HOW-TO: YZF600R Swingarm Conversion Write-Up <Updated>

[mrfreeze5]

I've updated the writeup as much as possible after receiving some questions. Ive also uploaded all the pics in this writeup to the gallery and edited the posting so that in the eventuality that my photo hosting becomes unavailable(they really do suck) the thread is not worthless.




Since there isnt a stand alone write up on this, just the info hidden in the suspension sticky, here's my write-up for the swap based of what I did and learned during my swap. This should be a good resource for future conversions. Hopefully this can help take some of the guess work out of the process for those who are not sure if they can handle an upgrade like this. Ill also touch on related upgrades and swaps as they pertain to this conversion, but will not necessarily go into depth in the interest of specificity.

EDIT: Ok, somehow I missed the write up that ABS already did, but I still think this should be a valuable resource, It f'n better be, I spent a while on this thing...


Swapping a 96-07YZF600r Swingarm onto a 1989-1999 FZR600r and Options for Monoshock Upgrade
*Should also apply to FZR400 models


The Swingarms. Mine's bigger than yours

There are 2 different types of swingarms on FZR600s and there are lots of reasons to get rid of it. The 1989 and 1990 Years used a basic boxed steel swingarm. It is weak and ugly. For a bike with lots of power added or a wheelie happy stunter this can be very bad news. This swingarm weighs in at approx 11lbs(I may be wrong, I dont trust my scale anymore, but I will use my measurements for at least relative comparison)In 1991 Yamaha replaced the swingarm with the deltabox swingarm which weighs in at about 16lbs. It is stronger with more material and bracing and is more visually appealing, and the length from end to end is just slightly shorter than the 90 swingarm. The length difference between the deltabox FZR swingarm and the YZF600 swingarm is minimal and should not produce a very noticeable change in handling as a result except to maybe a very experienced rider as the wheelbase change is almost negligble. It also weighs in the same as the deltabox FZR swingarm at 16lbs bare.
The other major difference between the FZR and YZF swingarm is the pivot tube. The FZR is 8.75" between the frame rails. The YZF pivot tube is about 3/4" wider than that FZR, so it will not fit into the frame as is. You will need to cut down both ends of the pivot tube so that it will fit into the FZR frame, about 3/8" per side. I used a hose clamp as a template to make my mark around the tube and used a dremel to cut it off at close to the right size and then "fine tuned" the size with the grinder, just make sure both sides are equal. If youve got some energy and some time to kill, a hacksaw will work just fine. Once the pivot tube has been cut, the dust caps will not seat fully onto the tube. They will hit the weld on the swingarm. On mine, the interference was fairly obvious and I was avoiding grind the welds for clearance, so I lighlty touched the edge of the cap to the bench grinder and made a slight notch(maybe 1/8") and coupled with light grinding of the weld made for a nice fit. The distance from end to end on the YZF swingarm pivot bushing should be 8.470". This will allow the swingarm pivot bushing to fit inside the frame with seals and washers included installed on the pivot tube. You could probably use the FZR pivot bushing and not have to cut it since the pivot bolts are the same size, but I did not have one at the time of theis project.This is made from hardened steel and will not be easy to cut. I would recommend a band saw if available, dont use a grinder, they can be so imprecise and then you need a new bushing. The cut need to be perpendicular to avoid premature wear on the seals and bearings.
The pivot bearings inside the pivot tube are a press fit needle bearing that goes into the the outer portion of the tube that is bored out slightly lager that the rest of the ID of the tube, so that when they are pressed in they sit flush with the outer edge of the swingarm and wont press in farther. You will need to take a small grinding wheel on a dremel or air grinder and deepen this bore enough so that the bearings will sit flush. Be forewarned removing the existing pivot bearings can be very difficult and is nearly impossible to remove intact and reuseable, so have 2 new bearings ready for this swap. I took a small strip of 1/8" thick x1/4" steel plate. Cut it to the exact length and rounded the edges so that it sat on the edges of the bearing. This allowed me to use a solid punch in the center of the steel bar to force the bearings out. It still took some work though. By cutting off about 1/4" of each end of the pivot tube, the bearings no longer sit flush. To ensure you dont ruin your new bearings, you can take an old bearing that is still in good shape and go at it on a bench grinder for a bit to reduce the OD of the bearing so that you can slip it in and out to check the bore depth and not have to whack it back out. It may take a while, the bearing is made from hardened steel, which I hear is pretty tough stuff. In case you havent noticed yet, this entire conversion could be done in a day or weekend if you take your time using nothing but hand tools, torque wrench, dremel, hacksaw(optional if youre precise with a dremel. Youve got to be precise though!!), a drill and tap, and a little loctite. Im sure a case of beer wouldnt hurt either.
In addition to being stronger and slightly larger than the FZR's the YZF swingarm is wider, allowing for a wider wheel (5", which will not swap into the narrower FZR swingarm without major machine work) which brings us to the primary reason for doing this swap.


