Phat Trakka 2 - Swinger


The arse end of a GT750 is fat and shapeless.  On the stock bike those four pipes look quite pleasant but they hang low and wide like a fat old saggy .. well you get my drift.

What this bike needs is the flat track seat that I bought a year or so ago.  The seat has a vestigial hump at the back that really needs to be stretched out a little to balance the shear size of everything else,  Other than that, I think the back end really needs a set of good looking shocks to provide a tough back end look, and if they improve the handling, that can't be bad either.


Really, though, the stock shocks are old and ugly.  I have nothing against old or even plain, but they just are not up to the task of suspending this beauty.  Something with a little more flair and presence was needed. the old shocks measure up at 295mm between eyes and the ends are both nominally 12mm.

Another quick visit to Mike's XS web store and there are many shocks to choose from and all really cheap. The ones I chose for this project are 320mm long and have remove reservoirs which looks tough, like a cheaper copy of Ohlins but at 10% of the cost.  Let's hope that they work better than 10%. 

Of course the top eye was too large and the lower one was too small.

The top was easy.  I pressed out the bush and sleeve using a vice suitable sized socket.  Then I pressed out a bush from the stock shocks which was in perfect condition, and lubed it and pressed into the new shocks. 

The lower mount was a parallel wall isolastic type bush so I carefully drilled out the bush from 10mm to 12mm.  If it overheats, the rubber bushes will go up in smoke, so it took a while and lots of cooling. 



That should fix the suspension, but what about the bushes?  In a stock GT750 which weighed about 600 pounds and was a Superbike of its time, Suzuki decided that cheap plastic bushes were all that it needed for the swingarm pivots. Truth is that the rust in the steel sleeves is a bigger problem and this set were beyond their Use By date whichever way I looked at it.


On a prior GT750 project, I replaced those plastic bushes with bronze bushes from an aftermarket supplier and they were claimed to not need to be reamed to size.  That surprised me, because bushes with an interference fit, invariably have to be reamed to get the correct clearances. needles to say, that set were way too large on the OD and it cost me more to have them turned down to the appropriate size than they cost from the supplier.


Usually I'd replace the bushes with needle rollers.  Most of the Honda and Yamahas I did in the past used off-the-shelf needle rollers, but the GT750 has some very odd sizes. On further examination, it turns out that Suzuki used  bushes which were 1.125" OD and happen to have an ID that almost exactly matches a metric size.  What is that about?


So I have ordered a set of inch sized needle rollers and we'll see if they do the job. In the meantime I ordered a pair of new inner sleeves and new thrust washers from an on-line OEM parts supplier..



Swingarm page 2