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Rider Reports on Suzuki TC305 Suzuki TC305 by Joe W Richardson (Sep 2005) The advert pronounced Suzuki 305 Streetfighter £450 and the year was 1993 with the importing of motorcycles and spares by the container load from America in full swing.  The bike was just one of a dozen others being advertised as ‘recently in’ by a breaker/importer in the NE of England.  But what was a 305 Streetfighter?  A phone call confirmed it was a Suzuki two stroke twin, it had ‘305’ on the side panel and it looked Hustler like, ish, well sort of.  So off I went for a look and sure enough it was a 305 with raised exhausts, bump plate folding footrest etc.  I had heard of 305’s but had not seen a picture of one with raised exhaust before.  It was missing the LH silencer and the LH carb (huh, why???) but other than that it was complete so I bought it. Once home, the bike was checked over and apart from one rusty fork bottom the chassis seemed in good condition.  Paintwork was reasonable with only minor rusting evident on seams etc.  One or two small items were missing as well as the above already noted parts but as these were general Suzuki bits it should not be a problem.  Unfortunately, the engine was another story with both bores and pistons badly corroded plus the crank had filled up with 30 years worth of desert sand.  Remarkably the rest of the engine was in as-new condition plus the 305 crank was a standard ‘twin’ type used in a multitude of the later 250/350 bikes and thus readily available as a spare.  The only specific 305 parts needed for a rebuild would be replacement pistons for a rebore, LH carb plus the silencer.  All in all, with ‘stuff’ coming over from the US in increasing quantities it I thought that it should be no problem to get the parts needed. You know, ‘should’ is an extremely good word.  It implies a blind optimism of certainty and is a word that with 20-20 hindsight should not be used in a sentence.  Doh!!!!  After deeper research it turned out that the bike was rare even by rare standards being manufactured for just one year and exported only to the US. For the next six months I searched everywhere I knew for the bits.  No new parts were available and the only second hand parts were on another TC that had been imported by DK near Stafford.  This one however was not for breaking at that time.  So that was that, I could have used T350 silencers to get the bike on the road but without pistons and a carb the rest would not happen.  Admitting defeat, the bike was put into deep preservation i.e. piled into a number of boxes and then assigned to the bottom of the overhaul list. Move forward eight years and a chance visit to DK’s after the early Stafford show in 2002 found that their TC305 had still not been sold.  By now it was in a bit of a state with broken instruments, missing tank, seat, side panel and air box but, it had a good LH silencer and its carbs.  The price tag was still £600 and a number of other restorers had looked at it and backed off at that price.  After all who had the parts to complete it?  Not I, but combining the two bikes would bring completion of one that much nearer.  Additionally, if I didn’t buy it then both bikes would probably be destined to remain as ‘failed’ restorations, so with some other bits thrown in I bought it. The original bike was taken out of storage and the years had not been good to the paintwork.  It had started to peel off in many areas and a full respray was now required thus delaying the rebuild until early 2003.  On the plus side, the chromework polished up very well and all alloy parts were mirror polished with the heads and barrels blasted.  The engine in the second bike was in a worse state than the original bike with bores very poor and the LH barrel missing top fins.  New pistons still had not been found so the bores of the original bikes barrels were honed as they were not too badly worn.  The pistons were bead blasted clean with rings in an OK condition and so with a reconditioned crank the engine was rebuilt.  Unfortunately the carbs on the second bike were badly corroded and a pair of later model T350 carbs were used.  The main and needle jets on later carbs are totally different but I figured they would be OK for low throttle running even if they didn’t work properly for large throttle openings.  The rebuild was completed with the usual new tyres, chain and sprockets, etc. Finally in late May 2003, 10 years after the original purchase, the bike was fired up.  The engine ran smoothly though the top end was somewhat noisy even for a two stroke (marble’s being shook up in a baked bean tin comes to mind).  Hot compression was taken at 130 Psi which wasn’t too low so after test running to settle everything down the bike was taken for an MOT and then Registered.  The bike lacked any real pull in sixth gear so the 15 tooth gearbox sprocket was changed for a 14.  This improved matters but it was obvious a ‘rebore’ was required. At this time E-bay was beginning to make itself felt in the search for restoration parts and as luck would have it a complete TC305 was found in the US.  The bike was in good condition and being broken for spares simply because nobody wanted to buy it.  This was the answer to the question of what to do with the second bike from DK’s.  Though I could not afford the shipping for a whole bike, I bought it anyway and had everything bar the wheels, frame and engine bottom end shipped over to England.  The result would be enough parts to make a second TC305. I also had another US contact that sent me a pair of T305 pistons at plus 0.5mm so I could rebore the original bikes barrels.  