89-90 FZR600 Swingarm



91-99 FZR600 Swingarm



YZF600 Swingarm



Side-by-side comparison. The angle is a little off on this one, the YZF swinger and FZR swinger are very close in length, this pic makes it look much longer. The 89-90 swinger is the longest of the 3 by maybe 1/4".




And here's a comparison of the width differences between the YZF and FZR swingers




A little trick to getting the bearings out without trashing them is to make a driver. I dont have a blind bearing puller, so I went this route. This piece stays in my toolbox for the next time I need it. Drop it in the pivot tube and seat it against the backside of the bearing. Then use a piece of tube or a long drift to drive it out. I also keep the one bearing that I shaved down to be a slip fit. It comes in handy if you do this swap more than once. Ive done it twice and am about to do it for a third, so yeah, its handy for me.





The Wheel. Its all about the wheel.


The FZR600 comes stock with a 18" diameter wheel. 1989 models have a 3.5" wide wheel that fits a 140 tire, 90+ models have a 4" wheel that comfortably fits a 150 section tire. The problem is that there is a limited tire selection for 18" wheels in the FZR requires. So by swapping to a YZF swingarm, we can maintain close to stock wheelbase, while converting to a 17" YZF wheel with a 5" width that will fit a 160 section tire nicely. Many riders have used larger section width tires on these rims with varying results depending on brand and size, but that is another topic altogether and I wont discuss at this point. 160/60/17 is the stock tire size for the YZF wheel. One advantage of switching from the 18" rear wheel is that it lowers the rear end somewhat depending on what size tire you began with before the swap. This works out well for me since I have kinda short legs and I can flat foot the bike now comfortably, but then again, my bike had a taller rear tire than it should have to begin with, so it was pretty drastic for me, but most riders can expect about a 1/2"-3/4" drop. This can be addressed for taller riders with different dog bones to dial in their ride height.

150/60/18=25.09" OD
160/60/17=24.56" OD

The YZF wheel is a perfect match for the FZR wheel


The YZF forks and front wheel can be used very easily on the FZR if you want to upgrade from a 3" wide to 3.5" wide front wheel to run a 120 tire. But, thats another topic again.


The Brakes. Youve gotta stop some time


According to online microfiche, the part numbers for the calipers are the same for FZR600s and YZFs. The rotors have different part numbers, but they are the same diameter and thickness, and share the same mounting holes. The only difference is the cross drilling of the rotor. So you could conceiveably use a FZR caliper and rotor on the YZF wheel to save $$. I am still running my stock FZR caliper with the YZF swingarm with no issues.


Rotor Comparison: FZR on the left, YZF on the right



Here are a few pics of the assembled swingarm with a FZR caliper mounted:
(BTW, if dogs had thumbs, this swap would have been much easier...)






At this point in time, I decided to add spool mounts to the swingarm. Some steel rod, a basic lathe, a M6 tap, and basic welding skills made this a simple and worthy add.




Sprockets and Chains. What makes it go?


