Author Topic: FZS600 USD fork conversion query (Read 12079 times)

Steve · « **on:** 15 February 2015, 08:39:04 am »

Hi all,

I've been tinkering with the bike for some time now and thanks to happy happen-chance I've come across a pair of 5PW forks. However, one small bump in the road is getting a hold of a top yoke to match- the 5PW having been produced for only 18-something months, they’re about as rare as hen's teeth.

To that extent, does anyone know if either of the earlier YZF R1 yokes might match the 5PW's? I can't see a reason why not if the 5JJ's forks are externally identical to the 5PW's.

It goes without saying any advice on the matter would be greatly appreciated.

Cheers,
Steve

Deefer666 · « **Reply #1 on:** 15 February 2015, 10:12:16 am »

I put an early R1 front end on my old FZS, you need the stem pressed out of the FZS bottom yoke and pressed into the R1 bottom yoke and the whole lot will slide straight in with the addition of a spacer under the top yoke as the R1 top yoke if thinner than the FZS one.

kebab19 · « **Reply #2 on:** 15 February 2015, 02:05:25 pm »

The offset of the 5PW yokes differ from the 4XV/5JJ, but as the 5PW forks are the same upper diameter as 4XV/5JJ you could just use them instead. They differ at the bottom, where they are 43mm diameter instead of the 41mm diameter of the first two models.

You'll need to basically follow Falcon 269's guide below, and I've recently discovered that the Fazer 600 and 1000's steering stems are identical:

http://fazer1000.yuku.com/topic/3408/R1-Fork-Conversion-Guide#.VOCl5iyM69c

Ruby Racing · « **Reply #3 on:** 15 February 2015, 06:18:41 pm »

Don't forget the R1 forks are shorter than the Fazer ones and so you will change the bike steering geometry. Ground clearance will also probably be reduced. You may need to get the forks re sprung and re valved.

Steve · « **Reply #4 on:** 16 February 2015, 06:50:27 pm »

Cheers Kebab and RubyRacing; variation in ground (and radiator ) clearance between my current and proposed forks was anticipated, but I didn't consider it to pose too much of an issue- I'll have a look into this but I won't know for sure until everythings fitted. It goes without saying that the last thing I would want would be my front tyre and radiator 'hugging' it out

Will keep everyone posted should anyone else be doing a similar conversion

I take it that if the 5JJ and 5PW forks are externally identical, then fitting a 5JJ front fender to the 5PW forks also shouldn't be an problem??

Deefer666 · « **Reply #5 on:** 17 February 2015, 08:40:13 am »

If you can find them a set of FZR1000 RU forks are longer than the R1 forks

kebab19 · « **Reply #6 on:** 17 February 2015, 06:31:39 pm »

Bear in mind that the 4XV forks are the same length as FZS600 ones (and early R6 forks). Although the 5WP forks are slightly shorter (check 1st picture of the R1 fork conversion link above) they're only about 5mm shorter than 4XVs, so I suspect ground clearance won't be dangerous.

There is however the small matter of the deeper bottom yoke, which strikes against either side of the radiator before it hits the lock stops.
And of course the bottom yoke lockstops are almost certainly not where they need to be.... any good at alloy welding?

Ruby Racing · « **Reply #7 on:** 17 February 2015, 06:42:44 pm »

Quote from: kebab19 on 17 February 2015, 06:31:39 pm

There is however the small matter of the deeper bottom yoke, which strikes against either side of the radiator before it hits the lock stops.

Got the same issue on my project Fazer with KTM Super Duke yokes. I think the cause is more likely to be that the offset (pretty sure it's called the offset) on the donor yokes is not as much as on the Fazer yokes. So the forks actually sit closer to the frame/radiator and the trail is reduced. Another reason why I highlighted the possible (negative) effects on handling/stability. I'm designing in the mount of a steering damper on my build for this reason. I may end up getting custom yokes made to replicate the offset of the Fazer yokes.

kebab19 · « **Reply #8 on:** 18 February 2015, 01:38:21 pm »

