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Discussion Starter · #1 · (Edited)
I had a bit of a 'sort out my front end' morning on the bike. After I fitted the fork brace I wanted to do something about the sag in my springs. The CB/R's come with woefully soft springs, like a lot of entry level bikes.

Ideally you dont want the bike sagging more than 3/4 inch under its own weight without rider on board. Mine was sagging 34mm or 1 and 3/8th"

To do this job ideally you need a front paddock stand that fits in under the steering stem and releases all load off the forks. The ones that lift under the bottom of the forks dont do this - obviously!

Before removing the top cap I suggest running one layer of electrical insulation tape around the aluminium hex to stop you marking it with your 17mm socket. Use a socket or ring spanner so you spread the load over all points of the Hex rather than a open ended spanner or even worse using a shifter/adjustable wrench!



Once the cap is off you can easily pull out the OEM preload spacer that is made from very thin tubing. You can either throw it away and put in a longer piece of pipe the right diameter (maximum of 30mm) or just add spacers to the top of the OEM spacer. Stacking 1/8" washers is one way of doing it but I used PVC pipe of the right diameter as I have access to a lathe and was able to turn the length of the pipe down neatly until I got the right length. I did put one steel washer in tho as that OEM tubing is really thin walled and sharp and I was worried about it cutting into the PVC pipe.
Looking at the photo below you have from the right: The OEM preload spacer that sits on top of the springs/ the steel washer I added/ The PVC spacer I turned down/ The Aluminium top cap.





So, by adding 1/2" of spacer material I was able to reduce my sag down to 17mm (11/16th") .
I could feel it straight away which I wasn't expecting, my ride height was slightly higher and a lot of that initial mushy plushness in the early part of the stroke was gone. Better through the bends where your on and off the gas without the front end diving so much under a closed throttle.
As usual this isn't a cure all and it doesn't change your spring rate which is still too soft on the standard springs.
If your interested in spending some coin on your bikes handling then have a look at DaBinChe's Youtube clips on fitting Racetech springs with emulators.
 

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I had a bit of a 'sort out my front end' morning on the bike. After I fitted the fork brace I wanted to do something about the sag in my springs. The CB/R's come with woefully soft springs, like a lot of entry level bikes.

Ideally you dont want the bike sagging more than 3/4 inch under its own weight without rider on board. Mine was sagging 34mm or 1 and 3/8th"

To do this job ideally you need a front paddock stand that fits in under the steering stem and releases all load off the forks. The ones that lift under the bottom of the forks dont do this - obviously!

Before removing the top cap I suggest running one layer of electrical insulation tape around the aluminium hex to stop you marking it with your 17mm socket. Use a socket or ring spanner so you spread the load over all points of the Hex rather than a open ended spanner or even worse using a shifter/adjustable wrench!



Once the cap is off you can easily pull out the OEM preload spacer that is made from very thin tubing. You can either throw it away and put in a longer piece of pipe the right diameter (maximum of 30mm) or just add spacers to the top of the OEM spacer. Stacking 1/8" washers is one way of doing it but I used PVC pipe of the right diameter as I have access to a lathe and was able to turn the length of the pipe down neatly until I got the right length. I did put one steel washer in tho as that OEM tubing is really thin walled and sharp and I was worried about it cutting into the PVC pipe.
Looking at the photo below you have from the right: The OEM preload spacer that sits on top of the springs/ the steel washer I added/ The PVC spacer I turned down/ The Aluminium top cap.





So, by adding 1/2" of spacer material I was able to reduce my sag down to 17mm (11/16th") .
I could feel it straight away which I wasn't expecting, my ride height was slightly higher and a lot of that initial mushy plushness in the early part of the stroke was gone. Better through the bends where your on and off the gas without the front end diving so much under a closed throttle.
As usual this isn't a cure all and it doesn't change your spring rate which is still too soft on the standard springs.
If your interested in spending some coin on your bikes handling then have a look at DaBinChe's Youtube clips on fitting Racetech springs with emulators.
When all my parts finally come for my new clip-ons and my stand comes I figured I might as well tackle the forks at the same time. I'm looking into springs, fluid, spacers (like yours), and definitely preload adjusters. I'm looking at all that now to figure the best scenario for my weight 194lbs (quite a big more than you):eek:
 