Stock gearing on a YZF600 is 47t in the rear. No need to upgrade to a different tooth count sprocket as most quick accelration sprocket kits for the FZR upgrade from the stock 45t rear sprocket to 47t and in some cases drop from 15t to 14t on the front sprocket for an even greater acceleration increase at the sacrifice of top speed. A 520 conversion is needed to make everything work without machining the sprocket hub. The YZF sprocket is offset about 8mm outside of the front sprocket. This wont do. It will destroy a chin with a quickness if it even moves. By offsetting the chain in the rear, you must match the location on the front sprocket. This can be done one of three ways.
The most involved and expensive is a YZF600 engine swap. It is mostly bolt in and will align the sprockets perfectly. The second is to machine the sprocket hub down to the appropriate width. I am not fond on this solution sinceit requires custom maching at great expense and time when there is an easier solution available. The solution I used was using a Vortex 520 front 14t sprocket for a Kawasaki ZX6rr with the stock FZR600 engine. The splines match perfectly to the FZR transmission utput shaft and offset the chain out 8mm. Perfect fit with no custom machine shop work. The only problem with this route is that you cannot keep the stock lock washer to keep the sprocket nut from loosening due to the offset of the sprocket. I drilled the transmission output shaft and tapped it for a bolt so that I could tighten it down with a washer underneath and loctite it in. I also used loctite on the sprocket nut, which is usually a good idea anyway. Use blue loctite, not the red, or you'll never get it back off for that next sprocket and chain change out. Another small issue with this sprocket is that it has a raised boss where the nut tightens down. It is approx 1mm tall. I ground this smooth on an bench grinder to allow more thread engagement with the nut. Stripping that nut would be a very bad idea. I also painted it afterwards. It wont help much, but the sprocket is gold zinc plated and where I ground down was bare steel. Luckliy the nut covers most of that area, and what isnt covered shouldnt get worn off IMMEDIATELY, but hey, who's sprocket nut isnt rusty?

Vortex Kawasaki 636 520 sprocket next to FZR600 520 sprocket



Kawi sprocket installed. Note ill fitting sprocket nut. This was before grinding down the boss on the sprocket. The safetly washer still won't fit though.




I no longer have the packaging for my front sprocket, so I don't have the PN, but according to the Vortex website, the Kawi 636 only has 520 pitch available and the part number is 3288 and is available in 14-16t configuration for the 2003-2006 636. This shot shows the side that mates to the transmission, this is not the raised boss that I ground down to clear the nut, its on the other side of the sprocket. Sorry, don't have a pic.





Here is the JT sprocket. A great option. First, it does not have the raised boss that the vortex sprocket does, so it doesnt need to be ground down for nut engagement. Also, the two threaded holes allow for a way to secure the nut. You can use two bolts safety wired together around the sprocket nut to help keep it from turning. This has been used quite successfully. In fact, I will likely be swapping to this one myself for more peace of mind.



Shocks


The rest of this conversion depends heavily on what shock you are going to use. I wont go into great detail on the shock swaps, we can save that for another write-up. The stock FZR shock will work and bolt up but is well known for being lacking in the performance dept. I believe that the stock YZF shock is far too long for the FZR and there is nowhere to mount the reservoir, but Im not certain on this fact sicne I never bothered messing with the stock YZF shock.The easiest way to upgrade the shock with this swingarm swap would be to use an aftermarket FZR replacement such as a Ohlins, Penske, or Fox if you can get your hands on one. Another popular and relatively easy swap is the FZ1 shock using a FZR spring. These are going to be your easiest swaps if you can find them and should offer great performance if set up properly. Some other brave souls have tried or are trying(waiting for solid answers) various other shocks including Busa shocks, kawis, etc. If youre clever enough, you can make anything work I suppose. One other popular shock to swap on the FZR is the 06 R6 shock. While this shock is a huge improvement over the stocker and is fully adjustable, the spring rate is much lower, and should have the spring replaced to a heavier one. The average rider trying to do this swap on their back porch do not have the skills or the resources to use this shock effectively with the YZF swingarm. It can be done, but due to the larger overall size of the YZF swingarm the reservoir hits the crossbrace. The only way to remedy this is to rotate the shock 180* to have the reservoir facing forward. This requires cutting, welding, and some basic fabrication. If you're a decent welder(or know one), have some steel, and some time, you can fab a new mount. You can either start from scratch or retrofit. If you retrofit the existing mount and rebrace it, you'll need bushings for the upper mount bolt(R6 uses a 12mm bolt, FZR uses 10mm, FZR mount is wider than the R6) that take up the difference. These have been made by several board members and may still be available or can be made in batch relatively inexpensive at a machine shop. I have many pictures, part numbers and measurments for this shock and this swingarm to work together, but I will not include it here since it is unlikely that most builders will go quite so far on a near bolt on conversion, just one pic for reference. If you would like more information on this swap feel free to message me or check the write up at the FZRArchives. So, overall, you're fastest, easiest method of dampening your rear suspension would be a shock already designed for the FZR, but if you're brave enough, come up with something original and share with the rest of us. The dogbones to connect the shock to the swingarm will vary depending on the shock used and rider height and preference. These can either be bought in stock length, lowering links with multiple heights, you can make your own out of 1/4" steel plate, have them custom made, or try different bike's links for a good fit.




