Posts
242
Joined
2/1/2009
Location
Calgary, CA
Edited Date/Time
1/26/2012 12:45pm
Hi Fellows -
I bought a new KTM 300XC (same forks as the SX; WP twin chamber) and am swapping out the fork springs. I bought heavier ones from a reputable suspension tuner who I trust but for various technical reasons that made sense at the time they are springs for KYB forks - apparently WP changed the ID of the fork tubes slightly a couple years back and the KYB ones are a better fit for the ID. of the WP tube. Anyway, the length of these springs is shorter than the stock KTM springs so some plastic spacers were included.
Last night I took it all apart and as I drank my last beer I measured the new springs + spacer vs. the stock springs I noticed there was about 1/4 difference - the new assembly is shorter than the stock springs.
I called today and was told to measure the spring preload on the new springs. My boss came around the corner just as the guy was explaining how to measure this to me and I only caught parts of the "how-to".
Anyway, what am I supposed to measure here?
Is it a given point on the the damping ass'y (up high) when inserted into the fork tube vs. the same point on the damping ass'y once the rebound adjuster is screwed into the fork tube and the spring is compressed due to tightening it all up (not the fork cap, just the bottom end? He said something about 5mm but I have 7mm - what do I do now(?) - assuming I have this measurement done right, and I don't know if I do.
Will I be killed if I bolt it all together and ride tomorrow with 7mm, assuming this measurement technique I am guessing at is correct?
I am posting this on KTM Talk too, in the hopes someone will know what the f**k I am talking about and take pity on me. I want to ride tomorrow.
Thanks if you can help.
I bought a new KTM 300XC (same forks as the SX; WP twin chamber) and am swapping out the fork springs. I bought heavier ones from a reputable suspension tuner who I trust but for various technical reasons that made sense at the time they are springs for KYB forks - apparently WP changed the ID of the fork tubes slightly a couple years back and the KYB ones are a better fit for the ID. of the WP tube. Anyway, the length of these springs is shorter than the stock KTM springs so some plastic spacers were included.
Last night I took it all apart and as I drank my last beer I measured the new springs + spacer vs. the stock springs I noticed there was about 1/4 difference - the new assembly is shorter than the stock springs.
I called today and was told to measure the spring preload on the new springs. My boss came around the corner just as the guy was explaining how to measure this to me and I only caught parts of the "how-to".
Anyway, what am I supposed to measure here?
Is it a given point on the the damping ass'y (up high) when inserted into the fork tube vs. the same point on the damping ass'y once the rebound adjuster is screwed into the fork tube and the spring is compressed due to tightening it all up (not the fork cap, just the bottom end? He said something about 5mm but I have 7mm - what do I do now(?) - assuming I have this measurement done right, and I don't know if I do.
Will I be killed if I bolt it all together and ride tomorrow with 7mm, assuming this measurement technique I am guessing at is correct?
I am posting this on KTM Talk too, in the hopes someone will know what the f**k I am talking about and take pity on me. I want to ride tomorrow.
Thanks if you can help.
Was hoping you could help me out???
Adam
Set the spring in place and then slide youre inned chamber in until it bottoms out, sitting square in the spring seat. I like to measure from the top edge of the outer fork tube (make sure it doesnt move on you, I like to wrap a piece of masking tape around the lower for tube so the outer fork tube can't slide down changing my reference point) to a easy reference point on the inner fork tube. Now, push your inner chamber in and tighten it down with your rebound base nut. Take the same measurement again and subtract. the difference will be your sag.
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