purchased a used 06 rtx. I weigh 250 to 270lbs (w/gear). Do I need to revalve or change the mono spring?
ReX
TY 4 Stroke God
Most likely you will need to do one or both - depending on your riding style.
If you're the type to take it easy over bumps and are looking for a very soft compliant ride you might be able to get away with moving the mono spring c-clip to the 3rd position and keeping everything stock. It will likely be too soft for you though.
If you are a more aggressive rider you'll want to install a heavier spring. Stock the spring rate is 4.5 kg/mm and there are many different spring rates to choose from (see http://www.ty4stroke.com/viewtopic.php?t=22583). The guys I ride with, myself included, all found the 6.5 kg/mm spring ideal. We're all in the 230-255 lb range, ready to ride.
With the heavier spring, the shock valving (especially rebound) should ideally be adjusted to match (the dial primarily adjusts low speed). What you'll find is if a lighter rider (140-170 lbs) tries your sled with the 6.5 kg/mm spring and the stock shock they will experience severe kickback from bigger bumps (kicking the back of the sled up in the air and making the sled unstable).
With your weight (and ours) this problem doesn't occur and the ride is pretty decent with just the spring change.
My shock was revalved in my second season and the increased shock damping combined with the spring made the sled more stable, more solid feeling and able to handle bigger bumps without bottoming while still providing a comfortable ride.
The other option is to keep the stock spring and revalve the shock for much more high speed compression damping. This would in theory give you the best of everything. The problem with this is the shock really has to be perfectly calibrated and there is little margin for error. I would recommend at 250-270 that you go with the spring (assuming you aren't happy with the stock setup).
One final thing to note. After the 6.5 spring combined with the shock revalving, my front and rear pivot arms cracked quite a bit faster than my buddies riding with just the 6.5 spring (same trails same speeds). It took about 4000 miles to get some pretty significant cracks in the front pivot arm and small ones where the shock mounts on the rear. The other guys found cracks in their pivot arms were either very minor (at 4k miles) or didn't see them until about 6000 miles.
If you're the type to take it easy over bumps and are looking for a very soft compliant ride you might be able to get away with moving the mono spring c-clip to the 3rd position and keeping everything stock. It will likely be too soft for you though.
If you are a more aggressive rider you'll want to install a heavier spring. Stock the spring rate is 4.5 kg/mm and there are many different spring rates to choose from (see http://www.ty4stroke.com/viewtopic.php?t=22583). The guys I ride with, myself included, all found the 6.5 kg/mm spring ideal. We're all in the 230-255 lb range, ready to ride.
With the heavier spring, the shock valving (especially rebound) should ideally be adjusted to match (the dial primarily adjusts low speed). What you'll find is if a lighter rider (140-170 lbs) tries your sled with the 6.5 kg/mm spring and the stock shock they will experience severe kickback from bigger bumps (kicking the back of the sled up in the air and making the sled unstable).
With your weight (and ours) this problem doesn't occur and the ride is pretty decent with just the spring change.
My shock was revalved in my second season and the increased shock damping combined with the spring made the sled more stable, more solid feeling and able to handle bigger bumps without bottoming while still providing a comfortable ride.
The other option is to keep the stock spring and revalve the shock for much more high speed compression damping. This would in theory give you the best of everything. The problem with this is the shock really has to be perfectly calibrated and there is little margin for error. I would recommend at 250-270 that you go with the spring (assuming you aren't happy with the stock setup).
One final thing to note. After the 6.5 spring combined with the shock revalving, my front and rear pivot arms cracked quite a bit faster than my buddies riding with just the 6.5 spring (same trails same speeds). It took about 4000 miles to get some pretty significant cracks in the front pivot arm and small ones where the shock mounts on the rear. The other guys found cracks in their pivot arms were either very minor (at 4k miles) or didn't see them until about 6000 miles.