ABS made a great post with oem lengths of shocks for different bikes in the Archives' suspension sticky. So if you are feeling adventurous or find one for dirt cheap on ebay and want to try it, here's a reference to start with.

OEM Shock Lengths-Thanks ABS!!

EDIT: Since my swap was done in 2007, the newest shock out there was a 07. But another board member has successfully used a 2008 R6 shock on their bike, flipped 180* without modification to the shock mount. It looks like the reservoir is lower and does not have the slanted top that interfered with my 07 shock. So if youre doing a YZF swingarm swap and want to use a R6 shock, try the 08. Looks like it would bolt right on like any other R6 shock swap. you would just need the spacer bushings and shorter dogbones! Here are some pics(with FZR400 swingarm on 600 frame)





Pics courtest of Hagalout



Rearsets and Peg Mounts


The rearset clearance topic has come up lately and is an important topic. The stock peg mounts will not clear the wider swingarm as they are. Some trimming will be required to clear the swingarm or aftermarket rearsets can be used. Personally I am running the rearsets made by China_Racer 1 and could not be happier. BUT, I cannot take full advantage of their adjustability.Due to clearance issues, I can only use 2 or 3 of the lowest and farthest forward settings, luckily this is a comfortable position for me. I also had to slighlty shave the master cylinder stud to clear as well. Its damn close, but there's enough space I think. Some users have tried Woodcraft rearsets with good results, but I am not sure if they clear out of the box as I have not laid hands on them personally. Many riders have had good results from trimming/grinding the stock mounts to clear. There appears to be sufficient material to do so and this is a very inexpensive fix. Be cautious if you are grinding them down though. The mounts are aluminum and aluminum can do a number on a bench grinder wheel by clogging it and making the process more difficult and less precise. A bandsaw/hacksaw/linear cutting device may be more effective depending on how you are set up.

More than likely, the bracket that holds the brake light switch will interfere with the new swingarm. This bracket needs to be cut off. To maintain use of the rear brake light is a simple fix now that the brake switch is gone. A hydraulic brake switch that replaces the banjo bolt at the master cylinder. It uses a simple 2 wire hookup and is less than $20 from the local dealership or online store. The banjo bolt thread pitch is 10mmx1.25. I used K&S PN 12-0010 and picked it up locally. I cut the stock plug off the old switch and soldered it on to the new switch, but standard bullet connectors from radio shack work too if you dont mind cutting the stock harness.


courtesy of:abs600fzrr

Here is pic of the right rearset before trimming the MC stud. It did not hit at its normal location, but as the lever was pressed, it would contact during its travel. This may not be an issue with the stock setup. You can also get an idea of the dogbone difference with my setup. Since I used the R6 shock(about 10mm shorter) and I am a shorter rider(5'8") I had to make a drastic change in length. These are not the final dogbones I used, only what I used for measurement and mock up.





In this pic is a FZR lowering dogbone ranging from stock size to a 1.5" drop and my template is even shorter. This can vary depending on rider height, weight, and shock choice, but it gives you an idea.






That covers everything I can think of at the moment regarding the YZF swingarm conversion. It is relatively simple with basic knowledge and the right tools. I would rate this swap as a 2.5 difficulty out of 5, 5 being engine overhaul, and 1 being oil change. I was able to finish this swap in about 8 hours total and that was trying to puzzle things out as I went. If I did it again, Im sure it would go much faster. I would strongly recommend while you are replacing your entire rear suspension to replace all your bearings and seals at the same time. Wheel bearings, pivot bearings, linkage bearings, wheel bearing seals, pivot bearing seals, etc. You already have the parts disassembled and you dont know what was done to that vehicle before it was parted out. Its peace of mind that you wont have to tear into your rear end again in a few weeks or months to start repairs already.


And finally, a finished shot with the YZF swingarm install. Looks like stock, like it was meant to be there.








