brief introduction on velozeta's 6-stroke engine

1. 6STROKE ENGINE
TECHNICAL SEMINOR
ON
BY
MANIKANTAN.M
1HS11AE024

2. Contents
 What is 6-stroke engine and why we need it?
 Types of 6-stroke engines.
 Velozeta’s six stroke engine.
 Engine parts modified.
 Working principle.
 Comparison of 6-stroke with 4-stroke engine.
 Advantages and disadvantages.
 Applications.
 Conclusion.

3. 1st approach 2nd approach

4. Velozeta’s six stroke engine
 A four stroke Honda engine is altered to form the six
stroke engine
 First four strokes are same as a conventional four stroke
engine
 In the fifth stroke, air is sucked in to the cylinder
 In the sixth stroke, a mixture of air and unburned gases
leaves out.

5. Engine parts modified
1. Camshaft / Crankshaft Sprockets:-
 Crank has 1080 degrees of rotation for 360 rotation
of camshaft
 Hence their corresponding sprockets are having teeth
ratio 3:1
 34 teeth sprocket of camshaft in the four stroke is
replaced by 42 teeth sprocket
 17 teeth crankshaft sprocket is replaced by 14 teeth
sprocket

6. 2.Cam lobes:-
 360 degrees of cam has divided into 60 degrees
among six strokes
 Inlet valve is opened in the first stroke only and
the exhaust valve, in the fourth, fifth and sixth
strokes by the exhaust valve cam.
 The exhaust valve cam is double lobed

7. 3.Valve Timing:-
 IVO at 0 degree at TDC
 IVC at 25 degree after BDC
 EVO at 0 degree at BDC which was 25 degree before
BDC in the original engine
 EVC at 10 degree before TDC
 Air inlet reed valve is opened in the fifth
stroke and then for the sixth stroke exhaust
valve is opened

8. 4.Secondary Air Induction System:-
 It supplies air which is used in the fifth and sixth
stroke
 During the fifth stroke air is sucked into the
cylinder through a reed valve provided on the
secondary air induction line
 In the sixth stroke a second reed valve at the
exhaust manifold opens and removes the mixture of
air and unburned gases

9. Working of the engine
First stroke:- During the first stroke the inlet valve opens and
air-fuel mixture from carburetor is sucked into the cylinder through
the inlet manifold .
Second stroke:- During the second stroke, piston moves from BDC to
TDC, both the inlet valve and exhaust valve are closed and the air-fuel mixture is
compressed. The compression ratio of the modified engine is same as that of the
original four stroke Honda engine 9:1.
Third stroke:- During the third stroke, power is obtained from the engine by
igniting the compressed air- fuel mixture using a spark plug . Both valves remain
closed. Piston moves from TDC to BDC.

10. Fourth stroke:-
During the fourth stroke, the exhaust valve and the reed valve opens
to remove the burned gases from the engine cylinder. Piston moves from BDC to
TDC.
Fifth stroke:-
During the fifth stroke, the exhaust valve remains open and the reed
valve closes. Fresh air from the air filter enters the cylinder through the
secondary air induction line provided at the exhaust manifold . The reed valve
opens.
Sixth stroke:-
During the sixth stroke, the exhaust valve remains open. The air
sucked into the cylinder during the fifth stroke is removed to the atmosphere
through the exhaust manifold . The reed valve opens and the reed valve closes.

11. 1. Rings 17. Connecting rod
2. Inlet Manifold 18. Timing Chain
3. Cylinder Head 19. Sprocket 14T
4. Cam shaft 20. Crank
5. Cam Lob No.1 21. Secondary air induction unit
6. Inlet valve 22. Reed valve (One way valve)
7. Sprocket 42T 23. Reed valve (One way valve in Exhaust manifold)
8. Rocker Arm 24. Air filter
8.1. Inlet Rocker arm 25. 42T sprocket holder
8.2. Exhaust Rocker arm 26. Bearing
9. Head Cover
10. Cam Lob no.3
11. Exhaust valve
12. Cam Lob No.2
13. Exhaust Manifold
14. Spark plug
15. Cylinder
16. Piston
Detailed label of velozeta engine parts

12. Comparison between 4-stroke and 6-stroke engine

13. Advantages
Reduction in fuel consumption
Reduction in pollution normally up to 65%
Better scavenging and more extraction of work
per cycle
Lower engine temperature - easy to maintain the
optimum engine temperature level for better
performance
The engine does’t require any basic modification
to the existing engines. All technological experience
and production methods remain unaltered
Higher overall efficiency

14. Applications
IN RACING CARS.
IN HEAVY VEHICLES.
EARTH MOVING VEHICLES.

15. Conclusion
The six stroke engine modification promises dramatic
reduction of pollution and fuel consumption of an internal combustion
engine. The fuel efficiency of the engine can be increased and also the
valve timing can be effectively arranged to extract more work per
cycle. Better scavenging is possible as air intake occurs during the fifth
stroke and the exhaust during the sixth stroke. Due to more air intake,
the cooling system is improved. It enables lower engine temperature
and therefore increases in the overall efficiency.