POMEROYS RACE WINNING BULTACO

[JC]

This is good healthy debate IMHO Geoff. As I've said elsewhere on this forum I'm a great believer in that famous statemant, "Men are never more likely to settle a matter rightly as when they are allowed to discuss it freely"

And here's the bike that was claimed to be: "CHAMPION BULTACO 250: MX frame made in 74"
But the evidence it seems indicates otherwise, ie a CMS

That looks everybit a CMS to me judging by the look of the swingarm pivot, the length of the head gusset coming down the front tube and the swingarm gussets.
Tried to look closer at the snail cams but I can't zoom in clearly with that size image
Where was it quoted as being a Champion? And when, back in the day or recently?
Show me another Champion frame that looks similar and I will reconsider my view.

Yes Geoff, thats what I'm saying. The claim is that its a Champion, but the evidence is that its a CMS. I'm going w that.

The bike was advertised in Old Bike Journal #76, 12/96 & also featured in La Voz de SMOG #35 10/96

Don’t know about this Shwerma thing you keep mentioning.
He has made no claim to Jims frame

He wouldn't have made any claims if it was a factory built frame, which for me on the evidence is the most likely scenario.

you haven’t shown that he has made any frame so close to stock that it’s hard to tell the difference, which seems to be the case for Jims bike.

With respect Geoff, neither have you. There are no pics of CMS frames in 73 & the pics of later CMS frames are noticeably diff to pursang frames of 73.

What I have shown previously is Schwerma frames for the Mk4 pursang in 70-71 that are very very similar to the pursang frame of that era, incl the very distinctive rear subframe & the top-shock mounts that I've not seen on any other manufacturers OEM frame or aftermarket frame except Schwerma's pursang ones.  (ie the rear uprights extending above the horizontal seat tubes then bending horizontal for the shock mounts). It takes a fairly observant eye to see there are some diffs in the engine cradle & bot front engine mount of the Schwerma frame to the pursang one.



The later Astro frames are very similar to these Schwerma ones too, including that engine cradle - yet another Schwerma-Bul link.

And in another bit of relevant info I've just found, JP states in 2006: "While riding a custom-built 250 Bul Pursang at age 18 I completed in my 1st professional US 250 class MX race... at Puyallup". That is confirmed on the legends website as the last round of the 1970 TransAMA - exactly when Schwerma said he was involved w providing the Bul riders frames, for which I've posted evidence above (Tom Rapps M68).

Thats plenty of links between Schwerma & Bul, but nothing conclusive for for providing JP's 73 GP frame. Just as there is nothing conclusive about CMS providing it.

Having pawed more over the factory frame I posted earlier (B100248) & Bul fabrication of the era, I've found more evidence indicating to me that its a factory frame, which I'll put in another post.

[vmx42]

"Men are never more likely to settle a matter rightly as when they are allowed to discuss it freely"

…boy that is a bit deep for a discussion about a 30 year old motorcycle. 

[JC]

I've preveiously noted the distinctive Mk5-6 pursang seat brackets (but can't find a pic that scans w clear enough detail). Later pursang brackets were same shape but pressed steel, instead of having a small gusset welded perpendicular to the bracket.

Neither the CMS or Schwerma frames are anything like it, as you can see if you compare them.

The rear subframe/top-shock-mounts are classic pursang, which I've never seen on any CMS frame.

The headstock gusset shape incl the distinctive slot for a weld to the downtube close to the headstock exactly images Mk5&6 pursangs (Mk7 & later were diff). The late 74 CMS frame has that welded slot too, but again, which came 1st? Bul were doing it 70-71.

Altho pursangs used single plates for the s'arm pivot, from Mk4 M6801885 onwards (Nov 1970) they used boxed in gussets for the footpeg area. Its only a small step from there to box-in the whole pivot area. My guess is that that system is lighter & stronger than a thick plate on ea side but more expensive to fabricate, so some of the works/protoypes frames got the boxed in system but prod'n bikes got the cheaper thick single plates.


Those are all examples of a fabricators signature techniques that you (rightly) argued for before, Geoff, & any Pursang tragic should be able to confirm them.

So for me, the most likely scenario for JPs 73 Spanish GP frame, in order of preference/liklihood is:

1) Factory built prototype lightweight frame
2) Schwerma built frame
3) CMS frame

Each are entitled to their own conclusions.

[huskibul]

    Good stuff ! nothing like a good mystery   for me confirmation from colleague's / family or friends looks good at the moment all great info but too many if's but's and maybe's !  cheers

[JC]

Too true!

But in the absence of any conclusive evidence or definitve knowledge we've put on our best Sherlock caps & are trying to solve the mystery.

Got any contributions?