And an exploded view of the whole assembly




1000 Mile Evaluation:

I LOVE it. The bike is so stable at all speeds, it feels 10x better than a stock FZR. I was concerned the lower spring rate on the R6 shock was going to be a problem. I know I knocked some weight off my bike, but Im not sure how much, so it probably helped a little. By using the longer FZR rear suspension knuckle on the YZF swingarm, the extra leverage seems to help and the shock feels perfect to me, and I weigh in over 200lbs with gear. In fact, the shock was perfect with the preload all the way down. So I am not going to bother respringing this shock for this setup. If I do this swingarm swap again on a FZR, which is very likely, I will use the later model R6 shock flipped like mine and save the trouble of remaking the shock mount. Another thing I need to address with this setup is the sprockets/chain. For no apparent reason, my chain seems to bind ever so slightly moving around the front sprocket. The chain also rides pretty strongly on the chain guide with the way the ride height is set. I am currently running 14/47 gearing and love it, but I am going to switch to 15/50 over the winter to hopefully take some stress of the front sprocket, and help clear the swingarm a little better and maybe reduce a little friction and wear. I am going to switch to the JT sprocket and do the safety wired locking bolts. I am just relying on loctite right now and it doesn’t give me the warm and fuzzies. Id also like to get a steel rear sprocket too. Otherwise, the swingarm has been great and the bike rides like a dream. I REALLY like the 160 tire on there and personally have no desire to step up to a 180 on the FZR. Ive thrown this thing around in the canyons a few times and have been very pleased with how nimble and responsive it is while still feeling extremely stable. Its very confidence inspiring. I am sure the R1 forks help this fact out too, but the combination is fantastic. And even though the YZF swingarm is slightly longer than the FZR, I still have a shorter wheelbase than a bone stock FZR.

[mrfreeze5]

As time allows Im going to work on a few more write ups to add with some tricks I learned and problems I encountered. It all depends on time which I dont have much of now

What year front sprocket did you use from the KAWA zx6rr? Did you have to space out any of the front pegs? Is 160 the largest you can go on the yzf swing arm?

Great write up. I keep going back and forth on between the 02R6, 04R6 and the YZF swap. I cant make up my mind

.

Off the top of my head I dont recall the year, but I can have the vortex part number posted tomorrow.

As for the pegs, good question, I forgot about this aspect. I am running China_Racer's rearsets that are super adjustable, but due to the wider swingarm, I cant use several of the lower settings for the pegs on the mounting plate. But this worked out fine for me since I have relatively short legs and am 5'8" and where they fit just happened to be where I wanted them.

Now if you are runnign stock rearsets, they will interfere with the sides of the swingarm. On the stockers, there is plenty of meat there at the end around the screw boss. You can grind it slightly back at an angle to clear the swingarm enough.

The 160 tire is the stock size that comes on that 5" wheel. It is very common among YZF riders to run 170s on the stock wheel, much like some FZR riders put a 160 on a stock wheel. Some people dont notice any ill effects, others hate it.

You can squeeze up to a 190 onto the YZF swingarm though. You can use a FZR1000 wheel which is 5.5" or 6", I honestly dont recall at the moment. It has the same axle diameter as the YZF. It probably requires some machining to fit the brakes and sprocket properly, but I know its been done on YZFs. To do this on a FZR you will more than likely have to have a YZF engine since the wider wheel will space the sprocket out more than a YZF spacing, and thats just too much to compensate for. You also cannot run the hugger with a 190 tire, it will contact.

The YZF forum will be a much better place for info on the 190 swap. Personally I see no need for that big of a tire on this bike and will likely hold at a 160.


If this is to be saved for future use, is there a way to permanently host the pics in the thread? My account is kinda lame and if I dont check in on it regularly pics can get deleted. Id hate for my possible inattention or lack of time in the future to take away from the resource.

[mrfreeze5]

Another factor of this swap for shorter riders is the change in tire diameter. The YZF600 wheel is 17" as opposed to the FZRs 18" and the overall diameter of the stock tire is different and can affect ride height.

A 150/60/18 Tire has an overall diameter of 25.09". The YZF 160/60/17 is 24.56". My bike had a 150/70/18(26.27") on it when I got it and was way too tall for me. Switching to the YZF rear end made it much more comfortable.

Another difference this can make is in acceleration. Decreasing the diameter of the tire without changing the gearing would add some accelleration and sacrifice some top speed, but when you combine that with the stock 47t gearing on the YZF wheel(if you decide to not regear to stock FZR specs) and even a lower front sprocket like I did, the bike should accelerate significantly faster than before, but again, at the sacrifice of top overall speed achieved, which doesnt really matter to me much. 0-120 is about all Ill use mine for.

