OK All....

I'm tired of the old... "it looks like it will fit" crap... so here it goes, I'm gonna take a step to try and clarify a few things on some of these swingarms everyone is so excited about bolting up (including myself). The big questions are always length and pivot bolt sizes/widths... so I've taken a few measurements off items that I currently have in my pile of parts.

If you have a swingarm that you can measure up and post... (RC51/VFR 02-later/etc) we'd all appriciate it... but please, NO EYEBALL measurements... I can guarantee eyeballs are off 15-25mm almost every time, if you need glasses, even more. Please use a caliper, if you don't have one and use a ruler... please mention that so people understand the level of accuracy... thanks...

*** My Disclaimer- These measurements were made using a large veneer caliper... ie. NOT DIGITAL... so that means I can pretty much guarantee that my numbers aren't 100% dead nuts on.... BUT they should be within 1mm or so, which for purposes of this thread is all I'm trying to provide you with. These numbers will give you an idea of the amount of work needed to make it work for your bike.

Method of measurement...

I measured swingarm length from the centerline of the pivot bolt to the centerline of the rear axle pushed all the way forward until it could not move forward any further. This was done without the adjusters which may/may not allow the wheel to go that far forward. I felt this dimension was most critical, as no matter what, this is the minimum wheel base dimension you can obtain and should give a good idea of wheelbase changes.

I measured swingarm pivot width from edge to edge of the inside swingarm surfaces NOT measuring any sleeves/spacers. Literally just the inner dimension of the cast swingarm.

Rear wheel opening width is measured from the inside of the swingarm where the rear axle passes through.

VTR SUPERHAWK -
Swingarm Length - 486.5 mm (19.15")
Swingarm Pivot Width - 165mm (6.495")
Rear wheel opening - 249mm (9.80")

CBR 954 RR
Swingarm Length - 532.25 mm (20.95")
Swingarm Pivot Width - 180mm (7.08")
Rear wheel opening - 249mm (9.80")

VFR 800 (1998-2001)
Swingarm Length - 515.5 mm (20.30") *** This measurement is with the rear hub adjusted forward... I'm not positive it's 100% as far forward as it can go, but it's about as close as I felt comfortable moving it.
Swingarm Pivot Width - 165mm (6.495")


Other notes...
The rear axle on the VTR is 20mm dia. the CBR 954 is 25mm dia.
Both the VTR and 954 have 25mm of adjustment from wheel full forward to full back.
The pivot bolt diameter for the VTR and VFR is the same. The CBR is considerably larger... I forgot to write it down... sorry.

Well... that's all I got. I hope this is somewhat helpful and guys out there with other parts can do the same.

J.

 

Thanks for starting this thread, I think it will be a big help for those people who aren't familiar with the details of such a modification. Anytime you do something like this you will have to deal with some sort of fabrication. It's nice to know the particular differences up front as to better plan for this work.

 

I'll just add my thanks... This should have been done long ago...

I'll get the calipers out and get the 929 dimensions in a few days time, but they should be as close as no difference to the 954 since that swap has been made by several 929 owners...

Could we modify to include inside & outside on the pivot bolt width? The reason being that the outside width does indeed make a huge difference on the ability to mount as well...

 

Thank you for taking the time to do this! Avery good idea and should be really useful

Only a suggestion, but perhaps the overall height of the different types of forks that are most commonly used for the Superhawk conversions could also be included (measurement taken from the wheel spindle centre to top of fork leg with no load) along with the measurements from the standard forks?

Chris.

 

BTW looking at the service manual tells me that the VTR swingarm pivot bolt is 20 mm and the CBR 929/954 is 25 mm...

 

Thanks all.... I figured it was time for something like this.

Tweety... I'll take some outside dims in the next day or so.

Yeah.. we should start a fork measurement thread as well... but I'm sure alot of that info is out there, you just gotta dig for awhile.

I'd really like to know the RC51 SP1 and SP2 measurements.... I knwo the SP1 arm in about .4" shorter... might be the best of all worlds (short length and no exhaust mods) although the pivot bolt is larger in diameter than the Hawk from what I understand.

J.

 

i will get you the sp2 measurements tomorrow this time.
sp2 arm is lighter than sp1 also

 

Yeah... SP2 arm has a few benefits, only real negatives are the length and cost!!! LOL! The other big plus is it's damn beautiful... but I'm curious on the length, it will be great once you post up the dims.

J.

 

the nice thing would be if we can 'the optimum arm' and then have a batch of any custom parts that might need cut... then we can all bid against each other on the swingarm themselves.

tim

 

The SP2 is also a 20 mm swingarm bolt as the VTR, which is a big plus... The SP1 is a 25 mm bolt according to the service manual... Not that it's a big problem... a small tube should fix that... But the freaking crossbar in front of the header on the SP1 is a bad thing...

