Click pictures to supersize, however a few pictures have no supersize version.

This page shows fork parts details, including comparos between SOME years and models.

Fork part numbers

CRF150R & RB forks are my primary interest because they were developed for a heavier motorcycle and will thus be more suitable for the relatively heavy CRF230F, and they are still being developed for current year models. I do include CR80/85R & RB info but mainly for completeness.

The complete list is: CRF150R, CRF150RB, CR85R, CR85RB, CR80R, and CR80RB. The R models have smaller front/rear wheels than the RB models (R-17/14 vs RB-19/16). The forks are nearly identical, differing in spring rates, base valves, damper rods, and other minor parts.

CRF150R forks: 2007-2009, 2012-2017
CR85R forks: 2003-2007
CR80R forks: 1996-2002

CRF150RB 2017

Ignoring the spreadsheet for the moment, and just looking at the circled part numbers above, which are the differences over the years, I see:

10 & 11 - probably more teflon or wider band or something else related to longevity/reliability.

8 - change to accomodate 10 & 11; wider or deeper cut-out or some such.

12, 21, 25, 26 - change in #8.

14, 16, 22 - change in valving.

13 - change in 14 & 22.

3 - different spring rates.

I think I'll order oldest and newest 10 & 11 to see what the differences are. Discounthondaparts shows about $12 for a set, so about $34 gets me two sets and shipping. R&D costs for this are tolerable... Plus, I can actually use one set or the other.

Ever mindful of the budget, the 14, 16 and 22 changes are merely hole sizes or something equally low-tech, and not worth checking.

CRF150R CRF150RB 2007-2009 2012-2017

CR80RB 2002

CR85RB 2007

CR80R CR80RB 1996-2002  CR85R CR85RB 2003-2007 (Click to supersize.)

Spring Rate Tester

This is my spring rate tester; a 2' piece of 3/4 conduit clamped in a vise. I have two 25 lb weights to compress the spring with. Measure spring free length, add one weight and measure, then add the other weight and measure again. Plug the numbers into a spreadsheet and viola, spring rate comes out the end.

So why do I need this? Because I buy used forks on eBay and I need to know the spring rates of all those undocumented springs that come in the forks. And I also need to double check springs that I buy to make sure the correct springs get installed in the forks. I'm forever losing track of spring documentation.

The spreadsheets above show that forks for these bikes: CR80R CR80RB CR85R CR85RB
can have stock or optional Honda springs that are rated: .24 .26 .28 .30 .32

The spreadsheets above show that forks for these bikes: CRF150R CRF150RB
can have stock or optional Honda springs that are rated: .32 .34 .36 .38

Or forks can have aftermarket springs.

When you buy used, you never know what the spring rates are for the springs in the forks.

Spring Rates Calculation for several used springs and one new Factory Connection spring in my inventory.