Hi there just wanted to check on a bultaco I've recently finished is it as claimed a 1978 machine ? Stamped rm 198 .The stamping looks like it was done by a 5 year old but understand this may be normal .? Thanks ?

The engine looks like a 198.  The frame I’m certain is not 198.  It looks more like a model 91 frame. The give away is the gusset at the steering stem and the vertical frame tube that extends from in front of the swingarm up to the upper frame tube.  So I would say the engine is 1978 and the frame 1972-4 ish.  Remember of course bultacos aren’t made by year.  But for licensing purposes you need to give it a year. I’m not sure what your jurisdiction requires ... approximate frame year or engine year. 

Steve 

Thanks for that Steve very interesting ,what's confused me is it's road registerd as a 1978 bike and both engine and frame are matching to that year . Who knows what checkerd pasts there bikes have. .

The tank and saddle combination look like a Sammy Miller aftermarket add-on. The exhaust is possible Miller as well, with the earlier type "Banana type" Silencer and Miller replacement Centre box. Otherwise the engine and frame look like a 198 to me.

The 250 is a nice bike and was somewhat overshadowed by its bigger brother the 325 in the U.K. However in France and Spain the 250 is highly regarded.

As Steve said, frame is an early frame, from the headstock and frame tube layout I'd say series 2 model 91/92 from 1973. The exhaust chrome pipe is an M92 type and is the same diameter as later 250 pipes. It's definitely not a 198 frame.

Engine looks to be a 198 type so if the numbering is not altered it should be the original engine. Maybe the original frame got damaged and someone acquired that one and stamped it to match.

I've recently had some issues with DVLA whereby someone was applying for a V5 for a model 92 Sherpa that belongs to me. Turns out he must have had the engine that my bike left the factory with and stamped a frame with that number to apply for an age related plate - I'm assuming he knew engine/frame numbers matched from the factory and that he could date it from the engine number. The frame number flagged up as already registered so I had to prove that I had the original. DVLA wouldn't show me photos of the bike that he was applying for but the police who came to inspect mine did and I couldn't believe what had been done. It was a later frame and looked as though it had had the frame number chiselled into it, so no surprise really if you have one that has been tampered with

On 5/5/2019 at 5:20 PM, woody said:

As Steve said, frame is an early frame, from the headstock and frame tube layout I'd say series 2 model 91/92 from 1973. The exhaust chrome pipe is an M92 type and is the same diameter as later 250 pipes. It's definitely not a 198 frame.

Further supported  by the use of top yoke with  taper-top stanchions - (on a 198 the top yoke would have 4-bolt split clamp with parallel-top stanchions.)

On 5/1/2019 at 12:54 PM, rusty nuts said:

claimed a 1978 machine ? Stamped rm 198 .The stamping looks like it was done by a 5 year old

If the frame is stamped RM198, it probably was - that's an engine number............. 

Tank/seat unit is standard Bultaco Slimline/Kit Campeon, which also matches model 91/92 from 1973.

Whatever, frame is an obvious re-stamp.

 

Edited May 9, 20197 yr by lorenzo

I never recall a 198/199 engine with springs holding the exhaust on to a manifold, which the Barrel on this engine appears to have. So I presume it's a 159 Barrel or earlier.

It's just an earlier manifold from a 158 to take the M92 pipe as the early 325 and later 250 are the same fitting