What spring rate should I get if I am 160lbs

jbaum · October 25th, 2015, 11:08 AM

So I got tired of the front end pogoing and am eying stiffer fork springs. What spring rate should I get if I am 160lbs? I will be primarily riding on potholey city streets.

SLOWn60 · October 25th, 2015, 11:24 AM

When was the last time your forks were cleaned and the oil changed?
What are your sag measurements?
Are your forks bottoming?
Pogo'ing is not necessarily because your springs are too soft.

choneofakind · October 25th, 2015, 12:16 PM

Racetech has a spring rate calculator that should get you in the ballpark so long as you're not excessively round or very similar to a flag pole... You should be okay. Check that out, see what it suggests, adjust rate from there on personal preference and riding style.

InvisiBill · October 25th, 2015, 03:07 PM

PreGen Fork Spring Rate Chart is from RT's calculator. Stock NewGen springs could work well for your weight.

Quote:

Originally Posted by SLOWn60

Pogo'ing is not necessarily because your springs are too soft.

If you can reach the controls of the bike, the stock PreGen fork springs are too soft for your weight.

dcj13 · October 25th, 2015, 04:11 PM

One could call or write Klaus at EPM Performance. I'm lazy, so that's what I would do (and have done for my K75).

(732) 786-9777
www.EPMPerf.com
info@epmperf.com

SLOWn60 · October 25th, 2015, 04:12 PM

Quote:

Originally Posted by InvisiBill

If you can reach the controls of the bike, the stock PreGen fork springs are too soft for your weight.

Huh?

dcj13 · October 25th, 2015, 04:17 PM

Quote:

Originally Posted by SLOWn60

When was the last time your forks were cleaned and the oil changed?

And what viscosity fork oil are you using?

csmith12 · October 25th, 2015, 04:42 PM

Quote:

Originally Posted by SLOWn60

Huh?

He means.... unless your 65lbs and 10 or 11yrs old, they are gunna be kinda soft or feel like crap under any kind of real braking, high load peformance cornering or really, really crappy pavement.

imho, If your just kinda cruising/putting around on it then the stock ones are fine enough. But if you got some real crappy pavement that you're riding on, then there is no reason to not set your bike up for that riding environment. I would go 7's and customize damping and feel with oil.

Ghostt · October 25th, 2015, 04:51 PM

Listen to @InvisiBill, get the NewGen springs, and might as well get a NewGen rear shock as well, and be done with it.

Added bonus, http://store.ricorshocks.com/product...20-1001nin.htm

choneofakind · October 25th, 2015, 04:53 PM

I'm 130 lbs and found them to be too soft. Upped to a 0.585 spring (still a little soft) and went with Ricor Intiminators to fix the damping issues. What I ended up with is a really nice street setup that still does well enough with the small amount of track time I get to do each year at my skill level.

InvisiBill · October 25th, 2015, 06:25 PM

Quote:

Originally Posted by csmith12

He means.... unless your 65lbs and 10 or 11yrs old, they are gunna be kinda soft or feel like crap under any kind of real braking, high load peformance cornering or really, really crappy pavement.

imho, If your just kinda cruising/putting around on it then the stock ones are fine enough. But if you got some real crappy pavement that you're riding on, then there is no reason to not set your bike up for that riding environment. I would go 7's and customize damping and feel with oil.

RT's calc says you need ~20% stiffer springs for 65lb even. =)

I upgraded my EX500 with springs about the same percentage stiffer than stock, and the bike is a completely different animal now. Personally, I feel the stockers are so soft, it's to the point of making the bike not operate properly. Sure, it'll work and it won't kill you, but it's amazing to get springs of the proper rate in there, so the suspension actually moves like it's supposed to. It absorbs bumps better. It's firmer in turns and braking. It simply moves like it's supposed to, so it works better in all situations. 0.70kg/mm springs are 59% stiffer than stock - it's a very significant change.

Stock, I could literally feel every seam in the pavement. With upgraded springs and Intiminators, the biggest frost heave cracks now feel like the smallest bumps did stock. My $92 fork springs are the best mod I've done to the bike.

Quote:

Originally Posted by Ghostt

might as well get a NewGen rear shock as well, and be done with it.