However, on removing the barrels the new pistons dropped straight through the bores.  What’s this, the original pistons did not have oversize markings on so they should (that word again) be standard?  Yup they were standard; that is standard T350 pistons. I will digress.  The T305 was an interim model between the previous T20 (super six) and the later T250/350 models.  The engine was designed as a 250 and the 305 was a bored out version but, the bored out version was released first.  Sounds strange and a bit back to front? Not really.  Suzuki already had a good 250 in production so its replacement could wait until development was concluded plus they had just released the T500 twin.  What was needed was something in the middle a sort of ‘super’ 250 hence the 305.  This was rushed into production and though OK it was to show a lack of engine ‘development’ However, a 305 doesn’t really come over as being much bigger than a 250 and 350 would sound better.  Unfortunately the barrels of the 305 could only be over bored to +1.5mm before loosing structural integrity (as they say in Star Trek).  To fit bigger barrels (or increase the crank throw) to give 350cc would mean a re-design.  The result was to make the bore +1.0mm above the 305 giving 315cc which left one rebore size still possible.  The ‘missing’ cc’s would be ‘miraculously’ added by the marketing department by putting a ‘350’ badge on the side panels. To continue then.  The barrels already at plus 1.0mm were bored out to take T350 pistons at plus 0.5mm.  The porting of a 350 is somewhat different to the 305 necessitating the piston cut-outs and skirts profiled to suit the 305 barrels.  Once rebuilt the difference was immediately apparent with the engine pulling well even at running in speed.  Unfortunately it was now obvious that the 350 carbs were not suited as the engine was running very hot.  The originally fitted ‘standard’ 350 pistons had not been profiled and made the barrel porting act more like a 350 thus the carbs matched.  With the re-profiling of T350 pistons at plus 0.5mm the porting was then correct for a 305 and consequently 350 jetting would result in weak running. A few weeks later the parts from the stripped down TC arrived from the US.  The carbs appeared in much better condition so were cleaned and fitted to the bike.  Running performance was much better but the engine still seemed to run hot however, this could have been due to the large raised exhaust pipes running close to the barrels and thus reducing the cooling effect.  Though smooth at 4000 Rpm, the engine ran very rough below 3000 rpm and tend to four-stroke badly showing it was running rich at small throttle openings. Over the next few weeks the carbs were to give a lot of trouble with intermittent running and poor idling, this was eventually found to be caused by bits of grit in the idle drillings.  I must have stripped and cleaned them about six times including blowing through with air but every time another small bit would block the idle jet after only a short time with the engine running.  The final solution was an overnight soak in chemical cleaner thus removed the last of the corrosion in the drillings. It was though all to come good and on the bikes first long run out it was awarded first prize in the VJMC show at the Whitby Regatta.  At this show you just turn up and all the bikes are parked in a row next to the sea front road.  The public (and other riders) are then asked to vote for the best bike in the show.  The TC is quite stunning with the large high rise pipes either side a very prominent feature.  It received the general public vote and many other bikers thought it was a stinger so it got lots of the ‘biker’ votes as well.  OK, to those who know it looks nothing like a stinger (I have a handful of them as well) but I didn’t mention that until after the prize was given.   The bike draws attention when parked due to the unusual look and the fact that it is quite large and very ‘shiny’ compared to the modern ‘plastic’ off road types.  Youngsters seem especially enamoured and they are quite surprised (and disappointed) to find it is not a new model but in fact over 35 years old and therefore not available from any bike dealer. Just to be sure with regards to the rich running, the better set of standard barrels were rebored with plus 0.5mm pistons and fitted in lieu of the well overbored pair.  As of Sep 05 running in is just about completed however the engine performance is still the same and so the carb needles were lowered slightly to weaken the mid range and this has helped somewhat to negate the rough running at low revs. To summarise, the bike goes well on the open road and handles pretty good for the era but the lack of engine development prior to release is obvious.  Despite trying a number of fixes, the engine still badly four strokes at ‘town’ speeds and is a real pain.  The gear ratios are also poorly thought out with an especially large jump to top gear.  Looking on the positive side, this ‘false start’ did allow the 250/350’s that followed to have all the little foibles of the 305 engine ironed out before they went into production.  The result for the later bikes was porting that gave very good running throughout the rev range with well though out gear spacing. The TC305 is a very rare bike as I know of only two others in the UK that may be fully roadworthy with perhaps a few more kicking around in the restoration stage (one of them is in my shed)!! Finally, the TC’s road brother the T305 is probably even rarer in the UK and funny old thing, I also have two of them; but that’s another story. Top of Page