Well it's been a year and the last time i posted i said i would be going through a CBR600RR tail end conversion.
It is now finished and the outcome is really spectacular. Thanks go to SC33 for the initial framing of the idea.
As the old posting describes, the idea was to put a CBR600RR tail cowl on a VFR. On further consultation with SC33 the VFR was found to be a '94 model.
This posed a potential problem, my VFR is a '88! Would the modification work on an older model?
After purchasing a CBR600RR 2003/2004 sub-frame off ebay for £75 (inc p+p, and all brackets attached!) and a cracked cowl that i plastic welded (£10 also on ebay) it came to the strip down of my VFR.
I completely disassembled the rear end, even removing the old sub-frame as the CBR cowl was in no way going to fit. I offered up the CBR sub-frame to the bike and immediately knew that a something a bit special would be required.
On the later versions of the VFR, the sub-frame attachment points are further up along the main frame. On my VFR, the sub-frame attaches at the first foot peg bolt and on the frame underneath the tank.
I would have to design a new sub-frame attachment, and completely redesign the layout of the undertray.
I used the top arms of the VFR sub-frame with some brackets made from steel and then welded them to the arms for the top CBR sub-frame attachment bolt hole.
Top Bar 1.jpg
Top Bar 2.jpg
Top Bar 3.jpg
I used washers to pack out the gap and some high tensile strength bolts to attach the CBR sub-frame.
The bottom attachment point was going to be a bit tricky. I needed a way of bolting the sub-frame in place without compromising the geometric lock of the turning force about the top sub-frame bolt.
So i made two full cross-members out of plate steel and welded each side together. Some paint and i was ready to fit the sub-frame.
With the sub-frame now fitted and all bolted in, i set about the job of making the undertray of the CBR fit the VFR and all the VFR components (battery, flasher relay, r/r, radiator overflow, No 1+3 coils, fuel pump, main electrical loom, cdi) fit into the CBR undertray.
With a bit of relocation of some components and some splicing of some wires, everything was now in it's new place.
The last problem were the closing panels that sit underneath the fuel tank. The VFR ones would not fit completely and neither would the CBR ones. So i again used both and fabricated a closing panel from both.
The project now complete, the bike fired up (eventually! It had been sat outside for 4 months) and all electrical connections tested. Amazingly, after all that i had been through, the only thing that was wrong was that the left and right rear indicators flashed the wrong way.