It was whilst visiting a local classic car enthusiast and admiring his lovely 1960’s Pagoda Mercedes that I stumbled upon the old Honda; nestled at the back of an old wooden barn where it had laid untouched for decades. ‘Tell about the bike’ I enquired, rather more excitedly than I should have. ‘We got that thing years ago, used it around the farm’ came the reply. The story progressed and it was explained to me that the SL125 was not really a native of the UK, although very popular in the States and Australia. The Far Eastern countries still enjoy their reliability daily and this like many old Honda’s are very collectable across the globe. The number plate shows a Surbiton dealer, Tippetts, who have remained loyal to the Honda Marque for many years and the story goes that they took many of the 25 or so machines that came into the UK. First registered 13th September 1972 means this bike is a K1 model with the gas tank finished in Special Silver Metallic; as were the side panels, headlight bowl and mudguards.
My first question had to be ‘is it worth saving’? The Honda SL 125 only came into the UK in very small numbers, so parts are going to be an issue. With just a single cylinder 122cc it is certainly not going to set the world alight with blistering performance. Finally, is there a market for it once completed? This would be a decision I would reserve until the health of the trusty Honda motor could be evaluated. In the barn I had the foresight to check the engine turned over and although surface rust covered every inch of this 43 year old bike there were no gaping holes to be found in the frame or in fact the gas tank. Just a few days later the bike sat on my driveway and to my surprise the tyres still carried air from before the new millennium dawned but unfortunately the fuel tank also carried remnants of something put in at the same time. When it was pushed into the barn all those years ago it had several gallons of Shells finest which has turned to a solid rusty mess that enjoys the aroma of £1 shop aftershave.
I employed the talents of my wizened old friend Alan, veteran of many of my mobile calamities, including a Morris Minor and a rotten MGB; his enthusiasm for the Honda was overwhelming. Within two hours of arriving the little 125 sat with just the engine and wheels attached to the frame and closer inspection of the carb revealed that failure to drain means plenty of cleaning followed. Stripped and left in a bowl of paraffin for a week would certainly go some way to removing the solidified fuel, the majority would require a wire brush, small screwdriver and compressed air. The tank itself meant a repeat of the cleaning process I have carried out on a car before and that involves 12 bottles of distilled white vinegar at 37p each, two weeks of patience and a tub of baking soda. The final ingredient is spooned in with the vinegar to neutralise its tendency to eventually eat right through any metal. A blast with the jet wash and remarkably the interior of any fuel carrying vessel will look like new, for about an hour before, if not dried and lined with oil based liquid the rust will return with a vengeance.
The carburettor responded well to some TLC and was refitted to the engine and once a new 6 volt battery arrived we immediately enjoyed a neutral and oil light but not much else. First rule with these old Honda’s is don’t look too deeply into why there is no spark, it’s going to be something simple nine times out of ten. Cleaned the plug and checked the points gap, still nothing; slight concern now filled the garage but just by disconnecting then reconnecting all the ancient wiring the electricity began to flow. With the tank still full of vinegar I rigged up a large funnel connected to my sparkling carb and just five kicks is all that was required before the gentle ‘put’, ‘put’, ‘put’ brought forth scenes of jubilation mixed with amazement. No rattles or grinding noises and the little motor revved as freely as the day it left Japan; not wishing to undo all my good work by running with 20 year old oil I shut the engine down. Within another 30 minutes the motor sat on the bench and the rolling chassis was pushed into the greenhouse, snug and warm ready for the next stage.
Although I still haven’t made a restoration decision, the tank was drained, cleaned and endured a day being sanded within an inch of its life; the rust scabs were deeper than I would have liked but nothing a light skim of filler wouldn’t resolve. A coat of primer to lock in all the hard work was followed by many hours exploring the web based sellers, finding and pricing up all I need to put this old Honda back on the road; is it viable? I will pass on that info next time.
Honda SL 125 Specification
- Engine Single cylinder 4 stroke 122cc
- Output 12hp @ 9700rpm
- Top Speed 63mph
- 2 Valves OHC
- Gearbox 5 Speed
- Front tyre: 2.75-21
- Rear tyre: 3.25-18
- Front brakes: Expanding brake
- Rear brakes: Expanding brake
- Weight: 108.0 kg (238.1 pounds)
- Fuel capacity: 7.50 litres (1.98 gallons)