section swept

As we’re still in 2018 that’s a question for the future!?? ?

I see your grass is in brilliant condition too, many just like mine??⛈☀️The Bultaco worker that stamped the first letters of your engine number was either drunk or it was their first day operating a hammer?

Yes because the closer to tdc the piston travels the more likely it is to go staight back down the way it came...backwards rotation.?

Isn’t that white tank an aluminium, looks very like it to me...weld seams etc. The Gripper looks like an alloy one two, last one I had anything to do with had exactly that.

Me to as I said, miles from any where and a dead ignition is not funny but with CB ignition at least you stand a chance of sorting it....until it starts to get dark and you haven’t got a torch??

Well my M80 frame doesn’t have any other markings or lugs. Could this have been a special order for a sidecar adapted bike.? The tank unit would fit if the necessary holes had been made in the sides of seat base/cover panels, assuming it used the original Kit Campione unit. They could also have been to securely locate tools and spares for something like the SSDT. Still think it was modded to accept a sidecar, smaller lug may have been for a passenger grab handle. Now all we need is a Bultaco sidecar expert and the murder ...I mean mystery will be solved???

Is that Don Smith, top left with the sideburns?

The closer the timing to top dead centre the more likely the engine is to start and run backwards. Advancing the ignition point to say 4mm before top dead centre ( occurring earlier) reduces or eliminated this. Retard ( move ignition point closer to top dead centre and there is a more noticeable kick back and a likelihood of the engine running in reverse. Petrol burns at the same rate irrespective of piston and crankshaft speed/ revolutions so starting the burning ( ignition ) sooner before the piston reaches top dead centre allows the engine to make better use of the fuel. Retard the ignition point ( move it nearer to top dead centre ) and the piston may have gone over top dead centre before complete burning has started. That’s why with a mechanical advance the ignition moves away from top dead centre or the original timing point so then at say 5000 rpm the ignition might be occurring at 15+ degrees btdc. So on a relatively slow running two stroke with fixed timing ( no means of advance or retardation) the closer to top dead centre the ignition the more initial throttle response the harsher or peppier the engine responds. The closer to the tdc position that the ignition is set means that although the Kickstarter spins the engine in the correct direction of rotation any tardiness in the operators kick may just allow the engine to start in reverse. I can see the point that you are making and was aware of that at the start, ignition advance potentially causing reverse running. Let’s face it we are talking about some really old engine design with very basic ignitions...just large lawn mower engines...even they now have a simple advance and retard map in their electronic ignition systems. Let’s just let our man with the Gripper which has leccy ignition experiment for himself, not sure if that has an ignition curve map. Hey it’s been interesting discussing with you this topic, just out of interest I run a Sherpa 250 with the ignition set at the manufacturers spec of 2.8 mm btdc, but with the vagueness of the contact breakers wear with the heel rubbing against the flywheel ignition cam ( felt pad oiled...high melting point grease on inside of heel....polished cam) after a few hours running the timing will possibly have gone off due to wear and the points closing up a little. More maintenance/ tuning but easier to fix if a fault develops. Your Sherco 200 will be running leccy ignition? ??

Advance means the spark occurs earlier, retard means it happens closer to tdc. So advancing the spark in terms of crank rotation means it happens at for example 10 degrees btdc, advancing further the spark could occur at 20 degrees btdc....retard the spark and you move back closer to tbc.

??‍♂️??????‍??‍?????or possibly ?‍???‍???‍✈️????‍???‍???‍? Me I just wake up in the morning and there I am....again???‍♂️?

I’ll mention a famous name... Miller, he told me that setting the timing at 3.25mm btdc would soften the engine performance and reduce any tendency to start up and run backwards...very embarrassing! Having spent a very long time on ‘t’ shop floor on the tools and then ended up teaching others about the suck,squeeze, bang, blow process et al. I have to say that with a two stroke that has no advance or retard map, mechanism, or vacuum device to alter timing as stated should produce a slightly softer engine as opposed to one set at 2.8 mm btdc. I used this setting on my 325 Sherpa and it was indeed softer or docile if you will, compared with another 325 that was very peppy and much easier to loft the front wheel....and it would start and run backwards...usually into a tree, with rider cursing vociferously! Timing on that beast was 2.8mm and I use these examples to help our man with his 250 Ossa Gripper. That timing was easy to remember ‘325’. I dare say our man with the Gripper will go with 2.7mm or there about. This concludes today’s sermon, ?‍??

The underside of the piston on any downward stroke will create a pressure in the crankcase. If this pressure cannot vent or escape it will find or make its own way out, such as blowing oil out of the main bearing seals, forcing oil seals out of their housings etc. So your breather pipe looks as though it was the issue here. Make sure all breathers are correctly routed and fitted to the correct inlet or outlet, check to make sure no breather pipes or connection points are blocked. Excess crankcase pressure can severely restrict engine performance.??

Fraid not, advance means to spark earlier ie 3.00mm btdc as opposed to 2mm btdc and retard spark later...closer to tdc?

Sounds like you need an M/X bike should have bought a Zook RM 250??

Best people to ask will be the importers, if they don’t know then they should! They then need to speak with the supplier, you would think with fuel being used in most countries now that attacks, eats and destroys valuable fuel system parts that the makers would be using the latest resins and hardeners to counter act the problem. For the cost of an aluminium tank I would be heading down that route.??

Setting at 3mm btdc would not do any harm as a starting point, but the manufacturers specs must be around some where! Not too sure if your Gripper may have electronic ign. Fairly convinced it’ll be on contacts breakers so go with 2.8mm btdc for zappy pick up or 3.25mm btdc for a bit less go and a softer engine??‍??

At least you hadn’t the threat of being suffocated by an over enthusiastic slug...and the smell...they just never cleaner their teeth.

Ah but you see we had to share it with a couple of dead beat slugs, ugh slime everywhere still no need for Brylcreem.

Looks like it’s been used as an anchor!⚓️

Condensation is the white smoke, hot gases cool air. Crankcase main bearing oil seals leaking allowing air to be drawn into crankcase causing weak mixture and unstable idle or increased revs. Never safe to ride with engine in unpredictable state. Other leaks could be carb to manifold, over tighten securing nuts and carb face flange distorts creating extra air inlet point.??

Have a good time Jarek??

You are going to struggle if you want to replicate the moves of a more modern and lighter bike, when the TY 250 A came out most riders were still perfecting wheelies! New fork springs would not go amiss and even spring spacers 20mm would give you the ground clearance that you will need. The old springs are fine but aged and soft after years in compression. New seals and flush out old oil, new oil, springs and spacers and you are good to go. Just don’t beat yourself up if you cannot bunny hop, technique is needed, get your riding skills improved over all types of obstacles, get more used to the bike and move that body weight over the front as far as you can with out being silly then throttle up and heave on the bars as if wheelieing and almost immediately throw your weight forward again, digging in with the heals of your boots. Have fun and look after what is the first of a solid bike.??

The yellow and red wires are for lighting only, suggest red to power horn and yellow for lights including stop light. As Stevem75 says green to a good earth and Black is ignition live coming from low tension coil in magneto and going to condenser and then travelling up to chocolate box connector near headstock, this then is connected to the low tension side of high tension coil under tank mounted to frame. It’s a popular modification to move the condenser from inside magneto to under frame near to ht coil as it is easier to get at if trouble happens.??

Yep saw that but images wouldn’t load for some reason.

Someone has invested a lot of time and energy here to make the Cub engine more repairable. There appears to be a drive chain clearance issue pic 2. What is the rest of the bike like?