Swingarm Conversion and Frame Reinforcement

[steve murdoch icoa #5322]

George, it actually is a '93 VFR arm.
Remember, i am the third owner of this project so getting details has been sketchy.
The work was done by Leitner and Bush. Canadians would know the shop for building race bikes in the '70s and '80s. Gord Bush is still building VERY fast engines in the Toronto area.
From what i was told, 2 VFR arms were grafted together to "fill-in" the area behind the mounting bolt and to allow a shorter Penske shock to mounted on top of the arm.
As far as the massive main downtube on the frame, the bike was being built for the track.
There are a couple pics in the "CBX photos", if someone would be so kind.

[Don #6141]

There you go!

Don

[steve murdoch icoa #5322]

Thanks for posting the pics, Don.

[cbxtacy]

Looks cool, I like the handle bar clamps and bar. The following is my opinion and I could be wrong.
1. Frame bracing accomplishes one thing-makes the frame heavier. I've had three different CBX's on the race track. Two of them I roadraced for a few years and one of them I did track days. The major malfunction in the handling department was ground clearance. They had the same ground clearance as a stock CBX and I was always able to ground things into the asphalt before the handling got scary. Never braced a frame.
2. Aftermarket front forks. You can get all sorts of stuff for the inside of them to make them work really good but I have yet to see one that gives the same ground clearance as a stocker. Forks by Frank will make longer then stock tubes for certain front ends but not for modern ones. The big difference is all them nice, modern, light (thin wall) forks are too thin in the wall (makes them light) to where Frank is worried about liabilities to make longer tubes. With the ground clearance you lose with the nice modern front end and a 17" front wheel you start grinding metal into the asphalt long before the improvement in the suspension components becomes noticeable. Pretty much any 41mm and larger front fork is thin wall and Frank won't make longer tubes. He will make longer tubes for the prolink CBX front end. And he'll make longer ones for the 35mm CBX front. Why would you want longer tubes for a stock CBX front? It's fairly easy to install a CBR600F3 front wheel on a prolink CBX. With that wheel and 1.5" longer tubes you have your stock clearance back.
3. Wheel/brake selection. Three things to look for-tire selection, braking capabilities and unsprung weight. A 3.5X17 wheel gives the best tire selection. You'll want floating rotors and preferably over 300mm dia. And a wheel/brake combo that cuts the weight by half (the CBX wheel/brake is heavy, real heavy). Another advantage of the CBR600F3 front wheel is the rotors are the same dia as the prolink CBX. You can use the F3 wheel with the CBX calipers.
The CBX has floating calipers and fixed rotors. Most older bikes came that way if they had disc brakes. Most modern bikes have fixed calipers and floating rotors. It's okay to have floating rotors and calipers.
4. Long vs short swingarm. All the modern sport bike manufacturers are making their wheel base short as possible and the swingarm pivot as close as they can to the engine for longer swingarm length. Why is longer preferable? Lets say someone is breaking into your garage and you need something to bludgeon them over the head with (you expect me to keep this post serious?). Longer would probably do more damage.
I don't want to discourage you. Most people never even come close to the capabilities of what they are riding. If you have a modern sport bike and leathers with knee pucks and have touched the pucks down while negotiating a turn you might be disappointed. I used to roadrace a Kawasaki Triple, a 750, scary. Once I touched my left knee down in a turn. Then I touched my right knee down. In the same turn. Almost simultaneously.

[Mike Barone #123]

Looks cool, I like the handle bar clamps and bar. The following is my opinion and I could be wrong......
.........I don't want to discourage you. Most people never even come close to the capabilities of what they are riding. If you have a modern sport bike and leathers with knee pucks and have touched the pucks down while negotiating a turn you might be disappointed. I used to roadrace a Kawasaki Triple, a 750, scary. Once I touched my left knee down in a turn. Then I touched my right knee down. In the same turn. Almost simultaneously.

My Reply: The CBX is sensitive to pivot bolt to axle lengths that are shorter than stock by say more than 13mm. Turn in at slow speed is too quick....at a faster pace it is about neutral. Getting the 120 off the rear with a 160 is a massive improvement. 110 or 120 out front is a great combination with 160 vs 100 and 120 stock CBX