Very good example, thanks for explaining like this

A 3-valve is almost as efficient as a 4-valve. Both the valves open and close at the same bike and not like what someone mentioned here.
In the TVS flame, the port flow into each valve is controlled by stacking one port over the other and as the slide opens beyond 50%, the 2nd port get the charge. Its a clever tech by AVL.
Now having a single exhaust valve does not mean it will underperform. It will still be more efficient than a conventional 2 valve head.

Nice example , understood!

About the flower-head thing, i think CL-II never came with a flower-head. some early Model-B(1973-74) yezdi had a flower-head, but was later shifted to the normal that we see more more often, Roadkings with FH, maybe i have to explore more of India to see it.
i think you should ride a Y350 to know whats the difference between Y350 and Fury. Numbers, sometimes, dont show the actual performance.
Fury 175, in no way, can do anything to Y350, Roadking .
How do you say that Y350 was dated ? simply coz it had CB point system ? more than 50% of Ys and all Jawas are on CB Point system in the country and people are happy to ride it. it might be dated if you look at the lipstick, powder and makeup of it, i agree.

i had a question in mind but didn't knew where to ask it,so if this is the wrong thread then forgive me.
why do disc's of disc breaks in bike have small holes in them and whereas the disc from a car is totally smooth?

I'll clear your doubts one by one.
*The Roadking did have a flower head on its last days and we already have a few. My friend owns an assortment of spares and that includes some factory cylinders. Yes, you need to explore the other part of India and more so, Mysore which is where the factory was located. I've been there 4 times when the factory was stripped down and parts auctioned. I have seen all the factory prototypes and seen more than what i can type here.
*Have i riddden a Y350? My dear friend, I was using one for a short while. I very well know how good it is.
*And I have ridden some good Furys as well, so I can comfortably comment on the performance and not going alone by the performance figures.
*Why is a Y350 dates?
- Has a really dated intake system. 2 cylinders fed by just one 28mm carb which makes it seriously underpowered
-have you ever seen the transfers? Its a 40yr old tech
-the internal transmission layout with a chain drive is again decades old when an RD has a positive gear type transmission.
-busting internal oil seals which is the most unreliable thing about the Y350 and the tech used all through the engine is really dated. jawa did nothing about updating the design or their flaws
*The jawas/Yezdi all ran with CB and so did the RD. That alone does not make something old tech. The overall engine design is what matters.
The Roadking however is my favourite and it was the better one of the lot.
Being on this part of India where I get to ride and see better and more Jawas/yezdis and having worked on a few bikes myself, i sure know of what I'm talking. Hope you clear now.

The holes are for ventilation.

Observe the scorpio s Discs the next time. U would see some pattern on it. Most modern cars also have ventilated discs but u should observe them parallely. They are like two discs sandwiched , which is also for ventilation.

They are called perforated discs.

Re-igniting the old Thread

Some More to put some fuel in the Fire:


1) DTS-Si means..??

2) CBZ has got ATFT..?.? What is ATFT.?

3) What does Sprung and Unsprung Wieght Means.?

4) What is the basic Difference between chasis of Pulsar(Double Craddle) and R15.(Delta Box frame)

5) Karizma was launched in year?

answers in bold, no cheating honest:d

Good Work Sir!!!

a very interesting thread, read it from first to last.

some questions that are comin into my head - im gonna keep it simple so dont pooh pah em off -

1) Enfield taurus Specification, and number of gears ?

2) Which bike in india to have a mechanical timing advancer ?

3) company claimed top speed of RX100?

4) What was the front tyre pressure recommended for the RX100 ( which generally never is set correctly )

5) the oldest bike engine in india? ( in production)

6) smallest capacity motorcycle to be launched in india? ( not moped or scooter )

7) smallest capacity geared scooter to be launched in india ?

8) After the chetak/priya/super/cub, the first geared scooter by bajaj ?

9) only bike to be tested for 24 hours non stop ? ( really easy )

10) Chain drive scooter launched in india ?

here is something I know,
1.) DTS-Si - Digital Twin Spark Swirl Ignition

3.) Sprung weight is the weight supported by the suspension system. The other masses like wheels,tyres, sprockets and suspension itself are Unsprung weight.

When a brake pad rub against the disc, due to the heat, the brake pad material emits some gases. This gas will form a thin layer of surface film which modifies the coefficient of friction and degrades braking. To ventilate this gas, holes are used.

The holes on Scorpio is to reduce brake squeal.

Yes, most cars uses ventilated disks. They have a spiral path way between a pair of disks which acts a centrifugal blower to take away the heat.

answers in bold.