Radical tail chop

[Bitza]

Hi all, OK the thought of today why not just chop off the back of the heap and replace it with a carbon fiber unit, with the original seat on top? I'm sure someone will have already done this. Looking at the bike's back end it is all a bit of a mess of odd bits bolted together, and the hand holds while handy when putting the bike on a stand are ultimately just there for the ride. (I'm also not aching to carry any pillion passengers).


I've marked on the pics the approx cut lines in orange, my current thinking is to have two stubs on the CF unit to fit up inside the open frame tubes where they have been cut (secured with glue and ali rivets), and to also utilise the two small brackets currently used to hold the underseat mud flap. All thoughts & references to similar mods gratefully accepted.

[utopia]

I wouldn't do that.
I would be far too concerned that the replacement would have inadequate strength.
Even using the little brackets to which you refer (which were never designed to be load bearing anyway) the attachment points would be so close together that you would be creating a virtually unbraced cantilever ie there would be almost zero triangulation.
I know you say there is little chance of carrying a pillion but what about touring luggage and suchlike ?
And personally, I wouldn't trust glue and rivets on such a joint.
If I was going to mess with it at all I would be more inclined to go the whole hog and change the seating arrangement to solo only, thus eliminating the problem .. or else just do a standard short tailchop.
And in my opinion the grab handles (which are useless for pillions anyway cos they're in the wrong place) are nevertheless very handy indeed when wheeling the bike around. I value mine. They're also useful when strapping luggage on.

On a slightly different tack, I seem to remember Kato fitting an aluminium rear subframe from one of the superbikes .. but it was ages ago and my memory of it is sketchy.

And thinking laterally, if weight reduction is your obsession then why not consider the single can Termi exhaust system that Darren flagged up a couple of days ago ?
It has the bonus of adding simplicity too.
Unless of course you're one of those folk who need to see a visually "balanced" exhaust with a can on each side. And fair play if that's your thing but personally I like the lob-sided single can look.

[stopintime]

MOT issues?

Maybe.... cut the grab handles, do a (partial) tail chop, smaller tail light, delete/reduce rear wheel hugger and/or delete/reduce side panels.

[Jez900ie]

Originally Posted by stopintime

MOT issues?

Maybe.... cut the grab handles, do a (partial) tail chop, smaller tail light, delete/reduce rear wheel hugger and/or delete/reduce side panels.

Deleting the the undertray & side panels simply exposes wiring to more road dirt, particularly if its raining.. There's little or no weight saving from doing this, but you do lose a lot of aesthetics.

The handles can be useful albeit rarely. More work to remove them than gains from doing so imo They always seemed ugly though to me and caught my eye. Then I painted them black and I really don't notice them anymore.

[slob]

I’d want to make sure there was 1/2” plus behind the weld on the tube coming up from the rear engine mount. Then grind off the remaining grab handle.
As others have said, probably best to remove the pillion padding/fit cowl and remove any rear pegs. Maybe fit a single race seat?
As ever, keep in mind that an insurance company could regard a tail chop as a write-off.

2-1 pipe is a great idea, sacrifice a couple of HP for a weight saving but the 900 system ins going to be a bit of an arse to fit to a 1000DS.

Check out the DesmoDue racing calendar and have a wander round the paddock for inspiration.

[Albie]

If I were to doing this I would join the frame that you cut with a round half circle then a lid just to keep strength and beauty. I would hollow the seat on pillion like my 1100s performance seat so its solo but had a carbon cover same as stock except vented. You can choose to mount light still but less weight. Lose the pillion footrests and chop the handles . The seat lock hmm re routed.

[Albie]

https://images.app.goo.gl/CJhxw42BRzaw9F3o7

Mine was,a,£625 seat upgrade but as I said hollow with this seat cowl specifically made for it. It had the same bolt side fittings but a bracket under the rear to fix to seat base. Vented on the top too.
What I'm getting at is you could do similar with old school cowl if you were brave with vents or scoops and build in lights. I never mention indicators because people do what they will legal or not. But you see what I'm getting at. Simplify what's there.

[Bitza]

This the kind of thing I'm thinking of, sorry for the very crude graphics.

As is.

The thinking so far.

Couple of things, in front of the indicator it will flare out in line with the edge of the seat, giving a grip/handle. The glue isn't so much for sticktion but rather to ensure a good fit of the CF stub into the frame tube end, the 2 rivets set at 90 degrees do the securing & the two small brackets simply provide additional location (not so much support). Finally yes it would make it a solo machine so off come the extra foot pegs.

[stopintime]

Not bad.

Maybe a factory seat cowl, trimmed down (or actually up) to lign up with your piece?