www.zxrworld.co.uk

It's looking like my L2 forks are buggered so rather than replacing them with ZXR forks, I'm thinking of sticking in something with a bit more adjustment.
I've seen a bike somewhere that had ZX10R forks on it. I was wondering if any ZX6R forks would fit as they are surely sprung for the ZXR's weight (I'm pretty sure newer the ZX6Rs very similar in weight to the ZXR now.
My thinking in swapping the forks is that I'll then have larger radial calipers and more scope to upgrade if needed. However, although I think they share the same size front wheel, what about spindle diameter, yoke and disc mounting?
I don't want to mix wheels ZXR rear, ZX6R front etc, and don't really see the point in modding a ZX6R rear on.

Any suggestions?

I originally did it. Someone else tried it with the 400 wheel but IIRC gave up as it was too much work, wheel needed different bearings to use 6r spindle, discs needed to be spaced wider on the wheel, and calipers spaced out.

The ZX6r 2003/4 discs are smaller then the later zx6r discs, so don't mix forks and discs, unless you want to fit spacers to the earler forks for the larger diameter, later discs. Forks fit straight into 400L yokes but are 25mm longer, depending how far through the yokes you want your forks, you may need a 1mm sleeve to clamp the clip on too as the forks are waisted between the top and botom yoke.

That year front wheel is 3 spokes and looks almost identical to the ZXR so no need to worry about different wheel look front to back.

You'll also need to work out how to run the speedo, or fit an electronic one, unless it's a track bike of course.

Do a search for my posts, you may find all this and more detail with some pictures

P.S. ZX10r forks are wider, IIRC 54mm, at bottom yoke so will not go into 400L yokes

P.S. again, 6r springs are 8.5kg's, perfect for racing, standard 400L are 8kg's but progressive, so 6r should also be fine on the road

Excellent, thanks for that. I don't need to worry about a speedo as it's gong to be on my track bike.

Do you reckon it's worth it for the caliper upgrade? Or am I better off getting some ZXR400's resprung. I assumed the ZX6r's would have more adjustment to play with.

Actually, are you allowed to run different shocks/wheel in the BMCRC F400? I'm pretty sure it's just the swingarm and frame that have to be ZXR isn't it? I'm hoping to get my ACU and do some races next year. Would be a waste to practice on a ZX6r front end, and then have to go and buy and set up ZXR400 forks.

Thanks again

Just sent this to someone else, so to save me starting again I'll just copy it here:

Firstly bear in mind that most, if not all lap records at bemsee/mro were with standard forks and on treaded tyres, so the standard forks can be made to work very well obviously. I went down the ZX6r conversions route because my forks were crap and it would probably cost £300+ to get cartridges fitted and then get it all set up. I also needed to overhaul my calipers, parts alone were £80+, also needed 2 sets of discs(EBC £400).

So add all that up and it actually worked out cheaper to buy a second hand ZX6r front end. Forks £200, calipers £100, 2 front wheels with discs £400, plus axle/mudguard etc. Bear in ind that these were all only 3 years old at the time so almost new not requireing any overhauling. The bonus was the brakes are awesome, the forks were perfect once fresh oil and set up done, fully adjustable, discs far better than EBC, etc etc. also almost 2kgs lighter.

If you've already got good brakes, discs etc, then it would be cheaper just to get the 400 forks done.

Bemsee allow this conversion, but check with other clubs as they may not.

Hope that helps.

Cool ok, I'll keep an eye out for both forks. I'm not expecting to fit them and gain seconds in lap times, but my current forks are bent, calipers need a good service, and I want lighter discs so I figured I may as well 'upgrade' to something with more stopping power and adjustment.

Good point about the 2003 though. 6 years ago means they'll prob need a service so might end up costing a bit too much. Plus I'm pretty light so might be too stiff for me! lol

Anyway, thanks for your help. I'll let you know how I get on.

I'd look for a set of forks/wheel/brakes and slide them into the stock triples. That is the easiest way to do it. The wheels will swap you just need the correct discs, after 04 they are slightly larger in diameter. The 03/04 forks use a bracket for the front fender, 05 and later have it built into the lowers. I was never able to get my stock brakes to work as well as the ZX6r radial mounts. With a good pad it's one finger braking on the zx6r brakes.

I have a pair I am fitting up at the moment with a set of marvic wheels I am using the standard axle and reducing bushes in the axle clamp bores. also using alluminium spacers instead of steel. I had noted the the problem with the bar clamps and was still thinking about that part. Ballsouts Idea is probably the best. I am still tossing up as to a disc combo, I have a pair of brembo 320mm on the marvics but they are obviuosly overkill with radial calipers so I will be keeping an eye out for some good 250 gp ones ( I need 6 bolt brembo pattern ).
Ballsout have you tried any different oil combo's in these and if so do you have a recomendation. cheers

REgards TK400

is it the zx6r B1H B2H 2003/04 forks that fit in the zxr400L yokes?thanks,ian

the ones I have are 2005 model kayaba with 4 pad tokico's. As for the others I beleive all are the same Dia. and length but the brand varies. I am not sure about the latest ones with the inverted spring configuration. Someone else will know for sure about the earlier year for confirmation. Has anyone thought of trying the clipons above the triple clamps instead of below. was thinking this might be interesting on the road sought of a semi streetfighter combo...lol....cheers

regards TK400

tk400 wrote: Ballsout have you tried any different oil combo's in these and if so do you have a recomendation. cheers

REgards TK400

Sorry, I don't look in all the threads that often. I had mine professionaly serviced and set up, 5wt oil and IIRC 120mm air gap(edit: although we may have added another 10 or 20mm of oil to stop bottoming out, can't remember now, I'm a little over 10 stone), they were almost spot on first time out from base set up, just a few clicks here and there

Greville

ian rycroft wrote:is it the zx6r B1H B2H 2003/04 forks that fit in the zxr400L yokes?thanks,ian

Yes, that's what I've got, but the 'C' model forks also fit, the difference being the brackets for the calipers are longer to move calipers further away from axle to accomodate the larger discs