From Stephen Dobson
(This article had several points which I thought deserved clarification, my comments are in red. Please feel free to submit any additional comments.- Eric)

Your Hawk GT's notoriously bad rear end has to go! You checked your wallet yesterday, and the five hundred smackeroos for a Fox shock just weren't in it. You did notice a 'C' note though, and come to think of it, wasn't someone selling a stock CBR900RR shock for less than a hun? Don't just sit there ... run out and buy that shock. For the cost of the shock, a little machining, and about four hours of work, you can be the happy owner of a Hawk with rear shock that is a) better than the one on your bike, b) rebuildable, and c) working better than you imagined.

I have not ridden a Hawk with a Fox shock, so I cannot make a comparison. I can say that the RR shock takes the lumps out of uneven pavement, and reduces the jarring of the pot holes. It will not turn your Hawk into a Gold Wing, but if you wanted an armchair, you are reading the wrong article.

Project: Attach a stock CBR900RR shock to a Honda Hawk GT

Cost: $75US for shock, $15CDN for machining

Time: 4 Hours (Could probably do it again in about 3 hours).

Difficulty: 3 1/2 out of five

Complexity: 2 out of five

Aside

Diffuculty

Complexity

Tools Required: Hex socket set, Torx socket/wrench thing(? size), metric socket set (including 25mm for rear wheel), 10/12mm, 14/17mm wrenches, coarse file, vacuum cleaner.

