I assume you are referring to this type :-
of Spanish-made Monobloc and main jet is #30 in the illustration ?
(I have the drawing, but not the corresponding parts list)
I acquired a number of these jets "n.o.s" in various sizes along with some other Bultaco parts I bought many years ago, and at the time was unable to find anyone able or willing to identify them. All appeared to have been supplied originally as official Bultaco parts and were packaged and labelled as such; more irritatingly, they are shown in Clymer manuals in similar pics. of carb. and photo stripdown sequence, etc. - and not mentioned in the text ! .
Bult 360 -
(with apologies for going off-topic a bit)
You don't say which Mk. I Concentric - size ? UK replacement, or Spanish original ?
Depends on how much better you would ride with a lightened wallet...
Yet another case of believing that every new technological development MUST be an improvement ?
Here's a seasoned expert fitting electronic ignition to his Sherpa, in what is described as "a straightforward d.i.y. job which will improve ignition performance and consistency" :-
www.youtube.com/watch?v=sJZNao4l0gU (copy & paste)
....and it took only 14 kicks to get it running !
I had a root through the residue of my 4-spd. stuff and found a 27t. 3rd. gear pinion but I think it's for a model 11. (It has male dogs as opposed to holes).
However, looking through some old Bultaco paperwork, . I found listed :
"Part no. 10.11.004 Description : Gear, Mainshaft 27T (low 3rd.) "
- not what's listed in the parts book, as you've already discovered, but my limited knowledge of Bultaco part numbering suggests to me that this may be what you require (if that's any help at all).
How many teeth are on the mating layshaft pinion ?
+ 1 with Woody regarding spokes, etc. - (butted stainless would be my choice) - it's all down to how much you want to spend........hopefully, the rims and hubs are salvageable.
The stamping looks genuine to me, and the serial no. is just a few digits earlier than my own 340.
Do you know if it's a UK machine i.e. supplied from new, or do you have any history ?
If it's 25mm. choke/bore diameter, I think that means it's a Spanish-made Amal.......
I found this :-
I wish I could have replied earlier; your own posts are invariably knowledgeable and helpful when responding to others in difficulty.
I know you have the matter sorted now, but I may be able to offer further info. re the "odd " old bolts you have, if you are still curious:-
9.5mm. dia. is very close to 3/8" imperial, which means they can't possibly be "1/4" whitworth (or 1/4" anything else for that matter, as this refers to the shank diameter).
If you arrived at that conclusion using a thread gauge - 20 t.p.i.- then I think your bolts/capscrews are actually 3/"8 BSF - ............unless anyone out there knows differently l
(Fettling old Brit. bikes for any length of time soon makes you aware of all these various Imperial standards - on just two bikes in the shed at the moment I have found BSW, BSF, BSC, BA, BSP, UNC, UNF threads - not to mention the odd spurious metric fasteners that shouldn't have been there.....)
Happy days !
Yes, your bike has a standard cylinder head with radial fins, although it looks like a few may have been broken off..........
I don't know where you've been looking for images, but I simply Googled "Model 10 Bultaco" and came up with a numberseveral showing
Here's an example (I hope) :-
http://www.vintagebike.co.uk/pictures/1966-bultaco-sherpa-t-model-10/#.VGzV9zSsUl8 (image #3 shows fin layout clearly)
and this will possibly link to many more.
The matter of threaded yokes must have passed me by until reading your o.p. - ......but there are pics. all over the internet of course to show this feature on late bikes.
My own 340 was just 6 years old when I bought it, but had the 199/199a etc. yokes (bolt and nut clamp). Mind you, it did have the slab-sided alloy tank.
Well, I think I'd be happy too if my Alpina looked anywhere near as nice........
I assume from the style of tank and mudguards fitted, this is a US import ?
Any "E" problems with the tank ?
My UK-sourced M85 has a Homerlite alloy tank/seat unit as per the '74/'75 Sherpa T offering, although I must say I prefer the looks of yours.
Now, if only I could get my hands on one.........
My guards have been replaced long ago by plastic items - not pretty, but the usual practical choice.
I'm sure we'd all love to see some pictures.........
(My model 85 hasn't run in 25+ years)
WD40 is virtually useless as penetrating fluid - save it for Water Displacing duties that it was designed for.
Get yourself some Plus-Gas formula A or similar and give that a try.
Regret, unable to help with the pinion.
Looking at the pic. my immediate thought is that the original frame was probably replaced owing to damage and the number on the replacement was obliterated by grinding and punching it out, possibly to avoid problems with the local registration authority.
I don't think this would be too unusual for a bike used off-road, and I think early Bultaco frames were apparently easily bent as well as being heavy (little more than mild steel "gas pipe", according to a frame-builder I knew).
Re chrome-plating, this would likely cost as much (or even more) than new bars, and original steel bars got bent even before frames, anyway..... unless someone knows differently, of course.
Which gear pinion is damaged - layshaft or mainshaft ?
Number of teeth. or part no. ?
Good luck with the rebuild.
Very pretty looking Sherpa - well done.
However, here's a couple of my observations : front guard looks very tight to the tyre - don't think you'd get very far in mud.
Rear chain looks way too slack.
My own experience has been similar to trailie's :" I've got some really old ones to move with a good soak in plus gas then plenty of heat on the nipple with a blow lamp."
However, as you haven't posted your location, I cannot be sure that "Plus Gas" (penetrating/dismantling fluid) would be available in your area. I'm also unsure about the availabilty of replacement original nipples as I've not bought any for some time. Good luck with yours - HTH.
Fling it at rocks, totalshell ? You're kidding.........don't think there's any chance of that !!
I found some n.o.s. Miller silencers when sorting through my spare parts some while ago and can confirm that these were supplied in at least two different inlet pipe sizes.
Not sure if this helps, but SPE was a Surrey series, and so it's possible it was registered to Comerfords, or at least someone else locally.
However, one of my bikes which was registered to Comerfords for use by a supported rider bears a BGH (London) series mark, although this machine is somewhat more recent.
Unable to advise about the seal holder or "race", but the normal method of fitting crank bearings to either shaft or crankcases is with heat, not pressing..........
+ 1 for Woody's excellent summary of this model's features. The tank/seat unit is a Homelite item; these are prone to cracking between the "seat" part and the rear of the tank itself.
Well done - that's quite a transformation.........
Was going to comment on the original pic. (until I noticed the date of your original post) that the fork sliders had been transposed - but I expect you worked that out anyway.
Enjoy - and let's hope it doesn't live up (down?) to l.o.tu.s - i.e. "lots of trouble, usually serious").
Love the prop. stand, by the way.........
Bondy, f.u.f. - Many thanks for your quick responses.
I have a number of hubs in need of the "treatment", and an engineer acquaintance willing to tackle it.
What's a reasonable price to pay ?
I'd like to find a figure that's fair to both of us - any ideas, you guys ?
Looks like the universal "hack off the lower frame tubes and replace them with an allow bash plate" mindset may have been abandoned ?...............
I believe Mahle was considered the best available in the day; I'm not sufficiently familiar with what others use nowadays to say whether this still applies.
This possibly raises two other questions, though : would a Mahle item be unobtainium?.......or simply unaffordium ?
Suspension spring rates will have more influence on the tendency (or not) of a shock to "bottom out" than its length.........
Very interesting, Harry - would that be "inside information" ?....
And who holds Comerfords records currently ?