Swingarm brace install + Underslung caliper mount
12-28-2013, 07:03 AM
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Swingarm brace install + Underslung caliper mount
So another swing arm brace install thread.. WHY?...Why not the internet is free 
Bike is a 1998 (built Jun 1997) VTR1000F
Donor swing arm is a 94 Honda CBR 900rr
I choose the early year (pre 1998) 900rr because I wanted the brace with the box style front leg. I believe it makes a more stable, better looking swap, then the twin leg version.
The 1998-1999 CBR 900 rr used the twin leg brace.. and I've seen it work out ok, but the sculpted part needed for clearance near the shock, just never looked right to me.. cept one, and that rider boxed in the two legs with sheet aluminum once they were welded.
The 2000 CBR900rr uses a much different swing arm and the brace is not really useable for this mod.
With the donor swingarm in hand, the project started by cutting off the brace
The OEM chain guard tabs were already cut off, so I will just clean up that work and fit a huger chain guard combo.. it does keep chain lube somewhat contained.
As I will be building a under-slung rear brake caliper mount for this MOD, I do not need the 900rr caliper bracket, or the bracket stop from the swing arm.
I will be machining off the OEM caliper bracket stop from the VTR arm as it will no longer be used .
Next step is machining up a caliper bracket strut mount to be welded to the swingarm.
I have ordered materials for the strut, so waiting on those to arrive.
Fitting the brace to the VTR swingarm.. well waiting for that package from the guy in brown....(UPS) on Monday as well.
I'll keep this thread going with updates as I work things out.
Bike is a 1998 (built Jun 1997) VTR1000F
Donor swing arm is a 94 Honda CBR 900rr
I choose the early year (pre 1998) 900rr because I wanted the brace with the box style front leg. I believe it makes a more stable, better looking swap, then the twin leg version.
The 1998-1999 CBR 900 rr used the twin leg brace.. and I've seen it work out ok, but the sculpted part needed for clearance near the shock, just never looked right to me.. cept one, and that rider boxed in the two legs with sheet aluminum once they were welded.
The 2000 CBR900rr uses a much different swing arm and the brace is not really useable for this mod.
With the donor swingarm in hand, the project started by cutting off the brace
The OEM chain guard tabs were already cut off, so I will just clean up that work and fit a huger chain guard combo.. it does keep chain lube somewhat contained.
As I will be building a under-slung rear brake caliper mount for this MOD, I do not need the 900rr caliper bracket, or the bracket stop from the swing arm.
I will be machining off the OEM caliper bracket stop from the VTR arm as it will no longer be used .
Next step is machining up a caliper bracket strut mount to be welded to the swingarm.
I have ordered materials for the strut, so waiting on those to arrive.
Fitting the brace to the VTR swingarm.. well waiting for that package from the guy in brown....(UPS) on Monday as well.
I'll keep this thread going with updates as I work things out.
Last edited by E.Marquez; 12-28-2013 at 11:10 AM.
12-28-2013, 09:38 AM
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I don't believe the line drawing above for the 98-99 is accurate. The twin spar versions I've seen (in pics on-line) have the rear side of the spars enclosed. Are there variations of this design, anyone? I agree with the OP that the full box version makes for a cleaner finished install, but I like the twin spar look better. So, I'm torn, but will probably attemp a mod using the later year version 900rr brace. My idea is too cut the backside of the front spars down to allow a smooth blend with the shock cutout on the SH arm at the front of the spar. This would lower the front of the brace a little, but I don't think that would present any problems.
Erik, are you going to add tabs for swingarm spools?
Erik, are you going to add tabs for swingarm spools?
Last edited by VTR1000F; 02-22-2015 at 05:57 PM.
12-28-2013, 09:54 AM
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I don't believe the line drawing above for the 98-99 is accurate. The twin spar versions I've seen (in pics on-line) have the rear side of the spars enclosed. Are there variations of this design, anyone? I agree with the OP that the full box version makes for a cleaner finished install, but I like the twin spar look better. So, I'm torn, but will probably attemped a mod using the later year version 900rr brace. My idea its too cut the backside of the front spars down to allow a smooth blend with the shock cutout on the SH arm at the front of the spar. This would lower the front of the brace a little, but I don't think that would present any problems.
Erik, are you going to add tabs for swingarm spools?
Erik, are you going to add tabs for swingarm spools?
And yes, I've seen the 99's with the back of the two front legs enclosed.. but others with just the two legs or at least looked that way in the pics I viewed... in any case, I wanted the single boxed front leg, so picked up one of those.
What I did find is a lot of the ebay ads do not correctly identify the year of the swing arm, with many ads showing fitment from 1997 to 2000.
.. May be that they all will physically fit, but they are clearly not all the same. Yes I'll will be welding on tabs for spools
Last edited by E.Marquez; 12-28-2013 at 10:03 AM.
12-28-2013, 06:30 PM
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and smaller in what, material cross section? sq mm of contact surface one design to another? sq mm of surface area the boxed base spans compared to the other twin foot?
