Whew! some list of queries these
. I cannot of course go into details without falling flat on my key board from exhaustion. Will skim the surface but be as relevant as possible.
Quote:
Originally Posted by kaynmantis
What's "CG"?
I too have a query. Was wondering how much would the angle of the fork have effects on the handling of the bike. Like some cruisers are angled quiet extremenly while normal street bikes are almost perpendicular. I unserstand, extreme angle would like cruisers would have longer wheelbase hence bigger turning radius, unflickable etc.
But on a normal street bikes we used here, how much would the angle effect the handling characteristics?
I'm also thinking, the contact patch of the tyre on the road will also differ due to angle.
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The 'angle of the fork' is what is called the 'rake angle'. (see my pervious posts in this thread for illustration of the same) Cruisers are meant to 'cruise' and so have large rake and also large 'trail'. This makes them more stable in a straight line. More stable means more reluctant to change direction. So less 'flickable'.
Steep rake if allied with small 'trail' makes a bike more prone to direction changes. This also means 'unstable' in English
.
Normal street bikes have rake angles measuring around 23-25deg and trail values around 2.5 to 3 inches. Cruisers can have the front raked to even 35deg and trail can be 4.5 to 5 inches.
Motorcycles are in fact designed with some bit of inherent stability built into them. If it were not so they would be dangerous or impossible to ride.
Turn radius is more dependent on the 'lock to lock' angle than on wheelbase or rake. For example, the Suzuki Intruder (a cruiser with a long wheelbase and large rake) has a tighter turning circle than the Yamaha R1 (with its shorter wheelbase and steeper rake). The Inturder handle, in simple terms, can be turned through a larger angle measured from full right to full left.
Quote:
Originally Posted by samudranb
Lol! Please do let us know when it is published! I will be the first to buy it!
You really explain really well!
I have another question: What is the relationship between the weight of the bike with the width of the tyres? I used to think that the wider tyres are for heavier / more powerful bikes, but then what about the Bullets?
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Weight alone is not the defining criteria for tyre choice. Power output, torque produced and speeds possible all carry equal or more importance. Usually, the more the power required to be put down on the road and the faster the bike is expected to travel around corners, the wider are the tyres. And also usually, the wider the tyre the softer its rubber compound can be without getting overwhelmed by the riding loads.
The Bullet, ZMA, P200 or even P220 make almost similar power and so tyre widths and compounds are more or less the same. The R15 is optimized for low weight, low drag and low rolling resistance. So it needed a specially developed soft compound narrow tyre (even though this tyre will not last as long as the ones on other bikes do).
Quote:
Originally Posted by outworldly maniac
awesome discussion going on 
unbelievable OF sir ......
noob sawal
why do people crave for more cylinder engines ??
like suppose we have two bikes A and B of 250cc
A with a single cylinder with same power and specs like B
B with a twin cylinder n same specs like A
then what does make a difference actually
we are getting the same amount of power... same torque ,,,
@ OF sir
please could you elaborate this
Trail Braking is a technique where the rider progressively reduces his braking force as he gets deeper into the turn and closer to the apex.
i am not understanding this..... we keep the brakes pressed and slowly and steadily keep on releasing it
is it what i am saying ??? then how will we maintain speed or for that matter even ride at a speed with more part of the brakes pressed
or it is that i dont understand what u meant by BRAKING FORCE 
please explain sir  |
Noob question first : its a very long story with no positive conclusions at the end of the day. The pros and cons can fill pages. Usually, more cylinders for a given capacity means smaller pistons which in turn means quicker revving and higher rpm at red-line. Track bikes or those targeted to high top speeds would preferably have this configuration.
Vice-versa less cylinders means larger pistons, more reciprocating inertia and so relatively slower revving. also piston speeds limit the RPM red-line to lower values. In practical use, better suited for touring/commuting/off-road use.
Your question #2: Trail Braking: you don't maintain speed through a turn. You continue braking almost till the apex and then start accelerating as you straighten the bike out of a turn. See the diagram I'd posted in my previous mail. I cannot get clearer than this.
Quote:
Originally Posted by abhijeet080808
Thanks for the awesome explanation OF. Cleared a lot of my doubts.
One question -
What are the factors that determines the ignition timings in a 4 stroke engine? How does the following factors affect timings -
1. Compression Ratio
2. Air-Fuel Ratio
3. Altitude
4. Temperature
5. Valve Timing
And any other factors you may think off!! |
Abhijeet babu..
.. this is not ONE question by any standards. These are FIVE questions rolled into one. And again a long story. It will be great if you can whittle them down to specifics that you have confusion about. Discussing the relation between just compression ratio and ignition timing will take more than a few posts.
The primary reason is that ignition timing is a very dynamic activity that varies not only in magnitude but also across time. Discussing the interplay of all elements is just beyond us on a forum. Put up something specific and we'll explore it together.