This is the first good excuse as to why this project is taking so long!



She's perfect!

 

The 954RR swingarm that I'm planning (if I ever get to it) will only add 25mm to the wheelbase. That's more than I would like, but it would put it right at the same wheelbase as the KTM RC8. I'm not sure what that means but it makes me feel better about it!

 

Well get your butt in gear then and try it... I need a roadmap to follow...

How are the odds of it working without extensive re-welding? Having the shock mount re-fitted, like hawxter996 did, I can deal with, but re-working the whole swing mount as someone did to get an SP2 swing to VTR stock lenght isn't an option for me...

I'll just entertain myself in the mean time by welding a 900RR brace to the stock swingarm...

 

No welding needed. Some spacers probably, but the work I've done so far shows that it's going to be pretty easy. The part that concerns me is the pivot bolt - the 954 uses wider pivot bearings so the bolt might not be long enough. It's not much, so hopefully that won't be necessary.

The hardest part is going to be the suspension linkage. I'm not expecting it to be horrible, but it will likely require some fabricated parts to work.

 

No welding?! Sign me up! I like mods that don't need welding... I have the tools and knowledge for machining (spelling?!) stuff but welding aluminium requires me to pay people... And I'm on a budget...

.
.
.
Are you done yet?
Sorry... couldn't help myself...

BTW since you have one around and have been measuring... Is the bolt for the pivot the same diameter? And what about the bottom link mount point? does that line up reasonably? (it probably does as you said no welding...)

What I see as possible problems, the lower link will need some parts fabricated, and some of the spacers to line it up... The pivot bolt dimensions, as you said lenght, but also diameter... The rear header?

The rear wheel... Probably won't be able to fit the VTR wheel... is the axle the same dimension? Oh well a 190 rear tire on a CBR wheel might be OK i guess...

 

Oh, never mind... I just bought a 929 swingarm on fleabay for £15... I was supposed to find a nice 900 swingarm to hack the brace of, but you gave me crazy ideas... And for that price I can afford to experiment...

BTW I'm blaming you guys for this... Oh well...

The significant other has announced that I'm officially not allowed to call it a firestorm/superhawk if I fit it, as it will then contain less original parts than swapped out parts... Go figure... I was pretty sure I passed that border long ago...

 

looks like you will have to move the upper shock mount.
is this true?
will you have to mod the header as in vfr mod?

 

Well this pics are way less sharp than I would have liked, but...

https://www.superhawkforum.com/galle...at//ppuser/397

https://www.superhawkforum.com/galle...at//ppuser/397

https://www.superhawkforum.com/galle...at//ppuser/397

From the looks of these the rear header is stock, or atleast very lightly modified, and the lower links are using what appears to a mix between stock VTR and 929 parts...

As Jamie said, what worries me is the pivot bolt, the one in these doesn't look like the VTR bolt, and the custom rearsets gives me reason to belive he needed that to fit the parts together...

But I'm willing to give it a try...

 

once you get your swingarm measure the width of the pivot area.
i will post rc51 measurement tonight.

 

if i remember correctly the rear wheel axle is same diameter,
and may be able to be used.

 

I don't think either of these will be necessary, certainly not the exhaust. From my rough measurements the upper mount should be ok. Bear in mind that I haven't actually started the process so I don't know what snags I'm going to run into yet.

Hawxter - do you have any more details than just those pictures?

 

Just tagging along.... curious to know if the rear cylinder header tube needs to be modded as well, as this is the sticking point in my VFR swap as well.

J.

 

jamie


which details do you need?

 

Rear wheel axle is confirmed to be the same diameter... Altough you can't use the VTR's... Needs the one matching the swing (929/954) as it also matches the chain adjusters (Another good reason for me to swap swingarm, the one's on the VTR are rather sloppy as new, and mine are worn... So I "manually" adjust...)

From the looks of the pics above the VTR rear wheel was used... It has the groove on the spokes... No CBR ever had that... So some fiddling with spacers and it should bolt up...

Also apart from the mounting arm the dimensions of the rear caliper is identical, so a new arm and the VTR caliper can be re-used... Actually the housing and and some other parts has the same Honda part no# so I suspect the caliper is identical... Same cylinder diameters also...

Altough it's unknown if the spacing to the disc is identical, might need shims there...

 

actually i was referring to its possible use as a swingarm pivot if original was to short for use on 929 swingarm.

 

Well... Didn't think of that!

It might actually work... I just love it when Honda uses standard dimensions on stuff... The most odd combinations of things just bolt up, in new and usefull ways...

 

i have a width of approx. 260mm. across pivot area on rc51 swingarm.

 

Ok, I got most of the parts now... The VTR swingarmbolt is 350mm end to end (one solid bolthead), and it's usable lenght (with the nut fully into the threads is 325mm...

With the stock swingarm and rearsets in place the clamped width is approximately 320mm... (I say approximately since that's pretty hard to measure in one go...) which leaves 5mm (Anyone wanna guess where this is heading?)

The CBR swingarm measures 291mm across, of which 3mm is the chain side collar sticking out...

Through approximation (wasn't able to dismount the stuff today) the stock swingarm shoul be around 280mm...

That means I'm about 5mm or so short... And the stock wheel bolt is shorter... only 325mm total an about 295mm usable...

 

Oh and on the question of lenght... the VTR swingarm is 515mm and the 929 swing is 550mm that is with measured to the same point (I used the "new" mark for the chain)

So that makes a difference of 45mm, should equal about 35-40mm in wheelbase... (adding the angle into the equation)

 

I think that this is too much.
VTR wheelbase is already long, to lenghten it it's not a good idea. IMHO.
Ciao

 

Riccardo

arent you the one who posted pics of vtr with cbr929 swingarm?
was that your bike or a find on the web?

 

My bike already have had the wheelbase shortened by ~15mm when the front end was swapped, so that means the total difference from stock should end up at 20-25mm...

To me, that difference is acceptable... Others may have another opinion...

Oh... It seems the best solution I can come up with for now is to make a custom adapter plate and bolt on a pair of 929 rearsets... That gives me the option to mill off 5mm in width on both sides, giving me the neccesary width for the bolt to fit...

And as a bonus I can make those plates with a bunch of holes and have the rearsets adjustable as well... Me likey...

 

I got a 954 swingarm from a friend... It looks like it's very similar in length and shock placement to the VFR swingarm... meaning, it looks like you will have to re-fab the header to make it work as the shock is to the left side of the swingarm... you guys noticing the same?

J.

 

Yes...I am!
The bike is not mine, I've find the pics on the web and I've posted them on the forum because the bike looks great. This does not means that it handles well!
Ciao