Mk1 Aprilia RS125

Two Stroke on a budget – Aprilia RS125

Are you sitting comfortably? Good, then I shall begin. I am an old git. I was born in 1964 which means that when I reached the great age of 17 I was allowed to ride a 250cc motorcycle – something they stopped just one year later.

Aprilia RS125 Mk1 Back then the average 250 had been a fairly meagre device performance wise but it was still enough to make sure that plenty of adrenaline charged adolescents would never make it to adulthood or would spend the rest of their lives walking a bit funny due to broken legs. Most of my apprenticeship was spent visiting various people in hospital with bits of metal sticking out of their legs, yet somehow it never put me off. The steed of choice for me at the time was LUT 552P a rather sad old Kawasaki KH250 two stroke triple that was blue but the paint was so bad somebody put a tank bag on it to make it look slightly better. As £350 was all I had managed to save from my first year of work it was affordable and I loved the noise it made. I ran it on Castrol R30, my favourite occupation at weekends was to polish the hell out of it and then take it for a burn up along the Odiham bypass. If I went round the roundabout at the end fast enough I could still smell the pungent aroma from Castrol’s finest on my way back. On a summer’s day it was the finest activity – so good I felt it should be compulsory. It wasn’t though, they banned it a year later by bringing in the 125 law that said any bike you could have at 17 had to be under 125 and no more than 12 BHP.

I suppose looking back they had to do something – the KH’s and air cooled RD’s at the time were pretty quick, power output was around the 26-30 BHP mark, enough to do a ton if your speedo was optimistic enough. The death knell came when Yamaha brought out the LC models, they were properly quick. Tuners like Stan Stevens were getting big numbers out of them and the game had changed.
When the 125 law came about nobody wanted the 250’s any more, no matter how quick they were. I mean, why would you? You could take your test on a 125 and get straight on a Z1000, the fastest production bike back at the beginning of the 1980’s. That particular decade saw remarkable developments in the biking world – the 250cc Kawasaki KR1S of 1989 had the same top speed as the Z1000 of 1980 – everything had power valves and computer designed this and that – engines were producing way over 100 BHP per litre – the world had gone mad.

Because nobody wanted the little 250’s with their now pathetic 30 BHP in their 120+kg frames their value fell to two parts the square root of bugger all – my beautiful baby selling for a mere £300 even sporting it’s repainted black tank and gold stripes that made it look really special.

All of which brings me to the purpose of this project, you see that £300 KH250 would most likely be in the £4-6,000 range if it was still around and in good nick – show quality ones go for a lot more. For some reason the two strokes of that era have become objects of serious desire to old blokes like me and prices have responded accordingly. It’s not just the larger bikes either – mopeds like the Suzuki AP50, Yamaha FS1E and Honda SS50 (the holy trinity) are now going for almost as much and so are the parts. Just the other day I saw a rear light for a FS1E, it was in fair condition with quite a bit of surface rust but it was restorable, the guy wanted £100 because “he didn’t want to take the piss”. Ironic really.

Aprilia RS125 Mk1 fairing panelsAnyway I went to see my mate Scottie Redmond and we got in to this discussion about how it’s a shame people don’t get the fun of a well set up two stroke any more because they were simply outside of most people’s hobby budget. That got me thinking and we had a look round Scott’s stock to see what he had. In the corner was a very sorry looking Aprilia RS125, he had picked it up some time ago in a partly stripped condition and it was now buried behind a Yamaha Exup 1000 and a GPZ900 looking all forlorn as if the bigger bikes had been picking on it.

The brain whirred away and I thought that maybe if I could get it cheap enough I could do it up and turn it in to a real little rocket ship at a sensible budget. I ended up getting it for just a bit more than I sold my beloved KH for all those years ago – he even through in some side panels that had been decorating the walls of one of his other storage units.
I will stress – this thing is nasty at this stage, neither I nor Scottie have seen or heard it run, it’s been unloved for many years and anything that is rubber needs replacing. The price reflected that though so it’s all good, I think it was a great deal because I could see the potential. Nice examples of these bikes are going for about 1500 so getting one that was almost complete for a bit over 1/5 of that seemed like a good start. To add to the excitement it turned out to be one of the full power models rather than the pathetic restricted 12BHP models that are much more common. This little imp has a power valve in the exhaust port which pushes the power up to a rather respectable 30 odd BHP – as much as my old KH but half the weight! It was loaded in the van with no dramas and I set off on my way home with a big smile on my face, today was a good day.

Aprilia RS125I am not going to make this a show bike – this project is about encouraging others to seek out the bargains that have been neglected and to bring them back to life. This particular bike is a 2000 model it has about 18000 KM on it and was last used in 2009. It still had a tank full of two stroke oil and the tyres, although perished, look to only have a few thousand on them. The next article will try to offer some advice as to what to look for and to help make the right buying decision. I bought this one off a good mate that I have bought maybe 30 bikes off in the last year – he always tells me what I am buying and has never let me down yet. Not all dealers and sellers are so honest and reliable so I will be trying to show potential pitfalls in the forthcoming articles. Garages all over the country are filled with part finished projects – the road to hell is paved with good intentions. This is all about trying to help folk turn those dreams in to reality, I will cover many common processes in depth – the things that can save you a fortune and save you a ton of time in trying to find those unobtainable parts.

Look out for the first part where I will be having a look to see what state the engine is in and generally assess the rest of what I have got. I got it so cheap I don’t really care what needs doing, I know I won’t lose out on this one. Ta ta till next time. Dave.

Article provided by David Powell of Boston Bike Bits.

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