[mrfreeze5]

Write-up updated with front sprocket info and more pics. All pics have been uploaded to the gallery as well and the post edited to link to the gallery instead of my hosting, which sucks. Ive been looking at the wiki, but have never used one, so I dont even know where to start to load this. Also, if you notice anything else that should be added or edited prior to wiki-dom, let me know.

[Lasse]

This should be a good resource for future conversions.
Hopefully this can help take some of the guess work out of the process for those who are not sure if they can handle an upgrade like this.

Is the 1991-1999 FZR-600 swing arm a direct bolt on, on a 1989-1990 FZR-600 ?

Also the 1990 FZR has only the tiny 3,5" rear rim !

[mrfreeze5]

yes, the 91-99 swingarm is a direct swap for the earlier one. '89 only had the 3.5" rear wheel. In '90 it went to a 4". But that swingarm came on the 89 and 90 models.

[PIMPMYFZR]

Made up my mind. Im doing the YZF swing arm swap since I have another bike to ride in the mean time.

What year is that front sprocket from that was used for spacing out?

Question.....On the install of the front sprocket could you safety wire it? Drill a hole and use some safety wire through the bolt and sprocket? That could help it from backing off I would think.

that doesnt actually sound like a bad idea but i dont know if it would work. this is the one i ordered
http://cgi.ebay.com/ebaymotors/03-04-05 ... .m14.l1318

but i could not get the sprocket nut to tighten with the recessed part facing in so its up to you which and where you get the sprocket from

[PIMPMYFZR]

swingarm , wheel , brake arm , front sprocket , rear sprocket , chain im using my old one though, but ..make sure u have the right spacers and collars i had to order 3 diff spacers and collars as they didnt come with my swingarm/wheel , make sure you measure from the center out . i did and still cut off alittle too much on one side , but some how it measure up to required mm need to fit , dont ask how .... ill find out once the wheel is bolted up and see if its centers though ... and of course rear tire as im sure you know , but pretty much thats all you need if your using the stock shock .. shock linkage used from the fzr pretty much just have to figure out what todo with the rear brake light sensor<i cut a slip in the bracket and pushed it out as far as i could so it doesnt touch the swingarm> and the rearsets will need to be grounded down or machined , im using 2 5/16 spacers to space everything out , but im not finished so dont quote me on it ... more info as i proceed ...the funny thing is i thought i would get this done in under $200 that was my goal for doing the whole project .. not for the yzf swingarm or for the bigger wheel just to see if i could get it done under that price , now im at almost $200 just ordering tedious parts like , spacers , collars , bearings , lil stuff like that .. i wanted to order a trick rotor like abs .. but i figured on a stock 14 yr old brake caliper why buy a new rotor .. so if you swapped out from r6 calipers maybe a yzf600 trick rotor would look nice back there , its a real easy swap out !!! i would be done but i didnt measure my fzr rear sprocket to the yzf rear sprocket so today im hoping my vortex 47 tooth sprcoket comes in . got it off yzf board member for $45 .
ive been wanting to do this swap since 2004 and it took me 3 1/2 years to gain the courage< and of course MR FREEZE beautiful write up>

[mrfreeze5]

I dont think the safety wire idea would work very well. For one, the nut is huge and has lots of extra material as well as the recess for the safety washer. It would be very difficult to make a stright hole all the way through. And do you know exactly where that nut will line up when you torque the nut down? Seems kinda sketchy to try and torque the nut and line it up with the hole. To do something like that, you would need a castle nut, but you need shaft sticking out of the nut to use a castle nut. And if that were the case, this discussion would be moot since you could just use the safety washer

I actually drilled a hole directly into the output shaft and tapped it for a bolt. I then flipped the nut(recess facing outward). I used some loctite on the nut, then threaded in and loctited a bolt with a large washer into the shaft to act as a lock bolt. Next time I have my sprocket cover off, Ill snap a pic.

[haro504]

what did you use to drill a hole into the output shaft, was it a hand drill or some other type and what size and depth

[PIMPMYFZR]

I'm probably gonna end up going this route Also for now I just have the sprocket nut turned around and just hoping it doesn't come undone!