(No Torx bits are required for this swap, Rear Wheel is 27mm)-E

Optional Tools: Vice, spring compressors

  1. Acquire 900RR shock. I paid $75US for mine.
  2. Wrap tape around the lower mounting point of the shock so that a) you do not lose the spacer that sits in the needle bearings, and b) the machine shop does not machine the wrong end (not a joke)!
  3. Take the RR shock to your favourite machine shop. If you do not have a favourite shop, look through the yellow pages for some, and pick a bunch in close proximity to one another. Machine shops are a little like motorcycles; when one shows up, others are not far behind. Visit the shops (you will not get anywhere by phoning them), and ask for quotations (prices, not Shakespeare). I picked the one with a Harley parked out front, friendly staff, and the best price ... that's motorcycle friendly for you. [Halton Tool & Fabricators Ltd. Dave Fryer @ 905-335-6978 in Burlington, Ontario]
  4. hole (closest to the preload adjuster) to 11.9mm, or 0.470in. so that the top of the existing (smaller) hole in the RR shock remains as the top of the new hole they mill for you. This will shorten the shock by a couple of millimeters as the RR shock is longer than the Hawk shock. The ride height will still increase, but it would increase more were the hole drilled straight through.
  5. Most people drill the hole through the old center, this allows this to be done on an ordinary drill press, the difference this makes in ride height is not enough to make this worth the effort of milling. If you are very worried about not increasing ride height look into the '96 RR shock which is shorter than the 93-95 models. Also I suggest 12.0 mm as my bolt measured at 11.9 mm. If you do take your shock to a machine shop for milling you should probably have them mill the width of the eye down to the required level, this will save a lot of work with a grinder or file later. - E
  6. Ride your bike for a couple of days while the shock is sitting around the machine shop waiting for its turn on the mill.
  7. Fetch the shock from the machine shop. Do not forget the magic words - you might want them to do something for you again!
  8. Return to your garage or workplace, and place the bike on the centre stand.
  9. Remove the seat, battery, and gas tank.
  10. Remove the four bolts that hold the rear cowling to the bike. Carefully pull out the four cowling locators pressed into the subframe. Pull the cowling up and rearwards a few inches while gently pressing the sides away from the subframe. Rest the cowling on top of the subframe.
  11. Twist the brake light holders out of the cowling, and rest them on the frame. Take this opportunity to check that all the bulb filaments are in good order, and that the bulbs are securely in the holders
  12. Remove the nut and bolt that attach the right footpeg mount to exhaust (stock exhaust).
  13. Remove the two bolts that attach the right footpeg mount to the frame. Leave the footpeg mount hanging.
  14. I was able to do this without dismounting the right hand footpeg using a hex bit on my 3/8 socket wrench. -E
  15. Detach the fuel filter rubber holder from the bracket attached to the frame. Remove the bolt and spacer that hold the bracket to the frame.
  16. At the rear wheel (right side) remove the dust cap, cotter pin, and single nut that holds the rear wheel onto the hub.
  17. Make sure the exhaust pipe is cool enough to hold your hand on without having to remove it (unless you wanted too)! Carefully swing the wheel to the right and rearwards until the rubber of the tire is against the brake rotor. Do not allow the rotor to touch the rim, or you will scratch the rim. The aim is to get the rotor to touch the sidewall as far away from the rim as possible. Slowly, simultaneously pull the tire to the rear, and swing the back of the tire to the left. Watch to make sure the rim does not touch the locators or nuts on the hub, or you will scratch the rim. The tire will push the exhaust pipe out of the way, and the tire will come out smoothly. This technique takes a bit of practice, but is quite effective. Honda tried to explain it in the shop manual, but they do not do a very good job. Rejoice and revel in the glow of really easy rear tire removal.
  18. Or remove the end can of your aftermarket muffler and pull the wheel strraight off :-). - E
  19. Remove the two lower bolts securing the rear sub-frame to the frame.
  20. Loosen the two upper sub-frame mounting nuts and bolts.
  21. Unless the stock exhaust is a problem you should not have to touch the sub-frame. - E
  22. Use the correct Torx socket to remove the bolt that attaches the shock to the swing arm. With the right footpeg mount free to swing out of the way, this task is much easier. I would tell you which size Torx to use, but mine is not marked so I really don't know.
  23. Remember to catch your swing-arm and have something handy to set it down on when removing that first bolt. - E
  24. Use two 17mm sockets to remove the nut and bolt that attach the shock to the frame (at mounting posts).
  25. Lift the rear subframe (it will pivot at the upper mountings), and pull the shock out from between the swing arm and the rear mud-guard. N.B. Honda recommends removing/lowering the subframe and removing the shock by lifting it out between the subframe upper rails.
  26. You might want to take the two shocks to a (friendly) motorcycle shop as this step and the next one are a little tricky. Remove the spring from the Hawk shock. I did this by wrapping my Hawk around a hydro pole (slide into the pole so that the pole hits the cases just behind the crank). [Hit & run by stolen car used in an armed robbery -- wrong place at the wrong time]. This destroyed the motorcycle completely, but I did get the spring off the shock! Less severe approaches are available. [Honda recommends: Set preload to softest, set shock absorber in hydraulic press with tool 07967-KE10000, and compress until stop ring can be removed. Remove stop ring, unload spring, and everything comes apart. (Disregard the following if you want to keep your old shock intact. - E) Shock disposal: center punch damper case 15mm below top surface of shock. Support damper in a vice. Enclose the damper, and a drill with a sharp 2-3 mm bit in a large (inflated) plastic bag. Drill a hole in the shock to release the nitrogen. Warning: Wear eye protection, and do not get hit by escaping oil under pressure. There should not be any oil if you drill it correctly. You may now throw away the shock]
  27. Please note disassembling springs is dangerous work. An 1100 lb/in spring stores a lot of energy and if it gets loose, can become quite the dangerous projectile. If you have any concerns over this it is probably best left to your local dealer or mechanic. - E
  28. Remove the spring from the RR shock. Hint: Adjust the preload to its lowest setting (one), compress the spring with a spring compression tool, push the brass coloured retainer toward the spring, and remove the two semi-circular retainers. Release the spring compression tool slowly, and remove the brass coloured retainer and spring. Voila.
  29. Check the Hawk spring. The free length (unloaded) sevice limit of the spring is 148.3mm. Put the Hawk spring on the RR shock, and replace the retainers as they were when you started. You will not need any special tools for this job, as the shorter Hawk spring can be compressed sufficiently by hand. Make sure the preload adjuster at its lowest setting anyway.
