LAMBRETTA MYTH BUSTED

[@michaelbeecroft9747]

Personally I think the 4 point seizures are caused by thicker studs not being elastic enough to stretch with the cylinder expansion at higher temperatures resulting in cylinder wall buckling local to stud areas

[@TheSteelweasel]

needs more testing to determine that .

[@daveb1963]

I use exol fully syn it has flash point 144 and is very well priced if you buy 25ltrs drums £80 delivered. Great videos learnt alot about porting and such like.....

[@Smarterthanyou-mthrfkr]

The interruption of the fin shape from the holes is creating strong and weak points

[@skoot2u]

Great video, I was waiting for the oil bottles to melt as well !!

[@TheSteelweasel]

they got a little warm🙄

[@daviddanielstephenson2833]

One of the biggest mistakes people make when tuning an engine is, not taking into account the amount of fuel entering the system at all ranges of TP, IE, fuel also acts as a cooling agent as does oil levels help to increase compression at higher mixture rates. At full throtle and the main jet is fully open and where you get the best cooling as it is running richer, but at half or less throtle the pilot jet is more extant at the lower TP, if the engine is running weaker at these lower stages it can get hotter quicker than it would at full throtle. What you need is a good rolling road/dyno and someone who knows what they are doing, going it alone and simply bolting bits on is asking for trouble and an empty wallet and all sorts of uneducated guesses and myths arise. These engines were not designed to produce high horsepower and very anciet technology, you cannot make a silk purse from a sows ear, and why they are making completely new designs from the ground up. As far as the studs expanding, even past the curie point it is impossible for it to gain such large sizes, it would begin to flash off and burn away not expand.

[@robertbroadhead6173]

yeah its all down to wot you feed it oil flash piont imo,back in 2001/2 coming back into scootering i rebuilt my TV175-3 engine new rebore ect from AF i used 2st oil from my local garage,my first nip came after 1 mile,15 nips later and several clean ups i gave up it sat in shed for weeks,then one night on LCGB forum this old boy racer was telling someone else with similar problem about an oil that would help even if you have standard machine,i had to send away for some drained tank mixed it at 4% with new petrol went out on b road for around 8miles no seize came back on A road flat out at 45 the bugger didnt seize,,,it gave me confidence to build up the 200 casing i had,no nips no looking back,changed rings 2/3 times in the next 10yrs no gumming up as oil has a cleaning agent

[@TheSteelweasel]

great story my friend this is the kind of stuff i love.

[@robertbroadhead6173]

@@TheSteelweasel forgot the oil recomended was Rock Oil Synth 2 injector,amazing it stopped the 175-3 15 nipper from seizing lol,,,,the jetting was correct on it

[@TheSteelweasel]

@@robertbroadhead6173 yep I think it's one of the best around oils for lambretta 150 c flash point and clean burning

[@kevinhendon]

Great test Steve, that title could be made into a TV program😉.................Mad Professor 😂👍

[@richardshipman8399]

good test for the studs , but a bit of an inconclusive test overall as the expansion of the cast cylinder has not been accounted/measured for , material thermal dynamics can be complicated love the videos keep em coming Steve do you still play in your band ?

[@TheSteelweasel]

all i need is a thermal camera buy me one please , ha ha

[@keithappleyard642]

Can it happen on all barrels? Are some more prone than others? Do barrels that have been bored out to max or near max leaving a thin wall suffer more? I agree and don't think a stud could expand enough to course it. Has anyone had it happen with the thinner rolled stud, which I believe would be original innocenti design ?

[@TheSteelweasel]

theres alot of factors in this , quality , bore size , piston expansion rate , torque settings , etc etc

[@stevenmay3409]

Could it be the barrel wall thickness around the stud holes being a bit thinner and heating up quicker causing a hot spot?

[@TheSteelweasel]

yes its exactly that but also the stud hole does not transmit heat away so its even worse .

[@markletts8802]

Quick question.having recently become the proud owner of an LD..Where do I stand regarding engine mods,just to make her,respectable for road use,the one I ride was painfully slow,I know bolting a TS1 to her isn't feasible..where should I start..

[@TheSteelweasel]

Dont think anyone is doing stuff for LDs only casa lambretta does stuff for Vega and star stream they might have something for you . I've never touched one so i cant help

[@travezripley]

Don’t call us, we’ll call you.

[@CarlEves]

Interesting again the flash point on oils has never crossed my mind. Better get in the garage and check my Uber expensive Plutoline.

[@TheSteelweasel]

122 C

[@Lambretta-images]

I think you are misunderstanding why studs result in 4 point seizures, it has nothing to do with the stud expanding and putting pressure on the barrel wall from inside the stud holes lol. I can't say I've ever heard anyone suggest it is due to expansion of the studs until watching this video lol. Bonkers.

[@TheSteelweasel]

@@Lambretta-images yes it is bonkers and false its caused by the void and lack of heat conduction around stud area .

[@TheSteelweasel]

so what your theory ?

[@CarlEves]

@@TheSteelweasel ah perfect. Mines running between 100c and 120c at full pelt. I’m using the MX9. I’m in recovery from open wallet surgery every time I buy a bottle. I feel confident with it and that’s half the battle when riding a Lammy.

[@bianchetfam7960]

Hi, loving the vids. Do you know what the Flash Point of a standard lammy 200 is? I'm asking as my fully synch oil states that it's 90C. Wandering now if my oil is right? Thanks

[@TheSteelweasel]

the oil has a flash point of 90c so you need to determine the wall temp of cylinder , if your head is 90c the cylinder will be cooler .

[@TheSteelweasel]

90c is middle of the road and will be good for standard motor 👍

[@johnbianchet3070]

@@TheSteelweasel Thank you

[@captainpugwashy]

@@TheSteelweasel the flash point of petrol is -30C and that’s mixed at between 96 to 98% with the oil. My question is, wouldn’t that reduce the flash point of any oil once it’s been mixed with petrol ?

[@TheSteelweasel]

@@captainpugwashy no they are never truly mixed .

[@JonBilbaoMallona]

Those tools holding there are metric? or imperial

[@TheSteelweasel]

Metric mate

[@jfrorn]

I was wondering what that kit off that Serveta was size wise? My idea was that it had been bored out to 65mm (190-5) and that may have contributed, the walls being very thin? It looked like a big piston... I'm assuming the motor was a small block of course.

[@TheSteelweasel]

its 62 mm indian sr kit famously bad but clearance was 3 thou and now its 4 thou after clean up

[@jfrorn]

@@TheSteelweasel The piston clearance? Did you hone it?

[@TheSteelweasel]

@@jfrorn yes 3 thou