Direct drive turbos

richiegwy

I'm looking at getting a direct drive turbo and considering some of the elite range.

Can anyone share experiences of the volano or turbo muin b+?
What are the differences between both in terms of ride feel and resistance adjustability?

tompo1

I've got the Turbo Muin Smart B+. Can't really fault it.

It has a 6kg flywheel compared to the 3kg flywheel of the Volano. This means it should be smoother when riding at lower cadences. Also means resistance is greater.

Resistance on both turbos is not adjustable. Resistance is progressive which means it is dependent on the gear being used and gets harder the faster you ride.

The Turbo Muin is very stable in use. Haven't seen the Volano but it does not look as stable.

I got mine from Mantel (shop in France) last Xmas. It was considerably cheaper than anywhere in England. Price included delivery. I ordered on boxing day and it was delivered two days later.

You will need to buy the Misuro sensor separately. Again it pays to shop around. I got mine from Ribble who were cheapest of those shops which had stock at the time.

richiegwy

What kind of efforts do you do on it ( power / cadence)? What gears are you in typically doing these.
I want to get something that will cover my efforts best and don't have the opportunity to test the, out beforehand

tompo1

I do quite a variety of efforts. I think I have a 12-27 or 11-25 cassette on the trainer and 52/36 on the front of the bike. All efforts are done on big ring and are typically about 100 rpm at top end the block.

Also do a lot of low cadence efforts in a bigger gear at about 60 rpm. To give some idea of resistance I struggle to do 45-50 rpm using the biggest gear.

richiegwy

Thanks topmo1.
When your doing those efforts what kind of power range are you in if you don't mind sharing?

tompo1

Difficult to say because power is dependent on resistance which is dependent on gears used.

For example, I did a short session yesterday doing 5 min intervals at 60, 80 and 100 rpm. At 60 rpm I was averaging just under 400 watts but at 100 it was down to about 280.

BenderRodriguez

I have tried both the Volanao and Muin, and now have a basic Muin. The Volano was pretty unstable and offers much less resistance. The Muin is a beast. You can spin in a low gear but the resistance ramps up quickly with increasing speed, especially above 300 watts, which comes up at about 25.9 km/hr, meaning about 70 Rpm in 50 x 17, or 103 Rpm in 34 x 17.

The Elite sensor runs off the fan and estimates cadence indirectly. I had Polar Bluetooth speed and cadence sensors, and although the magnet on the fan triggered the speed sensor it runs about 17 times faster than the flywheel, and you can't adjust a Polar M450 to the tiny wheel circumference required to get a true reading. (The minimum being 1000mm.) To overcome this I got a 20 x 3 mm thick, 4.5 kg pull magnet from first4magnets.com (who are also on Amazon) and stuck this to the flywheel with strong double-sided tape. Now I can get true speed and cadence readings and link to Zwift, FulGaz and so on with no problems, or record a session with my Polar M450.

The Muin is built like a tank and pretty 'fluid' to ride. Be aware, however, that it has a very low inertial load. Perfect if you want to train for climbing (which is what I specifically bought it for) but no so much something like time trialling or track racing, as the muscle recruitment will be different and less event-specific adaptation will occur. (The testers favourite has been the LeMond, but these don't seem to be in production at the moment.)

The power curve for the Muin can be found here:

http://www.powercurvesensor.com/cycling ... er-curves/

Some speed versus power tables for the Muin:

https://docs.google.com/spreadsheets/d/ ... edit#gid=0

BenderRodriguez

tompo1 wrote:

I do quite a variety of efforts. I think I have a 12-27 or 11-25 cassette on the trainer and 52/36 on the front of the bike. All efforts are done on big ring and are typically about 100 rpm at top end the block.

Also do a lot of low cadence efforts in a bigger gear at about 60 rpm. To give some idea of resistance I struggle to do 45-50 rpm using the biggest gear.

Hardly surprising, given that 52 x 11 at 50 rpm requires about 420 watts on the current Muin. (Those with a serial number under 30,000 have a less steep power curve.) In the same gear 100 Rpm requires about 3,200 watts! :shock:

On the current Muin, if you are doing 100 Rpm in 52 x 23 that is still 377 watts, and in the 21, 484 watts!

This is the formula needed to calculate the power needed to turn the Muin at any given speed:

P = 5 + (1.02 x V) + (0.001 x V x V) + (0.015436 x V x V x V)

Where:
P= power in watts
V= speed in km/h

By the way, programs such as Zwift and FulGaz take into account the steep power curve of the Muin, so your calculated speed is true to life, and in turn much higher on the flat than you would get with a direct speed reading using something such as a Polar M450.

richiegwy

BenderRodriguez wrote:

I have tried both the Volanao and Muin, and now have a basic Muin. The Volano was pretty unstable and offers much less resistance. The Muin is a beast. You can spin in a low gear but the resistance ramps up quickly with increasing speed, especially above 300 watts, which comes up at about 25.9 km/hr, meaning about 70 Rpm in 50 x 17, or 103 Rpm in 34 x 17.

