[Tamir]

R.Q. Welcome to the forum. The forum is old (sinc 2011), so an advanced search in the forum's search engine can be very helpful.
I looked at the picture you downloaded to here. What a beautiful motorcycle.
Check why the lower cover in the tail does not sit well, (1) at the pic down below. Like it is currently sitting it can fall and water may penetrate the electrical connections that are inside. Also you should complete the cover of the swing arm axis, to prevents water to enter the axis, (2) at the pic down below.

The seats have hardened.

According to your picture, it looks like the seat cover was replaced with a shiny material. But regarding the hardened of the seat there is no problem. The ergonomics are such that the hard seat of this model is very comfortable.

Rapid downshift from higher gears sometimes does not happens. I have to step down gears sequentially. Like "6th gear down-clutch release-clutch in-5th gear down-clutch release-...". There are no issues in upshifting though.

"There are no issues"!
This is how you Fast/Rapid downshift on a motorcycle, after more practice it goes fast: (1). Close throttle, (2). Press clutch, (3) Open Close Throttle(Flip throttle), (4) Downshift one gear , (5). Release clutch, ..and so on between gears when downshifting.

 

[Tamir]

 

[Tamir]

Good to hear that you and the mechanic are getting along well and that he is taking good care of your motorcycle
Maybe your mechanic would be happy to demonstrate for you the technique for quickly downshifting?

So correct me if I am wrong, if I am in 6th gear and now I need to downshift to 4th, then I have to go sequentially to 4th instead of clutch in downshift twice then release clutch?

This is what should happen in sequence:
6th gear engaged, then

(1). Close throttle,​

(2). Press clutch,​

(3) Open Close Throttle(Flip throttle), short but measured twist of the throttle. 6​

(4) Downshift to 5th gear,​

*** (See the mark at my following comment)​

(5). Release clutch,​

5th gear engaged, then

(1). Close throttle,​

(2). Press clutch,​

(3) Open Close Throttle(Flip throttle), short but measured twist of the throttle. 5​

(4) Downshift to 5th gear,​

*** (See the mark at my following comment)​

(5). Release clutch,​

NOW the 4th gear is engaged.

The whole idea is to adjust the rpm to the gear you want to engaged.
Another level of expertise is incorporating a handbrake while downshifting.

Also the video above says that its okay if you skip down twice.

Skip on what?
The video above explains to you the pattern of actions for a Sporty / Fast / Quick downshifting, and explains to you that it is possible to downshift several gears in a row according to the same pattern of actions, pattern that repeats itself over and over again for each single downshift.

It's all about skill, if you ride beyond your abilities no amount of skill will help you avoid dangers. The right way to ride safely is to ride according to your abilities and the areas where you feel safe.

 

[Tamir]

*** More explanations:
Between step (4) - Downshifting, to step (5) - Releasing the clutch lever,
you have three options:
A. Accelerate by open the throttle (let's say to overtake a slow vehicle).
B. Adjust the throttle to maintain the current speed (when the situation is not clear, you may be required to accelerate, and you may be required to stop).
C. Leave the throttle closed and release the clutch carefully to perform braking with the engine.

 

[Tamir]

What I heard from part supplier that, CBR250R fan get damaged from center (where it was attached to Fan motor), due to which fan stuck to back side of radiator.

I managed to disassemble the fan into all its parts, also disassembling the fan from the motor axis. There's a very small hex nut in there, and I put it back in place with Loctite. The fan does not touch the radiator at all. The motor is a brush motor. The central axis motor bearings are two brass bearing. I oiled these brass bearing (not because there was noise, but to extend life). I activated the motor with a 9 volt battery(12 volts allowed) and it turned smoothly and beautifully. Then I put everything back in place. (There were photos, but I accidentally deleted them).

And I'm not denying what your mechanic/spare-parts-person saw with his own eyes, just sharing from my experience, what I saw in my radiator fan.

 

[Tamir]

CBR250R fan get damaged from center (where it was attached to Fan motor), due to which fan stuck to back side of radiator.

The fan may have come off the axis. From what I've seen, this connection is very delicate, but also very strong (relative to the forces applied there), but maybe that's what happened to your fan, that the fan came loose from the axis and stuck to the radiator ribs?

 

[Tamir]

I have ordered the fan (requires min. 20 atleast due to parts shortage here in India), once the fan arrive i will open start removal process and update the results with photos.

As far as I understand what you lost there is the small hex nut, you need an M3 nut there (LINK). And you need to check that the D shape axis has not worn out, and if so, then you need to use Green Loctite 680. Loctite or equivalent.

 

[Tamir]

that's great fix. But need precision so that fan rotate staight (perpendicular to motor axis)

I don't know if it's a great fix, but I suggested something that seems good to me, and I think can last a long time. You don't lose the rotational accuracy, and you don't lose the accuracy of the perpendicular to the axis... and you're right, the parts are cheap, and ordering new parts is better (A great fix).
Well, I'm waiting for your pictures.

 

[Tamir]

output around 60W each light,

In relation to the main bulb, there is a significant addition of light
I probably did not install such a rod (In Israel we do not require a front license number).

• 60W refers to the light intensity, or the electrical power?
• Did you use a relay and the voltage comes directly from the battery?
• An addition of 120W (60WX2) is quite significant, will the electrical system withstand it for a long time?

