Suzuki SP400 Restoration

Suzuki SP400 Restoration

Suzuki SP40047 year old sales manager, Peter Goodier, openly admits to reliving his youth. “I had a series of motorcycles between the ages of 17 and 29, but then had to lay off then when my first child was born, after that, I never had the time, or the money, to get back onto two wheels. I did have a Suzuki SP370, reg AYF 965T if you are still out there, back in 1979, and it was a great bike. That machine did some serious off-roading, but I also toured with it, even going down to the South of France, two-up too, all taken in the Suzook’s stride. Now that the 3 kids have grown up, I have done what I always said I would do, and returned to the world of motorcycling, let me tell you, the wife is not amused.”

SP400“Once the decision to get back into biking was made I knew exactly how to go about it, there was an SP400 languishing nearby and it could be mine for a song, in actual fact it was free to a good home. This bike had been left in a Derbyshire Barn, completely untouched for 21 years, a friend of mine had parked it up, with no real plans for it and there it lay until recently. I had known it was there, but never had the time, or inclination, to even think about doing it up. My friend now lives in Holland and with him having no need or use for the machine, I decided that I fancied trying to restore it, my first go at such work, especially as it was so similar to the SP370 that I used to own.

1982 Yamaha SP400By the time I got it home, at the beginning of October 2007, I began to think that I had bitten off more than I could chew; I certainly wished I had taken on this project a couple of years earlier when it would have been in considerably better condition. It was so rusty, the wheels wouldn’t go round, there was no paint left on the frame, but just to make matters worse, there was still petrol in the tank, guaranteed to cause problems later as the minute passageways within the carburettor would turn out to be blocked. However as projects go it wasn’t all-bad, at least it was complete, it even had its original mirrors, and once the work started it turned out to be a real time machine, having laid unmolested for such a long time.

1982 SP400Over the next three months, the whole bike was stripped down, with all parts systematically polished, cleaned or painted. The fork inners needed replacing, and I was lucky to find a brand new pair at an Auto Jumble, I say, “brand new”, they were still 25 years old, they just happened to still be wrapped up in their original protective packaging. The wheels were very badly corroded, the alloy rims had pitted quite deeply, and the spokes had almost rusted through. I polished the rims back to life, and had the wheels rebuilt with stainless steel spokes. The exhaust remains very solid, with only surface rust, although the internal baffles had corroded a bit, judging by the amount of rust that came out them as I worked on the system. I have left the tank as it was as it in pretty good shape however, the rest of the paintwork has been re-done by me. Bike was finally started up during the last week in January 2008, and subsequently taxed and MOT’d on 2nd Feb, but it would not run at all smoothly, and back fired like mad at every opportunity.

Suzuki SP400 RestorationAt first I feared the ignition was to blame, especially seeing the size of the flames shooting out of the silencer but after careful examination this turned out to be functioning correctly. My attention soon turned to the fuelling and, in particular, the carburettor that had suffered so much from the stale fuel left in the system. After endless cleaning, adjustment and replacement of key Carburettor internals the running still wasn’t improved and after 2 months of searching, I came across a second-hand item, not the exact model for my machine, but a similar carburettor that I tracked down via a web forum dedicated to Suzuki DR400’s and other similar ‘Big-Thumpers’. It was fitted on Good Friday, and instantly better even before it was fine tuned for my engine. The bike now starts first kick, and runs smoothly throughout the rev range, completely unlike how I would imagine a 26-year-old Jap single should. The only parts I have needed, but have not been able to source have been minor, such as the odd engine-mounting bolt that, in the absence of genuine Suzuki items, have been easily substituted by bolts of similar dimensions. I would happily recommend Jeff Hall Motorcycles in Hillsborough, Sheffield, they have been so helpful, and they have more stock there than even they know. The project has been very enjoyable, plenty of problems, but all overcome with patience and hard work and I now have the restoration bug.”

SP400 RestorationThe SP400 is now for sale as a new steed has taken up residence in the garage, a 1983 GPz750 has forced its way into Peter’s affections, although he does say his wife isn’t so in love, just yet. The SP400 can be seen, and heard, as a video of the first runs following the restoration can be seen on Youtube, simply search for SP400 and you will find Peters machine in action.


Jeff Hall Motorcycles, tel 0114 233 3116,

Shirebrook Motorcycles , tel 01623 748 747

Wemoto spares , tel 01273 597 072,

The Thumper club

Top Tips:

  • Plasti-kote BBQ Paint – copes brilliantly with high temperature, is really easy to apply, and has a nice tough finish too.
  • Patience – take your time. When there’s so much to do, do one thing at a time.

1980 Suzuki SP400 Speciications

  • Price £ came free to good home (£885 new in 1980)
  • Value now (est): £800-1000
  • Power: 30bhp
  • Torque: 20ft-lb
  • Top speed 82mph
  • Dry weight: 136kg
  • Colours: Red, Yellow
  • Fuel: 8.6litres
  • Rake/trail: 29deg/146mm
  • Seat height: 790mm
  • Wheelbase: 1320mm
  • Engine: 396cc air-cooled cc (88 x 65.2mm), single-cylinder SOHC four-stroke. 36mm Mikuni carb. 5-gears. Chain final drive
  • Chassis: Tubular steel single down tube frame, 36mm telescopic forks, twin oil-damped rear shocks with adjustable preload
  • Brakes: 150mm single leading shoe drum front and rear
  • Tyres: 300 x 21 front, 400 x 18 rear

1980 Suzuki SP400 Restoration Gallery

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