I picked up a spare "parts bike" 348 last week.

I'm trying to figure out the date of manufacture by the number stamped on the engine, but, the problem is, there is no 51M number [ or any markings here ] stamped on the case below the carb bowl, instead, the only numbers I can find on it are "1313" stamped on the cases at the rear mount / bolt boss. Otherwise, it sure LOOKS like a 348 engine.......

Thoughts?

If it has the wavy finned head, 6 speed box and frame tubes under the engine it may well be a 348. Check the frame number on the headstock as the 1313 are case numbers eg 13 is l/h and 13 is r/h and should have the same number as they would have been machined together

Dave

Hey Dave, Thanks for the reply.

The headstock number is 51M 0010 Perhaps this is a very early 348?

The engine sure looks identical to the other 348 I have.........

Thanks for clearing up significance of the numbers stamped n the case halves on the rear mount boss.

That is an early one, the engine numbers on my 247 are on the top of the front engine mount in front of the cylinder

Dave

It IS a very early 348, the tenth in fact. Does it show signs of being beaten? It may be a works bike...

It IS a very early 348, the tenth in fact. Does it show signs of being beaten? It may be a works bike...

It is well used........ I bought in in a non-running condition. The previous owner was going to repair and ride it, but had too many projects on the go, so selling it to me. Has good fat spark and good cyl compression. Forks appear bent / misaligned. Tank has been repaired and repainted, but is still rough. Torn seat. Fenders are not original. I haven't had a chance to try to run it, as I too have another 348 project on the go.

What is a " works bike"?

Edited March 19, 200917 yr by Spokerider

All manufacturers of trials bikes developed their machines by having works riders (ie riders who worked for the companies and got paid good money, who competed in events and gave advice on changes needed to be made to make the bikes more competetive) From the engine number you have provided, I tend to agree with Vintage Cota that you may be the new owner of one of those bikes. You lucky man!!!

riders who worked for the companies and got paid good money

So that's what a "works" rider is......

Seems strange how a bike of this vintage has found it's way into BC Canada......... as odd as it is, it's kinda neat having it.

Edited March 19, 200917 yr by Spokerider

I picked up a spare "parts bike" 348 last week.

I'm trying to figure out the date of manufacture by the number stamped on the engine, but, the problem is, there is no 51M number [ or any markings here ] stamped on the case below the carb bowl, instead, the only numbers I can find on it are "1313" stamped on the cases at the rear mount / bolt boss. Otherwise, it sure LOOKS like a 348 engine.......

Thoughts?

Can you post a picture, please? I think I can help confirm its identity. Your bike is a very early one. While it is true that sometimes factories reserved early production numbers for works bikes and prototypes I don't think that's the case here. I was working at the factory during those days and got a bike from the early production run ( #51M 00011) if my failing memory serves me right. They built 25 bikes just before the Spanish World round for sponsored riders. They were early production models built on the assembly line and not works bikes. There were many differences between the works and pre-production bike and production.I may be wrong, but being able to see a picture would help me confirm it.

Cheers, Martin Belair

When I get a chance, I'll take some pics and post them up. I'm certainly interested in learning more about it!

Its a Malcolm Rathmell rep model, just like my one , i will have to check out my frame number

Dave

Thanks for posting the pics. It's a production model and not a works bike. It is a very early number and I agree that it is strange that it found its way to Canada.

Check the welds at the point where the 2 frame tubes come up from the engine and meet the steering tube. They were known to crack there. Later models had a triangular gussett plate welded in there. I will try and post a picture.

Also, the tranmissions on some of the early ones had lots of neutrals. Re-shimming the trans was the cure.

Keep the chain well adjusted because hitting a big step with a loose chain will actually cause the front c/s sprocket to skip a tooth and it make a hell of a noise. Later models had a case guard installed to avoid this. I think the also moved the sing arm pivot point.

Also check the inside the rear hub for cracks around the bearing. Later models had more webbing.

The forks may NOT be bent or mis-aligned. Older Montesa have stuck forks often. The bushing on the damper rod swells up (dissimilar metals reaction) and cause the damper rod to stick in the forks tube. When you take the forks apart you can pound it (damper rod) out with a broom stick, be careful.

It looks like the rear shocks mat be silver Betors. They were a common upgrade from the standard Telescos. Keep them if they still work well.

You have a bit a work to do but the bike is well worth saving and while it is not #1, low numbers always help in a vintage bikes' value.

Where are you getting you parts? Steve Odell in BC or Jed Bates in AZ?

Good Luck, Martin Belair

My frame no is a lot higher 51m 7997 and it has the welded gussets

Dave