The Elite sensor runs off the fan and estimates cadence indirectly. I had Polar Bluetooth speed and cadence sensors, and although the magnet on the fan triggered the speed sensor it runs about 17 times faster than the flywheel, and you can't adjust a Polar M450 to the tiny wheel circumference required to get a true reading. (The minimum being 1000mm.) To overcome this I got a 20 x 3 mm thick, 4.5 kg pull magnet from first4magnets.com (who are also on Amazon) and stuck this to the flywheel with strong double-sided tape. Now I can get true speed and cadence readings and link to Zwift, FulGaz and so on with no problems, or record a session with my Polar M450.

The Muin is built like a tank and pretty 'fluid' to ride. Be aware, however, that it has a very low inertial load. Perfect if you want to train for climbing (which is what I specifically bought it for) but no so much something like time trialling or track racing, as the muscle recruitment will be different and less event-specific adaptation will occur. (The testers favourite has been the LeMond, but these don't seem to be in production at the moment.)

The power curve for the Muin can be found here:

http://www.powercurvesensor.com/cycling ... er-curves/

Some speed versus power tables for the Muin:

https://docs.google.com/spreadsheets/d/ ... edit#gid=0

What do you mean by inertial load and how it relates to time trailing. I will use it mainly for intervals (from 20 sec high gear efforts to 5 min efforts) and blocks of 15min at certain power zones. I managed to borrow someones turbo main to try and most efforts I am in mid cassette and small front ring. Tried to turn 53x11 and could barely get past 55 rpm.
My fear is the volcano will not be strong enough for big gear, low cadence efforts or the main B+ will be too powerful

BenderRodriguez

richiegwy wrote:

What do you mean by inertial load and how it relates to time trailing. I will use it mainly for intervals (from 20 sec high gear efforts to 5 min efforts) and blocks of 15min at certain power zones. I managed to borrow someones turbo main to try and most efforts I am in mid cassette and small front ring. Tried to turn 53x11 and could barely get past 55 rpm. My fear is the volcano will not be strong enough for big gear, low cadence efforts or the main B+ will be too powerful

Despite what some believe, pedalling is not just pedalling, as there are significant differences in muscle recruitment patterns under different load conditions.

When travelling on the flat at speed a condition of high crank inertial load exists. In effect if you stop pedalling it will take a long time to slow down and stop, and the variations in speed as one goes through the power stroke versus the 'deadspots' will be very small. Conversely, when climbing one will be riding in a condition of low crank inertial load. That is, if one does not keep the pressure on the cranks there is a tendency to slow down rapidly or 'stall' and the variations in speed through the pedalling stroke will be much higher, so one effectively has to repeatedly accelerate against the gradient. This is most noticable when grinding up a steep hill when over-geared.

The muscular system automatically responds to these variations by changing the way the muscles are used and the motor units deployed. On the flat one will tend to pedal with a series of short, sharp 'jabs' at the pedals, whilst when climbing there is usually a tendency to sustain the torque for longer, with a lower peak torque value and also with a 'rounder' pedalling style, pulling and / or pushing through the dead spots much more than happens on the flat. One side-effect of this is that most people will automatically reduce their cadence when climbing as opposed to riding on the flat, even if generating the same power. Another effect is that the variations in speed will be reduced, so there is less need to keep making micro-accelerations on each pedal stroke.

Trainers also vary in the degree of inertial load they have, and most of them have much less inertial load than when climbing, never mind riding on the flat. For example, the Muin might have a 7kg flywheel, but due to the huge amount of resistance it generates, the flywheel is never spinning very quickly.

The degree to which a trainer's inertial load affects the degree of transfer to riding on the road depends a lot on the rider and their particular balance of Type 1 to Type II muscle fibres and so on. Many riders who train on a low-inertia trainer, when their target event requires them to perform under conditions of high inerta (such as testing) find that their trained 'turbo power' is around 10% or even more than they can generate on the road. Conversely, someone who is well trained to ride on the road in a flat time trial might find it hard to generate anywhere near the same number of watts on a low-inertia trainer as they can when riding, typically saying that it feel like 'riding in sand' or similar.

