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Everything posted by lorenzo
  1. Fabrice - Don't worry about your bad English, it's "parfait" as far as I'm concerned. And that's a very nice looking Alpina............
  2. Tonyd - Numbers indicate Mk. 2 Metralla frame and (later) Astro 250 engine.
  3. feetupfun, your 198 cylinder is stamped 165, possibly ?

    • FOR SALE
    • USED

    Sherpa 199 engine unit with magneto. Generally sound condition with undamaged outer covers. Suitable for overhaul/rebuild. Matching no. frame modified to 199A spec. with alloy bashplate. 199A swing arm. Modified exhaust system with lengthened header pipe. There is a current V5c in my name ; 78 'T' registration means now qualifies for Historic Vehicle status, should you wish to use as a roadgoing machine. Please ask as many questions as you wish. More pics. available if required. Buyer must collect.


  5. lorenzo

    Oil leak

    Ninja - + 1 on woody's comments. If the leak persists, check that the gearbox breather is clear. It's a small hole high up on the left crankcase, just forward of the fixed end of the kickstart spring. If this hole is blocked, some have found that this can cause an oil leak from the gearbox or worsen an existing one, especially when the motor gets hot. (The air inside the gearbox will expand with heat, and it has to go somewhere, I suppose..........) On this 199 engine I've pushed a piece of wire into the breather to make clear its position :- HTH
  6. Would be easier to fit connecting link at rear sprocket.....is the chain in two (or more) pieces ? What's happened to chain on lower run beneath brake arm bracket (bottom r/h. corner of pic) ?
  7. Hi - Yes, it's a Cotton, probably Cavalier model about '69 or '70. Should have a frame no. stamped on headstock, which will help to identify it positively. Here's a similar one I owned back in the day :
  8. Hi - You need to find a way of locking the engine/stopping it turning, Put it in 5th./top gear and apply the rear brake hard while attempting to loosen the locknut. HTH.
  9. The spacer in reality is narrower than it appears on the drawing. The frame bracket provides an ideal "chute" for the spacer to roll down and out (to get lost) when the bolt is withdrawn....... Without the spacer, tightening the bolt will possibly deform the frame bracket and makes the bolt likely to come loose. .......and can give trouble even when all fixings are tight.
  10. When you fit the head steady, make sure that the spacer #138.10 - 119 (no. 39 in the illustration) is in place on the frame fixing bolt , otherwise it will not tighten correctly. This spacer is easily lost.........
  11. lorenzo

    199b manual

    Workshop ? Parts ? Owners ?
  12. Yes. Or a replacement spacer, like this :- https://www.inmotiontrials.com/product/bultaco-sherpa-speedo-replacement-spacer-17mm/
  13. Slowrider - Oil breaker :- https://www.inmotiontrials.com/product/betor-fork-damper-top-tin-oil-breaker-each-136-02-105/ Works as I explained in my last post. Preload spacer :- https://www.inmotiontrials.com/product/front-fork-spring-pre-load-spacers-10mm/ Works as explained by feetupfun. HTH
  14. Slowrider - Holes in the pistons are one part of the booster ports, the other part being the slots in the cylinder liner. You need these if your engine is to perform as Bultaco intended. First o/size Mahle piston :- www.francetrialclassic.com/en/pistons-and-con-rods/4403-bultaco-350-piston-with-clips-pin-and-rings-diam-8525-mm.html The hat shaped sheet metal caps you refer to are oil baffles/deflectors (Bultaco called them "oil breakers") ; AIUI their purpose was to influence the amount of oil coming out the top of the damper tube. You appear to have non-standard dampers, and I can't see how the caps would fit, but who knows ?.
  15. Typical mainshaft wear :- Typical wear to sleeve gear bushes (note the step) :- Hope this helps.
  16. Mark - Based on my experience with these engines, your main area of concern is likely to be the crankshaft assembly and its bearings and seals, and piston and bore, rather than problems with the gearbox. These tend to be reasonably robust, although possible weaknesses are covered in feetupfun's post. Did you use heat when dismantling ? Difficult to see, but from your tenth picture it looks like main bearings are possibly loose on shafts........ Are you in the UK ? Don't worry about being quite young and lacking experience - we all were once !
  17. Homerlite alloy tank/seat unit, standard on models 124/5 and 150/1, etc. supplied in UK. (see front cover of Heinous manual).
  18. Pics. ? Unless they are damaged beyond saving, you may be best off cleaning up the originals. Cracks can be welded. The primary case is usually thick enough to get away with a fair amount of filing/grinding. Failing this, as Bloomfield states it is the same as fitted to various other models. Not so the mag. cover, which is quite thin and fragile in comparison - and probably also the reason that it's in very short supply. (you may be very lucky to find one that's any better than the one you have). It was also used on a smaller range of models - (for Sherpa range, 198/199 A & B models only) HTH
  19. Slowrider - This is a TRIALS bike, and most trials riders would expect well-tucked-away controls, to reduce the possibility of accidental operation or snagging on obstacles. The brake pedal you have appears to be a version of the standard l/h fitting ; the original version of r/h pedal offered by Bultaco was equally tucked away, but unfortunately also provided a less usable brake.(see responses above). For comparison :- The Spanish pedals mentioned are very nice, but you may also want to consider something a bit less eye-watering, price-wise :- https://www.inmotiontrials.com/product/late-sherpa-left-side-foot-brake-pedal/ It's your bike and you do what you like with it, but my personal feeling is that your views may change once you have ridden it a bit. Good luck with whatever you decide.
  20. Gearbox sprocket oil seal (Bultaco part #160-001) 30 x 40 x 7mm. Gearchange shaft seal (Bultaco part #160-004) 14 x 24 x 7mm. These are conventional lipped garter-type seals - should be obtainable from your local bearing/seal supplier.
  21. Leave the bent cylinder fins - any attempt to straighten will likely snap them. No head gasket - spigoted joint.
  22. Hi - I've just measured a new Mahle (Bultaco OEM) piston. Dimensions the same as those quoted by Old Gezzer. I expect you know that standard bore of 198A is 71mm.?
  23. Alpina M85 was available 1971-74. Which of these years / what model is your Sherpa engine ? Factory parts book (later issue) for Sherpa 250 M80 lists M85 frame and also upper/lower yokes (triple clamps) as replacement parts ; I take this to mean they are mutually interchangeable, even if not actually identical.
  24. Frame : Model 100 125 Pursang Mk. 6 Engine Model 68 250 Pursang Mk 4 Many components are shared throughout the 100/101/102/103/104 Pursang range. If it still has original Amal carb. this might provide a clue : 27mm. on the 125, 36mm. on 250. HTH
  25. Hmmmm....... On 5-spd. Sherpas, the early type sleeve gear bushes were replaced from mod. 124 onwards with needle roller bearings and the 20mm. o.d. seal #160-031 and this arrangement continued to the end of production as far as I know.. I've dug out a mod. 124 sleeve gear so you can see what yours should look like: (ignoring the worn sprocket splines) .. As far as counterboring your existing sprocket,goes, it looks to have suffered some significant scoring to its bore. If your new needle roller bearings are to enjoy a worthwhile service life, the bore needs to be very smooth. (see above). To save yourself lots of further grief, you may do well to check off all the other gearbox parts against the parts book; some earlier (or later) parts will interchange and work, many will not. Who knows what mechanical mischief it may have suffered in the last 40-odd years ? HTH
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