Suzuki K 50

Remove SUZUKI GSXR-SRAD Seat Unit Replace with GSXR K Series Back End

The Complete Conversion

Instructions by Dave Nix (Nixey)

I have researched this project and am confident of a good result. (I am an Engineer and am certain it will be as safe and strong as the original bike)

I need to be able to carry a pillion occasionally so I am doing the full K series tail swap.

Items you need to buy are listed below, the prices quoted are what I paid for the parts to do my conversion. You may pay a little more for some items or even less depending on the level of interest on Ebay

Seat Sub frame, Ј60 (inc. postage)

Seat unit plastics, Ј25 collected locally

Seats, Ј50 inc. postage

Rear foot pegs, Ј20 (inc. postage)

Original Under tray, Ј10 (+ Ј5 postage)

Original rear light unit. Ј5 (+ Ј2 postage)

I am also going to fit a K 2 seat lock but the SRAD one will do if you can’t find a K series lock.

(All the parts are from either a, K1, K2 or K3 GSXR 600 or 750, or parts can come from a K1 or K2 GSXR 1000 but not a K3 1000 because these use a totally different frame)

The first thing is to strip the rear end of you GSXR and remove the SRAD seat sub frame.

Now you will see that the SRAD and K1 sub frames are quite different, the top rail of the sub frame is fine and needs no alterations. It is the bottom sub frame rail that need to be shortened,

Now you need to prepare the K sub frame for cutting; see Figure 1 below.

Figure 1

When the welds are filed down if you look closely you should see a very faint line where the fixing lug joins the sub frame.

Using a set square mark a line where the fixing lug joins the Sub frame. And mark all the way round both of the sub frames lower legs.

Suzuki K 50
Suzuki K 50

Cut along the line to a depth of about 1.5mm then cut along your next mark until you have cut all the way round the 1 st leg. Now the fixing lug should come out and you will have something closely resembling this. Please see figure 2 below.

Figure 2. Use this lug as a template to mark the lines to cut along on the other leg of the sub frame.

This is the easiest way to ensure both legs end up virtually identical lengths.

Now Cut approximately 1 3 / 8 from each of the lower subframe legs.

The Sub Frame can now be mounted loosely on your SRAD using just the top 2 mountings. You may have to file a little from each top lug to allow the sub frame to clear the main frame.

Please see Figure 3 below

Figure 3

Now the subframe is on you have to decide, do you want a Standard look or a Jacked up tail end.

If you want it to be Standard it is just a matter of fixing the Footrest to the Sub frame and then fasten the exhaust clamp to it’s mounting on the foot peg. Please see Figure 4 Below + Note at foot of page.

Figure 4.

Now I temporarily fitted the 2 lugs, which I had sawn off earlier. I fitted them the wrong way round just to allow me to accurately mark the position of the final cut. Please see Figure 5 Below.

Suzuki K 50
Suzuki K 50
Suzuki K 50
Suzuki K 50
Suzuki K 50


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