Fork spring length confusion

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Fork spring length confusion

Postby JezZedexE1 » Tue Aug 06, 2019 7:03 am

I am trying to find out the length of the stock springs! :help All the posts here have different info and seem to have aftermarket sizes but no mention of original ones.

I have 4 pairs of 530mm long springs. I presume that is the stock size. The dimensions for replacement springs I have managed to search out here vary from 460mm up. Then with a spacer of 36mm or so. Vino had 500mm springs he took out. Could they have been NA springs?

This is also mentioned:
free length 460mm, plus a 36mm spacer on top. Installed height including the spacer is 470mm.

How does 460 + 36 = 470? :?

:popcorn
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Re: Fork spring length confusion

Postby DEATH_INC. » Wed Aug 07, 2019 7:31 am

JezZedexE1 wrote:I am trying to find out the length of the stock springs! :help All the posts here have different info and seem to have aftermarket sizes but no mention of original ones.

I have 4 pairs of 530mm long springs. I presume that is the stock size. The dimensions for replacement springs I have managed to search out here vary from 460mm up. Then with a spacer of 36mm or so. Vino had 500mm springs he took out. Could they have been NA springs?

This is also mentioned:
free length 460mm, plus a 36mm spacer on top. Installed height including the spacer is 470mm.

How does 460 + 36 = 470? :?

:popcorn
:beer

I'd suspect they have 26mm of preload.
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Re: Fork spring length confusion

Postby capt42104 » Sat Aug 08, 2020 5:47 pm

More Confusion!

My OEM barn find E2 (1380 original miles) has springs which are 52.705cm[/b][/b]. My "spare" forks off an E1 that had 18K miles which was totaled (rear ended) in 2002 have 50.165cm springs (no spacer). Both have 4mm coils. I recall from the last time I changed out the springs in my long gone E1 and GPz1100 the Progressive brand springs were shorter and came with a PVC pipe spacers. Oh, the coils were thicker springs too. Not sure why the E1 spring is a full inch shorter. The E bike supplement and Base shop manuals are no help in regards to spring lengths as you may or may not know.

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Last edited by capt42104 on Thu Aug 20, 2020 3:15 pm, edited 2 times in total.
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Re: Fork spring length confusion

Postby Betterthanfabio » Sun Aug 09, 2020 12:47 am

Didnt we go though all this a few months ago? I remember measuring my old ones & posting the reasults on here.
You should try to know everything about something & something about everything.
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Re: Fork spring length confusion

Postby Eckhard » Sun Aug 09, 2020 2:16 pm

capt says "has springs which are 52.705mm[/b][/b]. My "spare" forks off an E1 that had 18K miles which was totaled (rear ended) in 2002 have 50.165mm"


Your units seem to be off there. 52.705 mm is 2.075 inches in length. Are you talking about diameter? Or might that be 52.705 centimeters(527.05 mm) that you want to say but your pictures don't show any tools that are that accurate over that length. BTW I don't think a caliper is accurate enough for a 52.705 mm measurement either.
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Re: Fork spring length confusion

Postby capt42104 » Thu Aug 20, 2020 3:16 pm

Eckhard wrote:
capt says "has springs which are 52.705mm[/b][/b]. My "spare" forks off an E1 that had 18K miles which was totaled (rear ended) in 2002 have 50.165mm"


Your units seem to be off there. 52.705 mm is 2.075 inches in length. Are you talking about diameter? Or might that be 52.705 centimeters(527.05 mm) that you want to say but your pictures don't show any tools that are that accurate over that length. BTW I don't think a caliper is accurate enough for a 52.705 mm measurement either.


Darn metrics! I meant CMs on the lengths obviously. I use a tape measure then converted to metric....Sorta.
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Re: Fork spring length confusion

Postby JezZedexE1 » Thu Aug 20, 2020 6:17 pm

1 inch = 25.4mm or 40 thou. :mrgreen: :beer :thumbup ;) :humour
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