OEM/ Race Tech Fork Spring Rate Question

Joined
Aug 7, 2016
Messages
38
Likes
1
Location
Big Lake, MN
#1
My bike is a 2014 non ES. I put an Ohlins in the rear and looking at the Ohlins cartridges for the front but not sure I like the compression on 1 fork and rebound on the other thing Ohlins did.
Looking thru the factory service manual, fork spring rate is listed as such:
K1 0"-2.95"
K2 2.95"-7.48"
K1 .85 KG/MM
K2 1.22 KG/MM

The spring is a dual rate. I want to get a single rate, stiffer spring (240 lbs with 100+ pounds gear). When I go to Race Tech, their web site says OEM spring rate is .96 KG/MM.
Using Race Tech spring calculator, I put in rider weight (entered 310 lbs) and it suggests a 1.02 KG/MM spring (not available). All springs they list are from .60KG to .80KG. They list springs as force but not distance. I can only assume that their spring rates are KG/MM. With that, their stiffest spring is .80KG (softer than the OEM). What am I missing? I tried calling Race Tech but could only leave a message and waiting to hear back.
Are there other brands of single rate springs everyone likes?
Capture.JPG
 

brddog122

New Member
Joined
Feb 26, 2016
Messages
4
Likes
0
Location
Illinois
#3
Cannon racecraft I believe can make about any spring you need. I used them for springs on another bike and dealing with them was a great experience. If they don't have the spring you need listed give them a call and they can probably make what you need. http://www.cannonracecraft.com/
 
Joined
Nov 15, 2012
Messages
916
Likes
659
Location
Fullerton, CA
#5

bimota

Active Member
Joined
Dec 10, 2017
Messages
364
Likes
206
Location
S Wales UK (Bridgend)
#6
i have a ohlins rear shock fitted 3 months ago with a 170 spring, for my 110kg plus wife now and then 70kg plus panniers rear sorted fine.

i was going to do the forks end of the year and WAS going ohlins route but now have douts, don,t really know much about the forks to be honest rather than buy the £1200 ohlins fork kit i know it would be a hell of alot cheaper just to buy springs but i have NO idea what springs would be right for my forks

any imput would be great i am 110kg kitted and a few weekends 2 up extra 70kg plus a 2 week holiday with luggage as well any ideas what springs i need and where to get live in UK

THANKS GUYS

ROB
 

jrusell

Active Member
Joined
Aug 23, 2017
Messages
171
Likes
184
Location
Dartmouth, Nova Scotia, Canada
#7
I never carry a passenger, but run hard bags with some tools and a few spares all the time. I weigh 210lbs before putting any gear on.
I run a 160N spring on my Yacugar shock and my initial thought was 0.95kg/mm springs would work for me. I am currently running 57-60mm sag front and rear, and want to do the same after the re-springing.

There is a fellow on here close to your weight and he as 0.95kg springs. He mentioned to me he thought they might be a bit stiff. From his comments I am leaning 0.95 or maybe 0.9kg.

I have looked into the Ohlins 30mm kit and they only list 8.0N or 9.0N as available spring options for this kit. 9.0N is approx 0.92kg.mm and I am a bit concerned they might be a bit soft?
I don't want to spend that amount of cash and not be able to get stiffer springs if they a lighter than needed. I suppose you can get custom springs made, but to have a kit like this and only 2 spring options seems stupid. The springs ohlins uses in these forks are not used in any other 30mm kits.

The ohlins springs are 420mm long. I don't know the length of the Sonic springs sold for the Tenere. Possibly they are close enough and could be used as a replacement for the ohlins if they prove to bee too soft. I am not prepared to shell out the cash until I know I have more than 2 spring rate options.

Made several attempts to get an answer from Ohlins if more spring rates are available. Also tried to get info from a local suspension shop I was considering buying the Ohlins kit from. Nobody is willing or able to give me an answer. I think this confirms my suspicions.

If anyone who has bought Sonic Springs can confirm the spring free length it would be appreciated.

For those that have re-sprung their Tenere let us know what rate they chose and the sag they are running.
 
Joined
Aug 7, 2016
Messages
38
Likes
1
Location
Big Lake, MN
#8
A bit disappointed.
I called Race Tech a half hour ago. The person I talked to said he is very familiar with the Tenere and all ADV bikes.
I told him the OEM spring is a dual rate but their web site lists a single rate. He said it was an average. I told him I was 240 pounds and with my extra gear, I listed my weight as 310 pounds. He said the calculator already add +75 pounds. I asked about the correct spring rate as the website only offers softer springs for sale. He said the spring rate is just a rate and depended on how far you compress it. I then asked about the spring rates available are all softer than OEM (.60kg to .80kg). He told me to just pick any spring as he didn't care. I said it's hard to pick a spring when a force is given but not a distance travelled. He hung up the phone.
I have installed 50+ sets of Race Tech fork springs (14 years building road race bikes and suspension). I get the factory dual rate spring was simplified to a single rate but when I need to select a spring, I need to know what amount of force increase there will be over a given amount of compression.
Maybe I'm frustrated being I worked with Race Tech from 1998 to 2007 and now they hang up the phone.
I've been out of the motorcycle industry since 2007. I'm not sure if Race Tech is growing or shrinking. After this call, I'm not sure I will recommend their product.
 

jmz

Member
Joined
Feb 1, 2015
Messages
154
Likes
16
Location
Gonzales TX
#9
When I compared my .95 Sonic springs with a dial caliper to the factory springs the heavy end of the factory springs looked very close to my .95's. I'm 250lbs an have my preload backed out all the way. I also have racetech good valves for comp and rebound.

I feel racetech's calculations or too heavy across the board.

I also tried to get my fork buddy to add more rebound to my shim stack but didn't. I believe I would have been right. For me , Todd at cogent was spot on with his recommendations. He recommended .925 . I also believe I would be a little better at .90 but I won't change now. I really like the way my bike rides now. Especially in the rough stuff. I believe I'm the one jrussel is talking about .

Sent from my SAMSUNG-SM-G890A using Tapatalk
 
Top Bottom