[slayermd]

I havent really seen this anywhere, but Im guessing that the FZR axle cant be used? Also, I have a Honda F3 rim so I dont know if that would cause any problems with spacing.

Otherwise Im excited to do the swap. I just won an arm on eBay and Ill start gathering parts here soon to get the job done. Im in no hurry because the FZR is going to be my race bike for next summer.

[mszilves]

Hi guys, almost finished my swap so far, and here's a quick update and some things I've learned along the way, and of course, a couple of pics. I gotta say a big thanks to mrfreeze for all your work doing the write up, it was huge help, and a big time saver.

Ok, moving on, first things first, the finished product, I believe as freeze said, "like it was meant to be there":



I ended up using the JT brand sprocket for the front, which does not have the boss like the vortex one, so no modification will be required. This is the exact sprocket: http://www.bikebandit.com/product/A5261045 Part number: JT130715

This is what the sprocket looks like on, without the nut, just about a perfect fit. As mentioned, you won't be able to get the lock washer on, but I'll tell you how I solved that issue next.


And here is with the nut on. As you can see, with the nut flipped, it makes complete mating contact with the shaft threads, so I felt good about that.


Now as you can see on this last pic, the JT sprocket comes with 2 threaded holes in it. What I did first was use blue loctite on the threads, as well as the back of the sprocket nut. (One good thing about the nut flipped around is that the entire face of the nut is now in contact with the sprocket, and not just the rim. This is hard to describe, but you can see the "hollow" on the side facing out now.) What I'm going to do for extra peace of mind is loctite a small headless hex bolt into one of the threaded holes, which will stop the nut from rotating off in case the loctite loosens, I doubt that will happen, but better safe... I don't have a pic yet, but you can see in the last pic that if you were to put a bolt in the hole, it would stop the nut from spinning.

On to the suspension setup.

Since I recently put on a FOX TC, I of course kept that. One important thing I noticed was that with the YZF swinger, the dogbone pivot on the swingarm is slightly to the rear and down, as compared to the FZR. This will change the angle of the dogbones at the shock knuckle, and thereby change the shock ratio. I used the FZR knuckle and dogbones. The good thing is that if you are using a stock weight spring (730lb/in), this spring will now be plenty for most riders, and will stiffen up the rear noticeably. I had a 750lb/in Eibach on my FOX, which for my 185lbs with full gear is perfect! I have 12mm static sag, and 33mm rider sag, which is well close to what most expert suspension tuners recommend.

Also, because of the change of the swingarm pivot location, if you use the stock FZR knuckle/dogbones, the swap also lowers the rear by about 1/2" or so in addition to any small lowering that results from the tire diameter change. In total, expect the rear to drop by about 1/2 to 3/4" as freeze mentioned. I just used the height adjustability on my FOX TC to dial in the difference, but you can also experiment with the YZF knuckle and custom dogbones. But if you're on the shorter side, this will be a welcome drop anyways.

So that's about it so far. Took it for a 40km test ride yesterday, and the handling is definitely much improved, at least to my liking. The bike feels ALOT more stable standing up and riding in a straight line. In the turns, it does take a slight bit more force at the bars to initiate the turn, but the bike felt nice and neutral in the turn, and exited smoothly. So far, I really like it. And the slow speed jerking is also noticeably reduced with the 520 conversion, even though I kept the gearing stock 15/45. And of course, looks much better!

More to come...

[PIMPMYFZR]

Damn that looks nice ! Did you put a screw In the theaded hole ? Did you have any issues with the chain rubbing? As far as the rearsets did you have to space them or machine them? Looks very clean done!

[mszilves]

Damn that looks nice ! Did you put a screw In the theaded hole ? Did you have any issues with the chain rubbing? As far as the rearsets did you have to space them or machine them? Looks very clean done!

I did put a screw/headless bolt into the threaded hole, I'll get a pic up soon, but with that bolt, there is no way the nut can spin past it. I have no issues at all with the chain rubbing anywhere. The clearance to the left rearset lower mount nut is probably 2-3mm, and after a 40km test ride, no signs of wear/rub anywhere. Right now I have a few washers spacing out the rearsets, total probably 10mm or so, and for now no issues. I'll probably shave down the rear of the mounts in the future to get it a bit closer. I also bent out the heel guards a bit to match. Overall, it feels really good. I was going to go with aftermarket rearsets, but the stock ones are working well, so I'm not gonna bother.