 

Yeah I know the SP1 bolt is larger... but I figure your messing with spacers for most any of these swaps, so that should be one of the "minor" items provided you can machine them, or have someone do it for you.

I did notice the crossbar... but was hoping that wouldn't really effect things. The one big issue is the shock/linkage mount... I've recall someone cutting it off and welding on the VTR mount (SP2 arm)... but I think you could also fab a set of custom linage plates that would allow for the VTR shock and the RC51 swingarm mount as is.

J.

 

for me the cleanest thing was to add the mount to the arm like i did.
that way all i needed were two flat plates for linkage.
i have some more ideas,when i get them worked out in a physical
form i will post them also.
ive done this much,may as well go all out!

 

Nuhawk please note changes

 

where did you get the swingarm measurements? i need the comparisons between the 954 & the 900rr

 

woody

due to the way the 900rr is constructed it will not fit.
what others have done is cut the brace off the 900
and weld to superhawk swingarm.

 

VTR SUPERHAWK (all years) SlowHAWK
Swingarm Length - 486.5 mm (19.15")
Swingarm Pivot Width - 165mm (6.495
Rear wheel opening - 249mm (9.80")
Swingarm Pivot Bolt - 20 mm/dia
Wheel Axle Bolt - 20 mm/dia


CBR 954 RR (2002-2003) SlowHAWK
Swingarm Length - 532.25 mm (20.95")
Swingarm Pivot Width - 180mm (7.08")
Rear wheel opening - 249mm (9.80")
Swingarm Pivot Bolt - 25 mm/dia
Wheel Axle Bolt - 25 mm/dia


VFR 800 (1998-2001) SlowHAWK
Swingarm Length - 515.5 mm (20.30")
Swingarm Pivot Width - 165mm (6.495")
Swingarm Pivot Bolt - 20 mm/dia


RC51 SP2 (2002-200?) hawkter996
swingarm minimum axle to pivot length-530mm
swingarm pivot width 180mm
Swingarm Pivot Bolt - 20 mm/dia
Wheel Axle Bolt - 25 mm/dia


CBR 929 (2000-2001) Tweety
Swingarm Length - 533 mm
Swingarm Pivot Width - 180 mm
Rear wheel opening - 249 mm
Swingarm Pivot Bolt - 25 mm/dia
Wheel Axle Bolt - 25 mm/dia

My measurements added in Italic...

Measured with an analog caliper...

 

Got some more... I don't think these are very relavant to the Hawk (ie. won't work with our bikes!!!)... but if you work on other bikes, I figured these may be helpful...


All these dims are from this site...
http://guukan.org/garage/swingarms.html

Honda VFR ('90-'2003+), Hawk, RC30/45, NSR250 all use the same relative rear wheel offset. i.e. mix and match wheels amongst the various models and so long as the spindle face is unmolested the wheels will remain centered.
90-93 VFR (shock linkage mount is two lobes on bottom of swingarm)(shock end is a 'fork')
Length: 565
Pivot width: 242 (+3.5 thrust collar)
Pivot diameter: 20
Eccentric outside diameter: 105
Eccentric width: 70 (+3 crenelated 'edge')
Caliper carrier diameter: 75
Caliper carrier width: 14
Brake rotor diameter: 255
Brake rotor mount diameter: 110
Sprocket mount diameter: 175
Wheel drive diameter: 100

94-97 VFR (shock linkage mount is one lobe on bottom of swingarm)(shock end is an 'eye')
Length: 560
Pivot width: 227 (+3.5 thrust collar)
Pivot diameter: 20
Eccentric outside diameter: 105
Eccentric width: 70 (+3 crenelated 'edge')
Caliper carrier diameter: 75
Caliper carrier width: 14
Brake rotor diameter: 255
Brake rotor mount diameter: 110
Sprocket mount diameter: 175
Wheel drive diameter: 100

Hawk (shock is direct-mounted to top of swingarm)(shock end is an 'eye')
Length: 545
Pivot width: 235
Pivot diameter (right): 15
Pivot diameter (left): <22
Eccentric outside diameter: 105
Eccentric width: 70 (+3 crenelated 'edge')
Caliper carrier diameter: 75
Caliper carrier width: 14
Brake rotor diameter: 240
Brake rotor mount diameter: 100
Sprocket mount diameter: 165
Wheel drive diameter: 100

RC30 (shock linkage mount is two lobes on bottom of swingarm)(shock end is a 'fork')
Length: 530
Pivot width: 235
Pivot diameter: 20
Eccentric outside diameter: 105
Eccentric width: 70 (+3 crenelated 'edge')
Caliper carrier diameter: 76
Caliper carrier width: 13
Brake rotor diameter: 220
Brake rotor mount diameter: 110
Sprocket mount diameter: 140
Wheel drive diameter: 85