These differences are a major topic of discussion over on the Time Trialling forum, and many there have found that the higher the inertia of the trainer they use, the better their 'turbo trained fitness' translates to the road. On the other hand one might expect that the fitness developed using a low inertia trainer, such as the Muin, will transfer better to climbing than if a high inertia trainer was used. Again, much depends on the physiology of the individual.

I wouldn't be worried about a Muin being 'too powerful', just gear down!

Here is an article on the effect of inertial load on climbing versus time trial power.

https://cyclingtips.com/2013/09/climbin ... -affected/

More discussion here:

Inertial load is the next main differential factor when comparing indoor and outdoor training. Without going into too much detail, when we ride outdoors, we have the inertial load of a bike and rider moving at some speed, plus that of the wheels turning. If we stopped pedaling, our rear wheel doesn't suddenly slow or stop turning, we would coast for quite some time. On many trainers however, since we are not moving, the inertial load is much less and confined to the rear wheel spinning and any small flywheel that the trainer has attached to the roller. When you stop pedaling, the wheel slows and comes to a halt relatively quickly. Some are worse than others.

Now what happens is each scenario feels quite different to ride, muscle activation is different, the neuromuscular demands are different and these can be enough for some to make power production much harder.

http://alex-cycle.blogspot.fr/2009/01/t ... ining.html

thomasmorris

^ Good post.

I train on a cyclops mag trainer with a powermeter. It was cheap.

However, I put out more power on that than I do on the flat outside (about 10%). I thought it was because I've come from mountain biking where inertial speeds climbing are very low, however it could just be genetic.

I used to look at people moto-pacing or doing hill reps and just think 'why don't they just do those effort as normal intervals on the flat?'. But since having the power meter on and off the turbo trainer I can see what a difference inertia makes to power output, and how this type of training isn't just about the intervals, but also training for the inertia.

Off topic, but there was a time when I thought there's no such thing a 'natural climber' or 'natural tester', and it's simply about getting the best W/kg or W/CdA as possible. However, now I can see how two riders the same weight, CdA and nominal FTP may perform differently due to how they deal with high / low inertia.

BenderRodriguez

Good point about the impact of doing motor pacing, as this will also create different inertial load conditions than putting out the same power at lower speed, even if the difference is likely to be less than that between climbing as opposed to riding on the flat. Perhaps all those old school riders who used to work out behind motorbikes, such as Merckx, were on to something after all!

The importance of inertia is also why simply duplicating the naturally lower cadence of climbing by using a big gear on the flat doesn't really duplicate the demands of climbing. In fact, spinning at speed as one would on the track, climbing and testing on the flat in a big gear an intermediate cadence all create different muscle recruitment patterns, and, for many riders, need specific training. Reducing cadence 'to simulate climbing' is manipulating the wrong variable. In effect the cadence adopted is a side effect of other factors.

Another issue is that most physiological studies ignore the effect of inertia, so a study concluding that there is no such thing as 'round pedalling', or no benefit to be had from pushing though the 'dead spots' might well have reached a different conclusion if the inertial load used in the study was different.

There is also the influence of the level of work being done, as studies have showed that when working near one's threshold one will use a different muscle recruitment strategy than when just bowling along at a low power output. Typically, one will tend to reduce the maximum torque value but increase the time torque is applied during the pedal stroke as the effort increases. The degree of fatigue also has a strong influence on just which motor units are recruited. As they say, specificity of the imposed demand is central when it comes to training the neuro-muscular system.

When it comes to training the cardio-vascular system, almost anything will do the job - even running or cross-country skiing. Similarly, even if you aim to be be riding mountain sportives, riding the track is still worthwhile as it will boost your VO2 max and develop your cardio-vascular system, even if the effort is not specific enough to maximise your climbing ability.

Again, the degree of benefit one will get for any specific form of training depends to a large degree on the physiology of the individual, which is why knowing yourself is so important and why following a training programme set out by a coach who has no idea of your own physical peculiarities might not prove to be maximally effective. On the other hand some riders seem to be able to cope very well with whatever demands are place on them, and can transfer from one sort of effort to another very well.

BenderRodriguez

By the way, the importance of training demand-specific muscle and motor unit recruitment patterns is becoming apparent in other sports too. For example, I read a paper a while ago that did a multi-factor analysis of the hill running performance of runners versus cross-country skiers. What they found was that the runners - unsurprisingly - went very fast given the limits of their VO2 max and so forth when on the flat. However, when running uphill the primary determinant of who performed the best was simply VO2 max, with high V02 max skiers outperforming runners who, on the flat, would have left them in the dust. So, even for runners who do tend to do some hill training, doing the vast majority of their training on the flat made them fast on the flat, but apparently did not develop the optimum muscle recruitment patterns (often reflected in measures of 'efficiency') needed to deal with the different task of running up hills, even though it still involved 'running'.

svetty

Not sure there is much evidence to support this TBH. It certainly isn't mainstream exercise physiology thinking.....

thomasmorris

There are quite few published articles linked through the articles bender has linked. I've not read them however. But maybe there is evidence here?

