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**aargee** · 08-09-2011, 07:47 PM

Originally posted by Rahul Rods Tewathia View Post

no bro not in all gears only in 4th gear just to try that my bike is ok or not like u said that on highways your bike wont cross 8 or 9 k rpm ...

Tks for that. Let me give a try next week.

But I'm still confused as how a bike's top speed would increase if anyone try hitting 9K RPM on every gear while the same bike does only few Kmph less when its revved to normal. Any takers for discussion pls? Especially the ones who're blessed with 145 Kmph C250R's. Pls share your experience on making the top speed pls. Tks.

**neoakshay** · 08-09-2011, 07:53 PM

Originally posted by aargee View Post

Tks for that. Let me give a try next week.

But I'm still confused as how a bike's top speed would increase if anyone try hitting 9K RPM on every gear while the same bike does only few Kmph less when its revved to normal. Any takers for discussion pls? Especially the ones who're blessed with 145 Kmph C250R's. Pls share your experience on making the top speed pls. Tks.

What top-speed are you guys hitting on your CeeBeeArr's..? I dont think 145kmph on a CBR250 is 'blessed', should be able to do much more. My R15 did 145kmph while it was stock! All you guys getting stressed with top-speeds, heres some advice for you - your bike's engine will only open up fully post 7-8000km on the ODO. Try after that for a proper top-speed figure.

**aargee** · 08-09-2011, 07:56 PM

Originally posted by neoakshay View Post

your bike's engine will only open up fully post 7-8000km on the ODO.

Whaaaat????

The question here is not 145!!! There're few guys who have done 156 on ODO & few others who haven't been able to do more than 135. One of the suggestion was to try & hit 9K RPM on every gear to cross 140 & I was seeking clarification.

If the bike's engine will open only after 7-8K Km on ODO, then how come there're few guys who were able to do 150+ by 2-3K on odo. And yes, I'm talking about stock too.

**psr** · 08-09-2011, 08:03 PM

Originally posted by aargee View Post

Tks for that. Let me give a try next week.

But I'm still confused as how a bike's top speed would increase if anyone try hitting 9K RPM on every gear while the same bike does only few Kmph less when its revved to normal. Any takers for discussion pls? Especially the ones who're blessed with 145 Kmph C250R's. Pls share your experience on making the top speed pls. Tks.

I think it is because of the top gear ratio being less than 1:1 ratio...
For instance in ZMA also the 4th is 1 :1 and it is in this gear that the enigine had to be revved to max before shifting to 5th to get 135 or 140 Kmph, in ZMA...because the 5th Gear ratio is 0.8, wherein the bike weight loads more on the engine .Under normal shifting at 4 to 5 K RPM ZMA will achieve 120 in top gear, and RPM may not rise to full 9 K+.
At max RPM Engines produce less Torque and pulling power than say at 80% of max RPM...just my thought.

**psr** · 08-09-2011, 08:22 PM

Here is an interesting link

Choosing the right Motorbike

**Rahul Rods Tewathia** · 08-09-2011, 08:56 PM

Originally posted by aargee View Post

Whaaaat????

The question here is not 145!!! There're few guys who have done 156 on ODO & few others who haven't been able to do more than 135. One of the suggestion was to try & hit 9K RPM on every gear to cross 140 & I was seeking clarification.

If the bike's engine will open only after 7-8K Km on ODO, then how come there're few guys who were able to do 150+ by 2-3K on odo. And yes, I'm talking about stock too.

like r15 if we change 5th gear on 120kmph to 6th then its not able to touch 130 kmph but if u wana touch top speed then u need to pull your bike hard till 130 or 135 kmph in 5 gear then only u can touch 140kmph..
and if u change 5th gear to 6th on 125 kmph then it will not go more then it.
did this thing wid pillion ..

**aargee** · 08-09-2011, 09:31 PM

Much awaited reply

Originally posted by psr View Post

I think it is because of the top gear ratio being less than 1:1 ratio...

So, you're saying that the top gears are enabled only to cruise; beyond the max torque, on top gear, the bike stays nearly to what top speed it is. If one needs to achieve good top speed, they've to accelerate hard on every gear so that the top speed is increased at top gear -1 & upon top gear, the increased top speed is felt. Am I right?

Originally posted by psr View Post

At max RPM Engines produce less Torque and pulling power than say at 80% of max RPM...just my thought

Right; so that's the reason the pull is less on top gear. So ideally, the bike shouldn't rev past 8.5K RPM (max torque) is it?

This video answers most ppl's agreement as well; nAling revs upto 10.5K RPM at most of the gears & that's probably he's able to touch 156 Kmph on stock

‪Whit out Musik! Honda CBR 250 R(FI)2011"Aling" Testdrive 1 (originaler Video)‬&rlm; - YouTube

**rmchhetri** · 08-09-2011, 09:50 PM

Originally posted by surya@64 View Post

He has just loosened the lock nut on the steering column. It might be a quick fix for the problem. Just hope there was no pitting on the ball race of the cone. If so...there are 2 solutions...one is to polish the cone set if the pitting is mild...or next is to ask for a replacement...b'cos the warranty holds good.

