The Buff Has New Shoes !

The 1975 GT750 Water Buffalo is starting to take shape. One of the things I had to attend to first of all was to replace the right rear upper shock mount which had been damaged beyond simple repair by the previous owner. To do this I had to grind out the welded plug, and substitute a replacement from a donor frame. This took a couple of hours, but it can now be welded up and should be as good as new.

The other item I wanted to look after, was to update the rear wheel to be a disc brake rather than the stock drum brake as you see to the left. What I’m looking to create is an approximation of what a 1978 GT750 might have looked like, had one actually been built. Adding a rear disc brake is a logical assumption as Suzuki did introduce this with the four strokes that replaced the GT series. The donor bike frame I have is a 1977 GS750, and it shares many of the same components with the 1977 GT750 frame, although the actual frame itself is quite a different design due to the engine differences. As it turns out, the swing arm, with the disc brake fittings just drop into the GT750 frame. The lower shock mounts are different, as they are a clevis mount on the lower fitting, but otherwise just bolt on. The front forks, triple tree and brakes likewise are just a bolt-on fitting, with the GS750 calliper under slung behind the fork, rather than in front of the fork as on the GT. At this point I haven’t decided whether to go with a single front disc, or dual front discs.

So far so good – the interesting bit it where to put the master cylinder for the rear brake. With the GT frame, the oil tank is in the way as of course these were not required with the GS750 engines, and so space is at a premium. To check the clearances, I ‘dry mounted’ a scrap engine I keep for parts in the frame, with the Gibson expansion pipes mounted as well as the air box, oil reservoir tank and side covers. I want to use the round fluid reservoir, rather than go with a newer square style as those weren’t common in 1977/1978, as again I’m going for a look that is a natural progression from the last real GT750 model, made in 1977. The mockup can be seen to the right.

I realize that a lot of people remove the stock GT750 air box and just go with individual filters on each carburetter, but that isn’t the look I like, plus I already have a few new foam air filters that are available from either Twin Air or Moto Air – interestingly, both are Dutch companies, but the Moto Air prices are better. Both companies offer replacement filters that are exact matches for the original factory foam filter elements, for less than what you pay at your friendly local Suzuki dealer as filters by themselves are not readily available. From a dealer, you have to buy the filter mounted on the wire support frame which adds cost. Just changing the filter element and recycling the old wire frame makes more sense to me.

This evening I checked with a few colleagues at the Calgary Loyal Order of Water Buffalo sub-group of the Rocky Mountain Section of the Canadian Vintage Motorcycle Group (CVMG), to see what John and Fred thought about mounting options for the master cylinder. That was a very useful discussion, and I’m glad I waited to get some additional input before finalizing the design. Now that I have a better idea of how it should look, I can move on and modify the rear brake lever and stop switch assembly, grind off a few redundant tabs, scout around for a couple of parts – possibly off a Suzuki GS1100, or perhaps a Kawasaki or Honda of similar vintage, and also have some additional welding done.

At the moment, I do like the look – with the new pipes on, the recycled rear wheel and disc, swing arm etc., it looks ‘right’. Of course there is still lots of work still to be done…

The ‘home’ site for the project is here.

This entry was posted in Motorcycle and tagged , , , . Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.