For my recent R6 front-end conversion, I just drilled my FZS1000 yoke's lock stops and mounted a nut 'n' small bolt through each.
It has reduced steering lock slightly, but at least the lock stops are now contacted before the radiator

Steve · « **Reply #9 on:** 21 February 2015, 09:06:34 am »

It looks like just about everything has been ticked off the old shopping list. My forks arrived a couple of days ago and besides a bit of weeping from the seals (but no pitting within the travel.... Phew...) they're perfect

. That said I couldn't believe how much shorter they are than the 5JJ's! However said fork length shouldn't be a problem once they're fitted to the wheel (will be using the original FZS600 wheel), and I will be using bespoke under-yoke-clip-on’s to avoid any fouling against the tank, also meaning I should be able to use all of my current handlebar switchgears, throttle tubes, levers, etc. May opt for some larger bar ends pending how much vibration I get off the clip ons. Hopefully very little- this is only a FZS600 after all. Possibly heated grips also, we’ll see.

Having spent the last week milling over old microfiche I've come to the conclusion (and feel free to challenge me on this; I'm not 100%) that whilst any of the 2003-2010 mudguards will be compatible with the 5PW forks, any of the R1 yokes should be compatible to one extent or another. Sadly there is variation between 4XV/5JJ and 5PW mudguards, and without them in front of me I can't tell whether said variation is purely aesthetic or whether the position of the mounting bolts has actually changed. Fork diameter didn't change until much later, so it looks like the 4XV, 5JJ, 5VY and 4C8 yokes are all compatible with the 5PW forks- the only change being position of the pinch bolts for some reason; it looks like the more recent R1's move the pinch bolts closer to rider position, and exaggerate that funny contour on the top yokes that engineers just go mad for. For that reason, I'm looking for a top yoke as close to the year of my forks as possible. It goes without saying, ideally the same year

It may be that some of the more recent top yokes are thicker than the earlier models, so I'm intending to see a couple of local bike breakers to measure up these yokes and see for certain.

Also for anyone interested, I've been in touch with a few suspension specialists regarding the R1 fork springs, and the only one to give me a clear definitive answer is K-Tech. Apparently the original 8.5N fork springs installed in the '03 Yamaha R1 forks will be fine for the FZs600 conversion. My local Yamaha franchise dealer confirmed this. Evidently the 30-something-kg difference in wet weight is negligible, but I am taking this with a pinch of salt- race techs tending to fall on the stiffer side of the spring spectrum than what I'd typically want for road use.

So forks, spindle, spacers, speedo, steering stem, headstock bearings, adjuster and lock nut, front wheel, brakes, instruments, another complete Fazer lock set... all check. Besides the shroud for the steering stem/ top yoke, the top yoke itself, clip ons, bar ends and the front fender am I forgetting anything?

Also any opinions on changing brake lines, etc whilst the project is underway??

Steve · « **Reply #10 on:** 21 February 2015, 10:53:19 am »

* Confirmed by eBay shop, 4XV and 5JJ mudguard unfortunately won't fit 5PW forks.

kebab19 · « **Reply #11 on:** 21 February 2015, 12:19:49 pm »

Would later 5VY Yokes not do the job? Plenty available out there & offset halfway between 4XV and 5PW

http://www.r1-forum.com/forums/archive/index.php/t-189634.html

Ebay # 321673370843

Steve · « **Reply #12 on:** 22 February 2015, 10:46:13 am »

Top yoke sorted

like Kebab said it looks like the 5VY will do the job

Steve · « **Reply #13 on:** 18 April 2015, 01:41:50 pm »

Hi All,

It's been a while since I've posted anything about the R1 front end up swap so I thought I'd share the updates.

I offered up the new R1 5PW bottom yoke (with FZS steering stem) and 5VY top yoke to my frame and it fits like a glove. A shroud was needed to reduce free play between the steering stem and bore, and to raise the top yoke up about 8mm as the R1 top yoke is quite a bit thinner than that of the FZS yoke. I think I will need to drill and fit grub screws into the steering stops to prevent any knocking against the radiator or clocks- the clearance between these parts is pretty close to say the least, as both yokes are much wider than the FZS's, but otherwise job's a good 'un

The next stage will be fitting my original FZS ignition barrel to the 5VY top yoke, the reason being to keep all the lock sets matching.

