Stiffer fork springs

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banner001
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Stiffer fork springs

Post by banner001 »

Hi guys, my fork seals have gone so i need to ge them replaced...bu i am also looking at getting stiffer front springs.

Im not massive, but at ~90kg wih gear on im way over the 68kg "ideal rider" mentioned in the manual, i can find progressive springs, but i can find any replacement linear springs...do such things exist?

i was under the impression that linear was better than progressive...but i might be wrong.

about 10% of the time my bike has the missus on the back so that adds another ~65kg in gear+missus to the suspensions load, so thats another reason for the stiffer springs, can anyone point us in the direction of some stiffer front springs please?
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003
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Tirpitz
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Re: Stiffer fork springs

Post by Tirpitz »

TBH I wouldn't mess about, it's a job for a suspension specialist. Why don't you send them off to be rebuilt to your requirements by someone who knows what they are doing, they will be able to source anything you need? Somewhere like MCT will charge you £200 for the entire job.

You can very easily make a complete gash of suspension. It's not the sort of thing to start swapping internals in unless you absolutely know what you're about. I'm not trying to be clever here but from your earlier posts you don't strike me as being mechanically expert and you could get in a proper mess this this work.
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banner001
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Re: Stiffer fork springs

Post by banner001 »

Tirpitz wrote:TBH I wouldn't mess about, it's a job for a suspension specialist. Why don't you send them off to be rebuilt to your requirements by someone who knows what they are doing, they will be able to source anything you need? Somewhere like MCT will charge you £200 for the entire job.

You can very easily make a complete gash of suspension. It's not the sort of thing to start swapping internals in unless you absolutely know what you're about. I'm not trying to be clever here but from your earlier posts you don't strike me as being mechanically expert and you could get in a proper mess this this work.
Its not that im not mechanically minded, i actually part own a patent on a machine used by david browns in huddersfield (think aston martin 'DB' 9...DB was an homage to david browns who manufactured the gearboxes) that i helped to design and build when i was only 18 years old (is used for self-leveling and self-adjusting <5tonne work-gear shafts for rockwell diamond surface hardness testing)...its more that i have 0 cash, 4 problems, and i dont wanna f***-up my only means of transportation.

in other news i spotted about 7 slightly rough pitted marks on the back of the tube the other day about 3" from the stanchion top, so thats probably whats shagging the seal on the RHS still cant see anything on the LHS though, looking for replacement forks as they will probably be cheaper than 1. getting new stanchions and fitting them, or 2. getting them re-chromed. gonna stick with zxr 400 forks for the time being, not gonna go with the 636 mods, as this way i can keep the original calipers etc...
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003
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Re: Stiffer fork springs

Post by ZX4R-F3 »

Just a thought, depending how much stiffer you want the front end, you could always use a heavier weight fork oil, i think the manual says 5wt, but you could use 7.5, 10 or 15.
It will stiffen up the damping.

Added bonus you don't have to strip the forks to change it, just drain via screw at bottom of fork leg, remove top adjuster and fill with oil.

Good luck with it.
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banner001
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Re: Stiffer fork springs

Post by banner001 »

new forks should be here on the 12th...but the guy has not got the dust covers on...so it still looks like i will need to strip them...why would he run with no dust covers?

if they look crap he's getting them sent back.
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003
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