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Old 16th September 2007
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cbnightster - The 12 inch long 412's with a 75/120 spring (I think that is standard) is probably a good choice for your weight. That should raise the rear up about 1 inch for a total travel of 2 inches.

Correction: I double checked the Progressive web site, the 12 inch 412's have a 90/130 spring, the 12.5 inch long to get the 75/120.

To raise the forks, you will have to figure out if HD lowered them with extra rebound springs. If that is true, you will have to take a 1 inch of rebound spring to allow the forks to extend 1 inch. Trying to cram in a heavier main spring or adding more perload will only pull against the rebound springs and not give you the height increase you are looking for. Judging by the feed back on the forum, the standard Progressive spring is better that the stock Roadster fork spring. So far Hoghead has provided the only report I have read of the Progressive fork spring in a Nightster, but the guy still needs to do some fine tuning to get it right.

Taking the forks apart to change the rebound springs in not too hard IF you have the manual and better than average mechanical skills. There are no manuals on line, unless some one posts a copy of a page. If I remember correctly, the only special tools needed are snap ring pliers, and a seal driver. I used pvc fittings as a seal driver. A turkey baster with a long hard copper tube on the end can be used to measure and set fork fluid levels.

One of the problems with short shocks and forks that Whittlebeast and I have found out is that the short travel of the shocks and forks do not allow the spring enough distance to fully transition from the low rate to the high rate. 2 inches of travel is better that 1 inch, but still won't be as good as 3 or 4 inches. So the compromise is ride quality vs style of a lowered look. If you want to get really good suspension, I would recommend raising the suspension all the way.

Another option to consider is using 13 inch shocks combined with 1 inch lowering blocks. I am thinking this may be the only way for a 140 lb rider to get a good ride because the longer shocks have lower spring rates the lighter riders need.

I did not actually measure, but the Nightster forks have about 2 inches of travel and the Roadster have 4 inches of travel.

As to fine tuning, since you are going where no Nightster rider has ever gone before, I'll be happy to offer my services of free advice. But expect to do quite a bit of fine tuning.
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Former Ricor test rider for IAS Shocks, Intiminators and Vibranators. Works Dual Rate fork springs, fork brace, Avon Venom X tires, loosen drive belt, and set frame rails level to floor. See "7 Pages of Suspension" thread in the Suspension Sticky Index. It's official, I am now in the "I've forgotten more than I remember club."

Last edited by XLXR; 18th September 2007 at 04:49..
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