To be honest, I think home training on high end trainers with a power has been fairly niche until recently.

From reading forums and talking to others it seems it's not uncommon to see a difference in trainer power versus road power. Maybe we'll get more studies as more people experience indoor - outdoor discrepancies.

This is the only theory that explains why some people are higher and lower outdoors than in (most other theories explain why you'd be less powerful inside, but struggle to give a reason for the opposite).

BenderRodriguez

Svetty wrote:

Not sure there is much evidence to support this TBH. It certainly isn't mainstream exercise physiology thinking.....

Actually, there is a growing body of evidence that pedalling is not 'just pedalling', and that muscle and motor unit recruitment patters are affected by a wide range of factors. For a good introduction to the topic see:

"Electromyographic analysis of pedaling: A review.  Journal of electromyography and kinesiology. 19(2):182-98 · January 2008 By Hug and Dorel.

https://www.researchgate.net/publicatio ... g_A_review

Also:

'BIOMECHANICS AND ENERGETICS OF UPHILL CYCLING: A REVIEW', by Fonda1 and Šarabon. Kinesiology 44(2012) 1:5-17

http://hrcak.srce.hr/file/124396#

Also:

Crank inertial load affects freely chosen pedal rate during cycling
Jensen and Hansen Journal of Biomechanics 35(2):277-85 · March 2002

http://www.researchgate.net/publication ... ng_cycling

Also:

Arkesteijn, Marco and Hopker, James G. and Jobson, Simon A. and Passfield, Louis (2013) The effect of turbo trainer cycling on pedalling technique and cycling efficiency. International journal of sports medicine, 34 (6). pp. 520-5. ISSN 1439-3964.

http://www.radlabor.de/fileadmin/PDF/Po ... ._2012.pdf

Abstract

Cycling can be performed on the road or indoors on stationary ergometers. The purpose of this study was to investigate differences in cycling efficiency, muscle activity and pedal forces during cycling on a stationary turbo trainer compared with a treadmill. 19 male cyclists cycled on a stationary turbo trainer and on a treadmill at 150, 200 and 250 W. Cycling efficiency was determined using the Douglas bags, muscle activity patterns were determined using surface electromyography and pedal forces were recorded with instrumented pedals. Treadmill cycling induced a larger muscular contribution from Gastrocnemius Lateralis, Biceps Femoris and Gluteus Maximus of respectively 14%, 19% and 10% compared with turbo trainer cycling (p<0.05). Conversely, Turbo trainer cycling induced larger muscular contribution from Vastus Lateralis, Rectus Femoris and Tibialis Anterior of respectively 7%, 17% and 14% compared with treadmill cycling (p<0.05). The alterations in muscle activity resulted in a better distribution of power during the pedal revolution, as determined by an increased Dead Centre size (p<0.05). Despite the alterations in muscle activity and pedalling technique, no difference in efficiency between treadmill (18.8±0.7%) and turbo trainer (18.5±0.6%) cycling was observed. These results suggest that cycling technique and type of ergometer can be altered without affecting cycling efficiency.

Etc...

BenderRodriguez

By the way, as I said earlier, the time trialling community are really waking up to the importance of inertial load, and there are a lot of threads discussing this topic on the time trialling forum. One poster, 'TarmacExpert', has also calculated the kinetic energy of a range of trainers:

Some rough figures for the kinetic energy, in Joules, of different turbos when riding at 240W are:

Muin 300J
Kurt Kinetic standard flywheel 600J
Kurt Kinetic pro flywheel 2800J
Tacx resistance 4 1100J
Tacx resistance 5 700J
Tacx resistance 6 500J
Lemond Revolution 2000J

Outdoors 80kg rider+bike 45kph 6000J

mrb123

Fascinating thread.

BenderRodriguez

Many experience variations is power output in conditions of different inertial load, even when the difference is relatively small, as when a flywheel is added to a trainer. Few seem to have any idea about what is going on though! For example, see this rider who trained for a long period on a Kurt Road Machine turbo, then added the optional flywheel:

I got the Pro Flywheel as a Christmas gift this year and installed it in early January. The past 5 weeks I've done 3-4 rides per week on the trainer with a mix of vo2 max and lactate threshold intervals, and endurance rides (very similar to what I have done the past few winters on the Road Machine without the extra 12 lb flywheel).

