Silverstone Int’l 14 Apr 2014

silverstone-intlWaking up on a sunny Monday morning, the portents for a great track day were looking good. I had also arranged to have a day’s instruction with Andy Taylor of Real Roads fame. We first met on a track day at Brands Hatch back in October 2012 when he instructed me on what was to be my first track day in nearly 20 years.

This track day at Silverstone on the International Circuit was my first of 2014 in the UK. This was a three group track day with two novice groups and one inters/fast group. I booked into the Inters group although I was slightly apprehensive about being out with much faster riders. After arriving at the track, my suspicions were confirmed as I spotted a race team unloading two bikes from a large van.

Soon after arriving, I met Andy in the paddock. He should have been ridding his new GSXR750 track bike which had recenty replaced his CBR600RR, however that bike was out of action due to a fairing mix up. The supplier had sent an incorrect fairing which Andy only discovered after painting it and trying to fit it to his bike! As a result, he would be riding his road going Fireblade instead. As we were chatting, he mentioned its Yoshimura exhaust pipe, however I didn’t really understand the significance of that conversation until later in the morning.

This was to be my first track day using tyre warmers as Andy had kindly brought a spare set with him for me to try. I was dubious of their benefit as I normally allow one to two laps to get the tyres up to temperature before trying to up my pace. However I could really feel the difference the warmers made as I left the pit exit. The tyres just felt both different and better than they would have when cold and that meant that I could open the taps up after the first three turns through the Village complex leading on to the Hanger Straight.

A a result, I’m now a convert! Even running a set of Michelin Pilot Power supersport tyres, I think it’s worth the hassle of tyre warmers as you probably get an extra lap each session because you can get on the pace that much faster. You also don’t get sucked in to continuing to ride at a slower pace for the whole session after your warm up laps.

There were to be four 20 minute sessions before lunch and three after lunch. Our plan was to ride independently for the first and last session of the day and for Andy to eiher follow or lead for the five intermediate sessions with a debrief after each one. The morning’s rider briefing seemed to drag on longer than usual – I suspect this was because of safety concerns with two novice groups on the day. In the event, this meant that we were still scrambling into our our leathers immediately after the briefing as our session, the first of the day, was about to start. For one reason or another this seemed to be a pattern that would repeat itself throughout the day – I seemed to be constantly coming from behind trying to get out on track on time!

SilverWingPitThe first session was great. It was brilliant being out on the fantastic Silverstone International circuit in such glorious weather. My plan for the session was to try and brake later for the corners and not to fall off! In terms of pace I was definitely running near the bottom of the group and it was quite humbling to see just how much faster and smoother the quicker riders were. However, rather than being intimidated by them, I found that they were generally considerate in their passing manouvres and I really enjoyed being out on track with them. I also doubt that I was much of an annoyance to them because they flashed past me so quickly before disappearing into the distance.

AndyNoiseProblemI figured Andy would do his own thing the first session, but he seemed to spend that a lot of that first session behind me. I could tell this because of the sharp bark from his Yoshi exhaust. As we pulled in to the pits at the end of the session, Andy was hauled over by a marshall who wanted to noise test his bike. Andy had ridden the same bike at Brands a couple of weeks earlier and had passed a static noise test at just 102dB. Silverstone’s marhall asked Andy to run his engine at 7000rpm instead of the usual 5000rpm – so no one was particularly surprised by a reading of 113dB! Normally an incident like thing is an automatic ban from the circuit, but because of the extenuating circumstances of having passed at another circuit with a reading of 102dB, Andy was allowed to try and sort the problem out. This involved him removing the can, and trying different baffles – a time consuming process that cost him two hours and two missed sessions that morning.

I was left to my own devices for those sessions but was helped along with advice from Joe, one of Silverstone’s own instructors. He is a great character who obviously has quite a soft spot for the Triumph describing how he used to thrash race prepared machines on his totally stock Daytona 675. He also gave me some good advice regarding lines for each corner, reminded me to relax and bend my arms and upper body more, and to trust the bike’s tyres in order to try and use more speed through the faster Abbey and Stowe corners.

My first session riding with Andy instructing was the fourth of the day and took place just before lunch. With all the hassle that Andy had been through in the morning trying to get his bike out of track, I think that he was mostly happy to follow, watch my mistakes and understand where he could help me make some improvement in the subsequent sessions.