I haven't seen much about rear spring rates for the PreGen. But based on the EX500 and NewGen rear suspensions, the PreGen spring is actually a better match for 160 than the NewGen's spring. The PreGen shock is the worst of the three, but going to a too-stiff spring might make things worse. You could put the PreGen spring on a 500 shock to get preload adjustment, but otherwise it's pretty similar.

The DIY GSXR shock doesn't really have any models with a spring in that range, but the ZX10 shock that some SV guys use does. That might fit with comparable modding, but they don't seem to be as cheap.

spooph · October 26th, 2015, 09:32 AM

As others have said - spring calculator:
Click on the Calculator link and put in your info - also, their gold valve emulators will change your world!

http://racetech.com/ProductSearch/2/...250R/1986-2007

InvisiBill · October 26th, 2015, 11:26 AM

Quote:

Originally Posted by spooph

also, their gold valve emulators will change your world!

If you're considering emulators, I think you should at least check out Ricor Intiminators too. In my eyes, they seem like a much more advanced way of handling the problem. I don't think anyone has experience on the little Ninjas with both the emulators and Intiminators for a good direct comparison though.

spooph · October 26th, 2015, 12:20 PM

Quote:

Originally Posted by InvisiBill

If you're considering emulators, I think you should at least check out Ricor Intiminators too. In my eyes, they seem like a much more advanced way of handling the problem. I don't think anyone has experience on the little Ninjas with both the emulators and Intiminators for a good direct comparison though.

Never knew they existed! Really cool that they just drop in. With the race tech you have to drill out the stock dampner rod to negate it completely. I'm also on a newgen which has stiffer springs than the pre-gen anyway...

However, as a single "modification", I would put matching the forks to your weight and riding style as the single best mod that anybody can do...

We all love the 250's because they're agile, no?

jbaum · October 26th, 2015, 09:22 PM

Well the calc said 0.664kg/mm for me. I ended up getting 0.70kg/mm from sonicsprings.

I don't think the oil's ever been changed on this thing, kinda surprised the fork seals have survived this long. Although "pogoing" may have been the wrong word, maybe "excessive fork dive" is the right term.

choneofakind · October 27th, 2015, 06:49 AM

Play with the springs, oil viscosity, and oil level. You should be able to get the dive reduced a little bit without too much effort.

dcj13 · October 27th, 2015, 11:04 AM

Quote:

Originally Posted by jbaum

I don't think the oil's ever been changed on this thing, kinda surprised the fork seals have survived this long. Although "pogoing" may have been the wrong word, maybe "excessive fork dive" is the right term.

How many miles are on the bike and why would you expect the fork seals to leak? My K75 (with Showa forks and 86k miles) has its original fork seals. I have replaced the fork oil a couple of times (and the fork springs once).

If one keeps the fork tubes clean and pit-free, the seals should last a long time.

csmith12 · October 27th, 2015, 11:31 AM

Clean the seals first and run something behind/around the lip of the seal to clean that part too. Many leaks are solved simply by doing that.

dcj13 · October 27th, 2015, 12:26 PM

Quote:

Originally Posted by csmith12

Clean the seals first and run something behind/around the lip of the seal to clean that part too. Many leaks are solved simply by doing that.

Like a piece of 35mm film! (with the holes on two edges).

choneofakind · October 27th, 2015, 01:50 PM

Quote:

Originally Posted by dcj13

Like a piece of 35mm film! (with the holes on two edges).

...dating yourself, old man.

spooph · October 27th, 2015, 02:05 PM

Quote:

Originally Posted by choneofakind

...dating yourself, old man.

you shut your mouth!

I still shoot film.

choneofakind · October 27th, 2015, 02:32 PM

Quote:

Originally Posted by spooph

you shut your mouth!

I still shoot film.

Please refer to Post 20, above

InvisiBill · October 27th, 2015, 04:19 PM

If you don't want to make one of your own, http://sealmate.net/ is another option.

csmith12 · October 27th, 2015, 04:56 PM

Quote:

Originally Posted by spooph

you shut your mouth!

I still shoot film.

spooph · October 28th, 2015, 07:45 AM

yay! Finally got an achievement!

jbaum · October 31st, 2015, 06:45 PM

Quote:

Originally Posted by dcj13

How many miles are on the bike and why would you expect the fork seals to leak? My K75 (with Showa forks and 86k miles) has its original fork seals. I have replaced the fork oil a couple of times (and the fork springs once).

