Mix and match fork springs

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sthutch
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Mix and match fork springs

Post by sthutch »

Here is a question for you fork wizards. Has any one mixed fork springs of different weights. I have my stock fork springs and a pair of .48's that I got before I learned about this site or much about my bike. I weigh about 210 with all my gear and ride single-track.

I put the .48's in but they seem to stiff. Freddette recommends .42's. If I mix one of each I can get much closer to that. My question is if doing so would cause any damage to my forks or myself. I know I could just spend the dough and buy a new set, but that spoils the fun of experimentation!

Thanks,
Sthutch

1st Bike: '72 Arctic Cat Whisker (rode it to the wheels fell off)
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bufftester
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Re: Mix and match fork springs

Post by bufftester »

It is possible you could do harm to your bike or yourself. By mismatching the spring (and compression rates) you would be putting a lot of stress on the axle and front wheel by extension. Straight line you may not feel anything, so if all you do is drag race it you'll be fine :doh:
sthutch
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Re: Mix and match fork springs

Post by sthutch »

I was wondering about that. Since the springs are exerting different pressure the front wheel will want to rise unevenly, putting serious stress on the fork tubes and axle mount. Sometime ago I was talking to a guy who had used two different springs, but they were much closer together in size.
Sthutch

1st Bike: '72 Arctic Cat Whisker (rode it to the wheels fell off)
2nd Bike: '76 KT250 Trials (gone, but not forgotten)
3rd Bike: '01 KDX200
4th Bike: '96 DS80 (okay, my 9yr old's and it's gone)
5th Bike: '04 RM65 (okay, he's now 10 and it's gone)
6th Bike: '08 KTM 105xc (okay, he's now 13)
7th Bike: '06 KTM 200xc-w (okay, he's now 16)
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diymirage
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Re: Mix and match fork springs

Post by diymirage »

sounds to me like it would be a great set up for circle track :grin:
newbbewb wrote:DIYmirage has it right.


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-2003 Yamaha TTR125-L (wifeys bike)
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royadams
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Re: Mix and match fork springs

Post by royadams »

I find it hard to believe it would do any damage. If the new forks run the spring in one leg any the compression in the other, why could you not run different springs or valving in different legs.
sthutch
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Re: Mix and match fork springs

Post by sthutch »

That is what I was thinking. But before I did this, I thought I'd throw it out to the rest of you. Hopefully someone here has done this type of thing before and can provide a definitive answer.
Sthutch

1st Bike: '72 Arctic Cat Whisker (rode it to the wheels fell off)
2nd Bike: '76 KT250 Trials (gone, but not forgotten)
3rd Bike: '01 KDX200
4th Bike: '96 DS80 (okay, my 9yr old's and it's gone)
5th Bike: '04 RM65 (okay, he's now 10 and it's gone)
6th Bike: '08 KTM 105xc (okay, he's now 13)
7th Bike: '06 KTM 200xc-w (okay, he's now 16)
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gsa102
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Re: Mix and match fork springs

Post by gsa102 »

I would not try it with the stock fork setup, as the new mx bikes with unequal fork springs are most likely stronger around the axle. I would think you would be inviting binding issues as well.
This is my rifle, this is my gun, the YZ to go fast, the KDX is for fun!

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Dekon
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Mix and match fork springs

Post by Dekon »

Just to throw this into the mix, what about trials bikes, they have compression in one leg and rebound in the other. But I don't think I'd mix spring rates in a KDX.
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Gotanubike
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Mix and match fork springs

Post by Gotanubike »

hehe NASCAR might have a few tips for you for asymmetrical suspension setups :razz:

Try replacing the spacer on the .42's or stocks, if you are on conventional forks because I don't know USD forks at all. You could swap out the spacer up top for a longer one for more preload. That would be the cheapest most effective method IMO
1990 KDX200
Bike Profile -> http://www.kdxrider.net/forums/viewtopi ... 61#p136315
Suspension Overhaul(Shock+89-92 conventional forks) -> http://www.kdxrider.net/forums/viewtopi ... 15&t=15255
96'-98' RM125 Showa 49mm fork swap -> http://www.kdxrider.net/forums/viewtopi ... 04&t=16994
KDXrider world map! -> https://www.zeemaps.com/map?group=186158
sthutch
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Re: Mix and match fork springs

Post by sthutch »

Now that seems to be an interesting idea and a lot less extreme!
Sthutch

1st Bike: '72 Arctic Cat Whisker (rode it to the wheels fell off)
2nd Bike: '76 KT250 Trials (gone, but not forgotten)
3rd Bike: '01 KDX200
4th Bike: '96 DS80 (okay, my 9yr old's and it's gone)
5th Bike: '04 RM65 (okay, he's now 10 and it's gone)
6th Bike: '08 KTM 105xc (okay, he's now 13)
7th Bike: '06 KTM 200xc-w (okay, he's now 16)
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