And then we have the fact the twin foot version is only partially welded to the swing arm (though, that is on the 900rr, a MOD'er could fully weld it on the VTR swingarm)
Have you seen how many of the twin foot braces are mounted? cutting away much of the footing surface of the right foot base to clear the shock? Some have cut most of the leading part of both twin foot base for fitment.
How did you determine one was "weaker" than the other? destructive testing? Computer aided software failure modeling?
Or was it a Mark I calibrated eye
Not a flame for your opinion.. just really wanting to know how you came to your opinion.
Thanks
Last edited by E.Marquez; 12-28-2013 at 07:01 PM.
12-28-2013, 06:35 PM
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12-28-2013, 06:51 PM
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Anyone have this version 900rr brace and can measure this?
Better if you can get three measurements for me.. the one depicted above, if you have cut the brace off already, the material thickness (cross section), and the depth of the foot front to rear.
Thanks
12-28-2013, 09:28 PM
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In my estimate any brace is an improvement.
This opinion is not based on fact ,but more on feel having recently used the box brace on my bike it just feels better and more settled on the road.
I also believe that the hawks have a certain amount of flex built into them that does nothing to help the bike when you fettle and improve the suspension and then combine that with the latest tyres that are designed for bikes with stiff chassis dynamics that don't flex like the hawk does.
Thats why I think that any brace will help the Hawk to feel taughter, especialy on undulating surfaces.
Just my 2 cents worth and a very interesting thread.
Please keep us informed of your thoughts and progress.
This opinion is not based on fact ,but more on feel having recently used the box brace on my bike it just feels better and more settled on the road.
I also believe that the hawks have a certain amount of flex built into them that does nothing to help the bike when you fettle and improve the suspension and then combine that with the latest tyres that are designed for bikes with stiff chassis dynamics that don't flex like the hawk does.
Thats why I think that any brace will help the Hawk to feel taughter, especialy on undulating surfaces.
Just my 2 cents worth and a very interesting thread.
Please keep us informed of your thoughts and progress.
12-29-2013, 07:50 AM
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Anyway, I will get that measurement for later today.
12-29-2013, 10:05 AM
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Just to confuse the issue here is a pic of my boxed brace.
As you can see it fills the space provided and still had to be relieved for the rear shock so that there was no interference.
Some folks cut 10mm of the boxed section where it mounts, I didn't do that and it all fitted up O.K.
As you can see it fills the space provided and still had to be relieved for the rear shock so that there was no interference.
Some folks cut 10mm of the boxed section where it mounts, I didn't do that and it all fitted up O.K.
12-29-2013, 10:24 AM
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From the rear.
And the top.
As you can see not much room to work with.
Am extremely interested in how the non box type brace mounts and what if any clearance issues there are with the rear shock!
I believe that the brace I used was from a 93-94 900RR but I could of been misinformed.
As I have a brace now I am more interested in the underslung caliper and am looking forward to seeing how this is achieved as I am not happy with the way my top mounted caliper looks and performs.
The Blade caliper bracket is big and ugly!! And in my opinion looks out of place.
And the top.
As you can see not much room to work with.
Am extremely interested in how the non box type brace mounts and what if any clearance issues there are with the rear shock!
I believe that the brace I used was from a 93-94 900RR but I could of been misinformed.
As I have a brace now I am more interested in the underslung caliper and am looking forward to seeing how this is achieved as I am not happy with the way my top mounted caliper looks and performs.
The Blade caliper bracket is big and ugly!! And in my opinion looks out of place.
12-29-2013, 10:52 AM
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Kenmoore, your install is what i plan on doing.
Not planning on cutting the front leg box.. but was going to weld in the rear legs, and the sides and back of the front leg... as well as the left portion of the front box, then use a soft faced dead blow hammer to form the right front part of the box to conform to the shock relief area of the swing arm...then complete the weld.
How was yours done?
Not planning on cutting the front leg box.. but was going to weld in the rear legs, and the sides and back of the front leg... as well as the left portion of the front box, then use a soft faced dead blow hammer to form the right front part of the box to conform to the shock relief area of the swing arm...then complete the weld.
How was yours done?
12-29-2013, 02:00 PM
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Just like yours , I cut the brace of the 900RR swing arm very carefully as I still wanted to keep the taper on the rear of the brace unlike some others I have seen that have been cut square to finish it off.
I didn't shorten the front box like some others have done and like you I used a soft mallet to relieve the front box.
I also thought about enclosing the brace to swing arm but didn't.
I now rate this mod as No 1 followed closely by the lightened flywheel.
Both mods transform the bike immensley.
I didn't shorten the front box like some others have done and like you I used a soft mallet to relieve the front box.
I also thought about enclosing the brace to swing arm but didn't.
I now rate this mod as No 1 followed closely by the lightened flywheel.
Both mods transform the bike immensley.
12-29-2013, 02:44 PM
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Brake caliper strut mount
Spent some time on the Mil today....