We took our time over lunch, spending the free Silverstone £10 (US$16) lunch vouchers on some decent food. In fact this is the first time that I have visited the canteen but it won’t be the last as there is a huge array of good food choices on offer. We both grabbed a sandwich being mindful that a large plate of pasta is not the most approriate food for an energetic afternoon’s riding. We were having such a good time over lunch that I strolled back into the garages to see most of the group exiting the pit lane. I quickly found my helmet, removed the tyre warmers and raced out of the garage leaving Andy scrabbling to get his bike ready too.

Silver-ValeOver lunch Andy had really made a point of stressing that I needed to take charge of the bike, and make it go where I wanted rather than leaving it up to its own devices. He did this rather forcefully as he felt that this was one of the areas where I was really letting myself down. He argued that doing this and using more of the track (on corner entry and exit) would reduce the radius and allow me to take the faster corners at a higher speed.

After the session, Andy was smiling. He hadn’t been sure whether to hang back and wait for me to come past or whether to go for it and try and catch me up on track. In the event, his racing instinct must have taken hold because he went for it finally catching me on the final lap of the session. He seemed impressed because he found it harder to catch me than he thought and because he could see that the conversation we’d had over lunch had actually begun to sink in.

The next session Andy followed for the first part, led in the middle of the session and followed again at the end. You can see the session in full below. Also included is a data overlay showing speed and acceleration/braking g-forces using data from my RaceChrono app.

After returning to the pits, Andy congratulated me on a good improvement in my riding. I think he felt that I finally belonged in that group as I was now running a similar pace to some of the other riders. RaceChrono confirmed that I had nearly made a 2 second improvement in my lap time compared to my last outing on the International circuit last October. Something really clicked that session and I finally really felt like I had made a significant step up in my riding. Reviewing the footage, I can see that I still need to move around the track more and make better use of all the available space. This is (yet?!) another area that I will be working on the next time out.

In the final and seventh session of the day, I think that tiredness finally began to take its toll as my riding was more ragged than the previous session, and I suspect that my lap times were slower as a result. Why ‘suspect’ instead of ‘know’? Because I seemed to miss the start of virtually every session that day for one reason or another which meant that I either forgot to switch a camera or external GoPro microphone on, or start the RaceChrono timer app before leaving the pits. In fact the only session I actually managed to time successfully was the penultimate session of the day and its data can be seen in the video above.

Hooking up with Andy and riding with him again was great. He is a really good instructor and I think that he helped me identify some key problem areas which improved through the day and he has given me something simple and concrete to work on at my next outing on the same track in two weeks time. Although I’m not yet riding at a level I’d like to be at, he did comment that my riding now and when he first met me over a year ago are like night and day. Going forward, he suggested focusing on making incremental improvements in the following areas:

  • Widening the turns by deepening the turn in point and avoid the temptation to dive for the apex too early. Similarly letting the bike run out wide on the exit for more speed and a reduced turn radius
  • Remembering to bend my arms more to lower my upper body and to allow it to lean further off the bike
  • Use more of the available lean angle on the tyres – there’s still another 6mm (1/4″) of my rear tyre available before hitting its edge
  • Having more confidence in both the bike and especially the tyres so as not to scrub off more speed than necessary on the entry to faster corners like Stowe and Abbey
  • Getting on the gas earlier to drive through corners like Club earlier and harder

Overall I’d rate this track day as brilliant – the combination of riding with Andy and being at Silverstone in glorious weather was fantastic. Silverstone run great and friendly track days with really helpful instructors and at a track whose facilities are among the best in the UK. Hopefully I’ll also have another opportunity to ride with Andy again later this year.

Garmin GLO vs QStarz 818XT Part 1

After hearing reading a lot of positive feedback on the Garmin GLO, I decided to get one and compare it with my QStarz 818XT which has worked perfectly for me over the past year. My primary interest in the GLO is to see whether it can provide faster updates and more accurate positioning information.

