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Hello everyone, long time reader, first time poster!
I have an 07 with 40,000 miles that I bought last spring from someone who really neglected it. I’m about to tear the forks apart and rebuild them with all new bushings and seals for probably the first time. While I have them apart I wanted to go ahead and make some improvements to the front suspension. Mainly, cut the springs to make them stiffer, (I’m also going to drill and tap a fork drain hole). I’ve been reading up on how to improve the suspension, and I’m getting ready to cut about 4 inches off the springs to bring the spring rate to 0.85. However, I’ve run into a problem that is confusing me and I was hoping to get some advice from you guys:

Before I take everything apart, I wanted to record the baseline specs of the suspension in its stock form. With the front wheel in the air I measured from the lower clamp to the top of the dust cap: 150mm. Me on the bike with gear and using the race tech method I measured 100mm. That gives me a race sag of 50mm, which is 30% of total fork travel. I weigh 150 lbs. What I’m confused about is that this 30% sag appears to be the exact right amount of sag. The front feels really soft, it dives under breaking, and the race tech site says I need 0.85 springs. But my sag measurements tell me that the forks are perfect for me. What do I do? Should I leave everything alone, is race tech wrong?

Thank you! and sorry for the long-winded post!
 

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I comes down to how you ride, As you found out the stock springs are about right for your weight. If your aggressive you may want a set of emulators to control the dive a bit. they are adjustable for your situation.
Them and some heavy weight fork oil should fix you up , unless you race or ride like a racer.
then it's a whole new ball game, and turned to your track.

FOG
 

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Sag and spring rate are 2 different things. Your present (stock) setup has about the right amount of sag but springs that are too soft for your weight. The Racetech spring calculator isn't wrong. It confirms both your personal assessment and the general consensus.....unless you weigh 100 pounds or less, the stock EX springs are too soft. The reason the factory put those overly soft springs in there was to compensate for the cheap damper tube suspension.

I weigh about 160, went through the same process a couple of years ago, and chose 0.80 springs, emulators, and 10 wt. fork oil. I was not only happy with the results, the change was night and day. Less dive under braking, but much more comfortable and controllable on rough pavement in spite of the stiffer spring rate. You are on the right track but while you are in there, spend the extra money for the emulators; you won't be disappointed.
 

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Im 200lbs with (caugh, out) gear and went with a 7.75" cut with heavy fork oil, black pipe filler peice and large metric washers for shims. Rode like a champ.
 

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When I upgraded to stiffer race tech springs and their gold valve slip in dampers I noticed a HUGE improvement. It basically made it ride like a new bike. It was the best mod IMO I made to my 500 when I owned it. Race tech is a great company to deal with as they include everything you need, including thorough and easy-to-follow instructions and metal spacers, etc. and their stuff is of much better quality than OEM original. The first thing I noticed was a front end that did not collapse under hard braking.

The only issue is since the gold valve dampers have hidden inside the fork legs you need to pull them every time you want to adjust. The stock fork legs just rely on small holes that oil is forced through for damping. The gold valve dampers however use more modern and complex spring-loaded dampers that can better cushion bigger bumps while allowing increased slow oscillation damping. Suggest using synthetic fork oil as viscosity, and thus damping, will not change as much with outside temp differences.

If you can find the viscosity of synthetic auto transmission fluid online, people publish tables, you can use it in place of fork oil of a similar viscosity. Amsoil ATF signature series (red label) can be used interchangeably with 10W fork oil for instance.

PS A cheap plastic turkey baster you can buy at any dollar store is an excellent thing to have to set your fork oil level precisely. Just measure from the tip and mark it with a sharpie. Then overfill your forks and suck out the excess oil with this inserted to the mark. A large syringe from a pharmacy (with the needle removed) will do the same thing. Be sure to mention to pharmacist it is for motorcycle maintenance and not heroin addiction.
 
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