Thanks. I haven't seen much about these new motors. @bigissue, these engines do not have hydraulic self-adjusting valvetrains. Valves--especially the exhaust valves get longer during use, reducing their clearance and then they won't seal well. If the valves don't seal against the seat because the valve-train is holding it open, the valve and seat will get hotter than they need to, which further accelerates their stretching and seat wear. During that time, the engine just won't have as much power as it should because the engine can't keep compression after the sparkplug ignites the fuel-air mixture. I've heard from a Vespa mechanic of an engine that would not start from valve-clearance issues alone, likely because modern Vespas, already have an engine-decompression system to reduce the load on the starter, and having leaking valves might lower it until the point where it wouldn't start at all.
Unbolting the rear shock makes it possible to get the valve cover out. Otherwise, I couldn’t get it out. My biggest problems with the valve check was being able to refit the valve cover and keeping the o-ring/seal in place. It fell out every time. I used a small amount of tacky grease to hold the o-ring in place. Find feeler gauges like the ones robot is using. The standard feeler gauges are hard to use. I did the two intakes from the top reaching down as opposed to using the access panel. Two of my 3 valves were tight.
why is it according to the manual it's both .08 mm for both intake and exhaust? and robot uses .004 for the intake and .006 for the exhaust. I'm a little confuse.
hello mr robot,i just take back my primavera 3v from a workshop that lies to me..n when i check the head cover i realize i lost 1 part bcoz i see in ur video u have it there..what u call it crank lock or what..im sorry bcoz im new ...is it ok i didnt hve it there?
Good day. Hello to you from faraway Kazakhstan. If it is not difficult to tell me please. I have a Piaggio ZIP engine 125 carburetor. I want to install it on the Vespa LH 50 2t scooter. Which sdi switch is suitable for starting this engine ????. In addition to the ACI503. I will not have an immobolizer. Thanks for answering.
got a problem with a primavera 50 (carburation and 4stroke)... it starts, revs up itself and inmediatly after 10 secs stop. Then if you let it rest 2 min it will start again with no problem and stop again......any thoughts?? carburetor , valve adjustment, air leak.......???
loss power after valve adjustment, setting was .10mm and .15mm @top dead center, still no power, before adjustment - power is very good? what makes a problem? pls help. thank you
Frank Pa check the valve... If there any crack or you haven't polishing it... Also check if your valve was bended or not... It's really important thing for compression
Great video!! I was wondering if it is the same way of adjusting the valves for a 4 valve engine? (I have a 4 valve SOHC Piaggio engine for my Aprilia Atlantic 2007)
Hopefully, I can ask a question here? I take delivery next week of a new Primavera. As I live 200 miles from the dealer (and 150 miles from the nearest Vespa dealer). I can change the engine oil and filter myself as well as the gear oil, but adjusting the valves is well beyond my skill set. As the valves on the engine shown here were slightly tight with just a few miles, my questions are these? Are they tight from the factory or do they tighten up with initial use? Is there any point in having the dealer check the clearances on the brand new engine before they ship it to me? If not, will I need to transport my new scooter to an authorized dealer to have them checked at 625 miles? Thanks much.
My experience : A reputable dealer will not let a scooter leave with bad valves...they will only get worse by 600 miles. If you are careful to not overheat the engine for first 300-500 miles, valves should be good till 1200, when you should probably return to that dealer for a checkup. Again. a reputable dealer will understand your geographical problem in being "overdue", because Vespas don't have valve issues as a common thing, anyway. Valves just slightly out are not a fatal or totally uncommon problem even for well manufactured scooter motors. For sports and race cars, maybe.
I know you already resolved this, but for anyone new reading this: Robots video is 9 years old. Specs change over the years. My manual AND the sticker in the underseat bucket varies from the older model. Check your manual or the sticker in the underseat bucket for the correct spacing for you model.
hey people valve adjusment on first service are vespa crazy get a 300 gts had it since 2009 change the oils new exhaust tyres engie mounts and tighting steering bearings all cheap to do and still going after 40000kms forget this engine
Atanasius Kurnia Correct valve clearance for these bikes is .08mm for both intake and exhaust, according to my 2015 Sprint owners manual. I can't tell if Robot made a mistake, or if his shop prefers these looser clearances based on their experience.
