Which end is up on progressive fork springs?

I've got down on some notes that the end with the wider space between coils goes down. I can't remember where I got this info so I'm just checking to see if that is correct. I've got a 73 850. Thanks.

Should not make a bit of difference as both ends of spring get compressed but may make some different if there is a better end surface to bare on damper tube cap or less spring coils rubbing on inside of stanchion. I've tended to put closer coil bunch - heavier end to bottom for a bit lower CoG.

The instructions that came with mine said to put the closer wound end at the top, these are the first to go coil bound so fitting this way reduces unsprung weight which is a good way to go.

Increased unsprung weight may be a consideration. But Progressive's main reasoning on this is that their springs are made of a larger diameter wire than most stock springs. The more metal you shove into the oil, the higher the oil level will rise. So they recommend the tighter wound end face up to prevent raising the oil level too much above what it would be with the stock springs installed. Obviously, the spring doesn't care - it'll perform exactly the same whichever end goes in first. But the ride could become harsh if the oil level was too high (air space too small).

Stu

Thanks for the spring insights. Stu maybe putting progressive spring upside down form instructions might help the compliant most have that they dive too much on braking.

hobot said:

Thanks for the spring insights. Stu maybe putting progressive spring upside down form instructions might help the compliant most have that they dive too much on braking.

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Unfortunately, it's the spring that holds up the bike's weight, not the oil. The higher oil level might increase compression damping near full compression, but my hunch is the bike would still suffer about the same braking nose dive unless the springs were changed for something a bit firmer. Either that or a person could fiddle with different lengths of PVC spacers to increase the pre-load.

Stu

Yes Stu, only springs in passive forks resist brake dive to matter. The air space gets pumped out after a few bumps so oil level just short of lock up is best for me.

I've not heard of any but the standard off the shelf progressive springs available that most the heavy braking or heavy riders complain of too soft nose dives.

Ms Peel lucked out two 2x's in the spring department, snagging last of a batch of custom 3 rate progressive springs with rather better action on their own, plus the 1st ever substitution of an extra spring spacer instead of solid ones, that added two more rates, 1/2" of very soft compliance but over an inch of very stiff. I really don't think you can get better bang for the bux than Greg's kit.

Do keep in mind cutting spring shorter stiffens it. So might trim some off current spring then fill in with you own custom rate spacer spring. Half the fun of Commando is the trial and errors learning curves never ending advancements.