If one keeps the fork tubes clean and pit-free, the seals should last a long time.

I guess my fork tubes were clean. I had 43k.

Anyways, the bike got stolen right after I ordered these. So I guess I won't be able to try them.

dcj13 · October 31st, 2015, 11:16 PM

Aw, man. Sorry for your loss!

csmith12 · November 1st, 2015, 07:03 AM

Sorry jbaum...

pattonme · December 25th, 2015, 10:00 PM

The Intiminators use shims for the compression circuit and orifice damping for rebound. Indeed a better solution than GVE.

Oil viscosity is all over the map, and Ricor should have a recommended value to use. Please note that '5w' or '10w' means absolutely nothing as the following chart illustrates. Unfortunately I don't have a Ricor to examine but I would hazard a guess they call for at least a 30cSt@40 oil.

https://www.dropbox.com/s/en31y0wd9u...ghts.html?dl=0

October 25th, 2015, 11:08 AM	#1
jbaum ninjette.org member Name: . Location: SF Join Date: Aug 2013 Motorcycle(s): ex250 Posts: 15	What spring rate should I get if I am 160lbs So I got tired of the front end pogoing and am eying stiffer fork springs. What spring rate should I get if I am 160lbs? I will be primarily riding on potholey city streets.

October 25th, 2015, 11:24 AM	#2
SLOWn60 n00bie to wannabie Name: Bill Location: St Ives, BC (Shuswap Lake) Join Date: Sep 2015 Motorcycle(s): 2012 250R (Red), 2005 VFR800A (Red), CRF450X (Red), 2012 F800GS (Wants to be Red!) Posts: A lot. MOTM - Nov '15	When was the last time your forks were cleaned and the oil changed? What are your sag measurements? Are your forks bottoming? Pogo'ing is not necessarily because your springs are too soft. __________________________________________________ The Smart Money: #1 - ATGATT, #2 - Training (machine skills and survival skills), #3 - The bike; whatever floats yer boat with the money you have left over
	1 out of 1 members found this post helpful.

October 25th, 2015, 12:16 PM	#3
choneofakind ninjette.org certified postwhore Name: . Location: . Join Date: Feb 2011 Motorcycle(s): . Posts: Too much. MOTM - Feb '13, Feb '14	Racetech has a spring rate calculator that should get you in the ballpark so long as you're not excessively round or very similar to a flag pole... You should be okay. Check that out, see what it suggests, adjust rate from there on personal preference and riding style.
	2 out of 2 members found this post helpful.

October 25th, 2015, 04:51 PM	#9
Ghostt in your machine Name: Scott Location: Summer Shade, Ky. Join Date: Oct 2014 Motorcycle(s): 98 Ninja 250/F12 aka ZX-2R "SERENITY", 91 Ninja 500/A5 aka ZX-5R "Phoenix", 84 Honda GL1200A "SIREN" Posts: A lot. Blog Entries: 25 MOTM - Jun '17, May '16, Mar '15	Listen to @InvisiBill, get the NewGen springs, and might as well get a NewGen rear shock as well, and be done with it. Added bonus, http://store.ricorshocks.com/product...20-1001nin.htm __________________________________________________ *violente et ignorantia* ZX-2R BLOG *Twitter and Instagram = Ghostt_Scott* *I'm not here to change your mind, just to inform.*

October 26th, 2015, 09:32 AM	#12
spooph ninjette.org certified postwhore Name: Spooph Location: Golden, CO Join Date: Jul 2010 Motorcycle(s): '08 Ninja 250R Posts: A lot. MOTM - Oct '15	As others have said - spring calculator: Click on the Calculator link and put in your info - also, their gold valve emulators will change your world! http://racetech.com/ProductSearch/2/...250R/1986-2007 __________________________________________________ My therapist has 2 wheels and a seat. If you are ever in doubt to my tone, please refer to my avatar.

October 25th, 2015, 04:11 PM	#5
dcj13 Participant Name: Dave Location: South of Seattle Join Date: Oct 2012 Motorcycle(s): '94 K75 std Posts: Too much. MOTM - Aug '15	One could call or write Klaus at EPM Performance. I'm lazy, so that's what I would do (and have done for my K75). (732) 786-9777 www.EPMPerf.com info@epmperf.com

October 25th, 2015, 04:53 PM	#10
choneofakind ninjette.org certified postwhore Name: . Location: . Join Date: Feb 2011 Motorcycle(s): . Posts: Too much. MOTM - Feb '13, Feb '14	I'm 130 lbs and found them to be too soft. Upped to a 0.585 spring (still a little soft) and went with Ricor Intiminators to fix the damping issues. What I ended up with is a really nice street setup that still does well enough with the small amount of track time I get to do each year at my skill level.