RC45 (shock linkage mount is two lobes on bottom of swingarm)(shock end is a 'fork')
Length: 540
Pivot width: 250
Pivot diameter: 20
Eccentric outside diameter: 117
Eccentric width: 77 (+3 crenelated 'edge')
Caliper carrier diameter: 76
Caliper carrier width: 13
Brake rotor diameter: 220
Brake rotor mount diameter: 110
Sprocket mount diameter: 140
Wheel drive diameter: 85

RVF400 (shock linkage mount is two lobes on bottom of swingarm)(shock end is a 'fork')
Length: 540 (??)
Pivot width: 215
Pivot diameter: 20
Eccentric outside diameter: 105 (??)
Eccentric width: 60 (+3 crenelated 'edge')
Caliper carrier diameter: 76 (??)
Caliper carrier width: 15
Brake rotor diameter: 220
Brake rotor mount diameter: 110
Sprocket mount diameter: 140
Wheel drive diameter: 85

NSR250 / mc28
Wheel drive diameter: 85

MV Agusta F4 (shock linkage mount is bolt on, under swingarm. linkage arrangement is similar to Ducati 916)
Length: 545
Pivot width: 255
Pivot diameter: 20
Eccentric outside diameter: 105
Eccentric width: 76
Wheel drive diamter: 85

 

Here is what I've been looking at for the past year or so. A spare set of cases (I knew there was a reason I kept those around) and the 954 swingarm. Thanks to ? I have a spare VTR swingarm now so I can work out all of the details, or at least the majority of them, before I have to tear the bike apart. That's really helpful because if it takes too long the riding season will be here. It's hard to think of that when the current temperature is -2°F.



.

 

this is exactly why i went with the rc51 arm.

this setup just causes to many problem with shock and exhaust.

 

Hmm... The Mv swing looks like fun... But no... no... and definetly irreversably no...

 

Jamie... You will have to re-work either the headers to move the shock or the lower shock mount on the swingarm, as that doesn't line up with the stock shock position... I gave it up as to much work with the 929 swingarm... A SP1 swingarm is in transit to me now...

 

Well, I've had a lesser concern about the exhaust. Actually, I think I can keep the shock in the stock VTR location and therefore not have to touch the exhaust. I'm going to try and keep the custom parts limited to the suspension linkage. I still need to sharpen my pencil a little, and it's not going to be real easy, but I think it will be possible.

 

jamie

you gonna cut and weld the arm?


thats the only way i see to be able to use shocks stock location.

 

I agree with hawster996... I haven't physically measured the shock location on the 954 arm... but it seems almost identical to the VFR arm I have (even the linkage plates are close to identical)... Without a doubt you'll need to cut and weld the arm if you're moving the shock to the right, and I'd even say that you'll need to carve some of the arm away as the shock is quite a bit larger in diameter than the arm allows in the stock VTR placement.

 

Yeah, I'm concerned now that I might have to do that (cut the swingarm and/or modify the exhaust). In all honesty, I just eyeballed that and haven't really put much thought or measuring into it yet. You guys bring up good points, it looks like I have more work ahead of me than I thought.

 

It might actually be less work than you might think... The 929/954 is as much of center in shock poition as the VTR just the opposite direction... If the dogbone is flipped over everything but the shock lines up nicely... And mocking up the shock mount in the smaller hole in the VTR frame I concluded that there was enough room in the 929 swing... but that I needed to rework the header a lot...

This was the point where I gave up that approach and started with the RC51 SP1 swingarm... I'd like to keep the parts unchanged as much as possible... bolt on, bolt off...

 

Yeah, that's the road I was going down until....

You still need to have clearance for the rear exhaust pipe. For this you would need to notch the swingarm, or fabricate something different for the exhaust. Neither of those two options work for me (right now, at least) so that's why it's on the shelf until I can decide what to do.

 

Ok... The SP1 swingarm lines up nicely... So does the SP2... I have my own collection of swingarms...

One OEM VTR... One 929 that doesn't fit very well... One 954 (loaned) that fit's equally bad... One SP1 that needs new bearings in one pivot and a custom sleeve in the other to fit... (I have all the parts... )

And one SP2 swingarm that's halfway on... Need to figure out the lower linkage plates, and ride height... And a new chain... exhaust and shock position is unchanged and works...

I'll get pics in a few days when I'm in the garage next time (the bike and the workshop is at my parents house, as me and my father have stocked that place with tools)

 

Anyone know the weight of a stock superhawk swingarm? I am going to weigh mine now thats its braced and see how much weight I added.

I dont have a scale. I might go to the supermarket and weigh it with the produce scale

 

Stock swingarm 5.1Kg, SP1 = 7Kg, SP2 = 5,8Kg...