zx7r front end Mod.

Before i start, no i'm not just gonna buy a newer bike.
My new project, the last ever 7r i will own is taking shape. It looks like all that will be 7r is the body work and frame.
I want run lighter wheels (10r rear, 6r front) and radial calipers. 7r's run 43mm forks stock but these ones are bent. I'd like to run 10r forks ideally, but have got hold of (pretty much stole) a set of '07 6r forks. However 6's run 41mm forks.

What are the pros and cons? Should i use 41mm triples with the 6r forks? or should i keep hunting for affordable 10r units?
I'm thinking rigidity vs weight vs strength vs cool factor. Thoughts?

oh, and before someone tells me to grow up, i haven't actually. I just go where i don't get caught

i think the 6r forks will be stronger than stock, but any forks like that you get, make sure you get them sprung right, as they wont hold the weight of a 7 the same as they do a 6 or 10.

why not gixxer forks? easier to come by...

I hear what you're saying wattie and i agree regarding the springs. By my estimates weight will be well down on stock as i have alum tank, single seat with glass rr tail and a 10r engine. Engine itself is lighter and smaller as well as lack of carbs. And i will only ever be one up one this bike. In reality it is more a 10 in 7 frame and fairings than anything. But will get dry weight and go from there. I was more concerned about the strenghth of the staunchens and feed back of slightly smaller diameter.

Oh, and Why not gixxer forks? Coz they're not kwaka. Oh, and these were almost free. For some , bike manufactures are like a footy team

thanks mate

I could be wrong but I think the 10R forks are 41mm too. Not sure if they are any stronger, but I know either will be lighter than the stock 7R forks. I am really interested in how you are going to get the 10R motor in the 7R frame? From what everyone out there has said, it will take major modifications. If you suceed, please let us know how you did it. I am doing the 9R swap this winter. It's bored to 950 so close to a liter bike in displacement. When funds permit and I find someone knowledgable enough to do it, I am going to have the head redone, crank, flywheel, etc, machined lighter and balanced, then attempt to fuel inject it. The goal is to exceed 150RWHP at a minimum. If your going to swap the fork and wheels, you should consider the rear swingarm as well. I hear the 10R is a easy weight saving swap that goes well with the 10R wheel your planning on running. Good luck.

Just out of interest...does the 6r fork have the same travel and length dimensions as the 7? (except for the o.d.)

Just by the way, diameter isn't all...I would be following the load path...although the diameter is smaller sometimes the load can be spread over a greater area by longer thrust bearings in the fork itself or be made out of a higher quality material with much higher structural stress.

Both good points guys. The 10's run 43 so would most like slip straight into original triples with a bit of fiddling to get length right. i have two other stock 7's here to help with that. I agree Tack, about the size. All i do know is that for it's time the 7 front end was so far ahead of anything else japanese out there. I have never had any of the newer forks apart so can't comment on whats what. Thats why i'm asking.

To my way of thinking the 7 is the best looking kwaka ever, and punches well above it's weight. But inevitably it struggles against the big HP and nimbleness of current bikes. So I'm taking a different rout and spending coin on a modern injected and basically stock reliable engine rather than stretching a carbed 7 or 9 to with in inch of it's life. Just to be differentas much as anything.

Yes, fiting 10 motor is a big call. Physically it is narrower so it will fit between the rails. Will have to mill up some blocks to sort out mounting points and that is the biggest nightmare. The engine is also taller so there will be air box issues except I'm build moy own custom carbon unit using a K&N filter. Then there the massive fuel pump etc etc...

But as I've learnt from the family, you can fit anything into anything if you try harder enough or for long enough. Our last project below is a case in point.

Keep the chat coming guys. Very appreciated.

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I'm not gonna read it all so I don't know where you're up to exactly, but I'll have a spare top 08 zx6r triple clamp if you're after one.

Mate I can't wait to see your bike when it's finished, your plans sound awesome.

The guy that did my suspension (SOS at penrith) when he discovered the crack in the 10's forks made the comment that all later model forks these days are pretty weak compared to bikes of 10 years ago. I guess this is as they've shaved weight etc from the bikes. That being the case you might be better with ZX10 forks, if they are a different thickness tube, they probably aren't though. And if the ones you've got were freebies almost then it's probably worth a go

Sounds like it's going to be pretty trick when you're done.

..............

oh, and before someone tells me to grow up, i haven't actually. I just go where i don't get caught

I see nothings changed...has it Matt?

Ha ha Ian, no it hasn't. It's all about perception

How are you goin, New to this forum but coincidently am building a zxr750 with a zx9 b motor and a 950cc cap increase. Also have a pair of zx6r forks from an 05 model that I was going to put in my ZXR400 SP. The forks go straight into the ZXR750 lower tripple clamp but are tappered down at the top so don't fit the top clamp. If you put a zxr400 top clamp on it fits perfect. Next trick is to get some 300mm discs to replace these 320's. Any way I had the same concerns about fork stiffness and strength as you, the jury is still out and I am still unsure. However I did think the 6 and 10 were pretty similar in fork setup. Anyway I hope the zxr400 top clamp trick helps you out and I look forward to any of your Ideas. cheers


regards TK400

Nice info tk400.

Coincidentally, I'm looking for fork upgrade options myself for my L model. Can I ask which year ZXR you have?

No worries hope it helps. As for the year my 7 is a 95 model. i actually did wan't to stick with stock gear and put some better cartidges in because I can't imagine the zx-6 will have the same rigid feel of the old 7 front end. But with the cost of recroming for fork tubes now days, I gave that Idea a miss. What do you think about the front end ridgidity of the zxr750 with the 6 front end?....I sauppose I will find out soon, just hope its not a downgrade. I do like the Radial calipers but...cheers

Regards TK400

2003 6R fork are way better than 2005 in terms of quality of materials used, service life and tuning potential..

2007/8 6R fork are only good for re-springing sadly, they have a a non-rebuildable cartridge, so no other mods can be done. Other than chucking out the guts and replacing the whole caboodle... Naturally anything is possible if someone has the time and money; so at minimum you would phrase them as economically nonviable.

1st gen. R1's used 41mm KYB's BTW; but they also had a stricter dietitian @ Yamaha toward the end of the 90's! LOL