Workings of a 2 Stroke Engine

[RD RACING]

ok, do you think a straight pipe say the same size as the header pipe with the same total length, would work better than this tuned pipe in pic ?

[phillysno1]

no, their would be no back preasure, that would resault in the unburnt fule not being pushed back into the chamber. meaning no turbo/powerband and profomace lost.

what i want to know is how the whole clutch works, i had a look on how things work.com but it didnt explain it to well,

Question:
with the centrealfugal clutch im asuming as the engiens spining at low RPM after its started it engages and as you turn the throtle and increase the RPM it enages more with the clutch bell and as you slow down their is less preasure and the clutch disengages, RIGHT?
well what i want to know is whats the diferance between a stock and 2shoe clutch and whats the ideal RPM to engage? also how would you tune a tuneable clutch?]

maby a new topic for things like the clutch flywheel and other non-fule related parts? for a broader understanding of how the engin works with out geting confused or lost in a mass of post's

[RD RACING]

thats spot on phill. also yes the clutch works by centrifical force of rotation, the stock clutch only relies on the spring tension, there are 2 types of springs, stock which are softer and heavy duty which are stronger so the stronger spring clutch will engage at a higher rpm. the better clutch is the adjustable type that can be tuned so to speak via tension nuts that can set in or out to suit the rpm engagement ie; low rpms or high rpms, a good setting is around the 6,000 rpm mark. prefere the 3 shoe adjustable type to the 2 shoe for wear.

[Stellerlicious]

so what reed spacers achive in this?

[mac90]

this answer was for post 31- 44 lol so we dont get confused about reeds anc crankcase compression

2 strokes work this way even a new engine will get some blow back into the carby
on each stroke this is why people install boost bottles to pick up the slight mix of air/fuel and air being blown back into inlet and saves it for next stroke the better / stiffer the reeds the less blowback into carby

on your next rebuild pull the engine over and cover the inlet hole with your lip you will feel the suction then a slight back pressure before the read seals completley

[RD RACING]

not if you have the perfect reed seal. when i build a new engine or just fit new reeds i allways do the blow and suck method to test reed seal via the manifold, example is ; say you have a dellorto manifold which is great for this type of test as you do have something to put you mouth over correctly, without carby attached and of course engine out from frame, blow into this and then suck in, if there is resistance the reed seal is spot on, if you feel there is no resistance when sucking into, you know the sael is no go. remove the reeds and start again until you have NO restistance atall.

[CLIFFO]

Should u use gasket glue on the reed and manifold gasket?

[Stellerlicious]

only on a gasket to manifold, not on a reed to a manifold, personaly i use gasket goo (blue stuff in a tube)

[Battle Guardian]

i like this thread, they should make more like this for ppl that are noob in small motors or pocket bikes

[pktbikeuser]

hello to all this question may not apply to topic and I apologize up front but..
I bought my son a pocket bike 49 cc and after running it maybe 16 hours the motor has a tendency to lock up to the point you cant pull the start cord and the back tire locks up.I pulled the sprocket cover off and pushed the front drive sprocket inward toward the carb and it frees up .does anyone have an idea what is going on?your help is greatly appreciatted