has anyone tried more than one set of fork springs?

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After reading several members results on the sonic 1.2 springs I jumped on the band wagon and got me a set.
Comparing the ride to the too soft front springs, the new springs felt great....however...after a few hundred miles are was growing very tired and sore from the bumps and jolts going over any type of expansion crack or seam etc.
Rich ar sonic springs was very generous and offered to send me some softer ones 1.1 and even included a return shipping label in the box. I found his customer service to be outstanding!
I installed the new springs last night with 140mm spacers, one washer, 7wt oil @125mm depth.
The results were dramatic!!!
This bike has NEVER handled so well before! It feels like my old st1100 and rolls into turns with ease.
I cannot feel any jolts or bumps through the bars anymore and feels like I am floating on air.
I guess it pays to try several different things once in a while and not just settle for the first thing you try just because everyone else liked it.
 

CruSTy

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Thank you once again IGOFAR for an other useful contribution. It will save me some trial and error money. I have the Sonic 1.2 springs and while they are a great improvement over the way to soft stock springs they are just a little bit harsh. They are great for pushing hard in the twisties. I try to keep the tank full to help load the front more. Mine were free so I definitely got my moneys worth from them. I was considering 1.1 springs and am glad to hear your results are positive. May have to give them a try. Just FYI I'm 6'2 and 220# do about 50% 2 up riding.

Chuck
 
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dduelin

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Check the Race Tech spring rate calculator if you want an accurate suggestion for springs rate before buying. The Sonic one suggests the same 1.2 spring for everyone over 111 lbs. That's a dead giveaway.
 

mlheck

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Yes, Sonic and Racetech are no where close on spring rates. I weigh 170 lbs. and ride a 1300. I started with the 1.2 then the 1.1 then went to the .90 that was recommended by Racetech. I found the .90 gave me a good ride and support.

Sonic only lists the 1.2, 1.1, and 1.0 for the ST, but they have a CBR spring that is the same size and comes in a .95 and .90.
 
OP
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Igofar
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Check the Race Tech spring rate calculator if you want an accurate suggestion for springs rate before buying. The Sonic one suggests the same 1.2 spring for everyone over 111 lbs. That's a dead giveaway.
:plus1:
 
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This bike has NEVER handled so well before! It feels like my old st1100
Yikes, as someone who has never found the st1100 to be something to strive for in the handling dept, that comes as a bit of a surprise. I would have thought that with less weight and more years of development under its belt that the 1300 would outhandle the 1100 in stock setup. Anyway, glad you got it to where you like it. Like you describe, fork tuning is a multi-variable endeavor that requires a bit of black magic and luck along with working out the numbers.

Actually, if the mfr does it right and installs adjustable fork caps, a lot of the guesswork becomes much easier at the turn of a screw instead of the old fashioned way we do things in the ST world.
 
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Anybody who has replaced the stock springs and weighs around 150 lbs? Race Tech suggests springs @ .867kg/mm for that weight rider. This translates to a .85 spring as the closest to the calculated value. How was the ride after you put these springs in?
 
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For what it's worth I weigh 180 and use the Racetech 1.0 springs. The .95 were too soft.
 

Throttlejockey

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Anybody who has replaced the stock springs and weighs around 150 lbs? Race Tech suggests springs @ .867kg/mm for that weight rider. This translates to a .85 spring as the closest to the calculated value. How was the ride after you put these springs in?
That is a question I would like to know also.
 

dduelin

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Anybody who has replaced the stock springs and weighs around 150 lbs? Race Tech suggests springs @ .867kg/mm for that weight rider. This translates to a .85 spring as the closest to the calculated value. How was the ride after you put these springs in?
I'm half there with the reply. I'm 150-152 in street clothes. Stock spring rate is .860 but is a progressive spring so this is not the same across the full distance of spring compression.

I first set out to get the sag right with the stock springs and 16mm of additional preload got me 36 mm of sag with the stock springs. Under the hardest of braking I still have about 10 mm of travel left and unladen sag is about 20 mm, both of which suggest the spring rate and preload combination is pretty good for me. Oil level is factory manual level. If I could not get the sag numbers right with preload I would have moved on to changing springs but that was not necessary for me.
 

mlheck

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Setting the correct sag with the stock springs will help if you are on the lower end of the weight table. The stock sag is about 35mm vs a recommended 26-28.
 

dduelin

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Setting the correct sag with the stock springs will help if you are on the lower end of the weight table. The stock sag is about 35mm vs a recommended 26-28.
My stock sag was 47 mm or about 44% of travel. There are individual preferences of course but most guides recommend a rider sag of 30-35 mm or up to 33% travel for street bikes with average fork travel. My target was 33-36 mm.

26 - 28mm seems like to me it might be a little high on ride height for a tour oriented sport touring bike. Race bike maybe or a bike with less fork travel than the ST. I thought you were running about 36mm on your ST?
 

mlheck

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Ok, I'll admit I was a couple of beers into the evening when I wrote that. You are correct, I'm set at 36mm.
 
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I have a set of .95 racetech, stock honda fork oil set at 130mm. At first I was at 32mm front rider sag. But after changing my bars to horizon bars with a more upright position I changed it to 36mm. This gave me a better ride in my humble opinion.
 
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Due to a weepy seal I'm collecting parts to prepare for a front fork rebuild. While it's apart springs will get replaced too. Are the Race Techs worth the extra dollars over the Sonics? Also, Race Tech's calculator indicates for my 235 lbs the 1.0s are the way to go vs Sonics blanket recommendation of 1.2s. Should I trust the Race Tech calculator over the Sonic?
The majority of the time I usually ride solo with minimal cargo; however some extended trips are planned where the bike will get loaded up with gear.
 
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Igofar
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I tried the 1.2 sonic and found them very harsh, so I switched to the 1.1 Sonics and am very happy with them.
 

Reginald

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Should I trust the Race Tech calculator over the Sonic?
I personally like the Race Tech calculator over the Sonic because it is more finely tuned to weight of the rider. I weigh 210 lbs. and the calculator gave a rate between .95 and 1.0. I called Race tech and they had me tell them what I do with the bike. Since I tour more than ride aggressively they suggested the .95 rate springs. So that's what I did and I'm happy with it. On the other hand lots of riders like the sonic springs and they work well for them. So, if the price point is your concern go with Sonic.
 
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I personally like the Race Tech calculator over the Sonic because it is more finely tuned to weight of the rider. I weigh 210 lbs. and the calculator gave a rate between .95 and 1.0. I called Race tech and they had me tell them what I do with the bike. Since I tour more than ride aggressively they suggested the .95 rate springs. So that's what I did and I'm happy with it. On the other hand lots of riders like the sonic springs and they work well for them. So, if the price point is your concern go with Sonic.
I talked to Race Tech and they felt the 1.0 was most appropriate to my weight and style. The price difference is insignificant relative to the work involved so I'd prefer the better quality if there is a difference that makes the Race Tech a better spring. Just wondering what the Race Tech offers over the Sonics.
 
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