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Discussion Starter · #1 ·
I've just recently come into the possession of a Girvin "Vector" and a "Vector 2" front fork, but have zero tech data on how these forks were originally set up and maintained. Also, I know that the original elastomers will degrade in time and, as a result, modifications were made to the shock as "upgrades", including the switch-over to coil springs, in place of the elastomer elements, but don't know if the original, non-ODS shock lends itself to any coil spring mods.
The "Vector" fork shock I have has a coil spring fitted to it of a 700 lb. rate and just under 3" in free length (as a modification?), but I suspect it's not of the correct free length, since the internal rubber damping piston has been compromised (extruded past it's retainer) by way too much pre-load caused by the spring being at least 1/4" too long in it's free state to fit the shock without being substantially pre-loaded already. That puts a whopping 175 lb. force on the little rubber piston right from the get-go with the pre-load nut on the shaft in it's most relaxed position! I also suspect that the switch to coil springs may be correct for the ODS-style shock, but not the earlier one with just the rubber piston and aluminum retainer, which has at best, only a 1/4" range of pre-load adjustment on the shaft...or someone needs to have manufactured springs with a free length of no more than 2 5/8" or 2 3/4" for the Girvin.
I'm aware of Rapid Descent and Suspension Fork Parts as sources for new elastomers, but where can I get tech info about refurbishing and setting up the original, non-oil-dampened-shock units. I'm looking for the bike fork equivalent of an "owner's manual" or "workshop manual" for these forks. Was anything like this ever available? So far, I've only found info for the ODS shock and lots of "Cross Link" material, but zero for the earliest, elastomer fork systems with the rubber piston internal "damper".
Anecdotal info from people who've lived with these forks (fitted mostly to ProFlex bikes?) would also be very much appreciated, especially as it might relate to the (mostly undocumented?) modifications, if in fact these are the forks which people up-graded back in the day. (I'm still not sure if the Vector or Vector 2 was made in both the ODS and non-ODS varieties.)

Ode
 

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Discussion Starter · #3 ·
The oldest manual on the K2 site ('98) shows a spring rate range of 175 - 250 lbs. for the front Noleen shock, considerably less than the 700 lb. spring installed on my circa mid-90's Vector fork [originally (?) fitted with MCU's and, for sure, without an ODS damper]. Did someone install a rear shock coil spring as an experiment once the MCU's went south?
Near as I can tell, is that there were 3 major versions of dampers for this style fork:
1.) The original silver or black, smooth-walled damper body containing a rubber piston (lubricated?), aluminum retainer with allen cap screw and at least 1 of 2 sizes of loose, rubber spheres resting on top of the piston, which must have functioned as a kind of "bump stop" against the cylinder's upper axle-pivot/plug, which is not sealed air-tight. MCU springs only. Four indents at the shaft end of the cylinder indicate where the shaft guide sleeve is staked in place. 2.) The ODS (Oil Dampened System) with a more conventional oil/piston/calibrated valve assembly which had either MCU springs originally or could later (?) be upgraded with a coil spring (of proper length and rate). The cylinder body (always?) is gold-colored and may have annular grooves or ribs on the outside. The shaft end would need a seal, not just a bushing, to retain the oil. 3.) The Noleen shock with externally threaded cylinder body for adjusting the coil spring's pre-load. Never seen with MCU's. Pressurized to 200 psi with dry nitrogen. Probably not in-expensive.
So my question still is, does the first MCU-type shock/damper ever lend itself to being "upgraded", especially with a coil spring, or can they only be freshened up with new elastomers? Is there a functional difference between a "Vector" and a "Vector 2"? The K2 site has no tech data for this early type fork.

Ode
 

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There's no app for this.
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You need to

spend time on Google, I'm no expert but the information is there for the looking:

There is a safety recall on the Vector 1 and 2 forks: http://www.bikepro.com/recalls/girvin_vect_1.shtml (ahhh, in 1997 or so!!!)

In 1997, Bikepro had probably more bike parts than anyone, and they carried none for Girvin back then.

The spring rate on your bike looks incorrect; bikepro is out of business, but the info should be dead accurate. I suspect your spring is retrofitted and wrongly so.
I'm sure there's more, but this should answer some of the specifications questions you have. I wouldn't try to upgrade, it's easier to become a rocket scientist...that fork and shock are long gone.

http://www.bikepro.com/products/frames/noleen_spec_text/nolgirvin.html

Year: 1995/1996
Model: Vector Fork
Noleen P/N: NR1-GRV96, NR2-GRV96
Other Model Applications: None
-Shock Style availability-
-NR-1: Yes
-NR-2: Yes
-NR-3: No
-NR-4: No
Shock Spring Rate: NB2-200 (140-170)
Additional Rates: NB2-225 (180-220), NB2-175 (110-135)
Shock Stroke: 1.70" Stroke
Long Travel Availability: No, the tire would hit the bottom of the fork assembly
Notes: =
 

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Ode... what did you wind up doing about this?

QUOTE="Ode, post: 6423659, member: 469892"]
I've just recently come into the possession of a Girvin "Vector" and a "Vector 2" front fork, but have zero tech data on how these forks were originally set up and maintained. Also, I know that the original elastomers will degrade in time and, as a result, modifications were made to the shock as "upgrades", including the switch-over to coil springs, in place of the elastomer elements, but don't know if the original, non-ODS shock lends itself to any coil spring mods.
The "Vector" fork shock I have has a coil spring fitted to it of a 700 lb. rate and just under 3" in free length (as a modification?), but I suspect it's not of the correct free length, since the internal rubber damping piston has been compromised (extruded past it's retainer) by way too much pre-load caused by the spring being at least 1/4" too long in it's free state to fit the shock without being substantially pre-loaded already. That puts a whopping 175 lb. force on the little rubber piston right from the get-go with the pre-load nut on the shaft in it's most relaxed position! I also suspect that the switch to coil springs may be correct for the ODS-style shock, but not the earlier one with just the rubber piston and aluminum retainer, which has at best, only a 1/4" range of pre-load adjustment on the shaft...or someone needs to have manufactured springs with a free length of no more than 2 5/8" or 2 3/4" for the Girvin.
I'm aware of Rapid Descent and Suspension Fork Parts as sources for new elastomers, but where can I get tech info about refurbishing and setting up the original, non-oil-dampened-shock units. I'm looking for the bike fork equivalent of an "owner's manual" or "workshop manual" for these forks. Was anything like this ever available? So far, I've only found info for the ODS shock and lots of "Cross Link" material, but zero for the earliest, elastomer fork systems with the rubber piston internal "damper".
Anecdotal info from people who've lived with these forks (fitted mostly to ProFlex bikes?) would also be very much appreciated, especially as it might relate to the (mostly undocumented?) modifications, if in fact these are the forks which people up-graded back in the day. (I'm still not sure if the Vector or Vector 2 was made in both the ODS and non-ODS varieties.)

Ode
[/QUOTE]
 
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