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Discussion Starter #1 (Edited)
Pressure plate Spring/Bearing info Replacement and usage- Stock/Barnett

Spring Pressure on Clutch Pack lbs-

Stock Diaphragm spring 382lb (1FK-16334-00-00)
EBC Diaphragm Clutch Spring 420lb (CSK906)
Speedstar Diaphragm spring 459lb (SPD-5PX09-84-00)
Double stock Diaphragm spring 764lb (1FK-16334-00-00)Custom retainer required)

Barnett Springs ×6 springs
Gold - 450lb 501-75-06005 (MT-05)Standard)
Green - 492lb 501-82-06023 (MT23)
Red - 594lb 501-99-06091 (MT91)

Pressure Plate Bearings and pressure ratings-
(Note- bearings below beginning with 6 are Deep groove ball bearings and bearings below beginning with 7 are Angular contact ball bearings)

Stock pressure plate bearing-
Koyo 6003C4 - (93306-00315-00 Yamaha part number)
1,349lb(6N) Dynamic Load
731lb(3.25N)Static Load

Barnett conversion pressure plate - 511-90-10002
1st generation SKF 6003/C3
1,410(6.27N)Dynamic Load
731lb(3.25N)Static Load

2nd generation VXB 7003B (Redish)Nylon Retainer
(Less friction & less weight = higher speed)
1,439lb(6.4N)Dynamic Load
854lb(3.8N)Static Load

3rd generation VXB 7003B Steel Retainer (Latest)
1,439lb(6.4N)Dynamic Load
854lb(3.8N)Static Load

It seems that some bearings may not be produced or sold which can then be replaced with use of different brand or design.

Possible reasons of failure can be from poor oiling to the bearing, engine oil maintenance, installation, clutch cable adjustments, riding the clutch, over heating or just being that sometimes parts don't always last.

Stock pressure plate bearings have failed aswell as Barnett pressure plate bearings but with the number of failures it's not and should not be a big concern.

A large number of VMax owners using the Double clutch pressure plate springs have not reported failure from that mod so it seems those rated bearings are sufficient in the stock pressure plate as well as barnetts for a replacement bearing.
The Barnett pressure plate bearings have a higher rating then the stock pressure plate bearings so it seems they would also be sufficient in use of higher then rated pressure.
I would think that Barnett does not advise the use of Red springs with their conversion pressure plate due to the provided Static load ratings of the bearings they use to protect them self from blame but it does not prove that they will not work as Many warrior owners aswell as Vmax, Road Star do/did and now use Barnett red springs without bearing failure with all the previous and current bearings.

Every once in a while there will be failures in these as we've seen through the years as with everything but not enough to sway away from use. Just like there is failures with the stock clutch cables with use on stock clutch plates while allot never have issues and even some use stock clutch cables with use of barnett pressure plate without failure. There's also some that have multiple failures with Barnett clutch cables while other/most never have issues at all.

((All my info has been gathered from this, Road Star clinic, Vmaxforum, the members of Vmax,Road Star ,Road Star Warrior, Vxb reps, Bearing dealers, Barnett and Internet))

Barnett P/p throw out bearing replacment

Known Replacment Bearings through the Road star warrior, VMax and Road Star forums for failed or upgraded bearings-

Vxb 6003 zro2 Full ceramic. Verified (10/31/19) still going without issue 7yrs later W/Barnett Pp- Greg Kipp aka ghost pepper)(Currently
Load Ratings Not Known)

Koyo 7003FY (High-Tensile Brass Casting Machined Cage)
1,641lb(7.3N)Dynamic Load
1,000lb(4.45N) Static Load

Koyo 7003c
1,641lb(7.3N)Dynamic Load
1,000lb(4.45N) Static Load

VXB 7003C P5
1,506(6.7N)Dynamic Load
1,101(4.9N)Static Load

VXB 7003B Steel Retainer (VXB Claims the Nylon version has the same specs beside Less friction & less weight = higher speed)
1,439lb(6.4N)Dynamic Load
854lb(3.8N)Static Load

Vxb 6003/6003B
1,432lb(6.37N) Dynamic Load
731lb(3.25N)Static Load

SKF 6003/C3
1,410lb(6.27N)Dynamic Load
731lb(3.25N)Static Load

Timken 6003 C3
1,349lb(6.0N)Dynamic Load
742lb(3.3N)Static Load

Koyo 7003B
1,371lb(6.1N) Dynamic Load
843lb(3.75N)Static Load

Koyo 6003C4 or 6003 - (Yamaha part number 93306-00315-00) (there may also be 6003 with a SH stamp aswell as a 6003c4 with a SH stamp meaning (Special Heat Treated Bearings with Only inner ring SH)
1,349lb(6N)Dynamic Load
731lb(3.25N)Static Load
SH Stamped models may have higher loads.
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