[huskibul]

   Not at the moment !other than the picture showing the shockmount/loop on gp bike looking very factory,anybody got any contacts in the good'ol US? 

[TooFastTim]

At the time Bultaco was tied into a Spanish Government controlled European Common Market deal to buy steel from Russia and other eastern block coutries in exchange for supplying tooling and expertise for supersceded Fiat cars to be made in Russia.

Shit Firko do you realise the magnitude of that statement? I'm not doubting the voracity of it just that it's historical implications are profound.

Franco loathed communist with a passion. He made McCarthy look like a kindergarden teacher. Such is realpolitik I suppose.

A few years ago I heard a story that made me re-evaluate the whole apartheid regime being equally anti-communist. Story goes that, after the fall of the "wall", a high ranking SA air force officer was touring a Russian jet engine manufacturing facility. He was greeted with warmth and, obvious, familiarity. "What gives?" asked one of his companions. Apparently the SA air force had been working with the Russkis for years to integrate Russian jet engines into the Mirage III airframe. Even before the collapse of communisim.

Politicians speak with forked tongue.

[JC]

Don’t know about this Shwerma thing you keep mentioning.

The reason is because of the established links between him & the factory/riders indicating he provided Pursang cro-mo frames for them prior to beginning of 73:

claims he did so during 1970 TransAMA
report/claim JP rode a "custom built 250 pursang" in last TransAMA of 1970
photo evidence of Tom Rapps bike 70-71 using Scnwerma frame
photo-evidence showing similarity of his frames to pursang frames of the era
photo evidence of Jim Odoms 71 bike showing Schwerma frame

There are no such connections for CMS

It surely is therefore logical & likely that if JP/Bul wanted to get a US-made frame in late 72/early 73 for the 73 GP season, they would have gotten it from Schwerma.

You seem to be ignoring all that

But of course, there's no conclusive evidence one way or the other for the scource of that 73GP frame. And even if Ron P says that it was a factory frame, Schwerma/Champion frame or CMS frame, that is still only a claim (38 yrs after the event!), not conclusive evidence.


Just re-looking at the CMS frame ads & pics of #42U with CMS frame, its not actually clear whether the CMS Bul frames even have the boxed-in pivot area like B100248 frame, or just double-plated pivot area like CZs & the CMS CZ frames.

[JC]

Mark, if you do get to speak w Ron P, it might be worth asking if he knows/remembers what happened to JPs Spanish GP bike, or his Superbowl 2 bike. (And if they were same/diff bike)

[GMC]

It surely is therefore logical & likely that if JP/Bul wanted to get a US-made frame in late 72/early 73 for the 73 GP season, they would have gotten it from Schwerma.

You seem to be ignoring all that

But of course, there's no conclusive evidence one way or the other for the scource of that 73GP frame. And even if Ron P says that it was a factory frame, Schwerma/Champion frame or CMS frame, that is still only a claim (38 yrs after the event!), not conclusive evidence.


Just re-looking at the CMS frame ads & pics of #42U with CMS frame, its not actually clear whether the CMS Bul frames even have the boxed-in pivot area like B100248 frame, or just double-plated pivot area like CZs & the CMS CZ frames.

No, not ignoring it, its just that Schwerma wasn’t the only guy making frames in Ca. in the 70’s and there is no claim that I’m aware of that he made a frame for JP in 73.
There is however a comment relating to CMS & the 73 GP which I don’t think we should rule out altogether.

Also, the story as I understood it was that JP didn’t go to Europe to race the GPs in 73, it just happened while he was there. If it was planned then Bultaco would probably not have let him use another frame.

I’ve been wondering why you have been calling the swingarm pivot area “boxed in”
Typically the CMS frames are 2 plates about 25mm apart strengthened by connecting tubes. The top tube being the swingarm pivot, the lower tube is for the footpeg mount and the middle tube is for the brake pedal pivot. This is how the CMS-CZ frame is anyway. You can just make it out in the add pictures and this is my only close up – a cad drawing from my files.



The angle of the ‘42U’ picture doesn’t let us see but the ad pictures show it as 2 plates.
Have also been trying to look close at the ‘works” frame JC put up but it’s hard to make out in low resolution.

The other interesting thing is the head gussets and the welded slot into the down tube

From one of my CMS-CZ frames


From JC’s picture from Hugh’s Bultaco


This is what I would call typical of CMS frames, are you saying that standard Bultaco frames used it too?


The engine cradle of the CMS - Bultaco frame and the Hugh’s Bultaco frame looks very similar also

From CMS ad



From Hugh’s Bultaco



This only begs the chicken / egg question….
Did CMS copy a Works Bultaco frame?
Or
Did Bultaco copy a CMS frame?

Also what makes a frame a works frame….
Is it a special frame supplied from Bultaco?
Or
Any frame that a sponsored Bultaco rider used?