 

[Tamir]

Apology, there is a correction. The power output is not 60w. 45w power is for each individual fog, combined output of 90w. 4500 lumens is the light output.
The lights came with their own harness and switch. This harness is connected to battery. One more thing the lights do not power on unless your bikes engine is running.

It is clear to me that the electrical system can be loaded more than the manufacturer loads in the original state, and it happens that riders load all kinds of electrical gadgets. In my opinion the most common electrical gadget is a mobile phone charger. And loading 90W is not like 120W. It is strange that the manufacturer does not provide us an official Max W figure for electrical accessories.
For ref: For the excess weight that can be loaded on the motorcycle, the manufacturer does bother to provide an official figure.

 

[Tamir]

So i upgraded the bike with aux lights. They are HJG make, cost around 4.5k INR,

The HJG brand that you mentioned is probably only sold in India?
But maybe you can bring us a link here so we can see what its mechanical dimensions are, and the rest of the specifications.
I checked a few options on Amazon and this is what I found:
LINK#1
Size 3", 80W(2x40), 9600Lm, White - Spot Lights OR Amber - Light Bar Spot Flood Combo
140USD + 76USD Shipping

LINK#2
Size 3", 80W(2x40), 8000Lm, Amber/Yellow
25USD + 13USD Shipping

 

[Tamir]

I had read the alternator output to be 340W at 5k rpm?

YES. Now I went over to check for myself, here it is: P.1-11, P.17-3.
It is very nice that you found us this figure, but it is a general figure. It is not clear what happens at idle rpm? And it is not clear how much the original system consumes and how much is available for accessories? The manufacturer does not provide this data.

I can assume, like you did, that the system will hold 90W, but there is no complete confidence in this matter.

 

[Tamir]

Here you go. HJG Transformers White/Yellow LED Fog Lights With Harness/Clamps (rideindiaride.in).

Thanks

When the kit is sold in a set of two flashlights per kit,
then the technical data refers to the total (That's how I understand it):
Total intensity of light: 4500Lm (2250 each)?
Total power: 45W (22.5W each)?
You can measure the current on the HJG electric circuit and calculate the real power?
P[W]=V[V] x I[A]

According to the mechanical dimensions, the HJG is smaller than the ones I found on Amazon, about half the size (height: 4.5 cm = 1.77 inches).
Smaller is better.

 

[Tamir]

Folks, I want to calculate fuel efficiency for CBR. Now as per manual when the last bar starts blinking it means you hav hit reserve capacity and now have approx 2.2 to 2.5 litres of fuel. In my case however the last bar does not blinks continuously atleast for some time. Like if I am waiting at signal the bar stops blinking however once I start riding the bar starts to blink again. Now the bar does blink continuously after few kms or so but its no consistent. So my question is how to reliably to kno that you have indeed hit the reserve?

Hi
YES, The fuel gauge in our model is very inaccurate.
The manufacturer calibrated the fuel gauge according to the "extreme condition".
At urban riding ("extreme condition"), I reached a fuel consumption of about 21 kilometers per liter, and only then, when the last line starts flashing, only then the fuel gauge approach to the stated figure, which is less than 2 liters left in the fuel tank.
At highways riding, when the fuel consumption is 34 kilometers per liter, when the last line starts flashing, there are still about 8 liters of fuel in the fuel tank.

it is what it is.

My recommendation: When riding on highways, keep track of the number of kilometers, and based on that estimate the amount of fuel left in the tank. But those who want to go on the safe side fill up long before the last line start to flash (After all, in any case we make stops to refresh). Getting stuck with the motorcycle because the fuel ran out is the dumbest thing a rider can do to himself (this is from personal experience🤕).

 

[Tamir]

Whats the actual usable capacity? Some folks say out of the 13 litre capacity only 11 litre is usable, the rest is dead storage. Is it the case?

The tank is a 13 liter tank, what causes confusion is that the fuel gauge is very inaccurate (As I explained above - link)

So can i safely assume that when the last fuel bar line starts blinking I have max 21 to 25kms to find fuel station before it runs empty?

Yes
But this is a bad habit that may end unpleasantly.

Anyhow I have habit to fill fuel as soon as the bar starts blinking.

I think that this is a bad habit.

what is your speed and RPM usually when highway riding? I’m curious because of the fuel consumption and how close to mine that may be.

Fuel consumption is affected by two main factors:

1. The rpm (In sports riding the rpm is high, so the fuel consumption will also be high).
2. The speed, because above 70-80 km/h a significant part of the engine's pawer is invested in the resistance created by the air.

In a really relaxed ride, let's say 70 km/h, sixth gear, at ~4000 rpm...I reached a fuel consumption of 39 kilometers per liter.
I rode the way that felt right and comfortable to me (and the engine).
Usually I'm a bit faster, 5000-6000 rpm, at sixth gear, then the fuel consumption is 32-34 kilometers per liter.

It is important to remember: Our engine has no torque and power at low rpm, so we must not let it strain at high gear and low rpm.
39Km/l? I'm not straining it, I'm talking about riding on the plain, with a weight of about 85 kg, no headwind, no dramatic accelerations...etc.