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measuring fork tubes

Information on forks/springers/shocks
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54panman
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measuring fork tubes

#1

Post by 54panman » Wed Mar 26, 2008 5:33 pm

hey all, im trying to figure out how to measure my fork tubes with out completely taking apart my bike! i think there either +4 or +6 over either way i hate them and need to shorten them!!! so i need to figure out what length i need -4..-2.. stock.. +2......... i want a stock look with 60's nacelle and cow bells..... what info do you need to help thank panman



old1955
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#2

Post by old1955 » Thu Mar 27, 2008 1:01 pm

Howdy I don't know if this helps, but , Just off the top of my head, standards tubes are 20 1/4 inches long. This may give you a starting point.

fourthgear
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#3

Post by fourthgear » Thu Mar 27, 2008 2:51 pm

We had a thread on this a while back , check out the knowledge base . If you want I will take another measurement of mine with the weight of the bike on the front end or take one of yours and say where your measurement was from where to where.

1950Bobber

Fork Tube Lengtth

#4

Post by 1950Bobber » Thu Mar 27, 2008 3:32 pm

I'll try to help you out here:

Meaure your tubes from the very top portion of the slider (Fork leg if you will!) to the top of the fork tube not to include the fork cap.

Stock length should be 12.5".

You would add in 2" increments for extended tubes, for instance if your front end is 2" over, the measurement I'm pointing out would be 14.5", 4" over is 16.5", etc.

Hope this helps...

Jim "1950 Bobber"

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#5

Post by Guest » Thu Mar 27, 2008 3:35 pm

AND...old1955 is correct at about 20.25 " for stock OEM tubes.

VPH-D
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#6

Post by VPH-D » Thu Mar 27, 2008 5:14 pm

IIRC, measure from the center of the lower tree stainless cover hole to the center of the axle. This should be 20 1/2 ".
VPH-D

54panman
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#7

Post by 54panman » Thu Mar 27, 2008 9:21 pm

hey yall thanks for the help... i have searched the knowledge base and did nt come up with the answers i needed!!! measuring from the top of the tube (below the top clamp) to the rubber on the lower leg is 17" and 33" to the axle center. im going to keep the lowers for the disk break set up! having never torn down a set of fork tubes how far into the lowers does the tube go? thanks panman
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VPH-D
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#8

Post by VPH-D » Fri Mar 28, 2008 5:16 pm

That is not a Hydra Glide fork. It is a Showa unit from the late 80s or newer. It may also be an aftermarket unit. The trees are more narrow than a Glide, and may also have a built in rake. That set up probably works real nice, though...
VPH-D

54panman
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#9

Post by 54panman » Mon Mar 31, 2008 6:02 pm

hey vph-d your right it is a later front end i havent pulled the fender to see if the lower legs are marked yet... and the clamp is also aftermarket...12" across... my late model nacelle will bolt right up to the top clamp (its threaded to accept it) but the lower clamp either has to be changed, modified or i have to use the c.c. adapter bracket i was told about!!! i've come to the conclusion these tube are 6 over! but im no good at math and geometry ect so... the frame rail at the rear of the tranny sits 4.5" off the ground and front just before the wishbone is right about 7.5-7.75"--- 3" diffrence!!! now with angles and rake and tube lengths ect i would think if if i installed stock or 2 over tubes the frame would sit at a down ward angle in the front!!!! please correct me cause i hope im wrong... there are not many folks that deal with pans around here and 98% of my local shop dont want a thing to do with ya if its not a newer bike!!! thanks for the help

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#10

Post by VPH-D » Tue Apr 01, 2008 5:30 pm

Is the frame raked, can't tell from the photo.

Can you tell if the trees are raked? A side photo of the whole bike with the forks turned to the front would help to ID. Some FXWG and aftermarket forks were raked 1 1/2 degrees.

What is the measurement from center of axle to center of non existant lower tree fork cover mount hole?

VPH-D

54panman
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#11

Post by 54panman » Fri Apr 04, 2008 6:13 pm

the measurement from center of axle to center of non existant lower tree fork cover mount hole is 27" as far as the triple tree im not sur if it is raked or not!!! looks pretty square to me but then again im not 100% sure how to tell check the pics thanks for the help
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#12

Post by VPH-D » Mon Apr 07, 2008 4:34 pm

27 1/2" means you have 6' over tubes. You have a peculiar frame, the neck has been replaced, but there is no evidence of a neck lock. How about a photo of the rear axle area?

If you want to try, you can check the look you will get by sliding up the tubes. Remove top tree, block up the bike so the front wheel is in the air.
Loosen the lower tree pinch bolts enough to slide the forks up say 4" or 6", tighten pinch bolts and set the bike back down on the ground. This way you can see what the bike will look like with less fork extension.

Be aware the brake hoses will be too long, and speedo cable, if driven off front wheel. If you do decide to lower the bike back to stock, that front pipe is going to drag, meaning a new system or maybe just a front pipe, depending on what system you are running.

VPH-D

54panman
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#13

Post by 54panman » Mon Apr 07, 2008 11:29 pm

hey vph-d thanks i really appreciate your help! its not a stock frame if that is what you were thinking! it unfourchantly its a poco!!! i'll take the top tree off and run the tube through to get an idea... how far do the tubes go into the sliders? so i can get as close a final measurement as possible? thanks jay

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#14

Post by VPH-D » Tue Apr 08, 2008 5:07 pm

Just take a sharpie pen or something and make a mark on the tubes right at the place where the tube comes out the top of the bottom tree. Loosen the pinch bolts and slide fork assy. up, say 4 or 6 inches. Tighten the pinch bolts, and set the bike back on the ground. How far the tubes go into the sliders isn't relevant to this operation. Doing this will show you what the bike will look like with less or no extension. Try it, and see how you like the low look.
VPH-D

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