I've noticed that my workouts seem harder than normal with the Pro Flywheel. I struggle to hit my target power, but can do it. HR is what is should be, but something just feels different. At first I just chalked it up to being out of shape, but I took the 12 lb flywheel off and repeated some of the same workouts and found them to be noticeably less in RPE. Especially with workouts like 5 x 5:00 @ vo2 max power, my legs feel much more trashed after riding the same exact power output as without the Pro Flywheel or out on the road. As a side note, my power output on the road and on the Road Machine sans Pro Flywheel are essentially identical. It's not a cooling or trainer adaptation issue.

I've always believed that "a watt, is a watt, is a watt", but what could be accounting for this difference? Has anybody else experienced anything like this? I thought the Pro Flywheel would make the "feel" of riding the trainer better, but it seems to have done the exact opposite.

http://forum.slowtwitch.com/forum/Slowt ... _P3778918/

BenderRodriguez

To add to the debate, Grahame Obree's views run pretty much counter to the prevailing wisdom that - for many riders - training on a turbo with a high inertial load transfers to flat road testing better than using a low inertial load trainer. He advocates the opposite and also advises using a pedalling style that most people would only adopt when climbing. Again, this could just be a reflection of Obree's particular physiology, which means that he found that this approach works best for him. The fact that he tended to use huge gears might also be a factor. For example, Obree used the slowest ever cadence to break the hour record at 92.9 Rpm, a full 10 rpm slower than most everyone else.

There is just one more thing to be done to your turbo to make it conform to the ‘Obree Way’ of training. This is optional but advisable. Every commercial turbo comes with a fly-wheel on the opposite side from the magnetic unit. I ask you to remove it or have your local shop remove it for you. It may be worth telling them that it is most likely fitted using a ‘left hand thread’. The reason for this is that pedalling is as complicated as a swimming stroke and certainly not an up and down affair. Removing the flywheel will help train an all round more efficient stroke. I explain all in the section about pedalling, but for now, trust me, and get rid of it!

...The first point of the stroke is when the cranks are straight up and down (top dead centre). This is the most neglected part of the stroke and conventional thinking is that you have to wait until your legs have bowled past to 30° or 40° before applying a proper standing force on the pedal. This is where we must learn to use the most neglected muscle in cycling, the vastus medial – the muscle you kick a football with. You have to start at the top by kicking that football. On the upstroke leading up to this point you should have allowed your ankle to drop so that your foot is at an acute angle to your shin (hence the need for free movement).

This is not Zofseu man explosive kick, but because your ankle is dropped, you roll onto where you would normally put the force down and use the available movement in the ankle to employ the calf muscles as well as the muscles in the thigh to drive the pedal stroke downwards. This enables you to use the entire half circle of the downward stroke. At the start you will need to do this in slow motion to get to grips with it, but if you think L—O—N—G (as in the stroke) it will keep you focused on distance of stroke rather than force during the long downstroke. Don’t try to put one burst of strength at the middle point. This is about using just a little less force than a stomping style but delivering it evenly over a long stroke. Because the peak force is less than before there is the advantage that fatigue is also less, even though more power is being outputted…

PEDAL STROKE TECHNIQUE

• Start with you heel dropped with the cranks vertical
• Kick that football and follow through with calf and thigh muscles
• Think L—O—N—G stroke
• Kick with your opposite leg just as you go to pull for the upstroke
• Slightly rock onto each pedal

BenderRodriguez

Just a quick update on the basic Muin versus the Muin B+.

I have found that the power readings I get on the Muin from a Polar Bluetooth speed sensor picking up a magnet fitted directly to the drive wheel and using the formula I gave earlier are very, very close to what I would get on the road.

Reading around, many seem to find that the Misuro B+ sensor is nowhere near as accurate, at times over-reading the power one would expect from the published power curve and formula by as much as 30%. Some also find that the cadence reading is unreliable which, as it is estimated indirectly, is perhaps not a surprise.

This inaccuracy is such that there is talk of Zwift disallowing 'wins' by those using the Misuro B+ sensor. Apparently, altering the recommended wheel diameter correction factor can make the figures look more realistic, but to get the value correct one would probably have to calibrate the value using a power meter. Some users are suggesting that the Misuro B+ is calibrated to the power curve of the previous version of the Muin, which had a less steep power curve.

Overall, despite the hassle of having to fit a magnet to the drive wheel, doing this does seem to be the best option, and also allows one to use any computer or app that is compatible with the sensor fitted.

http://www.elite-real.com/en/forum/turb ... resistance

http://www.elite-real.com/en/forum/turb ... -b-no-data