max

Hi, Apologies for resurrecting a very old thread, but i have just rebuilt my Pursang engine and when starting the engine the kickstart ratchet was not disengaging, so constantly chattered. The thread above was very helpful and clarified what my issue was, as i missed the reference in the manual to rotating the kickstart shaft to set the shaft spring tension. Very time consuming error on my part!! I have stripped the engine down and again and have now tensioned the shaft spring. Can i check if this is the correct position of the inner ratchet and the spring tension? I want to be sure before i put it all back together and back in the frame. Thanks very much in advance. Max Thanks for confirming Lorenzo. The chamfered hole on the shaft is indeed at 9 o'clock in its 'resting' position, so fitting the external return spring should be OK. (although a frustrating exercise) The crack looks a lot worse in the close up pics than it does in real life. It is not visible on the underside of the case, more an indentation, so think i am OK to live with it for now. Might well regret that though. Thanks again, Max

Hi, Apologies for resurrecting a very old thread, but i have just rebuilt my Pursang engine and when starting the engine the kickstart ratchet was not disengaging, so constantly chattered. The thread above was very helpful and clarified what my issue was, as i missed the reference in the manual to rotating the kickstart shaft to set the shaft spring tension. Very time consuming error on my part!! I have stripped the engine down and again and have now tensioned the shaft spring. Can i check if this is the correct position of the inner ratchet and the spring tension? I want to be sure before i put it all back together and back in the frame. Thanks very much in advance. Max

Thanks Lorenzo. If anyone else knows anything about the 173 'Trans Track' reference that would be great. Thanks, Max

Please excuse the odd copy at the bottom of my message, won't let me delete it.

Hi all, I have just purchased a bit of a bitsa Bultaco Pursang that i am going to restore. The motor in it is a 173 prefix (JM-17300036) and when i search on the Cemoto reference page it comes up as a 'MOTOR TRANS TRACK 350'. https://cemoto.tripod.com/bultaco.htm Can anyone tell me more about this motor - as in what model it was built for, what the JM stands for and why the slightly odd non-model specific referenece? Thanks, Max

Thanks Bondy - I'll give that a go. Cheers, Max

Hi guys, Can someone please remind me the standard settings - pilot jet / mixture screw AND idle / throttle stop screw - for the Amal carb on a 250cc model 150 sherpa It is on standard jets. Thanks very much. Max

+1 on the blast, wash, dry paint process. Also, PJ1 paint does not need to be heat cured - it cures to a durable finish overnight. Cheers, Max

Hola! That looks great too. Is that a Sammy Miller pipe? Do you have a contact for the alloy mud guards? Cheers, Max

I will do - i just need to get over the paranoia of scratching it for the first time!! The tank took me 2 blooming weeks of prep and paint alone!

Thanks very much for the kind comments. The fenders were plastic, not alloy, for the 1975 model 150 that this is. I have photo's of the bike as it left the dealer. The filler cap on the UK spec 'Homerlite' tank is also original and as it was produced in the UK. This bike was so original before i started the strip down that every single bolt was still the original Bultaco stamped items. I have moved the speedo to the centre of the handle bars - The Renthal bars with the brace make it s very tight fit, but it is now OK. The only mod is the new improved Bultaco UK electronic ignition from Dave Renham. Apart from that every part (excluding rubber parts, gaskets etc) is original. I plan to road register and MOT the bike, so i can go for a blasts on sunny afternoons and play around. I have more modern Beta Zero and GasGas TXT to play on in the mud and also sportsbikes (GSXR 1000 road bike and GSXR 750 track bike) that keep me very busy. I'm sorry to say this one may be a bit of a garage queen, for now anyway! Cheers, Max

Hi all, Just thought I'd share some before and after images of my Sherpa project bike i have been slowly bringing back to better than new condition. Everything has been restored , re-finished or rebuilt - including all frame parts, cycle parts and engine. It now has electronic ignition too which is great. Apart from the powder coat and re-chrome it has all been done with my very novice hands, and has been a bit of a labour of love! The bike was my fathers from nearly new and has covered under 300 miles, so was ripe for a resto job. The first photos show the condition it was in when i dragged it out from the back of the garage and the latter photos show it as it is now. I'm very happy with the result, let me know what you think. Cheers, Max

Any flexible/silicone based oil resistant gasket sealant should be fine - e.g. Loctite or Hylomar Bigger question is why is is leaking in the first place? Can you not see the affected area? Have you tried gently sanding surfaces with wet&dry by sticking wet&dry to PERFECTLY FLAT surface (bench or table top) and gently sanding the mating surface on it? Also inspect the engine casing side closely for any burrs or left over pieces of gasket that could be causing the leak.

