How do I know if my 2 stroke crank is bad?
How do I know if my 2 stroke crank is bad?
Any vertical movement in the crank bearings is bad, you can check this by removing the flywheel cover and pushing up/down on the flywheel. Also bad is any vertical movement at the rod/crank pin, but this will require removing the cylinder to inspect.
What is crankshaft truing?
Truing is the process of aligning of the crank assembly on its straight-line axis in order to get the axial runout as close to zero as possible. In contrast, balancing is adding or removing weight in certain areas of the crank to ensure the weight is in equal balance across the entire crank assembly.
When should I rebuild my bottom end 2 stroke?
The bottom end of a two-stroke can usually take around 70-80 hours before rebuilding, however, it all comes down to the way the bike is being used. It’s always advised that when you rebuild the bottom end to also rebuild the top end.
What is the purpose of crankshaft deflection?
Crankshaft deflections are measured to detect the misalignment of main bearings. The misalignment occurs due to bearing wear or deflection of the crankshaft. The horizontal and the vertical misalignment are checked.
How do you split crankcase without tools?
If you do not have a crankcase splitting tool, splitting the cases is possible using a commonly available harmonic balancer puller (available at auto parts stores) along with 2 (long) 6mm x ~150mm bolts and a dead blow hammer.
How many hours is alot for a 2 stroke dirt bike?
A 2-stroke piston can last over a hundred hours if the bike was casually ridden and properly maintained, but an aggressive motocross racer can wear out a top-end in less than 20 hours of ride time.
Why was the two stroke crankshaft so popular?
The two-stroke was recognized as having substantial theoretical promise, as it delivered a power stroke for each 360 degrees of crankshaft rotation but the hard reality was that each individual power impulse was too feeble to amount to much when totaled at the output end of the crankshaft.
How does a two stroke engine change timing?
In contrast, a two-stroke engine’s valve timing may be altered simply by reshaping the holes in its cylinders, and its power output markedly changed by utilizing inertia and resonant effects in its intake and exhaust tracts. None of these modifications are costly.
Do you need dollar inputs for two stroke engine?
On the other hand, while the two-stroke engine does not commonly require large dollar inputs to raise its power output, it does require an in-depth under- standing on the part of the man doing the modifications.
What is the limit for power strokes per unit of time?
The limit for power strokes per unit of time is established by what is tolerable in terms of crankshaft rotational speeds, and tolerable here is what the bearings, rod and piston will survive, in inertia loadings, for what you consider an acceptable service life; the design engineer has already expressed his opinion in this matter.