The brake caliper strut mount is done
Milled from 7075 Aluminum
I decided on a captive mount for the Spherical rod end, vice single sided.. Took longer to make, but will provide more strength.
Teflon lined three piece FK Rod end specs at more than 10,027 ftlb Static load... if this application needs more than that... the mount is going to get ripped off the swing arm...
The strut rod will be steel tube with tube ends weld in or 7075 Aluminum round bar... have not yet decided.
The brake caliper strut mount is done
Milled from 7075 Aluminum
I decided on a captive mount for the Spherical rod end, vice single sided.. Took longer to make, but will provide more strength.
Teflon lined three piece FK Rod end specs at more than 10,027 ftlb Static load... if this application needs more than that... the mount is going to get ripped off the swing arm...
The strut rod will be steel tube with tube ends weld in or 7075 Aluminum round bar... have not yet decided.
Last edited by E.Marquez; 12-29-2013 at 04:44 PM.
12-30-2013, 07:53 AM
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Cut the VTR caliper bracket down last night and did a little bit of finish work.
Realized doing it this way, besides having to remove the caliper to bleed, it will require a new brake line. Another $50 to the mod...
If Im spending another $50..... perhaps scrap this plan and go with a proper caliper to start with...
Thinking> Garage > 3rd beer = Bad idea
Fresh at it this morning and after some research... I think a rather common GSX1300R rear caliper and bracket may be a better option.
Buy in will be $60 or so, but I can re use the SS line I already have saving a bit.
The Hayabusa rear axle is 25mm dia, vs our 20mm.. but that is just making a simple bushing to correct. If the alignment of the Busa caliper and bracket is not good for the VTR, I can fix that by milling the Busa bracket, and or building a spacer as part of the bushing to get proper alignment.
The last concern is the distance from axle center to caliper pad swept surface area..
The Busa uses a 240mm disk
The VTR a 220mm disk
So 10mm difference in radius
I think this last point is pretty big, and makes the GSX1300 caliper bracket unusable... unless I buy a 240mm disk.... which adds cost and rotating mass I don't want.. Worse is I just bought a brand new 220mm Galfer wave rotor for the VTR...
Thoughts?
Realized doing it this way, besides having to remove the caliper to bleed, it will require a new brake line. Another $50 to the mod...
If Im spending another $50..... perhaps scrap this plan and go with a proper caliper to start with...
Thinking> Garage > 3rd beer = Bad idea
Fresh at it this morning
and after some research... I think a rather common GSX1300R rear caliper and bracket may be a better option.Buy in will be $60 or so, but I can re use the SS line I already have saving a bit.
The Hayabusa rear axle is 25mm dia, vs our 20mm.. but that is just making a simple bushing to correct. If the alignment of the Busa caliper and bracket is not good for the VTR, I can fix that by milling the Busa bracket, and or building a spacer as part of the bushing to get proper alignment.
The last concern is the distance from axle center to caliper pad swept surface area..
The Busa uses a 240mm disk
The VTR a 220mm disk
So 10mm difference in radius
I think this last point is pretty big, and makes the GSX1300 caliper bracket unusable... unless I buy a 240mm disk.... which adds cost and rotating mass I don't want.. Worse is I just bought a brand new 220mm Galfer wave rotor for the VTR...
Thoughts?
Last edited by E.Marquez; 12-30-2013 at 08:19 AM.
12-30-2013, 08:33 AM
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It's just another part, more cost. Which I would like to avoid.
Hmmmm, perhaps an off set bushing for the busa bracket.
I could bore the 20mm hole in the 25mm bushing off set...that could account for about 4mm. Leaving me 6mm difference
12-30-2013, 08:38 AM
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Crap load of work on a limited capacity manual mil.... and the material would be pricey ... plus one slip of a tool... wrong turn of a carriage hand wheel..and you turn a $$ Al billet into scrap
12-30-2013, 12:13 PM
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12-30-2013, 01:39 PM
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I don't know about you guys but when I do mods I get impatient and just want to get it done.
In this case I found it easy to follow the tried and proven method of using the 900RR caliper bracket but I don't like the look of it.
The effort required to undersling the caliper is worth it in my opinion as it gives the bike a totally different personalised look.
Of course cost is a consideration, and as I still wanted to ride my bike I had to purchase 2 used swingarms and a caliper bracket, then weld and paint, as well as buy a hugger.
My all up cost was approx $450- Oz and then there was my time as well.
Looking forward to the finished item
God knows what all this would cost if you got a custom builder to do it!!!
In this case I found it easy to follow the tried and proven method of using the 900RR caliper bracket but I don't like the look of it.
The effort required to undersling the caliper is worth it in my opinion as it gives the bike a totally different personalised look.
Of course cost is a consideration, and as I still wanted to ride my bike I had to purchase 2 used swingarms and a caliper bracket, then weld and paint, as well as buy a hugger.
My all up cost was approx $450- Oz and then there was my time as well.
Looking forward to the finished item
God knows what all this would cost if you got a custom builder to do it!!!
