uprating your zxr400 forks

Wheels, shocks, forks, frame
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corky
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uprating your zxr400 forks

Post by corky »

maxton

The forks look externally very similar to the 750, but internally there are quite a lot of difference - it is a much cheaper fork inside. One of the big problems with the ZXR400 forks is that the oil is metered at the top of the fork. We modify the forks so that the oil is metered at the bottom of the fork, this gives the fork a much smoother action. We also increase the rebound damping and reduce the compression damping, this helps the bike turn into corners and hold a better line exiting corners. We also fit harder springs to suit your rider weight to stop the forks diving under braking. "

The cost of the conversion is £250 plus VAT and carriage. Seals would be £20 plus Vat and bushes if needed would be £20 plus VAT.

k-tech

For your forks I would recommend one of our 20SSK piston kits. These comprise of complete new compression and rebound piston assemblies with our own design CNC machined piston's, new piston holders, piston rods, shim stacks, check valves and new rebound adjustment circuits to give a much finer and wider range of rebound adjustment.This kit was designed for road and track day use to enhance the damping efficiency of the standard fork and give greater confidence to the rider. The cost of the piston kit is £260.00 inc VAT. Depending on the weight of the rider and the O.E. fitment we would also offer optional rate fork springs to suit rider weight and the discipline the bike was being used for. These optional rate replacement fork springs are £65.00 per pair inc VAT. To fit all of the above we charge £85.00 inc VAT this includes a complete strip and rebuild of the forks but does not include any charge for oil which is £10.00 per litre inc VAT or any service parts needed such as oil seals or bushes. These would be inspected when the forks were dismantled and replaced where necessary.

MCTechnics

Hello there.Really your two choices are new fork springs and oilfor £145.00 with a couple of small mods. Or a re-valvewhich would start from £325.00 as there would be quitea few parts required to improve the rebound side ofdamping. Hope this ok, Darren.

Kais
the zxr400l forks are very basic and apart from a spring change and thicker oil, the only other option is for a complete rebuild making completely new pistons and shim packs, for which you are looking at £5-600,
cheers nick
Last edited by corky on Thu Nov 15, 2007 10:49 pm, edited 2 times in total.
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the-elf
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Post by the-elf »

Umm sounds good. The K tech conversion sounds very good. I would love to try the two side by side to compare. Both are resonably priced (You would die if you knew how much mine cost).

From the Maxton comments perhaps someone should try the ZXR750 forks and compare the two. I would guess these would make a better starting point.
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Red Devil 777
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Post by Red Devil 777 »

Are zxr750 forks the same size (Diameter) as zxr400?

Look a bit like 400L forks

http://cgi.ebay.co.uk/Kawasaki-ZXR750-R ... dZViewItem
Last edited by Red Devil 777 on Tue Nov 13, 2007 9:26 pm, edited 1 time in total.
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the-elf
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Post by the-elf »

I'm not sure, they look the same. Hasn't Kaze got them fitted to his bike?

/edit Just checked and Kaze has the earlier RWU ZXR 750 forks. Anyone else tried ZXR 750 USD forks on a KR?
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Post by corky »

the zxr750sp ones look great but are designed for a @190kg bike !!
then what diameter are they?
would you have to use zxr750 yokes?
what length are they?
what is the wheel spindle size?
what is the distance between centres of the brake mounts?
would you have to use the zxr750 wheel/discs?
gonna ask some Q,s to the seller...
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Post by the-elf »

Talking of ZXR750 USD forks there's a pair of ZXR750 RR SP forks on evil bay ATM. Item number: 320182262309 Ummmm fully adjustable =P~


edit /me must be getting a bit slow on the Ebay searches LOL beaten to it by a mile. :lol: :lol: :lol: :lol:
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Post by Red Devil 777 »

corky wrote:the zxr750sp ones look great but are designed for a @190kg bike !!
then what diameter are they?
would you have to use zxr750 yokes?
what length are they?
what is the wheel spindle size?
what is the distance between centres of the brake mounts?
would you have to use the zxr750 wheel/discs?
gonna ask some Q,s to the seller...

Oh, friggin 'ell, we just sort out how to do the 400 front end in and now we're off on the zxr750 :mrgreen: :mrgreen: :mrgreen:

Does the zx7r share forks with the zxr750? :mrgreen:
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Post by nate »

ummm... ok probably a stupid question but... ](*,) ](*,) ](*,)

What is the difference in diameter between the KR1-S forks and the ZXR 400 or ZXR 750 forks...

Is it not easier to just mill out the yoke internals to fit the forks? Or is there not enough meat on the yokes???

cheers

Nate
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Post by the-elf »

Red Devil 777 wrote:
Oh, friggin 'ell, we just sort out how to do the 400 front end in and now we're off on the zxr750 :mrgreen: :mrgreen: :mrgreen:

Does the zx7r share forks with the zxr750? :mrgreen:
ZX7R had one of the best front ends ever :D Umm these a thought =P~ :idea:
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Post by the-elf »

nate wrote:ummm... ok probably a stupid question but... ](*,) ](*,) ](*,)

What is the difference in diameter between the KR1-S forks and the ZXR 400 or ZXR 750 forks...

Is it not easier to just mill out the yoke internals to fit the forks? Or is there not enough meat on the yokes???

cheers

Nate
You need to use the ZXR400 yokes to fit the forks in a KR. You just swap the ZXR stem with the KR one. We're just comtemplating using the 750 one's insead as they are supposed to be a better design. Then again, there isn't a single original compoment inside of my ZXr400 forks :D
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Post by corky »

"Then again, there isn't a single original compoment inside of my ZXr400 forks"

yes but were they £99?

did you find that card for the tank decals (or is it your little secret?)
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Post by the-elf »

corky wrote:"Then again, there isn't a single original compoment inside of my ZXr400 forks"

yes but were they £99?
:lol: :lol: Err nope, but I did get them "buy one get one free" :lol. My mate only charge me half price for the one -off kit, springs seals and oil. If i had to pay the full price I might as well have brought a new set of gas adjustable Ohlins 250 GP forks. :-&
did you find that card for the tank decals (or is it your little secret?)
I am looking for it honestly O:) . Someone on here told me to use them, and their name was mentioned in atleast one or two threads. Plus now many motorcycle decal manufactures can there be near Long Eaton in Nottingham. Well they aren't in Long Eaton but they aren't far from there as I drove over in my lunch break from Ratcliffe Power Station to fetch them and I drove past there on route.
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Post by Red Devil 777 »

Was it these ?
http://www.the-image-works.co.uk/

Had some of them years ago.

Had a quick look on there, they've got KR250 decals shown.
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Post by the-elf »

:-$ don' t tell corky :lol: :lol: :lol:

Yep its them. I just spent five seconds using the search forum bit and found this.

"It was the image works where i got my from. Give them a ring on 01159443111 cost about 36-38 pound a set."

I just asked them to replace the normal S on the graphic with an R. You do have to prove that you have a CR gearbox and 35mm carbs though :lol: :lol: :lol: :lol:

Only joking corky :D
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Post by mgtkr1 »

elf, your right in thinking that kaze bike has 750 zxr forks but unfortunatly there the early r/way up forks. they ap[pear to offer more adjustment though and by the look of it the top yoke appears to be a std kr1s. p[robably the best forks to have without goiing down the usdown route when setup for a riders weight. especially if the std yokes can be used with the only one off bit been the spacers? if a complete 750 front end is used with kr yokes and possibly calipers(look very similar, same maybe?) then it could be a swap worth looking into for those who havent yet got the much better than std 400 usd forks. gonna scan ebay and see how much the r/way up forks off the 750 are availible
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