New Wheels! New Wheels!

The time has come to replace the wheels on my Spa Cycles Tourer, and replacing any component on a bicycle presents the choice of sticking with what has worked before, or upgrading to something perceived as better. However, upgrading carries the unknown element of potential failure, in the past I have found that some 'expensive' parts have been less robust than the 'cheap' parts they are replacing.

The existing wheels were built by Spa Cycles; Rigida Sputnik rims laced to Deore hubs with 36 spokes front and rear.  The rims are known to be heavy, but also have a double wall feature so that they will not fail catastrophically.  I have covered 20,000km with them in all weathers and they have stayed true.  They have carried my weight (which has varied between 80 and 100kg) and have also carried a full touring load.  These are clearly the most reliable choice and it would be sensible be to replace like-with-like.

When something has been very reliable though, and when it is known to be heavy, I am left wondering if they were a bit over the top for my uses.  Checking the Spa Cycles website I found I could go for a lighter touring rim, the Exal LX17.  I am told that it is the rotating weight of the rim which is the hardest to move, so reducing this and keeping all the other components the same should make sense.  Both the Exal LX17 and the Rigida Sputnik have the same double walled safety feature.

Weight of rim for a single wheel: Rigida Sputnik is 690g, Exal LX17 is 575g.

Based on this thinking I wouldn't have to compromise safety, I would have lighter wheels and I would find out over time whether they would last as long. To be fair to the Rigida Sputniks; they have not actually worn through yet.  I believe there is still another couple of thousand kilometres left in them, but with some long overnight events on the horizon this year I wanted to be safe and make the change now.

The second question was about what hub to choose.  If I was going to upgrade the rims, would I be able to afford to upgrade the hubs too?  I know that I could have re-used the hubs, but I have already serviced them numerous times and I was in the mood for an upgrade.  I was limited to a choice of hub with a 135mm OLN (Over Lock Nuts), this is the gap in the frame where the rear wheel sits.  There are some truly bling components out there, the famous stuff comes from Chris King in the USA or Hope in the UK, beautifully designed and engineered, but far too rich for me at the moment.  Also I really wanted something I could service myself if necessary, but looking at the Shimano techdocs website to try and work out which components are best (and why) leads me into a maze of serial numbers and minor variations of product detail.  The Deore LX range does appear to be targeted at the trekking tourist and the XT range appears to be more mountain bike focussed. Even with side-by-side printouts of the Deore, LX and XT rear freehubs I struggle to understand which is "better".

So after this research I have decided: Exal LX17 rims laced to Deore LX hubs with 36 spokes on the rear, and (why not) 32 spokes on the front.

Well.. I had decided.  Until someone sent me a link to these wheels on the Rose Bikes website...

Shimano Deore LX Hub Dynamo, the DH-T670-3N model, on the front and a Deore LX freehub on the rear.  I had always thought that hub dynamos were really expensive and I had ruled out any idea of buying one.

Mavic describe their A719 as "Bombproof and High Endurance" and also as "the benchmark in trekking and tour... all conditions".  Well, they would wouldn't they!  But no data on weight and the the image of the cross section has none of the safety features of the Rigida or Exal rims.  The problem I now have is that I like the Exal LX17 rims, but I like the idea of the Shimano Hub Dynamo.

The dynamo hub question is complex: Is it worth the extra weight and the extra drag from a dynamo hub to offset the need to carry spare batteries on an overnight bicycle ride?  This article by the CTC's Chris Juden went a long way to convincing me that I would like to have the dynamo hub and light: Hub Dynamos PDF

Further research suggested that current dynamo lights are designed to meet German traffic regulations, with a good beam shape, a cut-off to protect the eyes of oncoming motorists, and of course there is the consideration that the lights are ready whenever I need them.  I then discovered that one of the B&M lights has a USB port, so I could keep the little garmin device alive longer without the spare external USB battery pack I use.  The decision was taking shape in my heart, and on the "Brief Encounter" my mind became made up looking at the quality of the light and dynamo on Dean's bicycle.

I had to sell some items to make room in my wallet for this, but as soon as the funds were available I placed my order.  Rose bikes ship from Germany, but it is hardly a problem as the parts were with me three days later.  Here shown with some of the packaging removed.  Time to start work on swapping the wheels over and testing the lights.

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