These are load bearing points & takes lot of abuse in its lifetime in a bike and needs precise settings of torque and good quality cone sets.

Water entry is a lame excuse...for lack of lubrication at the factory.

In case of my ZMA which is 6 yrs old, the entire cone set was re-lubed with silicone grease ( its expensive) by a local mechanic who is a dear friend of mine. Till date there is absolutely no problem.

Well the same treatment will go for my CBR..if the problem crops up...but, still early days for it.

Summary is ...either faulty cone set or bad workmanship...!!

+1
This is usually fix by lubrication. However in the long run, it needs to be replaced. Faulty cone is afterall a faulty cone. If it feels tight again, please get it checked for rusted cone.

**Rahul Rods Tewathia** · 08-09-2011, 09:52 PM

Originally posted by aargee View Post

Much awaited reply

So, you're saying that the top gears are enabled only to cruise; beyond the max torque, on top gear, the bike stays nearly to what top speed it is. If one needs to achieve good top speed, they've to accelerate hard on every gear so that the top speed is increased at top gear -1 & upon top gear, the increased top speed is felt. Am I right?
Right; so that's the reason the pull is less on top gear. So ideally, the bike shouldn't rev past 8.5K RPM (max torque) is it?
This video answers most ppl's agreement as well; nAling revs upto 10.5K RPM at most of the gears & that's probably he's able to touch 156 Kmph on stock

164kmph at 10 k rpm..
from sound it seems to be in 5th gear..can anyone confirm this..

**aargee** · 08-09-2011, 10:07 PM

Rahul - Pls don't quote the entire message; its lot difficult to read as well difficult for people who browse from mobile phone.

**HarishK** · 08-09-2011, 10:09 PM

@ Rahul Rods Tewathia

No way, its in 6th at Top.

**Binoy** · 08-09-2011, 10:18 PM

Last Saturday i hit NH7 just to know the top speed of the bike. I am very much satisfied by the bikes performance as the bike revved freely upto 9K RPM without any difficulty. Redlined the bike in 5th gear(10.5K RPM) and clocked 137kmphr and shifted to 6th. The bike went upto 144kmphr smoothly and took lil time to reach 148. There was a truck infront of me and the heavy windblast made me to slow down. But i would say the bike has the potential to do 155kmphr which i think is the max. I think is a very descent speed for a single cylinder bike.
The best thing i liked in the bike is the cruising ability i was doing 115-120kmphr most of the time and 120-125 without effort. after that you are on the race

. The adrenaline rush after 130 was mind blowing

. At these speeds the bike handled really well and got a fuel efficient around 34-36kmpl

.

**psr** · 08-09-2011, 11:30 PM

Originally posted by aargee View Post

Much awaited reply

So, you're saying that the top gears are enabled only to cruise; beyond the max torque, on top gear, the bike stays nearly to what top speed it is. If one needs to achieve good top speed, they've to accelerate hard on every gear so that the top speed is increased at top gear -1 & upon top gear, the increased top speed is felt. Am I right?

Yes ,....most Tourer or Cruising oriented bikes are geared like that ie., top gear of 0.8..which is good to cruise on top gear all day long and will not touch the redline under normal gear shifting practice.
As a thumb rule operating an engine at 80% or less RPM of red line increases it's life and reliability.

**aargee** · 08-09-2011, 11:32 PM

Originally posted by psr View Post

Yes ,....most Tourer or Cruising oriented bikes are geared like that ie., top gear of 0.8..which is good to cruise on top gear all day long and will not touch the redline under normal gear shifting practice.

But not for C250R; IIRC, its 0.96 or 1.0 at 6th gear for C250R.

Originally posted by psr View Post

As a thumb rule operating an engine at 80% or less RPM of red line increases it's life and reliability.

I understand that point & agree with you. Then how different is the rev limiter w.r.t this 80% limit?

**psr** · 08-09-2011, 11:42 PM

Originally posted by aargee View Post

But not for C250R; IIRC, its 0.96 or 1.0 at 6th gear for C250R.
I understand that point & agree with you. Then how different is the rev limiter w.r.t this 80% limit?

since I do not have the drive ratio details for CBR 250 ,both gear and final drive ratio,I am unable to give a correct answer to the ratio part.
The rev limiter is the absolute limit for the engine, beyond which it may self destruct,and the red line is the start of it to warn of approaching the danger mark.Normally the red line will start about 1,000 RPM before onset of Rev limiter..
Due to mass production techniques no two engines will be alike, and hence the limiter and Redline warning....Some engines with components on max tolerance on most moving parts may die in the red line while the engine with least variance in parts tolerance level will survive repeated,and constant red lining.
just my thought.

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