[AbdulRahmanM]

I would like to know what an RR unit is in a bike, please pardon my ignorance, and please delete this post, if its inappropriate.

[Technocrat]

Good Question, an RR(Rectifier & Regulator) unit is the device which is responsible for charging the Battery & hence keeping it in good shape

[chethan.ram]

Thanks Technocrat. This post is very infromative, I even took a print out.

[abhipuru16]

Can somebody tell me if blipping the throttle while downshifting on a bike with the clutch held is harmful or fruitful?
Wouldn't this waste fuel and burn the clutch?
I am actually a double clutching addict when it comes to cars and do it once in a while on my bike as well but didn't know if it is recommended for bikes.

[Visaster]

@ Technocrat -

It was a nice read up. It would like to add an suggestion.
Why don't you add some picture to each part you have described to make things easier for the person.
It would be of great help if you can re edit your whole post with some picture of each part as and when you describe. It would not take much time for you.

Thanks for the help.

[DevilsOwn]

abhipuru: Let me put it this way: Would you rather have your rear wheel spin out uncomfortable if at higher speeds or when you need to downshift while braking (no blipping) or would you rather have a smooth shift with barely a slight jerk without the sliding, however minimal it may be (blipping).

Also, fuel efficiency lost is negligible due to blips for downshifting and I personally have never heard of fried clutches as a result of the same.

To put things simply, blipping or no blipping, make sure your rear tyre ensures the engine knows what rpm its at with reference to actual speed Its that mismatch which causes it to slide (which is rather exciting, but causes more damage than a simple blip which is comfortable and good on the machine).

Unless of course you use a slipper clutch in which case ^^^ is moot.

Quick shifting is a different story.

[ksanjee]

May be we could add Slipper Clutch [back torque limiting]

Used for aggressive [high speed] down shifts without having to blip the throttle to match engine revs with wheel speed..

Some high end models superbikes come with it in stock trim..A lot of aftermarket vendors for ducati...STM, Bucci etc..

Krishna

[ksanjee]

Quick Shifter - clutchless shifting with ignition cutoff

[anandkenkare]

Could someone clarify what is a lambda sensor in an Enfield Classic 500 and how do I ascertain whether my bike has one?

[n_aditya]

Originally Posted by abhipuru16

Can somebody tell me if blipping the throttle while downshifting on a bike with the clutch held is harmful or fruitful?
Wouldn't this waste fuel and burn the clutch?
I am actually a double clutching addict when it comes to cars and do it once in a while on my bike as well but didn't know if it is recommended for bikes.

The process of blipping the throttle, pulling in the clutch, dropping a gear, releasing the clutch, doing all this while braking on a motorcyle (also applies to cars) and repeating this cycle again if needed is called rev matching.

In simple terms dropping a gear while braking transfers quite a bit of load onto the engine and onto the drive wheel (rear wheel in case of bikes). If revv matching is not done, the sudden load on the engine causes the wheel to lock up momentarily (sometimes longer) causing loss of control leading to a fall or a crash.

Revv matching ensures that the transmission and engine revolutions are matched (any mismatch and the above happens) ensuring minimal load onto the engine.

This technique provides much needed engine braking and also when executed well, the engine is in the right gear and in the powerband to exit out of the corner fast.

Slow in and fast out is the rule so do all the adjustments such as braking, gear shifts etc, well before the turn, roll off the gas (dont close it abruptly and completely) look into the turn, accelerate mid corner progressively and through the turn.

Hope i have not confused you further

See this : Heel-and-toe - Wikipedia, the free encyclopedia

There are tons of videos on you tube for revv matching which will help you understand and execute it.

Originally Posted by anandkenkare

Could someone clarify what is a lambda sensor in an Enfield Classic 500 and how do I ascertain whether my bike has one?

Lambda sensor or O2 sensor is placed on the header pipe usually mid way from the exhaust manifold and expansion chamber / cat-con. It is present in FI engines.

The ECU uses the lambda sensor to obtain important info such as AFR (air fuel ratio) and correspondingly retards or advances timing (in advanced engines many other critical parameters and functioning of the engines internals is adjusted) to optimize engine performance depending on air quality, fuel quality, etc.

See this and this.

[anandkenkare]

Thanks for the info. The bike I bought here in Muscat does not have one. They also sell the Europe/U.S. spec bikes here which do have a lambda sensor but are significantly more expensive.

[VijayAnand1]

Excellent stuff. I was always struggling to find the difference between scavenging and back pressure. There.

Cheers!
VJ

[vrprabhu]

Originally Posted by n_aditya

The process of blipping the throttle, pulling in the clutch, dropping a gear, releasing the clutch, doing all this while braking on a motorcyle (also applies to cars) and repeating this cycle again if needed is called rev matching.

In simple terms dropping a gear while braking transfers quite a bit of load onto the engine and onto the drive wheel (rear wheel in case of bikes). If revv matching is not done, the sudden load on the engine causes the wheel to lock up momentarily (sometimes longer) causing loss of control leading to a fall or a crash.

With experience and an ear tuned to the engine revvs, you can actually drop a gear or shift up, just by blipping the throttle - without using the clutch at all.

With a little practice it can be mastered. Comparatively easier to do on a four stroke as against a two stroke, as the power delivery in latter was more immediate when dropping a gear.

(It just struck me just now, haven't had a snapped clutch cable since more than 10 years - against two instances in the late 90s).

Recollect a similar article on two wheeler driving techniques in Overdrive long ago.

Also, there were (are?) a couple of bikes without clutch - one was TVS Jive and the other Hero Street. As much as I can recollect these bikes had a rotary gear system.

So clutch is an aid for gear shifting, and I have also not had heard for any clutch burning due to downshifting and blipping. (Lack of oil must be the primary reasons for clutch burn, if it is a wet clutch).

AFAIK, slipper clutches are more of torque limiters for high power engines, to aid the driving of the back wheel.

BTW, abhipuru16, I thought that double clutching was a thing of the past, after the synchromesh gears became the standard?

Just a small two cent worth observation from my side :-)

[n_aditya]

Originally Posted by vrprabhu

With experience and an ear tuned to the engine revvs, you can actually drop a gear or shift up, just by blipping the throttle - without using the clutch at all.

Clutchless shifting is easier while upshifting.

While downshfting, load is transferred onto the engine and gearbox. Clutchless downshifts are not advisable since it can cause unnecessary stress on the engine and gearbox and in the long run it can harm critical components. It can be done but not advisable.

[ku69rd]

Originally Posted by n_aditya

It can be done but not advisable.

That necessitated the introduction of Slipper Clutch Phenomenon into the world of Superbiking. So enjoy the ride on such bikes without bothering about pulling in clutch for upshifts and downshifts.