  30. The reason the RR shock can be reassembled by hand is because the free length between spring seats on the RR shock is 9.5 mm longer. You are giving up approximately 100 lbs. of preload unless this is corrected. If you are of larger stature this may be a problem. The correct thing to do is to fashion a spring seat spacer of 9.5 mm. On the flip side it may be possible for those of lesser stature to keep the RR spring on the shock and just use it as is. Fox shocks have much lower rates than stock for all but the heaviest riders. If anyone knows what the stock RR spring rate is drop me a line. - E
  31. Spacer Detail: ATTENTION **This is currently unproven**, I will post details after I complete this project. - E
  32. Place a small thin file on the air box. Turn the RR shock upside down, move the bracket that held the fuel filter aside (up and to the right side of the bike), place the top of the shock (currently closest to the ground) on top of the mounting posts as if you were going to slide it in to check the fit. It is obviously too wide! Grasp the thin file that is on the air box. Mark the top of the mounting posts on either side of the top of the shock (currently resting on the mounting posts). Put the RR shock aside.
  33. Or if you have a set of vernier caliper (cheap $2 plastic job from the hardware store is fine) measure the difference in eye width between the RR shock and the Hawk shock and remove that much material from each side of the shock eye. -E
  34. You are now ready for a healthy thirty minute workout! Place some newspapers, or rags under the shock's upper mounting holes. Turn on the vacuum cleaner, and place it so that most of the suction occurs underneath the upper mounting point. Use the coarse file, to remove aluminum from the mounting posts to the points you marked in the previous step (about 1.5mm from each side of the mounts). Try to avoid covering your motorcycle in metal shavings by sucking them up with the vacuum cleaner or catching them with the rags. Intermittently try to push the top of the RR shock into the widening gap you are making. When the shock slides between the mounting posts you are finished! If you manage to complete this task in less than half an hour, you should definitely spend less time at the gym, and more time riding your bike!
  35. Again having your friendly machinist mill the eye down is probably the hot ticket, but a grinder or coarse file can also be used. Note, if you use a grinder watch the heat build up in the shock, you may want to wrap a damp rag around the shock to help cool it. Also if using a grinder it has been suggested to wrap the shock body near the eye with tape, this will help prevent or minimize any nick on the shock body. You should make sure the inner eye is wider than the rest of the eye, either mill the perimeter further down or grind a chamfer from the center out (I used a Dremel tool).- E
  36. Stephen had some additional comments: If you want to recommend modifying the upper mounting of the RR shock, you should probably describe it in some detail. There are 4mm of material that need to be removed. This means that the person doing this has to cut into the rubber isolator with a mill. The metal gets hot, and fatigues the isolator. Secondly, the inner eye must be wider than the rubber, and the holder (metal around the isolator) so that the shock is isolated from the frame by the rubber isolator. (Also prevents the eye from binding in the frame -E). The shock will be less effective if this is not taken care of. I realize that other people have taken your approach, but I felt the detail (and cost) required in milling the top of the shock properly was greater than using a file to widen the space in the frame. I was also interested in having more steel and less aluminum at the mounting point.
  37. Not sure how much isolation this rubber in the eye actually gives, it is EXTREMELY hard and very thin once inside the eye. The opposite eye of the shock provides much larger part of the isolation chores. -E
  38. Relax after the workout, but do not have a beer yet!
  39. Remove the tape from the bottom of the shock. Lift the rear subframe and insert the RR shock between the mudguard and the swing-arm. Push the shock mostly into position, but not quite. Do not draw analogies between what you are doing, and what farmers do or you will never look at your bike the same way!
  40. Orient the RR shock so that the remote reservoir banjo on the shock is to the rear (away from the rear cylinder of motor).
  41. The remote reservoir banjo bolt should end up on the top left of the installed shock. - E
  42. Juggle things around until the remote reservoir is somewhere good. I have not found a 'good' place yet, so let me know if you do. I tried all kinds of things. I currently have the reservoir resting on the large triangular sections that lead up to the shock mount. You will see what I mean when you try this for yourself. Another possibility I considered as beside the shock, and tied to the subframe. The latter is probably better as it keeps the reservoir farther away from the hot engine, but is less accessible.
  43. Many people have settled on installing the remote resevoir next to the rear master cylinder on the right hand side of the bike. -E
  44. Insert the LOWER bolt through the swing-arm and shock, and tighten with the Torx socket (45Nm or 65Nm depending on which page you read the spec., but went with 45Nm).
  45. Insert the UPPER bolt through the frame hole, and upper hole in the shock, and bolt it up tight (65Nm).
  46. Affix the remote reservoir in the location you wish in the manner you wish. Unfortunately the length of the hose does not allow a lot of options.
  47. Assembly is the reverse of disassembly, but no beer yet. N.B.: Honda recommends the following torques: Subframe Mounting Bolts (40Nm), Rear wheel nut (120Nm), Right footpeg bolts (22Nm), Muffler Mounting bolt (27Nm), Gas tank bolt - Front (12Nm), Gas tank bolt - rear (22Nm), Fuel Filter bracket bolt (22Nm).
  48. Whether you have lifted the stanchions in the triple clamps or not, now is a good time to adjust them again! I started at the stock height, and then lifted them about 5mm to lower the front end. I usually remove the two instrument cluster bolts (8mm socket) to undo the upper stanchion pinch bolts. [N.B.: Honda recommends the following torques: Lower stanchion pinch bolts (50Nm), Upper stanchion pinch bolts (11 Nm), Stock Handlebar pinch bolts (27Nm).]
  49. Stop reading these instructions and GO RIDING.
  50. Now that you are back from riding, feel free to have a beer! Congratulations on your success.

The bike will lean over more on the side stand, but seems stable enough. My new 160/70-17 Metzler rear touches the ground when the bike is on the centre stand. I noticed an increase in ride height with this tire but with this shock, I am even higher (no preservatives). Metzler does not make the 160/60-17 any more, so I might just have to switch back to a 150 at my next tire change.
(Not sure what Metzlers Stephen is running, they do make a 160/60-17 in the MEZ1&2 series, this is the F2 rear tire size that many people run. BTW, the 150/70-17 also touches the ground on my bike, hope to have a little air gap after the 160/60 goes on next week.) - E

Happy trails one and all.