[mithun]

I've got some queries with regard to Rev Matching.

I know that downshifts will be a lot smoother with rev matching, but...

1. Do bikes with slipper clutches need rev matching?
2. If we ride at sane speeds, do we need to rev match?
3. In city conditions, isn't it just a wastage of fuel?

Tutorial:

https://youtu.be/wMMEYzWpX4E

[ashwinprakas]

Originally Posted by mithun

I've got some queries with regard to Rev Matching.

I know that downshifts will be a lot smoother with downshifts, but...[list=1][*]Does bikes with slipper clutches needs rev matching?[*]If we ride sanely at sane speeds, do we need to rev match?[*]In city conditions, isn't it just a wastage of

You only blip throttle to prevent the rear wheel from steeping out when coming in hot into a corner and downshifting before apex. With a slipper clutch you do not need to bother as the engine braking is mellowed down.

When riding at lower speeds, there is no real gain from blipping, but it's good to practice so you're equipped with muscle memory when the time is right.

I personally don't blip the throttle unless I ride hard, because as fun as it is to ride a small motorcycle fast, the engine braking is sharp on them tiny motors and at times the rear tends to hop or the tyre starts to chirp when dropping gears at a faster pace.

Ultimately its your choice, if you ride hard then better to blip as it does make things slighter for your transmission at the cost of some clutch.

Cheers,
A.P.

[mithun]

Originally Posted by ashwinprakas

Ultimately its your choice, if you ride hard then better to blip as it does make things slighter for your transmission at the cost of some clutch.

Always heard that rev matching would only help clutch plates rather than damage it, right?

[Samba]

Originally Posted by mithun

[*]Does bikes with slipper clutches needs rev matching?

Generally not, but there is no harm in rev matching. Careful release of clutch should take care without rev matching in a motorcycle with slipper clutch.

Originally Posted by mithun

[*]If we ride sanely at sane speeds, do we need to rev match?

It's mainly for fast and aggressive riding. In normal city traffic or low speed riding, controlling the bike is a lot easier. Applying the brakes in a correct way will do the work.

Originally Posted by mithun

[*]In city conditions, isn't it just a wastage of fuel?[/list]

The extra fuel used will be minimal.

I always rev match on highway riding or sometimes even in city riding too (if riding fast).
Mine is a single cylinder, 250 cc bike with short gear ratio's. So with aggressive down shifting the rear wheel tends to lockup. If a downshift is required on the turns of a winding single lane road or on ghat section/hill roads, rev match immensely helps in better weight distribution and help the bike to not lose it's composure. You can maintain the line much confidently.

At the end it helps to reduce less strain on the mechanical's, plus it do increase the safety quotient.

Originally Posted by mithun

Always heard that rev matching would only help clutch plates rather than damage it, right?

With aggressive downshifts without rev matching on a bike without slipper clutch, the rpm will shoot up. That can result in more wear and tear of the clutch due to clutch slippage.

[RiderZone]

For me, revmatching has no other purpose apart from the feel-good factor.

I've paid for a bike with a clutch, throttle, brakes, and some gears, and it feels great to be able to use them all simultaneously in perfect order.

Humans enjoy doing complex tasks, makes them feel not so useless, temporarily.

[NoSugarNoSpice]

Originally Posted by mithun

I've got some queries with regard to Rev Matching.

I know that downshifts will be a lot smoother with downshifts, but...

1. Does bikes with slipper clutches needs rev matching?
2. If we ride sanely at sane speeds, do we need to rev match?
3. In city conditions, isn't it just a wastage of fuel?

The clutch mechanically synchronizes the wheel and the transmission. This is done by disengaging the link(pulling clutch all the way in), then releasing slowly so multiple clutch plates can transfer limited amount of force through each plate slipping against the other via friction and this force is used to match the wheel and engine; finally when they are at same-ish speed you release the clutch.

So if you release slowly only a limited amount of force goes through and the transmission and wheel cogs are fine, for more wear of the clutch plates, or if you rev match, the speed difference is marginal to match.

A slipper clutch allow disconnection of the wheel and transmission end through angled grooves and sleeves in them. Note: This bypasses the clutch plates. So if you're back wheel is faster, the wheel cam pops out of the angled guides which link it with the transmission cam(when the clutch is not pulled in) and it is these guides that take the wear.

