Big Wheels Good?

The thoughts behind 29’er wheels:

Big Wheels

So what are 29 inch wheels and why?

What they are is easy – 2 inch (or wider) tyres mounted on road/hybrid diameter rims. This makes for a wheel which is around 29 inches in diameter, as opposed to the standard 26” inches.

The single biggest reason for using this wheel-size is to make a proportionate fitting bike. 26” wheels only ever became the standard for mountain bikes because the beach cruisers of the mid-70’s, which when converted became the first mountain bikes, used this diameter of rim – they were the only tyres available with enough volume. These were bikes primarily designed for children, and it took over 20 years until someone said hey, these little wheels just feel too small for grown adults. Anyone over about 5’7” (170cm) will generally feel much more proportionate and balanced on a 29” wheeled bike.

In addition to fit, there are a number of other benefits of larger wheels. A bigger wheel makes anything in front of it seem relatively smaller, which means it’ll roll over the top of it more easily. Because they’re bigger, they maintain momentum better.

Of course, there are downsides. The primary ones are weight, and a somewhat limited selection of parts. The parts selection for 29”ers is rapidly growing, tyres, tubes, forks and rims are generally not a problem – we’ll sell you some, plus they are more and more available both online and in your local bike shop. Weight is another issue, this one a bit harder to get around. Of course, a bigger wheel is always going to be a little heavier. However, if lighter wheels were really the only goal we’d be riding super light 20” wheels wouldn’t we? A lot of riders are trading a little weight for better fit and riding performance.

Ultimately the easiest way to see whether they’re for you is to give them a try for yourself.

Gym Biking

God it‘s hard work in a gym compared to being outside in the lovely fresh airoutside i always forget that it is exercise but indoors whew ….. sweaty, looking at all the American GI’s chew steroids and do 200lb dumbell curls ….. so 1hr last night on a bike that doesn’t move with a big lardy arse seat felt as hard as a normal 3hr ride but without the fun.

Still 32km in an hourwish I could do that speed offroad.

Trail on the trail


One of the most critical aspects of defining how a bike rides is ‘trail’. This figure describes the distance between the point at which an imaginary line through the middle of the steerer tube would hit the ground, and the point at which the tyre actually hits the ground. The longer this distance, the slower is response to steering input – and conversely very short trail tends towards ‘twitchy’ steering. As you can see from the picture the more offset (rake) the less trail.

What most people are after for general mountain biking is a fairly happy medium, which is about 70mm of trail.
That can be fine, except a low rake rigid fork on a steep head angle bike does not make for the most comfortable ride. So how to achieve the best of all worlds? Have a long rigid fork with a good amount of rake. Then if you run an 80mm travel suspension fork, it drops the front end, steepens the head angle, and your bike doesn’t turn into the Queen Mary for the sake of a bit of squish. Alternatively this also gives you the option of a longer travel fork slowing the steering up a bit if you’re into the type of riding which might ask for less responsive handling.

Garmin 405 update

Been using the 405 for a while now combination of running and MTB’ing and here are some thoughts.

If you are used to Garmin wrist GPS then this is an easy transition. I had the foretrex 201 (broke kitesurfing) and then a forerunner 205. I also used to use my Polar HRM then it seemed silly that I didn’t have one that did it all.

For kitesurfing and for strange woods the map function (breadcrumb type trails of the 201 and 205 were great) They let me find a 10m gap in a reef to avoid losing fins, let me take a shortcut to get back onto main track when I shagged my wheel and let me find my car once in a weird spooky wood where my internal compass went haywire.

Other than that this is better. Using it only as a HRM it doesn’t quite match something like the Polar where measurement is much more accurate and it measures virtual VO2 MAX thresholds and the like. Going to the gym and then trying to see data afterwards is nigh on impossible in the trailrunner software I am using as you cant import it without gps data.

(the trick around this is to start gps – do a quick 2sec record outside gym – press pause then go in and exercise – you can manually change distances later but it gives you decent HRM recording on screen)

Out on the trail running or biking you can set up different screens to show data you want – you can set 405 to autoscroll through the data if you want or lock it on one screen. The autostop feature I don’t use as I use autolap (every 1km) and when I stop I stop …… the first time I pressed stop and then after stretching I walked back few hundred metres to warm down and HRM started recording again …. threw my min/km pace reading way out.

Afterwards you can review data through History on watch or after download on program this is cool although calories burnt is a bit of an ignore feature as based on distance completely ignoring HRM data and personal stats (unlike Polar which is more accurate based on exertion)


quite comfortable – I found the 201 and 205 a wee bit more comfortable but after 500m I forgot it was on my wrist.

The Strap is good – as unnoticeable as the Polar strap. (EDITED 5/8/9 No where near as comfortable – I have to use sweatbands know to cushion the hard plastic as very sweaty in hot climes)


Lock the bezel if going in the shower as the light (which comes on when you press two fingers on the bezel) goes mad in the shower switching on and off ……. unless you want a disco in which case keep it unlocked.

Trip to Tiree May 2009

just planning a trip to Tiree for mid May. Can’t wait … work in the Middle East or lack of wind when home (as well as moving house) means I haven’t kited since late November …. that’s going to be half a year ….. better pack a 1m trainer kite and a massive twintip then as well.