2002 CR450
Too Tech Suspension has extensively tested the CR 450 on and off the track. The bike has fantastic potential. It suffers from a few handling traits which are easily handled by the suspension knowledge we have gained since opening in 1982. Feel free to contact me with your thoughts.
2002 CR450 REVIEW
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TYPICAL COMPLAINTS |
TECHNICAL REASONS FOR TYPICAL COMPLAINTS |
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Front end is too harsh |
Overly aggressive twin chamber pressure spring raises compression operating pressures too high for all shaft speeds resulting in harsh hydraulic action. |
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Bike won’t turn |
Showa compression valving is designed to hold front end up high in the stroke Valving is not optimized for enough dive to promote turning. |
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Front and rear don’t seem balanced |
Front fork springs are not balanced with rear. For lighter riders (180#'s and less, the fork springs should be softer. For heavier riders between 190 and 210, the shock spring should be stiffer. For riders 220 and over, both the shock and fork springs should be stiffer. |
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Bike tires the rider too quickly |
Both fork and shock compression are stiffer than needed. This causes the rider to squeeze the bars and stay tense in preparation for the next compression spike. Revalving is required for a plusher more compliant ride. |
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Too much arm pump |
Forks don’t flow over sharp bumps, compression is too stiff. This causes the rider to grip the handlebars too tight, which promotes arm pump. |
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Rear is nervous – kicks up off jumps |
Shock rebound is too fast at the top of the stroke. The overly progressive valving causes the rebound to be too fast on top and/or too slow at the bottom. |
2002 CR450 SET UP
I wrote this information for Dirt Rider Magazine to document the changes we made to their test bike. You should see a story in Dirt Rider Magazine soon that was based on this information
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Too Tech recommends that both front and rear suspensions be modified at the same time so both ends can be coordinated and work together. For the purpose of the article, we made the changes one at a time so the improvements could be documented separately.Stage 1 Modification: Fork compression valving was modified to allow faster transition into the dive or turning position.
Results: This produced a slight improvement in turning and arm pump but overall action remained slightly stiff.
Stage 2 Modification: Twin Chamber pressure springs are changed to reduce system-operating pressures.
Results: This produced a significant change in fork action allowing the forks to flow through the sharp bumps rather than deflecting. This had a huge effect at eliminating fatigue at the end of the day.
Stage 3 Modification: Installed lighter fork springs to allow the front end to dive farther
Results: This further improved turning and made the front feel plusher. This was especially effective in making the bike turn on flat terrain. (See rate suggestions below)
- At this point the forks were soft and plush and would initiate a turn easily.
Stage 4 Modification: Shock compression was relieved to allow wheel to compress easier on square edges. Additionally, the rebound was slowed at the top of the stroke.
Results: The compression changes allowed the bike to enter turns more smoothly without kicking up or upsetting the line choice made by the rider. The rebound changes made jump take-offs more consistent and improved straight-line stability.
- These changes complemented the fork changes and provided a more balanced overall suspension.
TEST DAY
We then had a test day at Glen Helen to review the changes first hand at the track. Rick from Too Tech and others participated by riding many laps and making adjustments as the day progressed. The hydraulic damping seemed very good so only very minor clicker changes were made. Most changes involved balancing the suspension using spring preload and fork height adjustments.
First Observation: Front end felt slightly harsh.
Action: The front compression damping was turned 2 clicks out to soften action.
Results: The action was smoother and plush, issue resolved.
Second observation: Rear end kicks up slightly and the bike is a bit twitchy.
Action: The shock rebound damping was slowed down by turning the adjuster in (clock wise) 1 click.
Results: The rear end was calmer and followed the terrain better.
Third Observation: Front end dives too much at the end of the straights under heavy braking.
Action: Pull the front forks down in the triple clamps to hold the bike up.
Results: The bike stayed up at the end of the straights providing more confidence under braking. The bike still turned plenty sharp enough.
Fourth Observation: The bike kicks up slightly when entering downhill turns with large braking bumps.
Action: Change the rear race sag from 98 to 102 mm of race sag.
Results: The bike could be pushed harder into the turns without kicking up and loosing control. Again the bike still turned plenty sharp enough.
Note: The valving adjustments Too Tech makes to the front forks allowed us to make stability changes to the front end that might have cause turning problems for other suspension company setups.
For experimentation and general suspension knowledge, we made the following
Hydraulic changes to determine if our clicker settings were optimized.
Experiment #1: Question – Could the rear rebound be any slower? Would this offer more stability?
Action: We slowed the rear shock rebound 2 clicks clockwise.
Result: The rear end began to "pack" slightly. Because the rebound was not fast enough to allow the suspension to return to it’s original ride height before the next bump, the rear end packed down and became slightly stiffer.
Decision: The rebound was slow enough and we returned it to its original setting.
Experiment #2: Question – Could the rear compression be set softer too allow an even plusher ride.
Action: We turned the shock high-speed adjuster out 1 full turn to make the compression softer.
Result: The rear bottomed in the deep whoops and felt a bit soft overall.
Decision: The compression was soft enough and we returned the high-speed adjuster to its original setting.
FINAL ANALYSIS
During the test session, we made several beneficial changes to the bikes balance and clicker settings. The action seemed great but we wondered if it could be better. We experimented with some other adjustments to determine if the settings were truly optimized for this track. We determined they were. Overall we were very happy with the CR450 suspension settings and handling traits on the track.
450 SPRING SELECTION Note: The stock rear spring measures out at about 5.25, not 5.4
Suggestions below are for the average aggressive MX rider.
Older, less aggressive riders should use 1 step softer.
Younger or hard charging riders should use 1 or 2 steps stiffer in the front .
| RIDER WEIGHT | SHOCK SPRING | FORK SPRINGS |
| 150 LBS | 5.2 Kg/mm | .45 Kg/mm |
| 175 LBS | 5.4 Kg/mm | .46 Kg/mm |
| 200 LBS | 5.7 Kg/mm | .47 Kg/mm |
| 220 LBS | 6.0 Kg/mm | .48 Kg/mm |
| 240 LBS | 6.3 Kg/mm | .49 Kg/mm |
| 260 LBS | 6.6 Kg/mm | .50 Kg/mm |
These are tried and tested rates which work well. Each rider is an individual and I often deviate slightly to suit individual preferences. Call or e-mail me with your thoughts and we can pick a package just for you.
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Rick Johnson TOO TECH SUSPENSION