What is Engine knocking?

What is Engine Knocking?

If I ask this question to most of the ones who rides a motorcycle in India, I can bet that the most probable answer would be something like this:

If you are riding at top gear and the bike is at slow speed say around 20 kmph; in such a situation if you suddenly twist the accelerator without shifting down a gear, then instead of a smooth pick up, the engine will start behaving as if it’s gasping for breadth and struggles to move forward. This causes the bike to move in a jerky manner instead of moving forward smoothly.

This is knocking".

I wouldn’t be surprised if the above answer comes not just from a layman but even from many of out so called "desi" bike experts

What has been described above is actually Engine "SNATCHING" and NOT Engine "KNOCKING".
Why does Engine Snatching occur?
Imagine someone is holding your hand casually and loosely. Now if he/she decides to pull your hand suddenly then you will surely experience an unpleasant jerk won’t you? The same phenomenon occurs with the engine, when the slow moving parts inside the engine are subjected to a sudden motion.

What we instinctively do in such a situation is either shift down a gear or let the engine revs rise by slipping the clutch.
If that is Engine Snatching then what is Engine Knocking?
Engine Knocking is actually a Pinging/Metallic sound which can be heard from the engine when the air fuel mixture is not burnt in the optimum manner.
Causes of engine knocking could be: Due to..
•Carbon deposits
•A lean air-fuel mixture
•Low coolant level, or cooling system problem that causes the engine to run hotter than normal


Posted below is a video in which a car engine makes "Knocking" sounds when revved: Click here, if one cannot see the video.

info-2wheelersindia.com

Bajaj Auto hikes prices to offset input costs

Bajaj Auto, the country's second largest motorcycle manufacturer, has increased the prices of all its bikes in a bid to pass on the burden of high input cost to the customers.
The price hike will be in the range of Rs 800 to Rs 1,000. The move comes close on the heels of the market leader Hero Honda’s price rise of its products by upto Rs 1,000 earlier this month.
“The company has sent the letter to the dealers on price hike almost eight to nine days ago,” a n executive of Bajaj Auto said.
The increase in prices would help the Pune-based automaker improve its operating margin which has been under pressure due to cut-throat competition in the motorcycle market amid high commodity prices.
“We have increased prices across all the models including Platina. The increase varies from Rs 800 to Rs 1,000. On selected bikes the hike is Rs 1,000. The revision in price is the result of increasing material price,” Bajaj Auto CEO (two wheeler) S Sridhar told FE confirming the development.
Bajaj Auto sold 2,69,488 units of motorcycles in May led by Pulsar and Discover, registering a growth of 63%. Almost all the bikemakers the last few months seen their sales soaring on the back of robust economy and growing purchasing power of the people in rural India. The industry has seen exponential growth mainly due to low base in the first six months of last financial year.
“The growth will continue as overall economic environment is positive,” an industry watcher said. The two-wheeler manufacturers, however, are expected to see pressure on their margins mounting up due to high input cost. While there has been correction in the commodity prices in the last one-and-half months the prices are still significantly high on year-on-year basis.
“Before the correction about a month back, the input costs were up 20%. Bajaj might have increased prices sensing margin pressure in coming quarter,” auto analyst at brokerage firm Vaishali Jajoo said.
Two-wheeler manufacturers are able to pass on the increase in input cost as demand is on the rise. According to Society of Indian Automobile manufacturers (Siam), domestic sales of two-wheelers increased by 25.43% to 17.92 lakh in April-May this year as against 14.28 lakh in the first two months of the previous fiscal. Production during the same period jumped 31% on increased economic activities.

125 cc Sports

Engine: 125cc


Power: 15bhp (restricted

Power: 30bhp (de-restricted)

Top speed: around 75mph for 15bhp

Top speed: around 95mph for 33bhp

Cost: £3799 (UK)
So, we thought 125cc bikes were boring? Get hold of the Aprilia 125 and de-restrict it, freeing all the 33 horses, and 125cc biking will never be the same again.
The Aprilia RS125 has remained the best fun 125cc bike for ages now. It was first launched way back in '95 and still remains an average teenagers' dream bike. Looks like a biggie, handles like a track bike and the engine can be de-restricted to 30bhp which means it can tease cars on the road as well! It’s a tad expensive to buy and run thanks to pricey two-stroke motorcycle oil, but, if you can afford it, the Aprilia RS125 is worth every penny.

Royal Enfield Electric

Don't 99% of bikers go in for a Royal Enfield for its thump, the sound of the big single motor? Well, James Hammarhead thinks a little differently. How about replacing the 500cc engine with a, well, an electric motor! Gulp!


Called the Volta 102, it is now powered by a 6 KW lithium iron-phosphate battery pack and an EnerTrac hub motor. The fuel tank now houses two 110-volt, 15-amp chargers that take about 4 hours to recharge the bike.
 
Performance? The motor makes around 13.4 hp continuous and about 40 hp peak. The original 500cc engine managed around 18 horses. The weight of the Volta is more or less same as the original bike and hence, no surprises that the bike should hit a top whack of around 100miles or 160km/h. Thank god there is front disc brake to stop the heavy lump of metal.

You can have one for, hold your horses, US$ 18500 or around 8,20,000 Indian rupees. No thank you, I did rather go in for a Japanese missile
 

Triumph Sprint GT

We have always had a soft corner for the Triumph Sprint and with its touring avatar finally out, we have even more reasons to want to ride this bike. Christened the Triumph Sprint GT, the changes made to the GT version are quite a lot. Yes, we know you already noticed the new low slung exhaust which have now replaced the under-seat ones.

 Some one tells us these help pump up more power and torque too! The seating posture is and comfortable, there is bigger wind screen, better headlamps for night riding, standard 31 litre panniers and of course ABS assisted brakes. On the option list, owners can opt for a top box that can hold two full-size helmets and also includes a 12 volt power supply for charging mobiles / electronics on the go.

The Triumph Sprint GT will be available in the US market this Fall as an early release 2011 model and will carry a sticker price of $13,199 or around Rs 5.9 lakh in Indian currency