I bought a new speed sensor for the road bike as I'm planning to keep the Polar for that generally but I foud that Garmin do a quick release bike mount for the 305 whihc also comes with a velcro strap to replace the original unit strap, it is very much aimed at triathletes but I have no intention of running off the bike at the minute but I find the current strap gets uncomfortable after a while and the unit starts to dig into my wrist bone, there is no way I would wear it on my wrist on a bike. So I thought it may be worth trying out the strap and mount and duly ordered it from Amazon in the middle of the week, it arrived on Friday morning which meant I could replace the strap for the weekend's trail race. The kit composed a velcro strap with a plastic mount on it, a plastic mount for the bike, a tool to prise out the spring pins on the watch strap, some spare spring pins and some zip ties. The important bits:
The mount is actually quite neat which I was pleased about but due to the shape of the forerunner there was no way it was ever going to mount to a stem, I like it on the stem on the MTB as I feel its more out of the way in the event of a crash, I will also be interesting to see how it sits on the riser bars too but I'll find that out soon, this one is going on the road bike first. The strap is wide and inital impressions are that its comfortable, plastic mount means that the unit itself is held more proud of my wrist than before so it should hopefully solve the wrist bone irritation. It will be getting a full try out at the Garburn race tomorrow. The downside of that is that the unit looks even bigger on my wrist than before but I've gotten over the "beam me up Scotty" looks of the thing, I like using it.Getting the springpins out to remove the original strap was a bit of a faff and one pinged across the lounge somewhere, the hoover will no doubt find it soon enough, however I just used one of the spares that came wth the mount and the strap was on. The unit now clips onto the plastic mount on the strap and is pretty easy to get off though my one concern is how long the plastic will tolerate this.

I'll see how I get on with the strap at the Garburn race. If I decide to put the mounts on all three bikes and I think its an even better idea for MTB then it seems Garmin don't do the bike mount without the strap, now I think a spare strap is a great idea for me with my propensity for losing things (still can't find my remote car key!), I think two spares is a teensy bit excessive and will just encourage me to be careless with it. I'm currently planning a recovery road ride for my legs on Sunday so will hopefully try the bike mount out then.