Jump to content


Site Supporter
  • Posts

  • Joined

Everything posted by lorenzo
  1. Looks like Bultaco, but model ?, can't be sure.... Need to see other side of hub.
  2. In a d.c. (battery and coil) ignition system indeed it would......... Unfortunately, a flywheel mag. ignition doesn't work like that - for the reasons already stated. The buzz box is NOT just the same as using a multimeter, as the bleep or buzz will continue to sound, but change note - the whole reason for using it is that when the contacts start to open there is still a complete circuit. - look at the circuit schematic again, in particular the ignition coil. You will see that there are two coils (l.t. and h.t.) either side of the core. That's quite correct..............But that's not what a buzzbox does. We are not testing resistance or points condition, but indicating a change in resistance in the circuit when the points open. That's your reasoning, but once again you are describing the operation of a d.c. (battery and coil) ignition. I'd love to be clever enough to claim it as my reasoning - I'm not.........and it isn't. If you don't believe an a.c.mag. flywheel ignition system could possibly work you have failed to grasp the basic principles. I admit I struggled with it myself before getting my own buzz box I'm rapidly running out of ideas to convince you........
  3. Mike - Any progress ? Did you visit the "buzzbox" site ? I just turned up this:- , which may well explain better what I was trying to convey in my last post. You are of course free to ignore any of the above and/or form your own opinion and act accordingly - it's your bike,etc........
  4. Mike - The reason you are having to remove the c/b. points wires to show when the points open is because you are using a continuity meter/ohm meter. In a flywheel magneto such as you have the condenser and h.t. coil are connected in parallel to the l.t. coil windings, which means that regardless of whether the contacts are open or closed, you will still have continuity. (Effectively, the contacts are always grounded........) This advice would apply to coil and battery (D.C.) ignition NOT flywheel magneto (A.C.) ignition in discussion here. Clearly, no it doesn't...... To time your magneto the accepted method is to use a timing "Buzz Box" which will indicate when the points open using a change in resistance, rather than an actual break in continuity. Additionally, if you are using a d.t.i. or timing stick/plunger in the spark plug hole, it's an awful lot easier to hear the opening point than trying to watch the flywheel/contact points/piston position indication, etc. all at the same time ! Here's a link that you may find helpful : http://www.dansmc.com/buzzbox.htm HTH - let us know how you get on.
  5. For the unconvinced :- There you go............. Picture page 40 of Don Morley's "Spanish Trials Bikes" ISBN 0-85045-663-0 (pub. Osprey Publishing Ltd. 1988)
  6. Miller frame above was the most recent pic. I could find (1978) in any of his catalogue material in my possession. Just looked at my copy of "Spanish Trials Bikes" for the first time in years and yes, I agree with your opinion entirely. Mystery solved, and well done Stuart, I'd say.
  7. Aren't you comparing apples with oranges ? Looks very much like one to me.....albeit modified around the rear loop. November 1978 price :- £120.00 + VAT (at 8% !!) p.&p. £2.00 - Makes you think, doesn't it ? Hope this helps.
  8. Ciaran - The info. you want (I think) was covered in an earlier topic listing. "199a running refurb. - new member cosmo" on Aug. 8th. last. Sorry, tried to create link but lack i.t. skills........ HTH
  9. Hi - I have a 1960 (road) Bullet - a long-term project for which I have struggled to find correct front fork parts......I am reliably informed theyv'e all been snapped up by the pre-65 Trialers ! Your chances of finding a complete and correct, ready-to-use gearbox assy. (or one in any sort of condition, come to that), I would estimate at zero or less - but what do I know..? First port-of-call for anything Royal Enfield has to be Hitchcock's Motorcycles Ltd., although I suspect you already know this. A picture speaks a 1000 words, it's said - any chance of seeing your bike and/or the present gearbox ?
  10. Gentlemen - if we can get back to the original post, please..........! The point I attempted to make in my response is that any alloy rim will corrode if neglected. However, I think in the case of DC's bike I would be very disappointed to find that level of corrosion in just 5 years, particularly to a tubeless rim. (My understanding of these is that they should be particularly well-sealed against such deterioration, with the inflation valve the only weakness - or maybe I have that wrong.) I should point out that the Bulto/Akront tubed rim in my pic. had worn its tyre undisturbed since 30 years ago, (when I bought the bike as a non-runner) and possibly up to 34 years (when the tyre was new) - and of course has many more holes to allow the ingress of moisture than a tubeless ........
  11. Soap is by its very nature CAUSTIC. Oxford dictionary defines soap as "a cleaning agent that is a compound of fatty acid", etc. Proper tyre soap is NOT soap - more accurately tyre LUBE. I am quite familiar with corrosion to rims - here's what I found on removing the rear tyre from my Bultaco Alpina long-term project :-
  12. Ooh, sorry to hear that, Old man - now I feel your pain.......
  13. Tsk, tsk, Old man - far too touchy. You came here seeking advice - which was freely given. Everyone in this free world is entitled to his own opinion. No need to go off the deep end........ (This is from another old man with lots of Bultacos)
  14. Removing the cylinder base sleeve nuts can often prove a task in itself if a p.o. has used an ill-fitting key and rounded-off the internal hexagons - you have removed all the nuts, haven't you ? (Maybe, not obvious to someone unfamiliar with working on these engines......) Jarring the barrel with a hammer and piece of wood to the exhaust port, or similar usually then does the trick. Do not lever on the cooling fins or any joint face !
  15. My mod. 159 has it - I think it's a standard fitting for a longer seat. My mod. 85 and 92 both have a hole in the underside of the loop (lower side of the tube only) - any thoughts on that, anyone ? (The 85 also has a vertical hole through the centre of the loop but I suspect that's non-standard) Seems if the o.p. asked a silly question, there are plenty of people silly enough to answer it ..............!
  16. To remove spoke cover disc, first remove sprocket. (Apologies if you've already done this).
  17. If it's a Lobito 175, numbers will start M84, B84 .....??
  18. Factory parts manual lists steering lock for mod. 91 ser. no. 00727 onwards, and for mod. 92 ser. no. 02387 onwards. Presumably this denotes the start of the 2nd. series/Mk. 2 as these are also the change points for bottom yoke, etc. (Parts book makes no mention anywhere of Mk.1, Mk.2 referring simply to serial numbers) Homerlite tank/seat unit as offered by Mr. Miller in his 1973 catalogue :-
  19. If you are still using the circlip fixing top and bottom, you also need to pay attention to the i.d. of the eye bushes.....
  20. lorenzo

    Bultaco M80

    Do you really believe if the factory made a prototype they would make it heavier than standard ? No way - much more likely the extra lugs were added by a previous owner for sidecar use. The early frames are very heavy anyway owing to the quality of tubing used. I've heard this referred to as "gas pipe" and the like by knockers, but it was all that was available to the factory at the time.
  21. As others have already pointed out, it's a bitsa. I can see parts from several different models there.........don't let that put you off, as it doesn't make it any less rideable or enjoyable. However, if the serial no. stamped on the frame headstock is the same as the engine it's a re-stamp.......
  22. Without a picture, a crystal ball would probably be more use than keen eyes ! Post the engine and frame nos. and I'm quite sure someone on here will be able to help.
  23. Wilson - What distinguishes this early crank from later ones ? Would it be possible to use a later crank ? Is your engine no. 21M.....followed by earlier/later than serial no. 1079 ? (I have an engine broken with that serial no. - this one had snapped its crankpin.......)
  • Create New...