Yamaha SRX600 Reborn. Part1.

I do not only customize bikes, as might attentive reader notice. I repair and restore some motorcycles also. I did that more frequently earlier but now I take only interesting bikes in work.

This story is about rebuilding Yamaha SRX600 (3SX 1991 model year), and it began in February 2012 when we bought this bike for female friend of mine.

Modern version of SRX is worthy heir of one of the finest single cylinder bikes of all times: the 1986 SRX600. New model has improved suspensions (with monoshock at rear), brakes, oil cooling system and equipped with an electrical starter. And it was redesigned a bit also, but still looks distinctive and is all-around bike also much useful in city traffic. New model was imported in very small amount to Germany and may be couple of them subsequently become a “grey” import to GB, but initially this model was intended for usage in internal Japanese Market.

The bike we bought had about 50K kilometers and was priced quite low (as for Ukraine, where imported bikes are priced higher than in Europe or USA due to import fees) but also had gloomy exterior condition and such list of visible damages:

• leaking front fork oil seals;
• traces of oil on rear shock;
• damaged tail plastic;
• some bolts and nuts were missed;
• fuel tank liner wretched and exfoliated.

It looked like lot of work, but nothing really worrying . Though It stated to be “interesting” when I went to bike maintenance.

It occurred, the apparent reason for fork leakage was not seal or bushing wear, but attempts the former owner  to extract seals with screw driver. Thus, tubes were damaged due to that treatment of course.

Such things could be repaired, but without any guarantee of success. So I decided to replace tubes with new ones. Here the difficulty was that modern SRX is internal Japanese model, and no manufacturer make spare tubes for it. I researched that FZR 600 (3HE) 92-93) tubes could be applied despite they are longer for a couple centimeters.

Damaged air box (wrecked mounting points and air filter set, all done by former owner) with unbelievable ugly handmade air filter was the next point.

Lack of original or spare air filter is yet one problem of bike’s Japanese internality, so I found that I can use KN stock replacement air filter from older SRX with some air box adaptations.

Work was resumed after all initial purchases were made, and parcel with them arrived to me. That was time when I worked in old garage, less useful for work than current one.

I rebuild the fork with new tubes, bushes and seals. As you can see on this photo, SRX and FZR fork tubes are pretty the same.

Repairing of air box was unthinkable until it was in frame. I needed to disassemble half of a bike to remove it. After that I disassembled an air box, fixed mounting points and adapted box for the new air filter.

There was nothing difficult in that work except I had to design pressing unit such like adapter between new filter and old pressing flange. Finally I designed and made it as simple and as useful as possible.

Other works were too ordinary to describe them: carburetors cleaning, tail plastic repairing, oil changing and so on. A couple of words about tires could be written. Stock tires had dimensions 110/70-17 and 140/70-17. Not a good idea in general, and in particular due to Ukrainian roads conditions. So I chose 110/80-17 tire for front wheel and 150/70-17 for the rear one. Rims of SRX600 are quite wide for these dimensions. In addition to all written above I replaced clutch cable with Yamaha TT660 (yep, yet another one victim of Japanese internal market) and bike became ready after that.

New owner assimilated her bike for 2012 season.

All went good except engine oil consumption. It became clear, that an engine top end needed rebuilding. But that wasn’t unexpected so far as all engines need this procedure after twenty years of exploitation. However, just rebuilding the top end seemed to be dull, so we bought oversized (+2mm) high compression forged JE piston and gasket set to make reserve for winter works.

And in February 2013 I began new stage of SRX600 works. Engine was put on working table and what was planned as an easy walk began to turn into long and effortful crusade.

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