I've not had much luck with finding people to reline the hubs apart from Bultaco UK's contact. Exchange steel lined (not chrome as original) hubs are

Hi Andy, I am just about to tackle the same job, so all very useful info. Can i check, did you remove each full leg (stantion and fork bottom) from the yokes, or can you remove the fork bottoms with the stantion still in place to change the seals? Thanks, Max

Thanks for all your replies guys. Today I removed the carb, blew through all jets with the compressor (again), inspected the throttle body and slide (which both looked fine), re-fitted and re-set the pilot screw (fully in and 1.5 turns out). I kicked it over, blipped the throttle a few times and it returned to idle fine - nice and quick and nice and clean. My guess is that it was a partially blocked pilot, hence the slow return to idle, but i am just glad it is running properly again. Thanks all for your input. Max PS - it seems PJ1 (Satin Engine Case Paint, not their exhaust paint) is the best paint for bully exhausts, if you don't have the facility for high temp curing!

Hi Tom, Not doing bad thanks mate... apart from a frustrating day in the garage. One step forward and all that... How are you - have you re-claimed your garage yet? I would definitely give powder coating a go, but am trying to stay as close to original as possible. I think my issue is not letting the VHT paint cure/bake on the bike? I'll re-paint and keep my fingers crossed. Cheers, Max

Hi Woody, It is still running the original Amal carb. The bike has only done a genuine 187 miles would you believe (it has been my fathers since new) I am thinking it may well be the carb/slide body. Would it help to give the slide a light rub with 1400 (or higher) grit wet and dry to make sure it is as smooth as can be, do you think? Or is there anything you can use to lubricate the motion slightly? I am happy to buy a new slide, but wonder if it is worth trying anything first? AND any suggestions or tips for VHT paint for exhaust? Thanks all. Max

Jetting is standard and this problem was not apparent before the engine strip and rebuild. Somehow, it doesn't feel like a jetting problem.

Hi Zarkoff, Yes i checked that by spraying a little easy start around the manifold/carb/airbox and the revs were not affected. I normally use this trick as the the revs should rise if there is an air leak. The manifold is on pretty tight from carb to manifold and manifold to head. Any other way of checking if air is getting? Cheers, Max

Hi all, I wonder if you could help me with my 2 questions below... 1) I am currently finishing the full restoration of a model 150 Sherpa T 250 and got the engine running today after installing the (new style) electronic ignition from Dave at Bultaco UK. The bike starts, idles, revs and runs really nicely - the problem is that when i blip the throttle the revs don't drop back to idle as quickly as i would expect. After each blip, the revs drop gradually, slowly settling back to normal idle - it may only take 1-2 seconds, but it doesn't seem quite right to me. - I have had the engine fully re-built by the guys at Bultaco UK, so it should all be sound - The throttle seems to snap back fast enough so it doesn't seem like it is an issue with the throttle - The throttle slide/carb body seems in good nick visually - I have checked there is no air leak at the carb/airbox Has anyone experienced anything similar or can anyone suggest anything? Throttle cable needing lubing perhaps? 2) What VHT paint do people use to paint exhausts? In my experience exhaust paints can be a bit rubbish and chip/scratch with the slightest touch or knock OR ruin the finish with a drop of petrol or oil? Any tips/advice for how to paint an exhaust that looks nice and lasts more than one outing would be great? Many thanks in advance, Max

I usually tape/zip tie it to the head steady, so it is out of the way.

Hi Tom, I will definitely give it an outing when it is done. I am waiting for my re-chromed stantions to arrive this week and then my wheel hubs to be re-lined and wheels re-built by Bultaco UK's wheel building contact for about