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One of the old pictures wouldn't fit in the last post, and it's the one I think is the coolest with all the bikes! I also saw a gentleman selling repop signs on Etsy and purchased one for the shop wall

While going thru pictures I found quite a few cool ones of the Bultaco and various trips he had went on. With the rough cleanup done I decided that I would work on the bike once I wrapped up another project I was currently working on. I would never repaint it as it is in such nice original shape, however I would tear it down and go through everything from top to bottom to make sure it was riding ready and use it as a little toy in my wood lot The bike sat quietly under a sheet until fall of 2025, with it being uncovered to show many people throughout the year and quite a few kids taking pictures with it at various gatherings

Hi everyone, I posted in the welcome area but thought I would start getting this thread caught up to where I am currently at on my restoration of my Bultaco Sherpa T 250. I have done many other restoration projects but this is my first motorcycle project The bike was originally purchased by my late Uncle Bud on August 21, 1970 (I have the original bill) and he used it mostly as a hunting bike as he had other bikes he used in trials riding. Fast forward to while I was in high-school it turned out my science teacher was the son of the Bultaco dealer for our area and knew my Uncle well From what my Dad told me Uncle Bud was 2nd or 3rd best in all of Ontario in numerous championships at the time. Time passed and the bike sat since I believe the 1980s. At the end of 2018/early 2019 Uncle Bud gave me the bike before he got sick, and I always told him one day I would fix it up. At that time I was 21 years old and in college and didn't have the funds or time to embark on fixing it. Due to his illness Uncle Bud's memory faded and I had his tired bike in the corner as I took car of his property/small farm and said I would fix it up. He ended up passing away in October of 2024, I left work that day and went to reflect out in the shop, and knowing that his celebration of life would be hosted within the next few days I rolled the Bultaco out and spent hours detailing it to surprise both my parents and our family I am still trying to learn the process of this forum so I hope I added the "barn find" pictures correctly And this is ready for the celebration of life

Hi all does anyone know what size the bolts are please on a rev 3 270 2003 . Cheers

Thank you! They really are nice looking, I enjoy seeing other people's all cleaned up as it gives me inspiration. I've read a lot of bultaco threads on here already

Excellent. Model 49s are a wonderful looking bike.

The motorcycle frame and engine casings are the earth/ground for the motorcycle. Most people ground their kill switch at the HT ignition coil mount.

Did anyone find any good options for these flex force replacement straps? I need one. Is there any way to have them made? It seems like there is a bit of demand for these still

I’m have a similar situation. It appears my black wire is not grounded unless it is grounded in the head light. Is there a spot on the frame that it is supposed to be grounded?

Hi everyone, I'm new here from southwestern Ontario, Canada! I found the site as I've been restoring a Bultaco M49 Sherpa T that was left to me by my late Uncle I've done many restorations on other things (tractors, lawn equipment, radios and arcade equipment to name a few) but this is my first bike project. I have been given a lot of good information from Facebook groups but I always enjoy making a forum thread so I plan to document my project here, hopefully in the future my info may help someone else 😊. Mikey.

Can only buy the correct plug as a Honda replacement part in Canada and Honda dealers don't sell that bike here now 😐 NGK does not import it here. Parts are very expensive when your closest supplier is 2000km away and almost nobody owns one 😎 but if price is no object they sure do work good.

I feel your pain. They can be pricy from trials shops. I believe the same CR6EH-9 plug is used in small Honda and Yamaha outboard motors so a boat shop is another option. We can buy that plug for around AU$11 at the local car parts stores. Even cheaper online (except for the postage).

👍 Even more wily Now if they can just sell the spark plugs for under 20$ 👍

Yup - for the first 0.5 of a second. Then "normal" non-wasted after that.

So Wasted it is 😎

Hi Everyone, can anyone point me in the right direction to get a new plastics set for the old (2011ish) Oset 16? I’m really struggling to find anything at all. Uk or European based ideally.

Hi jrsunt Here is an explanation of this picoscope recording, which is just a simple compression test - where I measure pressure/vacuum over a period of 720 degrees, and at the same time I also measure the ignition voltage on the spark plug. The compression test is done with the kick starter on - so the engine is not running. The fact that the engine is not running causes the RPM to fluctuate a lot during the valve timing measurement, and therefore the measurement is not as accurate as if it were a multi-cylinder engine - where the RPM is much more stable - this is actually the same as aussiechris has explained in previous answers. But as aussiechris writes - it can be used as a guideline regarding valve timing.

I was told they were made for Pete but don't know who by. Last I heard was Pete was not well. I have 2 of these clutches work very well.

Honda_freak can answer you better but I believe the red line on both his captures is cylinder pressure. In the most recent pic, the blue line is the fuel injector voltage. In his earlier image, the blue line was the ignition coil secondary voltage. He is showing the relationship between those voltages and the crank position based on cylinder compression pressure. It's not easy to directly correlate time on the x-axis with degrees of crank rotation because during kick starting, the RPM is varying. But it gives a good idea of what stroke it's on and roughly where in the stroke these events occur.

Wish I understood the data, I have no idea what the red or blue lines indicate 🤣( X axis crank degrees and time? Y axis voltage?) That was from my 250 manual. Looks like Honda freak was also been testing the 250.

It doesn't have much bearing on what we've been discussing but it does show that these engines have a very short overlap (just 7° in your case). But thanks for posting it. I'm guessing the cam profiles changed slightly over the years/models. These are the figures from my 2022 301RR... 14° of overlap in this case.

Does this have any relevance to anyone’s data: Intake valve opens 6 degrees before TDC Intake valve closes 27 degrees after BDC Exhaust valve opens 30 degrees before BDC Exhaust valve closes 1 degree after TDC

Hi Chris These are really good oscilloscope captures you have recorded here and will certainly benefit people when they have an ignition-related problem. I myself am also a little surprised at how it goes from wasted spark to non-wasted spark in such a short time horizon - I would not have believed this if it were not for your fine evidence here. I also find your note regarding an injection timing in the combustion stroke just after TDC a bit strange. But I can also confirm that this matches my captures of injection timing in the compression stroke TDC and which occurs 25 degrees after TDC. This is very important evidence of when and how the ignition system works on a Honda Montesa 4RT and other motorcycles / scooters with similar battery-less systems. It seems that there are quite a few secrets that need to be discovered. Just keep up the good work. Regards Honda Freak

It appears to be that the 4rt was the first bike with batteryless fuel injection and the test bed for everything else. With regards to your tests and findings, why is the high tick over so critical for the starting procedure?

These diagrams are drawings I did to explain a fault on my 2008. They are not going to be relevant to other years and configurations so be careful. All the Beta owners manuals including wiring diagrams from 2006 and up are available on-line from the US, UK importers. Anything earlier is tough to find as it will have to be scanned from written owners manuals.