The OEM spec ignition barrel for the R1 is significantly wider than that of the FZS, and for the lock stop to mate with the frame during assembly I will have to lower the ignition barrel by quite some way also- 22mm to be exact. Some small hollow spacers should do the job quite nicely, and the mounting points for the ignition barrel will have to be enlarged and re-tapped for the new security bolts to fit during final assembly, otherwise the lock set simply won't be secure. I'll upload some photos during fabrication to better illustrate what I mean.

Once this is all done I will need to fit bar ends to my new Convertibar clip on risers. As I'm intending to use clip on's rather than the typical clamp riser conversion normally carried out on similar conversions, this should raise handlebar height to just 5mm lower than normal bar height on an OEM FZS front end. Bearing in mind I'm only about 5ft 4- a tad on the 'vertically challenged' side, this should suit me to a T. Furthermote there shouldn't be any hose/ cable stretch issues with the handlebars being more or less in their originally intended position. Weirdly enough the original FZS bar ends fit pretty well in the Convertibar handlebar ends- a happy coincidence although the Convertibar handlebars are intended for push-fit bar ends?! Some rubber tubing should ensure sufficient fitment and eliminate any free play. Alternatively PTFE tape and 'hope' should work as a short-term fix.

For anyone looking for similar clip on risers, I've had a look at similar companies- Renthal and Woodcraft both coming highly recommended- but all of the above charge extortionate prices for new bars. My advice, either have some 'bespoke' clip on risers made up or watch eBay like a hawk like I did. Needless to say I owe eBay and my local bike breakers a fair bit after all these parts.

Cheers again for all your advice and let me know what you think. I'll try to comment on this thread a little more regularly than I have been and hopefully I'll have some photos ready for you all the next time I update it

Chris · « **Reply #14 on:** 18 April 2015, 03:55:02 pm »

Be good to see some pics of the project.

Chris

jaywas · « **Reply #15 on:** 18 June 2015, 11:40:37 pm »

Hi Guys, took a different route when I fitted the R1 front end, had some custom yolks made which keep the ride height the same for shorter forks.
You will need to have the internals re-valved and possibly softer springs as well - mine rode like an absolute pig until I let Maxton loose on them.
I'll try to post some pics.

kebab19 · « **Reply #16 on:** 19 June 2015, 08:44:34 am »

Very very nice job.
Prefer the black anodised stanchions - more subtle than the usual gold versions.
Are those straight bars comfortable?

What's that - a standard rear brake caliper? Go & sit in the naughty corner

anutz · « **Reply #17 on:** 19 June 2015, 02:29:45 pm »

wow thats nice work - can someone tell me....why do you re-valve forks - is it just due to wear and tear or can valving be an adjustable part?

jaywas · « **Reply #18 on:** 19 June 2015, 07:40:56 pm »

The straight bars were reasonably comfortable but they have been changed now for Renthal superlows.

In answer to the revalving question most manufacturer settups are a 'that'll do' affair, people like Maxton can the fine tune them so they operate more smoothly. In the case of mine it was horrendous with the standard R1 internals but after they were 'tweeked' it is now pretty damn good.

Ruby Racing · « **Reply #19 on:** 20 June 2015, 12:48:22 am »

Quote from: anutz on 19 June 2015, 02:29:45 pm

wow thats nice work - can someone tell me....why do you re-valve forks - is it just due to wear and tear or can valving be an adjustable part?

A sports bike carries more weight over the front wheel so needs a firmer set up. Plus it's designed for control at speeds in excess of what a Fazer can achieve. Also the weight of the rider is relevant.

Then you have to consider the preferences of the rider. Bike web forums are full of "ideal" suspension settings for a particular model. There is no such thing. Only an ideal set up for each rider, as we all have a different idea of what is ideal. If Pedrosa got on Marquez's bike, or vice versa, they'd probably hate the set up.

Nebuchernezzer · « **Reply #20 on:** 23 June 2015, 11:01:02 pm »

Not adding anything to the conversation but that's a very nice Fazer

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