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Discussion Starter · #3 ·
When all my parts finally come for my new clip-ons and my stand comes I figured I might as well tackle the forks at the same time. I'm looking into springs, fluid, spacers (like yours), and definitely preload adjusters. I'm looking at all that now to figure the best scenario for my weight 194lbs (quite a big more than you):eek:
Good idea changing the springs Mikal. The length of your preload spacer will be affected by how long the aftermarket springs are. When I ordered some Racetech springs for my GSXR recently it turned out they were 9mm (3/8th") longer than the OEM ones so I cut down the OEM preload spacer by the same amount to compensate.
 

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Good idea changing the springs Mikal. The length of your preload spacer will be affected by how long the aftermarket springs are. When I ordered some Racetech springs for my GSXR recently it turned out they were 9mm (3/8th") longer than the OEM ones so I cut down the OEM preload spacer by the same amount to compensate.
Do you remember what KG RaceTech springs you got? I am looking at the .85 or .90kg. Should that match your bodyweight? Or how does the .XXkg convert to stiffness?
I looked into progressives like the HyperPro but I don't think I want progressives.
I'm gonna add a heaveier weight fluid too. I may be wrong but I think the stock oil is around 5w? I was looking at 10w which says its heavy weight.
 

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Discussion Starter · #5 ·
Do you remember what KG RaceTech springs you got? I am looking at the .85 or .90kg. Should that match your bodyweight? Or how does the .XXkg convert to stiffness?
I looked into progressives like the HyperPro but I don't think I want progressives.
I'm gonna add a heaveier weight fluid too. I may be wrong but I think the stock oil is around 5w? I was looking at 10w which says its heavy weight.
Kg/mm is the measurement of spring stiffness. eg it takes .90 kg (900 grams) of weight to compress the spring 1 mm.

I went for .80kg/mm on my gixxer and they are on the light side but this is a racing scenario and I'm only 130lbs as you know. It's always a bit of a guess.
I would have thought as the OEM springs are .49kg/mm then .85 would be about right for the street.
The guys on the 250R site seem to think they work best with emulator valves but it's more $$$

5w is a very light fork oil and I'd doubt that would be standard, more likely to be 7.5 or 10.

I would go with 10w as a good start. If you change the springs then you dont need to go for real thick oil as it may dampen (slow down) the action too much.
 

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mm/kg is the measurement of spring stiffness. eg it takes .90 kg (900 grams) of weight to compress the spring 1 mm.

I went for .80mm/kg on my gixxer and they are on the light side but this is a racing scenario and I'm only 130lbs as you know. It's always a bit of a guess.
I would have thought as the OEM springs are .49kg/mm then .85 would be about right for the street.
The guys on the 250R sight seem to think they work best with emulator valves but it's more $$$

5w is a very light fork oil and I'd doubt that would be standard, more likely to be 7.5 or 10.

I would go with 10w as a good start. If you change the springs then you dont need to go for real thick oil as it may dampen (slow down) the action too much.
Ugh I hate suspension. It's 1 thing I could never wrap my head around, I always let someone else do that work. It's complicated.
Basically since I'm raising my forks up, which will bring the nose lower, so I wanted to stiffen the shocks just a bit. Like I would do on the pro-link in the back, just up it a notch or 2.
Maybe I'll just insert a piece of PVC and washer in there like you did instead of getting all crazy with this thing.
 

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I have a PVC cutter. I plan to put in a piece of PVC a bit longer than what @kiwi rider has in his photo. I also plan on getting a set of preload adjusters like the ones in this photo so that I can 'fine tune' it without having to keep reopening the fork and putting in or taking out pieces PVC all the time
 

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I have a PVC cutter. I plan to put in a piece of PVC a bit longer than what @kiwi rider has in his photo. I also plan on getting a set of preload adjusters like the ones in this photo so that I can 'fine tune' it without having to keep reopening the fork and putting in or taking out pieces PVC all the time
Be careful with those $20 eBay preload adjusters. Just a heads up try threading them first with no spring tension on them to make sure they're cut right. GL
 

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Be careful with those $20 eBay preload adjusters. Just a heads up try threading them first with no spring tension on them to make sure they're cut right. GL
Alright thanks for letting me know! The ones in the picture weren't the ones I was definitely getting just an example. I was looking at the TYGA kit as it comes with metal spacers as well
 

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I had a bit of a 'sort out my front end' morning on the bike. After I fitted the fork brace I wanted to do something about the sag in my springs. The CB/R's come with woefully soft springs, like a lot of entry level bikes.