Can you enlighten us on the significance of Hugh’s Bultaco JC?

So far all we’ve really achieved is to hijack Jerry’s thread and raise more questions than answers.

[huskibul]

    My 72-73 ' mk5 has the welded slots in gusset,also straight headtube with tapered bearings ?

[JC]

I’ve been wondering why you have been calling the swingarm pivot area “boxed in”

Yes Geoff I know the CMS CZ frame is double-plated at the pivot just as you describe.  But I've been referring to what the "factory frame" (# B100248 from Hugh's Bultaco - pics above) has as boxed-in. ie on the front side of the double plates it has another plate between the 2 plates, perpendicular to them & joining them (so dirt can't get in; to brace/strengthen it etc).


I tho't it was obvious on the pics posted above of that frame. Its certainly quite obvious on the original (which anyone can check if they have the book)

I tho't the CMS Bul frame in the CMS ad & on bike #42U had that same boxed-in pivot area, ie was not just double-plated but boxed-in, which I had tho't was a possible similarity/link between the "factory frame" & CMS  - signature fabrication/craftsmanship etc. But of course I now know its not

As I said in my last post above, on further checking the pics closely this morning, I see its not clear that any CMS frame has it. Not only have you confirmed that they don't, & that they only use double-plating, but I also just found evidence from #42U rebuild that his CMS frame is not boxed-in but is double-plated

The other interesting thing is the head gussets and the welded slot into the down tube


This is what I would call typical of CMS frames, are you saying that standard Bultaco frames used it too?


The engine cradle of the CMS - Bultaco frame and the Hugh’s Bultaco frame looks very similar also

Yes Geoff, thats exactly what I'm saying above on both counts.

The engine cradle is exactly the same as all pursangs back to Mk3 (from 68/69). The slotted gusset is exactly the same as Mk5 & 6 pursangs (72 & 72) but I can't scan a pic w clear enough detail to show it. Its one of the distictive details about that frame that ties it to 72-73 for me.

My 72-73 ' mk5 has the welded slots in gusset,also straight headtube with tapered bearings

Thanks Huskibul. (I'd think the tapered brgs would be aftermarket but I could be wrong. Mk7s & 8s had them)

This only begs the chicken / egg question….
Did CMS copy a Works Bultaco frame?
Or
Did Bultaco copy a CMS frame?

Exactly what I was thinking a couple of days ago. But since there's no evidence of CMS Bul frames prior to Nov/Dec 74 & plenty of evidence of the features on prod'n pursang frames looong before that I've had to conclude that CMS copied Bultaco, just like they did w their CZ-copy frames.

Also what makes a frame a works frame….
Is it a special frame supplied from Bultaco?
Or
Any frame that a sponsored Bultaco rider used?

In this case (frame B100248) "It is a genuine factory racing frame used by Bultaco sponsored riders while racing in the US".  I quoted that above, quite a few posts ago.

Can you enlighten us on the significance of Hugh’s Bultaco JC

Hugh's is the most pre-eminent Bultaco place in the US & perhaps the world. He was a rider & dealer (IIRC) back in the day, has barnfuls of Buls now (literally), & is also the custodian of many Bul treasures of historical significance. He is regarded as a real authority on Bultacos & was very friendly/familiar w JP when he was stil alive

So far all we’ve really achieved is to hijack Jerry’s thread and raise more questions than answers

I'd have tho't it'd be helpful to Jerry for building his replica. Apologies Jerry if it ain't.

[jerry]

No apologies required guys. I'm loving it!!. When and if we all agree on the frame then the problem may be chasing one down! Did I mention that the one I have in my garage looks like it could be a "factory" frame! Cheers Jerry.

[JC]

Photos please!

[Swiss]

I saw this bike in person at the University Honda/Bultaco dealer in Seattle, WA in the mid-'70s when I was building my Honda XL350.  They were the local sponsor for Jimmy Pomeroy and their Engineer/Builder was named Al Oppie.  He did center port cylinder head mods to the early XL350 heads before the factory built them that way and that is how I met him.  Really nice guy, used to build Offenhauser-Indy race engines.  A few years later he went into a partnership with Bob Braverman (former magazine writer/publisher) building high performance Ducati bikes in Southern California.  They called their shop Powerhouse Performance and built the Ducatis with big 44mm Mikuni conversions.  They also built custom Honda XL350/403cc engines with lots of trick parts and the same 44mm Mikuni carbs.  One magazine drag raced one of their XL403 bikes against a Kawasaki 900Z1 and the little Honda stayed in front through the 1/8th mile where the power and gearing of the Kaw Z1 pulled out in front.
Just thought I would add a bit on the Optaco and Jimmy's sponsor.