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XR650L Actual suspension travel for XR650L?

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The advertised travel for the stock XR650L suspension is ~11".

I put stiffer springs on both ends of my bike to carry my 240# body. I also changed the fluid at both ends. These mods dramatically improved the handling of the bike, especially in the dirt.

But one thing has bugged me since I got the bike a month ago: it doesn't feel like I'm getting 11" of travel at either end. For comparison, I'm using my test-ride of a set up DRZ400e. That bike felt like a lunar lander – many inches of plush travel.

So I measured the travel of my forks today. To do so, I first unloaded the fork by putting the bike on a stand. Then I recorded the max travel with me bouncing on the front end as hard as I could. I got 5.5" total. (Static sag is 1.5" and race sag is 2".) I was shocked. ?

I'm sure that my rebuild may be fouled up, but seat-of-the-pants suggests similar travel before the rebuild.

So does anybody know what kind of travel they are getting from their XR650L?

And what's wrong with my bike (guesses)?

Note: It is unlikely to be a compression damping issue. I checked. 

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I would think that you cannot achieve max compression by just bouncing, even with significant weight and strength. Try taking on an MX track and hit heavy whoops at 40 mph. If you mark the forks with a paint pen, you should be able to see max travel.

 

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1 hour ago, dbryant61 said:

I would think that you cannot achieve max compression by just bouncing, even with significant weight and strength. Try taking on an MX track and hit heavy whoops at 40 mph. If you mark the forks with a paint pen, you should be able to see max travel.

 

I'll do this within the next few days. I think I'm getting full compression but it doesn't hurt to check. Thanks.

Does anybody have their own set of measurements from their notes or log book?

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One more thing: you should be able to determine max compression from your fork spring spec. There should be a spec length at rest, at full compression, and a spring rate (100#/in. or similar). Determine weight on front wheel, calculate compression distant from spring rate and weight, then rest length - compression - full compressed length. Maybe?

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1 hour ago, dbryant61 said:

One more thing: you should be able to determine max compression from your fork spring spec. There should be a spec length at rest, at full compression, and a spring rate (100#/in. or similar). Determine weight on front wheel, calculate compression distant from spring rate and weight, then rest length - compression - full compressed length. Maybe?

I'm running 0.63KG/mm springs in the forks, which I believe equates to 35.5#/in. I wrote to procycle requesting the spring length data. I'll measure the weights as well. Thanks.

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You're getting only 5.5" of travel right now because you put stiffer springs on there.  I still have the relatively soft springs on my bike and I prefer it that way.  I've never bottomed it out even when riding in a place that used to bottom out the forks on my KTM 990 Adv, which had about 8" of travel.  I'm pretty sure I can get about 8" of travel on my XR just doing hard braking.  The front end dives a long ways.  You can always put a zip-tie around the fork leg to check the maximum compression it has achieved.  It will slide up the leg as it compresses and stay at the maximum position.  Go jump it off of a ten foot ledge or something and you'll see much more of the travel.

One easy way to check the fork travel is to take the caps off of the forks.  You should be able to move them through the full range of travel with the springs not pushing against anything.  I don't know any similar trick for the rear shock, though.

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Just to update: Using the zip tie method and actual road test, I have 1.5" of static sag and 5.5" of compression travel for a total travel of 7". So far less than the 11" claimed but not terrible I guess.

The free length is 20.75" with a rate of 35#/in. I couldn't get the spec for fully-compressed spring length.

So 7" (5" preload plus 2" sag) are req'd to support bike and rider. This leaves plenty of spring travel to achieve the remaining 9" of travel (11" minus 2" sag).

Unless I've done something wrong, this external analysis seems to check. If I'm going to find more travel, I think I'll have to disassemble the forks again.

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