Garmin GLO and QStarz-818XT

Garmin GLO and QStarz-818XT

The Garmin GLO and QStarz 818XT are bluetooth GPS receivers and can be used to provide a much more accurate GPS signal for race track timing compared to the built-in GPS found in most mobile phones. The GPS in a mobile phone won’t typically update its position more than once a second (1Hz) while these units can update at up to 10 times per second (10Hz). I use RaceChrono to record my lap times and if you are new to this, you can find out how RaceChrono works in this detailed post on using RaceChrono.

Both of these bluetooth GPS devices are similar in size although the Garmin is slightly slimmer and longer than the QStarz-818XT. The battery in both is good with each device giving a minimum of 12 hours on a single charge – enough for a full day on track. In fact the battery life of the QStarz is actually a lot better than the GLO, supposedly lasting up to 40 hours (although I haven’t actually proved that).

Size and battery life isn’t the only difference between these two units – the technology used by them for determining their position is also different. The QStarz-818XT only uses the US GPS satellites in order to determine its position while the Garmin GLO uses both the US satellites and the Russian GLONASS system. This makes the GLO’s hybrid technology fairly unique in the market compared to most other makes and model of GPS unit, and it’s what gives the GLO an edge over the QStarz in terms of outright accuracy.


This image is from RaceChrono showing the satellite information when connected to the QStarz-818XT. You’ll notice how the GPS unit has locked on to 7 satellites and is reporting its horizontal position accuracy as 1.1 – this is an excellent value indicating a high degree of precision.

The DOP values range from 1 to more than 20 where 1 is ideal, 1-2 is excellent, 2-5 good and values over 5 less increasingly less accurate . DOP stands for dilution of precision and you can get a detailed description of DOP values from Wikipedia.

Garmin GLO

Because the Garmin GLO is able to use both the US GPS and Russian GLOSNASS satellites for determining position, it has access to more satellites at any point in time which in theory allows it to determine its position more accurately. Under the satellite settings it reports its horizontal DOP as 0.7 which means greater accuracy than the 1.1 DOP value reported by the QStarz. This makes sense because the GLO is reporting a fix from 14 satellites compared to the QStarz’s 7 satellites.

To get these screenshots of RaceChrono, both GPS devices were placed side by side with each connected in turn to RaceChrono to grab the two screenshots. The two readings were therefore taken within a few minutes of each other and so should not really be affected by the fact that the satellites will have moved slightly during the test.

Startup times and operating speed

My feeling is that while the Garmin GLO gets its first fix a little faster than the QStarz-818XT there really isn’t that much in it, and since both devices lock on to satellites so quickly – you’re never stuck waiting for the first position fix. Both devices were also really easy to connect to RaceChrono running on my Android phone.

One major difference is the position output frequency of the devices. The QStarz is able to operate at 1Hz, 5Hz or 10Hz while the Glo only operates at 10Hz* – this means that it will send an updated position fix (over bluetooth) ten times a second or every 1/10th of a second.

While the QStarz-818XT is also able to operate at 10Hz, it will not output as accurate a signal as it will at 5Hz where the DGPS (differential GPS) capability can be enabled. In fact, the general consensus is that it is better to run the QStarz at 5Hz because although you only receive a new position fix five times a second each fix will be more accurate fix that the ones received at 10Hz. I’ve written another post that describes how to configure the QStarz-818XT to operate at 5Hz.

* When running RaceChrono with some Android 4.0+ devices using the Garmin GLO, the output frequency can switch from 10Hz to 5Hz and sometimes even down below 1Hz. This isn’t a problem with the GLO so much as a problem with the bluetooth stack in Android 4.0 and above. The device is sending too much data too fast for the OS to be able to process because some genius programmer decided to rate limit the receiving side of the Android bluetooth stack!

First impressions

My first impressions of the Garmin GLO are good. The unit is smaller than I through it would be, and it operates well with RaceChrono. It ships with a USB and a separate cigar charging lead which is good. The one thing I don’t like though is the On/Off switch which is too easy to knock. You could pack the unit away and find that the battery flat when you needed to use it because the On/Off switch got pressed by mistake in transit.

The QStarz-818XT is a solid performer. I’ve never had any problem with my unit. It locks on to satellites quickly and operates flawlessly at 5Hz with the DGPS enabled. I like the long battery life and the fact that the On/Off switch requires a more positive sliding action to switch it on or off which means that it’s unlikely to be switched on by mistake.

In my next post, I compare the operation of these two bluetooth GPS receivers on the race track.