While this race track technology can save you from wheel hopping (or in emergency cases ), it does so via slipping the wheel and transmission cams and not the clutch plates, which are designed to slip, wear out and are cheap to replace. I'm sure the manufacturer reinforced the end cams to withstand the extra slippage, but they are going to be more expensive to replace. Race teams can afford this.

So, now that you have the knowledge, you decide what to do.

Personally i skip gears with the clutch pulled in and match for the terminal gear.( lets say I go from 5 to 1 , so it's clutch in, 5 - 4 - 3 - 2 , blip and clutch out)

[ashwinprakas]

Originally Posted by mithun

Always heard that rev matching would only help clutch plates rather than damage it, right?

Na bro.

When you pull in the clutch lever the friction and steel plates are forced apart, and when you give more throttle, the plate that is hooked to the clutch basket spins at a higher rate of speed than the one that is hooked to the output shaft, in effect increasing wear and tear due to friction and heat.

Hence why it is STRICTLY recommended not to rev-bomb with the clutch pulled in, yet we see many guys in events like IBW do exactly that and burn their friction plates clean off.

I tried to search for the video but couldn't find it, but am sure everyone must've seen it, its of a few SBK guys revving their motorcycles and suddenly one of their motorcycles stops pulling even in gear.

Edit:

I'm not sure about stuff they use on the track, but on your standard slipper clutch, the friction plates still do face wear and tear as it says in the name, it literally slips the clutch by using a different design pressure plate with ramps built on them such that under load from the rear wheel they ride up and result in there being clearance between the friction and steel plates allowing them to slip, this works the other way as well with those equipped with opposing ramps, as the load from the engine tends to push the plates together under hard acceleration.

Ari Henning has made a detailed video about this;

The Motorcycle Slipper Clutch: How They Work and Why They're Awesome | MC GARAGE

The clutch at the end of the day is a consumable like brake pads, so wearing them down shouldn't be a matter of concern, if by chance you notice the clutch slipping then simply loosen your clutch cable and ride the motorcycle home, with enough experience you'd know that your plates are toast even before they start slipping as there'd be a change in the lever free play.

This is hard to notice on motorcycles equipped with an adjustable clutch lever, hence why I regard them to be a useless accessory and credit Suzuki for skipping them on the VStrom in spite of some reviewers being unhappy about the same.

Again, nothing to fret as I've ridden 650+ km's back home from Yercaud with a slipping clutch and the motorcycle got me home without much of an issue provided I was sensible with the throttle.

Cheers,
A.P.

[nitro.1000bhp]

Rev matching is necessary while down shifting as it smoothens out the transition between gears and prevents shock load through the transmission. If you have ridden a bike with a clutch on its way out then it will be noticeably difficult to change down gears but by rev matching you can do it smoothly. You can even try clutchless shifting on a healthy bike by simply closing throttle fully while upshifting and blipping the throttle for down shifting. It will mainly save the gears from grinding and in general keep your transmission healthy. You may end up burning some clutch but clutch plates are cheaper than a gearbox any day.

[SVK Rider]

Originally Posted by Samba

Generally not, but there is no harm in rev matching. Careful release of clutch should take care without rev matching in a motorcycle with slipper clutch.
.
.
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With aggressive downshifts without rev matching on a bike without slipper clutch, the rpm will shoot up. That can result in more wear and tear of the clutch due to clutch slippage.

Perfectly described.
Rev matching helps you in keeping the mechanical parts in better condition while aggressive downshifting.

For the motorcycles which comes with slipper assist clutch ideally doesn't require rev matching, however if you do the clutch will last longer.

[IshaanIan]

Whenever you are piloting a car or a bike it is beneficial to keep weight shift in check as that keeps the vehicle ready to take on the vectors that you declare be it braking, accelerating or changing direction. Rev-matching is a part of this. Whether one is going slow or fast it is important; in order to go fast as well as in order to optimally be ready for a change in vectors caused by any unexpected pothole, speed-breaker, car swerving in front, cow crossing the road etc. It is all about efficiency in terms of movement.

[petrolhead_neel]

I have been rev matching on motorcycles for a while now. Most of my riding has been off road, on a small Honda CB110. Honestly, once you get it right, it's the most satisfying thing to do. It adds another aspect of control to you riding. When you are downshifting aggressively, you will get engine braking. When you are rev matching, you have a control over how much engine braking you want. On my bike, with bad, bad brakes, I wouldn't survive without engine braking. With rev matching, I can vary the amount of engine braking as well.

