Kr1b fork conversion

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P1KL3
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Kr1b fork conversion

Post by P1KL3 » Tue Feb 26, 2019 12:58 am

Morning all.
Long time lurker first time poster here. In an effort to boost traffic to this wonderful corner of the internet I will start topics and (as soon as i have sorted photo bucket) I will start a rebuild project soon.

I have 2 kr1b 88 models. One I will set back to asnl near as possible factory (lucky i work for kawasaki hey) and the second I will work and throw a moto2 look fairing at it.

Tho I thought I'd start with a semi simple one. I have 2 kr1b complete bikes. I have one with s wheels and exhaust chambers. The forks on the s wheel set have the same top legs but the lover case has different mounting dimensions for the front calipers. Seems one set has the 6 pot caliper setup and one is the 4 pot that you see on the early zxr250 front brake setup. Which came on which?

Wondering if the forks were also different between the b and s models and wondering about A conversion...

In my part of the world (aus) zxr400 parts are hard to come by but I have a complete 92 zxr250 front end. Has anyone seen these on the kr1. I'd be able to skip the drama of front brakes as the same set is on the zx2r.

I will have many more questions but if any light can be shed on this area it will be greatly appreciated

Regards
P1KL3
09 zx10r since new +100000k on clock
93 zxr250c rebuilt for the lady
2x 88 kr1b resto (Why I'm here)
Hoonda rebel (couldn't sell my first bike)

dandan0162
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Re: Kr1b fork conversion

Post by dandan0162 » Wed Mar 06, 2019 12:37 am

Allright bud the Kr1s has the 4pot callipers same as zx4 callipers, alot of people do the zxr conversion but I never have but I think it's the 400 L model and requires a stem swap not sure of others but anything is possible just look through here some have done miricles lol
The Kr1 b model had the 2 pot callipers with different forks all together, i belive the six pots are just inserts in the Kr1s forks to change the diamiter of the bolt from 10 to 8mm(maby) cheers dan

P1KL3
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Re: Kr1b fork conversion

Post by P1KL3 » Wed Mar 06, 2019 4:17 am

Hey Dan,
Thanks for the reply. I was wrong in my initial post... One set is the tokiko 4 pot and the other is the nissin 4 pot found on the zxr250. Both fork legs I have have different mounting points and match each set respectively.

As for the fork conversion I will keep researching as the 400L set is as rare as teady bear poop...

I will keep looking. I'd post pics but can't figure out photobucket

Thanks Dan.
09 zx10r since new +100000k on clock
93 zxr250c rebuilt for the lady
2x 88 kr1b resto (Why I'm here)
Hoonda rebel (couldn't sell my first bike)

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JanBros
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Re: Kr1b fork conversion

Post by JanBros » Fri Mar 08, 2019 1:41 pm

do a search on 400 H and L forkes and yokes, ot's been explaind many many times.
My ultimate goal is to die young as late as possible !

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James P
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Re: Kr1b fork conversion

Post by James P » Sun Mar 10, 2019 11:23 am

Dylan,

The KR-1 has two-piston front calipers which are (to all intents and purposes) identical to those on the ZXR250. These calipers slide on their mountings to equalise the pressure of the pads on both sides of the disc. The ZXR250 uses larger diameter discs, but this shouldn't cause you any problem if you are fitting a complete ZXR250 front end. Although I can't point you in the direction of a specific example, the fitting of ZXR250 forks to a KR-1 is a known conversion - I just can't remember what has to be done with the steering column (a search of this forum may help...?).

As you already know, the KR-1S has four-piston calipers - these are 'fixed' (in that the caliper itself doesn't move). The KR-1S discs are of the same diameter as those on the ZXR250, although the disc offset may be slightly different.

The four-piston calipers of the KR-1S are arguably 'superior', but the KR-1 is a light bike and may not need better brakes if everything is in good order and you use suitable pads. You should find that all calipers from KR-1 and KR-1S models are Tokico brand.

Although the fork stanchions (inners) may look the same, they are shorter on the KR-1S. The sliders (outers) are different to suit the caliper mountings (and the KR-1S has a larger diameter axle). Some people have built forks using bits from each model, so the parts are interchangeable if you take the differences into account.

Front and rear wheels are the same for 1989 KR-1S and ZXR250. The wheel design was changed very slightly for 1990 models, but again the KR-1S and ZXR250 wheels are the same. As far as I know, 1989 wheels and 1990 wheels are interchangeable - the visual differences are very subtle and you'd have to know where to look to spot them.

There are some ZXR400s in Australia, but (as you point out) they are rare. However, you never know what parts may turn up from time to time!

Regards,
James

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steve@safetystep.com
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Re: Kr1b fork conversion

Post by steve@safetystep.com » Mon Dec 02, 2019 12:36 am

Hi James
An interesting post and you seem to have a real knowledge on the finer points of model changes.
Do you know if the first 'S' model, the 89/90 C1, came out with 3 spoke wheels?
I am looking to buy a C1 that seems to be 100% genuine in all respects other than it has 3 spoke wheels and not 5 spoke.
It has S front forks and brakes, S swingarm but 3 spoke wheel front and rear. It looks as though these were factory fitted.
I am aware that the B wheels don't fit the S forks and swingarm without some change work.
It has been a green and ebony bike and has black rims and black lower fork legs.
Steve

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JanBros
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Re: Kr1b fork conversion

Post by JanBros » Mon Dec 02, 2019 1:15 pm

no. no S with 3 spokes.
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James P
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Re: Kr1b fork conversion

Post by James P » Fri Dec 06, 2019 1:38 pm

steve@safetystep.com wrote:
Mon Dec 02, 2019 12:36 am
Hi James
An interesting post and you seem to have a real knowledge on the finer points of model changes.
Do you know if the first 'S' model, the 89/90 C1, came out with 3 spoke wheels?
I am looking to buy a C1 that seems to be 100% genuine in all respects other than it has 3 spoke wheels and not 5 spoke.
It has S front forks and brakes, S swingarm but 3 spoke wheel front and rear. It looks as though these were factory fitted.
I am aware that the B wheels don't fit the S forks and swingarm without some change work.
It has been a green and ebony bike and has black rims and black lower fork legs.
Steve
Steve,

As far as I know, Jan is correct in stating that no KR-1S models had 3-spoke wheels. From your description, the bike you are looking at seems to be a custom-built example (black 3-spoke wheels, black forks etc.).
You may like to check the chassis number to confirm the basic model and check the rest of the bike over to ensure it is what it is supposed to be (info on differences between KR-1 and KR-1S are listed somewhere on this forum, although it seems you have that aspect covered already).
It is possible to use 3-spoke KR-1 wheels on a KR-1S with suitable adaptors, so check the wheel sizes also (KR-1 3-spoke wheels are 2.75" front and 3.5" rear, while KR-1S 5-spoke wheels are 3" front and 4" rear). It could be that other 3-spoke wheels are compatible, so check the markings to try and ascertain what type they are.
Let us know what you discover!

Regards,
James

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JanBros
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Re: Kr1b fork conversion

Post by JanBros » Fri Dec 06, 2019 7:53 pm

normaly all Kawasaki wheels have a wheel code : F-xxx for front wheels, R-xxx for rear wheels

google the X-xxx codes and you'll find out what bike the wheels are from .
My ultimate goal is to die young as late as possible !

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