Team-BHP (https://www.team-bhp.com/forum/)

-   Motorbikes (https://www.team-bhp.com/forum/motorbikes/)

-   -   Honda CBR 250R : Answers to some commonly asked questions (https://www.team-bhp.com/forum/motorbikes/118403-honda-cbr-250r-answers-some-commonly-asked-questions-11.html)

RIDING, I suppose

Not sure, if I've understood things right, but there're lot & lot to post, it's not one simple scenario as the clutch can be engaged in 100 different occasion.

Define excess? 5K RPM downshift? 6K RPM downshift? 7K RPM downshift? 8K RPM downshift?

Like I said, quantify them because, 5K isn't excessive + excessive is an abstract term & to each his own.

10W-40 is THICKER grade of engine oil than HMSI supplied 10W30; From my EXPERIENCE of using 10W30, 300V 10W40 Factoryline & Shell Ultra 10W40 (again, there're two variants, pls be specific about the MRP, cover of the can etc to distinguish them). Have found Shell Ultra to be slightly superior than Motul 10W40 which is way ahead superior than HMSI 10W30 engine oil.

But again, if I were you, I wouldn't recommend switching the engine oil until the warranty expires; not that Shell Ultra, Mobil, Motul or any god damn thing might harm, but, something goes wrong, putting things back to place becomes mighty expensive.

10W stands for 10 degree Celsius & Winter; 40 degree means, the engine oil's viscosity level is like 40C when the engine temperature is 100C. The viscosity level of the oil is very important because, higher the temperature, lower becomes the viscosity level & when the viscosity level is down, the oil looses its capacity to lube there by causing damage to the engine. Hope you were able to understand.

Pls go through this - http://www.upmpg.com/tech_articles/motoroil_viscosity/ & http://www.driverstechnology.co.uk/oils.htm

Ok, here goes. The brake pads are the right ones but once I fit in the Galfer pads, there is absolutely no space for the disc itself! So I took it to the service center (again there was engine noise) and asked the technician to check - he also tried and said an idea would be to remove one of the older pads - put in the Galfer pad and do the same for the other once the pads are a little worn. I didn't find this a great idea but have gone ahead and done this.

And update on the engine noise - got a shim changed - now the engine note is beautiful! Ah good to have the baby back in perfect shape.

Thanks n_aditya and Akhilash95

Reason being...the oil from master cylinder has to be bleeded & the pistons to be pushed back using C-Clamp (with the backside of screwdriver if experience)

Not a good idea :( Anyway, next time when I'm in Bangalore, we'll catch up & look into the Galfer. I'm 101% confident that it works. Did you order the Galfer from the UK site that I mentioned few pages back? They know clearly as what pads work & which don't. Hopefully your supplier hasn't given you unfit brake pads & hence the mention.

Sanjay - So did you complete 32000 Km? Reason to ask is because, it isn't 2 years since CBR 250R is launched for the warranty to expire.

About the brake thing, brake is not to be applied when clutch is engaged. That's not the right way to brake to keep the wheel & engine in sync.

Change the oil filter as per recommended intervals in the service manual. I usually change air & engine oil filters with every service as it costs way too less.

Since you're in Chennai, would you consider joining this group - https://www.facebook.com/groups/ChennaiCBR250R/

Is it ok to upshift without pulling in the clutch ?(except 1-2 as there's neutral in-between resulting in a not so smooth).
Eg : running in 3rd gear @ 6k rpm
1.preload the shift lever
2. Hands off throttle for a moment
3.at the same time shift to 4th gear
4.continue throttling

Does it cause any problem overtime ?
Does it reduce the life of the transmission or engine ?

Perfectly yes to destruct the motorcycle :D

On a serious note, I tried once & I couldn't shift; thought I'll break the gearbox & then didn't attempt it.

Needless to say, otherwise clutch would've not even been a part of automobiles...universally isn't it?

Rest assured if done correctly, it doesn't. There is no evidence that it does if done correctly. You may scour the internet for more dope on it.

Few friends do clutch-less downshifts as well & frankly, I haven't tried doesn't mean it isn't possible.

One of them is a member here pulsurge. He has done close to 30K on his 250R & the other's CBR is close to 50K.

This isn't limited to the 250R BTW as you know.

You have got the basics right & you won't master it in a attempt or two. And no, your engine won't get into trouble if you are doing it the way you have mentioned.

Thanks :-)

Interesting; I was under the impression that it's not possible to shift the gear without clutch, like cars. Let me talk to Pulsurge & find out or try out tomorrow.

Tried to shift without clutch this morning & I was amazed that it was quite possible; something that I thought isn't possible did happen. Now to the details...

- If you rev the engine, it becomes extremely hard to shift the gears, be it upshift or downshift
- Something in the range of 3-4K RPM is quite easy; but again, not consistent; what I mean is, the gear shifts are sometimes feather touch, sometimes with a little loud clank; sometimes have to be pressed little harder, sometimes not
- There's no definite pattern relating the RPM, speed with feather touch gear shift. I'd this in my Rx where I can be sure that at certain RPM's the gear WILL be smooth shift, but that's not the case here or may be I'm still learning with CBR

No clanks please. Use clutch then.

We all shift just shy of the red-line & it is all smooth.

It shall get bad, IF you aren't riding hard, that is riding in commuter mode. You have to keep the throttle wide open after shifting. This is what I have experienced.

Scour the net, watch You Tube videos & practice. Nothing like it.

Thanks :)

http://www.team-bhp.com/forum/techni...ml#post2354649

I think lots of us have done clutchless gearchanges in an emergengy (clutch cable failure).

Regards
Sutripta

Yes, guess that was it. And he kept insisting that the silencer needs to be removed for fitting the back pads. Don't think that is required.

No, I am certain it is nothing wrong with the pads - they are the right ones also - confirmed from the seller before placing order and the site you had mentioned.

Have done several times on my old Rx when the cables broke, but I don't like to ride without clutch, not that because, I cannot, but, I feel like hurting the poor vehicle.

Anyway, last evening, I tried a few times shifting gears with highrevs; the result were mixed again, sometimes I was able to shift smoothly like feather touch, sometimes not, had to try multiple times. May be I need to press little harder.

Crazy mechanic; try to change your ASC. Absolutely not required.

Can you post a pic pls? I'm sure it's a direct fit on Nissin or may be we should talk as what went wrong & where. I'm 100% sure it's a direct fit.

My two cents: Please don't mix a two-wheeler gearbox with a 4-wheeler's. Motorcycles have a sequential gearbox, i.e., you HAVE to go through the sequence of gears unlike cars where you can jump gears. Hence, one can very safely make clutchless shifts. The trick is to keep the RPM at the right level in order to use the pre-loaded lever to slot into the next higher gear. Clutchless downshifts are possible too, although upshifts are easier to master.

As Sheel has pointed out, youtube is a good place to learn.

Actually it is even easier to make clutchless gearchanges, esp. downshifts, in a car compared to a bike. The sequential shift pattern in a motorcycle is not relevant in this regard, the lack of a well defined neutral between every pair of gears is. Cars have a well defined neutral position.

Regards
Sutripta

P.S. Ever wondered why in a DSG, downshifts take longer than upshifts?

Anyway before it becomes a controversy, here's my take on clutchless gearchanges:
Can it be done - Yes
Will it damage the gearbox - If perfectly done, IMHO, no.
Should one do it regularly - No. Because doing it perfectly 100% of the time is very difficult. And when you don't get it right, you are damaging/ causing extra wear and tear on the gearbox.