I have very little experience riding motorcycles equipped with a slipper clutch, so I don't know if engine braking becomes completely redundant there. But I'm sure that when I do get a bike that has one, I would still be blipping the throttle on downshifts.

Rev matching also helps you understand a motorcycle a lot more. You get a better feel of the throttle, and more importantly, you understand where exactly the bite point of the clutch is and how it progresses. Rev matching has made me a much smoother rider, with a smoother throttle hand and safe, predictable braking (brakes+engine braking). When I'm riding a motorcycle for the first time, the first few rev matches are a bit rough. However, it is much easier to understand the characteristics of the motorcycles after that.

Originally Posted by ashwinprakas

Na bro.

Cheers,
A.P.

As I understand, the clutch goes through less stress if engine braking is done properly, right? It engages smoother.

Quoting from this article by our very own TVS:

This significantly reduces the difference between the wheel speed and the engine speed and allows for a smoother, jerk free shift into a lower gear. By doing this, you prevent the wheels from fighting against the engine’s compression force, and thus help the engine components save themselves from potential damage. By blipping the throttle, the clutch is also engaged in a smoother manner, where a small amount of slip allows it to engage in jerk-free manner. This significantly reduces the damage done to the clutch components as well.

Learning to rev match and getting it right is a bit tricky though, or so it was for me. That might cost a couple of clutches. But it's all fun!

Thanks OP for this thread, makes for an interesting discussion.

Neel

[Sheel]

Isn't the GB clanky, rear tire stepping out of line if you are braking and going down the 'box if you are not rev-matching?

Blipping while going down [perfectly matching] is so soothing to your senses and motorcycle. Similarly, clutch-less upshifts and downshifts [not while braking]. Once you get used to do them, there is no looking back, you just can't do without. Heck, I try to rev-match on a scooty and then realize my stupidity, it has so become part of muscle memory / system, part of riding.

[Rocketscience]

I do not have the technical knowledge, especially when it comes to motorcycles as others in this thread but i have been riding a motorcycle with slipper clutch (R15 v3) and there has never been a jerky downshift no matter how i drive or how careless or aggressive i'am with the downshifts.

It has come to the point that i hate downshifting in my car because most of the times i get that jerk when doing that and makes me wonder why is such a vital feature missing in cars, maybe because the primary purpose of the slipper clutch is to prevent the rear wheel from locking and that might not be the problem with cars, but it also immensely improves on the shift action which is way smoother and lighter along with buttery smooth upshifts and jerk free down shifts. It is a revelation in my books.

P.S Please pardon my ignorance, in my mind Rev Matching or blipping is done to minimise the jerk while downshifting, something which is totally taken care of by the slipper clutch, if there is any other purpose to it, i'll be glad to learn.

[Red Liner]

Blipping when downshifting has become so much of a muscle memory that it feels weird not doing it. I tried shifting without blipping just for the heck of it and i just couldn't get around it.

[Parishrut]

I ride a Dominar 400. I do rev matching while downshifting almost all the time. The main reason is that I want to build a muscle memory for the critical situations when I need to use it. So even though I do not need it in the city, I still do it almost every time I brake, and will continue till I see myself doing it almost instinctively.

When do I need to really do it or for what am I practicing?
Dominar is a heavy bike with just about decent brakes, and in a straight line, it helps to use the engine breaking. It has ABS, but it works only in ideal road conditions. So on gravel, muddy, and otherwise broken roads, engine breaking helps a lot.
Going into a corner, I need the engine revving around 5k or above, as that makes the bike more eager to turn into the corner, so there I need to downshift again. Running a higher rpm when you're in the corner allows you to reduce speed simply by letting go of the throttle, so that is an added advantage. Plus, if I have to brake more while taking the corner, I downshift again while tapping the brake just a little, which makes the bike even more eager to turn in rather than straightening out.

All the above things, I shall say again, require strong muscle memory. You cannot expect yourself to remember using it just by 'remembering' it. It has to be an automatic reaction.

Additionally, if I am not wrong, rev matching while downshifting helps make sure that your bike's suspension doesn't jerk around due to sudden change in speed. Any jerks in the suspension are not good when it comes to maintaining control.