October 26th, 2015, 09:22 PM	#15
jbaum ninjette.org member Name: . Location: SF Join Date: Aug 2013 Motorcycle(s): ex250 Posts: 15	Well the calc said 0.664kg/mm for me. I ended up getting 0.70kg/mm from sonicsprings. I don't think the oil's ever been changed on this thing, kinda surprised the fork seals have survived this long. Although "pogoing" may have been the wrong word, maybe "excessive fork dive" is the right term.

October 27th, 2015, 06:49 AM	#16
choneofakind ninjette.org certified postwhore Name: . Location: . Join Date: Feb 2011 Motorcycle(s): . Posts: Too much. MOTM - Feb '13, Feb '14	Play with the springs, oil viscosity, and oil level. You should be able to get the dive reduced a little bit without too much effort.

October 27th, 2015, 11:31 AM	#18
csmith12 The Corner Whisperer Name: Chris (aka Reactor) Location: Northern KY Join Date: May 2011 Motorcycle(s): 2010 250 (track), 1992 250, 2006 R6 (street/track), 2008 R6 (track) Posts: Too much. MOTY 2015, MOTM - Nov '12, Nov '13	Clean the seals first and run something behind/around the lip of the seal to clean that part too. Many leaks are solved simply by doing that. __________________________________________________ Goal: Shake A Million Hands \| Look through the corners \| Track Day Prep \| Closest track? \| The Mid-Ohio School
	1 out of 1 members found this post helpful.

October 27th, 2015, 04:19 PM	#23
InvisiBill EX500 full of EX250 parts Name: Bill Location: Grand Rapids-ish, MI Join Date: Jul 2012 Motorcycle(s): '18 Ninja 400 • '09 Ninja 500R (selling) • '98 VFR800 (project) • '85 Vulcan VN700 (sold) Posts: A lot. Blog Entries: 1 MOTM - Aug '15	If you don't want to make one of your own, http://sealmate.net/ is another option. __________________________________________________ * Unregistered, I'm not your mom and I'm not paying for your parts, so do whatever you want with your own bike. *

October 28th, 2015, 07:45 AM	#25
spooph ninjette.org certified postwhore Name: Spooph Location: Golden, CO Join Date: Jul 2010 Motorcycle(s): '08 Ninja 250R Posts: A lot. MOTM - Oct '15	yay! Finally got an achievement! __________________________________________________ My therapist has 2 wheels and a seat. If you are ever in doubt to my tone, please refer to my avatar.
	1 out of 1 members found this post helpful.

October 31st, 2015, 11:16 PM	#27
dcj13 Participant Name: Dave Location: South of Seattle Join Date: Oct 2012 Motorcycle(s): '94 K75 std Posts: Too much. MOTM - Aug '15	Aw, man. Sorry for your loss!

November 1st, 2015, 07:03 AM	#28
csmith12 The Corner Whisperer Name: Chris (aka Reactor) Location: Northern KY Join Date: May 2011 Motorcycle(s): 2010 250 (track), 1992 250, 2006 R6 (street/track), 2008 R6 (track) Posts: Too much. MOTY 2015, MOTM - Nov '12, Nov '13	Sorry jbaum... __________________________________________________ Goal: Shake A Million Hands \| Look through the corners \| Track Day Prep \| Closest track? \| The Mid-Ohio School

December 25th, 2015, 10:00 PM	#29
pattonme ninjette.org member Name: Matt Location: Northern VA Join Date: Dec 2015 Motorcycle(s): Lots Posts: 32	The Intiminators use shims for the compression circuit and orifice damping for rebound. Indeed a better solution than GVE. Oil viscosity is all over the map, and Ricor should have a recommended value to use. Please note that '5w' or '10w' means absolutely nothing as the following chart illustrates. Unfortunately I don't have a Ricor to examine but I would hazard a guess they call for at least a 30cSt@40 oil. https://www.dropbox.com/s/en31y0wd9u...ghts.html?dl=0

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