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Discussion Starter #1
Per this thread: http://www.stromtrooper.com/dl650-2012/77540-fork-spring-rate-2012-a.html, I'm ankle-deep in this job.

A few questions:
1. Does the Glee use the same axle bolt as the Wee - 12mm? I need to go get one.

2. How the heck are you supposed to remove the front fender? There are two small hex bolts which thread into what seems to be metal disc behind the plastic. Turning the bolts just spins the disc. There seems to be a channel in the plastic which one can reach up into, but no clearance for any tool I own. I'm a little miffed how terrible this design is.

3. Is the fork oil height still 150mm for the 2012?

4. Sanity check: 290# rider = 1.1kg springs + 15wt oil. The heavier oil is supposed to slow down the damping to compensate for the beefier spring, if I'm understanding it right.

5. Go with recommended spacer length, which looks to mimic stock? Will my high weight mean that I should plan on more pre-load via a bigger spacer, or is that what I'm accomplishing by using the higher-rate springs and a longer spacer will go too far?
 

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FORUM GODFATHER.....R.I.P. PAT
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The axle does take a 12mm tool. The heavier spring handles the job rather than more preload. Your spring manufacturer ought to have info on spacer length and air space over oil.
 

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Discussion Starter #3
Thanks, GW.

The springs are Sonics; for which the instructions seem to be for <=2011 Stroms.

I don't know if anything changed fork-wise, but I'm sure you do.

Also don't know if the 2012 has been around long enough for RichDesmond to have much experience with them (I'm sending him my stock springs so he can measure them, e.g.).

Also also I'm a moto suspension idiot and can use all the help I can get. ;)

I'll rip into them tomorrow once I have the axle wrench and will try to document for the community... assuming I can get the *^$%& fender off, that is.
 

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FORUM GODFATHER.....R.I.P. PAT
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There are differences but it's likely the air space and spacer length will be the same. It appears you'll be the one to let us know for sure.
 

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Discussion Starter #6 (Edited)
Rich, my stock spacer measured 3.938" - I assume this translates to a nominal length of 100mm.

I will get pics up later, but right now my bike is in pieces and I've run into a small issue: the stock springs are about 17 3/8" long; your Sonics are 16 3/8".

The underside of the cap has a washer/ disk cotter-pinned on it, and the cotter pin interferes with the PVC sitting flush on the washer because the PVC's thicker walls cover more of the washer surface than the stock spacer's.

Choices seem to be:
-notch the PVC to "bridge" over the cotter pin. The pin seems to turn with the cap, so screwing the cap on would drive the spacer around, potentially abrading some of it off to mix with the fork oil.
-use the stock spacer and stack a short (1"-ish) PVC spacer on top
-source some different spacer material
-cut down the cotter pin to create some clearance

Haven't decided on what to do yet, taking a break to chew on it a bit.

EDIT: Ok, now I know I needed that break: The cotter pin is just thru the underside of the preload screw to retain the washer so you can't back the preload screw all the way out of the fork cap. I'm going to be brave (and expedient) and just remove the cotter pins, and try and remember to NEVER exceed "5" on my fork preload (I doubt I'll ever touch it again once I'm done with this install).
 

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You can just use the stock spacer. You DON'T want the new spring/spacer to be the same total length as stock, it needs to be a little shorter, otherwise you'll have too much preload and not enough sag.
If you want to use the PVC, cut it to the length in the instructions. You can either pull the cotter pin as you describe, use a small straight cotter pin that you then bend around so it fits inside the PVC, or just put one of the washers between the PVC and the cotter pin.
 

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Discussion Starter #8
You can just use the stock spacer. You DON'T want the new spring/spacer to be the same total length as stock, it needs to be a little shorter, otherwise you'll have too much preload and not enough sag.
Ok, that doesn't make sense to me. The stock arrangement had TOO much sag with a "weak" spring; I'm replacing the with a "strong" spring. All things equal, my sag will get less. Assuming the springs have been matched to my weight, why would I have NOT ENOUGH sag with the same length assembly?

In any case, I wish you'd replied earlier, because it's all back together and I rode it around the block to make sure my front wheel didn't fly off.
Brake dive is noticeably better, not enough miles to judge handling.

I ended up just leaving the cotter pins out.

It's all written up with pics steve68: Fork spring swap.

I'm going to go out and check my sag to make sure I'm not sitting on top. What do I want - 30% of travel for 90% road, 10% tame dirt roads?
 

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Ok, that doesn't make sense to me. The stock arrangement had TOO much sag with a "weak" spring; I'm replacing the with a "strong" spring. All things equal, my sag will get less. Assuming the springs have been matched to my weight, why would I have NOT ENOUGH sag with the same length assembly?

In any case, I wish you'd replied earlier, because it's all back together and I rode it around the block to make sure my front wheel didn't fly off.
Brake dive is noticeably better, not enough miles to judge handling.

I ended up just leaving the cotter pins out.

It's all written up with pics steve68: Fork spring swap.

I'm going to go out and check my sag to make sure I'm not sitting on top. What do I want - 30% of travel for 90% road, 10% tame dirt roads?
The stock setup has enough preload to give reasonable sag with a relatively weak spring. If you use that same amount of preload with the stronger springs you get less sag. So in almost all cases you setup the new springs with less static preload (i.e., a shorter total spring/spacer length) in order to get the sag correct.

40mm is a good total sag number for the Stroms.
 

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A pvc pipe spacer can have its top notched to clear the cotter pin.

For anyone who doesn't know, sag is the measure of how much the front or rear end drops when you sit on the bike, fully loaded, ready to ride, passenger on also if carried. Sag is adjusted with the preload. This gets you in about the middle of the suspension travel so you have less chance of either topping out or bottoming out over bumps. If you can't get the desired sag setting, you need different springs for your loaded riding weight. (And in some cases, even if you can get the sag right, different springs improve the ride.) Here's more:
Suspension Adjustment

While one is messin' with their forks, keep in mind that the fork oil deteriorates with time and heat. After a couple of years or more, there is a sludgy mess in the forks. Removing and draining the fork leg, flushing with solvent (I use paint thinner), drain, flush with light cheap oil (I use hydraulic jack oil), drain, then refill with the correct fork oil is a help. The stock fork oil weight is 10 wt. A synthetic fork oil will live longer and give less change from very cold to very hot.
 

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Sag is adjusted to be at a point where the suspension will not top out or bottom out in use. That is best accomplished at 1/4-1/3 of the available travel rather than half. The forces involving suspension movement are greater in compressing the suspension rather than extending it. 40mm of sag is a good number.
 

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Discussion Starter #12
Ok, an update: "wow" - what a difference:

The brake dive is probably about 25% of what it was - a 75% reduction.

It is definitely more planted. I didn't realize it was "doing" much until I realized I was coming thru corners 15mph faster than normal with zero drama.

The handling is predictable, confidence-inspiring. I think a lot of what I've always assumed was tire squirm or fork wobble (no fork brace) was in fact wallowy, weak suspension.

The ride is not noticeably harsher on "normal" road bumps, but catching a pothole at speed is more jarring.

Punchline: after putting some miles on, I measured my front sag (zip tie method alone, not super accurate).
Static sag is about 10-15mm; fat-arse sag is 24-26mm. That's something like 18% of available travel.

If only I could learn to read/ follow instructions... Guess I'll be chopping the spacers down a bit, or maybe using the stockers.
 

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bear in mind that for my K8 model - actual measured travel for the fork is only no more than 140mm - 30% is 42mm - so around 25% - to 33% is between 35mm to 47mm.

40mm is a good number.

I just use a thin wire instead of cotter pin to clear the spacer -
 
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