Rev matching for motorcycle riders
One of our most popular articles in on the art of rev matching, which is a skill which can be even more relevant for motorcycles than cars. This article is loosely aimed at track riders but is also relevant for the road to improve your smoothness and comfort – it also sounds great and is easier on your transmission. If you ride with a pillion and you knock helmets when changing down gears, this technique could be the answer.
When slowing to a halt this tip is less useful.
Bike engines can sustain very high engine speeds – the Honda CBR250 for example could safely rev to 19,000 rpm before it was restricted to 18,000 due to Japanese regulations. When rapidly changing down through the gears while slowing down, as the clutch is released there is a tendency for each shift to force the engine speed to rise significantly, and this can generate a serious amount of engine braking at the rear wheel. A degree of engine braking can be useful when slowing down, but in extremes can lead to jerky forward weight transfers and unsettle the bike – the last thing you need when entering a corner. In extreme cases the rear wheel could lock unless your bike is fitted with mechanical methods of preventing this such as a slipper clutch. Be aware that relying on a slipper clutch to smooth your gear changes is a really bad habit to get into.
On a bike, riders are encouraged to move through the gears to keep the engine operating in the power band. As bikes have sequential gearboxes, the risk of selecting second gear from sixth at 80 mph then letting the clutch out is low, however rev matching as each gear is selected will lead to a smoother experience for the rider, and will improve your confidence on the track.So how do you do it?
Consider this scenario – you’re approaching a corner and are starting to set up the bike. You position the bike correctly, and need to apply the brakes and select the correct gear for a good exit. For simplicity, we’ll assume the correct gear is one gear down. You apply the brakes and get the bike to a suitable entry speed to the corner, and before you turn in you select the lower gear. At this moment, it’s most essential the bike is settled and stable – so a jerky gear change should be avoided at all costs. Sure, you can smooth out a change by slowly letting out the clutch – but this isn’t really a something that’s going to shave seconds off your lap time.
If you’d like to learn more about cornering, click here In principle, rev matching is simple – as you select the gear and before you let out the clutch, blip the throttle to raise the engine revs. With practice you’ll be able to match the revs to the speed of the road and the gear, until one day it will be instinctive. You know you’ve nailed it when you let out the clutch and there is no noticeable forced rise in revs and the associated weight transfer. As you get better you’ll be able to combine all of the actions into a fluid series of events – but as you’re learning it may be easier rather than a ‘blip’ to elevate the revs to a sensible level and hold the throttle there while you smoothly release the clutch – it really depends how rapidly you hope to shift, and how smooth you want to be.
Rev matching while braking
If you’re a confident track rider and you’re starting to brake later into corners, you’ll need to find ways of shortening the process of positioning the bike, braking, changing gear and turning in. One of the best ways of doing this is to combine the braking and gear changing stages into a single fluid phase. It can be very rewarding to get right and can shave seconds off your lap time.
The key is to make sure you can comfortably operate the brake and the throttle simultaneously with your right hand. To do this, you might need to adjust the reach of the brake lever, or possibly buy a replacement. Finger position is really a matter of taste, most riders use their index and middle fingers on the brake and their ring and little fingers on the throttle. Priority should be given to the brake, so make sure you have a good grip and are unlikely to slip off (think potholes).
Now assuming you are familiar with rev matching, all you need to do is rev match while on the brakes. This does require a fair amount of coordination, and if your gloves aren’t particularly flexible or thick it can be tricky to get right. With practice you’ll be able to smoothly flick down through the gears and let out the clutch without a jerky forward weight transfer – the goal is to be as smooth as possible.
Depending on your preference and your bike, this can be combined with block shifting to compress the time taken to be fully prepared for the corner. In this case, block shifting means changing down multiple gears without letting the clutch out until the required gear is engaged. Some bikes (and riders) don’t react particularly well to this, do worth experimenting and find out what suits your style.
Please note, that with all motorcycle techniques, real life tuition is much more valuable that learning the theory online – it’s great to understand the principles, but please don’t attempt anything you are not comfortable with unless you have been provided with the necessary training and advice. If you disagree with any of the topics we discuss, please stick to the style of riding you’re happy with. This is arguably one of the more advanced motorcycle riding techniques, and as a mistake could affect your braking please be sensible and seek tuition.
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