Ideally you dont want the bike sagging more than 3/4 inch under its own weight without rider on board. Mine was sagging 34mm or 1 and 3/8th"

To do this job ideally you need a front paddock stand that fits in under the steering stem and releases all load off the forks. The ones that lift under the bottom of the forks dont do this - obviously!

Before removing the top cap I suggest running one layer of electrical insulation tape around the aluminium hex to stop you marking it with your 17mm socket. Use a socket or ring spanner so you spread the load over all points of the Hex rather than a open ended spanner or even worse using a shifter/adjustable wrench!



Once the cap is off you can easily pull out the OEM preload spacer that is made from very thin tubing. You can either throw it away and put in a longer piece of pipe the right diameter (maximum of 30mm) or just add spacers to the top of the OEM spacer. Stacking 1/8" washers is one way of doing it but I used PVC pipe of the right diameter as I have access to a lathe and was able to turn the length of the pipe down neatly until I got the right length. I did put one steel washer in tho as that OEM tubing is really thin walled and sharp and I was worried about it cutting into the PVC pipe.
Looking at the photo below you have from the right: The OEM preload spacer that sits on top of the springs/ the steel washer I added/ The PVC spacer I turned down/ The Aluminium top cap.





So, by adding 1/2" of spacer material I was able to reduce my sag down to 17mm (11/16th") .
I could feel it straight away which I wasn't expecting, my ride height was slightly higher and a lot of that initial mushy plushness in the early part of the stroke was gone. Better through the bends where your on and off the gas without the front end diving so much under a closed throttle.
As usual this isn't a cure all and it doesn't change your spring rate which is still too soft on the standard springs.
If your interested in spending some coin on your bikes handling then have a look at DaBinChe's Youtube clips on fitting Racetech springs with emulators.
I had a bit of a 'sort out my front end' morning on the bike. After I fitted the fork brace I wanted to do something about the sag in my springs. The CB/R's come with woefully soft springs, like a lot of entry level bikes.

Ideally you dont want the bike sagging more than 3/4 inch under its own weight without rider on board. Mine was sagging 34mm or 1 and 3/8th"

To do this job ideally you need a front paddock stand that fits in under the steering stem and releases all load off the forks. The ones that lift under the bottom of the forks dont do this - obviously!

Before removing the top cap I suggest running one layer of electrical insulation tape around the aluminium hex to stop you marking it with your 17mm socket. Use a socket or ring spanner so you spread the load over all points of the Hex rather than a open ended spanner or even worse using a shifter/adjustable wrench!



Once the cap is off you can easily pull out the OEM preload spacer that is made from very thin tubing. You can either throw it away and put in a longer piece of pipe the right diameter (maximum of 30mm) or just add spacers to the top of the OEM spacer. Stacking 1/8" washers is one way of doing it but I used PVC pipe of the right diameter as I have access to a lathe and was able to turn the length of the pipe down neatly until I got the right length. I did put one steel washer in tho as that OEM tubing is really thin walled and sharp and I was worried about it cutting into the PVC pipe.
Looking at the photo below you have from the right: The OEM preload spacer that sits on top of the springs/ the steel washer I added/ The PVC spacer I turned down/ The Aluminium top cap.





So, by adding 1/2" of spacer material I was able to reduce my sag down to 17mm (11/16th") .
I could feel it straight away which I wasn't expecting, my ride height was slightly higher and a lot of that initial mushy plushness in the early part of the stroke was gone. Better through the bends where your on and off the gas without the front end diving so much under a closed throttle.
As usual this isn't a cure all and it doesn't change your spring rate which is still too soft on the standard springs.
If your interested in spending some coin on your bikes handling then have a look at DaBinChe's Youtube clips on fitting Racetech springs with emulators.
I had a bit of a 'sort out my front end' morning on the bike. After I fitted the fork brace I wanted to do something about the sag in my springs. The CB/R's come with woefully soft springs, like a lot of entry level bikes.

