally the front plastic.
***Plastic removed***
2) Remove the gas tank.
a) Ensure the gas is turned off.
b) Remove the screw holding the petcock and remove the lever and fuel mark plate.
c) Remove the hose from the bottom of the tank to the carburetor, remove the 2 bolts securing the tank, the two tank straps, and lift the tank off.
3) Remove the PROTECTOR, TANK HEAT (LOWER) (the plastic piece below the tank).
*** PROTECTOR, TANK HEAT (LOWER)***
4) Remove the Spark Plug boot and the Spark Plug.
5) Remove the 3 bolts holding the valve cover on and remove the valve cover.
6) Remove the Crankshaft Hole Cap to set the motor to Top Dead Center (TDC). TDC is achieved when the two marks align.
***Remove this bolt to align the marks to TDC***
7) Once you have achieved TDC (you can do this by moving your R forward in gear) you need to secure the cam chain to the sprocket with two large Zip Ties.
***Note*** There are two TDCs on a 4 stroke engine, make sure your cam lobes are pointing to the rear of the quad like the picture.
***Zip Ties installed***
8) Remove the two Allen head bolts holding the sprocket to the camshaft. I found this to be very difficult as they are secured with lock-tite. Get a good pair of leather gloves and one person needs to grab the sprocket and hold on for dear life. Person number two needs to insert your Allen wrench and tap it with a hammer to break them free.
***New method*** Insert your Allen wrench and put quad in gear and have person 2 step on rear brake to hold cam sprocket in place.
***Here are the two Allen bolts in the sprocket***
9) Cam Chain Tensioner…there are different thoughts on removal of this. Here is what I did and I found it very simple. Take the end bolt out of the tensioner and insert a small flat head screwdriver. Turn the screwdriver clockwise until it stops. All of the tension should be removed from the chain and you can slide the sprocket off. Do not let go of the screwdriver! Ease it back turn by turn until it is free…it is spring loaded.
***Insert flat head and turn clockwise to release tension***
At this point I would recommend you check the clearance on your valves. I wish I would have checked mine before I removed the cam. It is not necessary but I wish I would have known.
10) Remove the four bolts holding the cam assembly.
***Remove these 4 bolts***
11) Steadily lift of the cam assembly taking care not to drop any of the shims into the motor. The assembly is positioned with bosses just work it back and forth gently and lift up at the same time and it will come off. If any of the shims come off make sure you place them back on the correct valve.
***Here are the shims***
12) Remove the decompressor bolt from the cam assembly. I used a pair of vise grips but some have used a vice. The vice grip method worked wonderfully.
***Remove this bolt (decompressor)***
***Here are the vise grips I used (two person job)***
13) Remove the snap ring and the cam shaft will slide out.
***Remove this snap ring and the cam will slide out***
14) Slide the HRC Cam in and reinstall the snap ring. Apply Lock-Tite and install the decompressor bolt. Torque decompressor bolt to: 18 lbf-ft.
I used Lock-Tite #243. It is an oil-resistant medium strength formula (blue) readily available at the parts store. I consulted Lock-Tite and my dealer on which product to use.
15) Reinstall the cam assembly and torque the four bolts to 10 lbf-ft.
16) Use a feeler gauge and check your valve clearances. HRC clearances are:
Exhaust: .28 mm +/- .03 mm
Intake: .16 mm +/- .03 mm
***Note*** There are two TDCs on a 4 stroke engine, make sure your cam lobes are pointing to the rear of the quad like the picture.
***Checking one of the Intake valves***
***Checking one of the Exhaust valves***
After you check all the valves you may need to make shim changes. The easiest way to explain this is find the correct thickness of gauge where it will slide in an out with just a little tension or pressure on the gauge. All of the shims are numbered according to how thick they are. It sort of works backwards, if you can properly fit a .220 mm (exhaust valve example) gauge in then you are too tight even though it is a smaller number then the required .28 tolerance. Therefore, you add a smaller numbered shim to increase the amount of space so the larger .28 gauge will fit. In the above example if a .220 fits then you probably need to drop .06 on the shim. So if the factory shim is a 215 then you need to get a 209. It is not an exact science because I was still .02 off from dead on .28 mm. I worked mine a while with different shims and all the valves ended up dead on.
17) Check the clearance on the decompressor arm: HRC clearances are:
Decompressor: a* + .25 mm +/- .02 mm.
a* = adjusted exhaust valve clearance.
Basically take the exhaust valve clearance you have and add .25mm +/- .02mm to get the clearance for the decompressor.
18) Mix your Molybdenum and motor oil in a 50/50 solution and apply to the top off the shims, lobes on the cam, rocker arm and lifters. I used Moly Paste, my Honda dealer did not have anything else, but it worked great.
***Moly/motor oil solution***
19) Ensure you are at TDC, turn the screwdriver in the camshaft tensioner fully clockwise and reinstall the cam sprocket and chain. Ensure the alignment marks line up, (there are two marks on the sprocket and two on the camshaft holder) apply Lock-Tite and torque the sprocket bolts to: 14 lbf-ft. You can now remove the Zip Ties.
***One of the cam gear marks (there is another on the right side)***
***Alignment mark on the cam assembly (there is another one on the left side)***
20) Now begin reassembling your 450R.
Torque Specifications for Re-assembly:
Head cover torque: 7 lbf-ft.
Spark Plug: 17 lbf-ft.
Crankshaft Hole Cap: 11 lbf-ft.
