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stock fork spring rate?

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Hi,

I'm a newbie here, and just wondering if anybody knows the stock fork spring rate on the 230? Mine is an '07 and I just installed the BBR fork and shock springs, but they are way too stiff for my weight (140 lbs.), so now I've ordered the Works Performance shock (Pro Gasser), but I can't find any Race Tech fork springs that will match up (about a .43 spring rate??), so I'm wondering if I should just stick the stock springs back in (I have the Race Tech emulators)? Any ideas? Thanks so much!

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I'm 195+ pounds in all my gear. I'm running the lighter of the 2 weight springs offered with the Works Performance shock. I'm running the Race Tech Emulators, 10w fluid, with stock springs, 16mm spacers, and 5 turns on the emulators.

Suspension works great! I seldom bottom the suspension, and only when hard into the face of a hill that's way steeper than most would attempt at stupid speeds, and off of fairly big trail jumps.

I've gone the stiffer spring/heavier fluid route and I personally feel the lighter suspension settings work better for the great majority of riding conditions encountered off road.

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That's awesome you're happy with the Works shock (I debated for a long time to get it or not - now I can't wait for it to arrive!) So, the stock fork springs worked good for you? Do you know what spring rate they are? I can't seem to find that info. anywhere. Apparently, for my weight, I'm supposed to get .41 - .44 progressive springs, but Race Tech doesn't make them, as far as I can find out from them so far, and nobody seems to know the spring rate on the stockers. Any input would be very much appreciated!

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Hi,

I'm a newbie here, and just wondering if anybody knows the stock fork spring rate on the 230? Mine is an '07 and I just installed the BBR fork and shock springs, but they are way too stiff for my weight (140 lbs.), so now I've ordered the Works Performance shock (Pro Gasser), but I can't find any Race Tech fork springs that will match up (about a .43 spring rate??), so I'm wondering if I should just stick the stock springs back in (I have the Race Tech emulators)? Any ideas? Thanks so much!

A.43 spring will be way too heavy. I ran .42kg springs on my KTM 525EXC and I weigh 180lbs. You want to get the emulators with minimal preload on the emulator. 360cc of 5wt fork oil. Progressive Suspension fork springs No preload will be needed ( I think ), if you use the emulators. The PS spring is a 16/29lb spring rate. Works great for me. I use 7 wt oil. Run about 80mm rider sag on the shock.

This is a similar setup to what I am running currently on my XR200R (87).

Dwight 👍

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I've tried the Service Manual, and several Honda shops in town, but nobody seems to be able to find out what the spring rate is for the CRF 230 stock fork springs. And they don't make Progressive Suspension springs for the CRF 230, either. I guess I'll just put the stock springs back in (maybe .36 - .40 range??) and dial in the emulators after that. But if anybody out there knows about that spring rate, that would be awesome! Or are there Progressive Suspension springs from a different bike that might match up?

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I don't see why XR200R fork springs won't work. Only 1mm external diameter difference. The same emulator fits both the CRF230F and the XR200R.

Dwight

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Good idea - I'll probably just order the '87 XR 200 springs (my stock springs are 28 mm in outer diameter, and the XR ones are 29 mm - is that correct?), but I was hoping to just use my stock ones, if I could have found out the spring rate. Still, nobody seems to be able to find that out, so maybe I'll just take them to a suspension shop and get them tested. I just thought somebody out there would have known that particular statistic because there are so many CRF 230 people on this forum. Thanks for all your help, Dwight!

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Stock 230 fork spring rate .21/.51 kg/mm.

Dwights spring "16/29 lbs /in" converts to .28/.51 kg/mm. That would be better than the stock spring for most everyone, unless you weigh under 88lbs. :worthy:

Spring rates have been discussed. The search tool works pretty well if you use it.

Try preloading the stock spring. 1" spacer will make huge difference on the progressive spring. It'll work much better than the BBR's.

Good luck!

👍

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Yay - thanks for the info, Toast - now that I know the stock spring rate, I think I'll just try the stockers with the emulators (maybe with a 1" spacer?), once the Works shock arrives, and see how it rides. I have a Hare Scramble race in 2 weeks and so far I'm leading in the Ladies series, so it'll be a good test for the new front and rear set up. Hey, and thanks for the Search info. - I learned a lot more reading through all the posts - hey, I'm new to this stuff, so I guess it takes time. Can't wait for the Works shock to arrive! And I guess I'll take out the brand new BBR front and rear springs, so if anybody out there wants to buy them - let me know! Thanks again, guys!

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Congrats, on doing so well in your races. 👍

FYI: the emulator sits in the bottom of the fork tube with the spring on top of it. It is about a 1/2" thick. So you would only want a 1/2" inch spacer for 1" total. You're light though so you may want a hair less preload. If you use stainless washers it's easy to adjust. Just remove the top caps & add or remove to taste.

Good luck at the hairy scramble! :worthy:

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emulators arrived to Italy so i decided to measure my fork springs.

some numbers:

bike crf230

measured travel 230mm --> 9.0 inches

first part of the travel

mathematical average spring rate: 0.33 kg/mm --> 18 lbs/in

last part of the travel

mathematical spring rate: 0.51 kg/mm --> 28 lbs/in

spring rate measured compressing the spring:

0-20mm --> 0.31kg/mm

0-40mm --> 0.31kg/mm

0-60mm --> 0.32kg/mm

0-80mm --> 0.32kg/mm

0-100mm --> 0.33kg/mm

0-120mm --> 0.33kg/mm

i'm sure that the first part of the travel is not 0.21kg/mm as reported in many web pages. both theoretical and practical numbers say about 0.33kg/mm

i learned something more:

obviously my poor human data aquisition is not error free , however it shows that the transition from soft to hard doesn't happen in the first half of the travel. no 20mm increment is near 0.51kg/mm

0-20mm --> 0.31kg/mm

20-40mm --> 0.31kg/mm

40-60mm --> 0.34kg/mm

60-80mm --> 0.31kg/mm

80-100mm --> 0.36kg/mm

100-120mm --> 0.33kg/mm

these numbers also say that at my weight (145lbs + gear) i'd need a 0.40kg/mm spring with 2-3mm of preload to get 25% of sag.

a reasonably accurate confirmation of my past experiences

Edited by 30x26

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Stock 150 spring rate is .32kg/mm according to racetech so I'd assume it was a tad bigger for the 230

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I can help with spring rates; I have a spreadsheet that calculates spring rates but I need some data.

Measure the wire diameter with an accurate micrometer or digital caliper. I usually measure parallel to the spring's center line.

Measure the outside diameter of the spring, but not near the ends.

Count active coils, this is where coils do not touch adjacent coils. If the spring has different coil spacings like the Progressive Spring, count the active coils for each spacing. Shock springs have few coils so accuracy is important, make sure you count partial coils.

Free length, not as important but can be used as a quick check when sorting springs or to used to calculate preload force.

For those interested I can post the formula or the spreadsheet formula.

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