Ideally you dont want the bike sagging more than 3/4 inch under its own weight without rider on board. Mine was sagging 34mm or 1 and 3/8th"

To do this job ideally you need a front paddock stand that fits in under the steering stem and releases all load off the forks. The ones that lift under the bottom of the forks dont do this - obviously!

Before removing the top cap I suggest running one layer of electrical insulation tape around the aluminium hex to stop you marking it with your 17mm socket. Use a socket or ring spanner so you spread the load over all points of the Hex rather than a open ended spanner or even worse using a shifter/adjustable wrench!



Once the cap is off you can easily pull out the OEM preload spacer that is made from very thin tubing. You can either throw it away and put in a longer piece of pipe the right diameter (maximum of 30mm) or just add spacers to the top of the OEM spacer. Stacking 1/8" washers is one way of doing it but I used PVC pipe of the right diameter as I have access to a lathe and was able to turn the length of the pipe down neatly until I got the right length. I did put one steel washer in tho as that OEM tubing is really thin walled and sharp and I was worried about it cutting into the PVC pipe.
Looking at the photo below you have from the right: The OEM preload spacer that sits on top of the springs/ the steel washer I added/ The PVC spacer I turned down/ The Aluminium top cap.





So, by adding 1/2" of spacer material I was able to reduce my sag down to 17mm (11/16th") .
I could feel it straight away which I wasn't expecting, my ride height was slightly higher and a lot of that initial mushy plushness in the early part of the stroke was gone. Better through the bends where your on and off the gas without the front end diving so much under a closed throttle.
As usual this isn't a cure all and it doesn't change your spring rate which is still too soft on the standard springs.
If your interested in spending some coin on your bikes handling then have a look at DaBinChe's Youtube clips on fitting Racetech springs with emulators.
Thanks Kiwi Rider for the mod! Wow, i cannot believe the handling difference, didn't think it would make that much difference. I carved up the the hills on my normal ride, it usually takes around 2 hours, shaved about 20 mins off the ride. The bike handled awesome.

I made 2 x 14mm washers, out of a cylindrical piece of steel i found, i dropped them on top of the spring, under the the thin pipe spacer. If i want to make minor adjustments later i can just add more normal sized washers to it.
I am happy with the result, never done suspension b4 like Mikal, but glad i gave it a go. I will now do this to my cb300f and see the difference.

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This goes out to anyone if you want a set of heavy duty fork spring for the CB300f--CBR 300 FREE let me know just pay the postage $20 USA only- I had them in my 300F a few years back and the new owner was a light weight so I changed them out back to stock they are good if you weight over 200lbs-if I remember right they are Sonic 95 cost me $110
 

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Discussion Starter · #13 ·
Thanks Kiwi Rider for the mod! Wow, i cannot believe the handling difference, didn't think it would make that much difference. I carved up the the hills on my normal ride, it usually takes around 2 hours, shaved about 20 mins off the ride. The bike handled awesome.

I made 2 x 14mm washers, out of a cylindrical piece of steel i found, i dropped them on top of the spring, under the the thin pipe spacer. If i want to make minor adjustments later i can just add more normal sized washers to it.
I am happy with the result, never done suspension b4 like Mikal, but glad i gave it a go. I will now do this to my cb300f and see the difference.

View attachment 35026 View attachment 35027
Pleased you got a nice improvement. I could never use a heavy piece of steel like you though, the added weight would play havoc with my OCD tendencies. :giggle:
That's a generous offer of @motorboy, pity your not in the States.
What part of Thailand are you in? I've done some riding in the far North, there's some awesome winding roads up that way and the traffic levels are light as well.
 

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Not sure what your reading I am in the states as in the USA
 

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Discussion Starter · #15 ·
Not sure what your reading I am in the states as in the USA
Yeah I know, I was 'talking' to the OP who's in Thailand. If he's a heavier rider it would be a good score for him.
 
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