.: XT660.com - The #1 XT660 Resource :. - Commuter, Adventurer... Racer?

Sometimes, as we age, some vital organs start to wear out, especially when subjected to abuse - such as overwork, exposure to dangerous environments or ingestion of harmful substances. Even if the organ hasn't failed yet, sometimes it's just too risky to wait until it does before taking action - and sometimes the only course of action is a transplant. Of course a transplant requires a donor, and as we all know, often close relatives make the best donors.

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Naturally, a surgical procedure such as this must be performed with the greatest delicacy.

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A sledgehammer would also, metaphorically speaking, be a good implement with which to bludgeon another metaphor to death, so moving on...

This was probably the toughest decision involved in preparation for my US trip - do I trust the engine in the bike? I've had the Tenere for three years now, and put 35,000 miles under its wheels, which combined with the rather pathetic 2,800 miles it covered in its first ten months on the road means it's rapidly approaching 38,000 miles on the clocks. I'm expecting to cover another ten thousand or thereabouts during the twelve weeks I'm in the US.

A well-treated XT660 motor should shrug off that sort of mileage with little concern, and there's plenty of examples on the XT660.com forum which have done just that - some with over 100,000 miles on the clocks. Note the words 'well-treated' - a description I am pretty sure doesn't apply to mine. I'd estimate that I've done something like a thousand miles of rallying or rally training, several thousand more miles of trail-riding, and - crucially - filled the engine with water a couple of times. The first time, while trail-riding on Salisbury Plain, the bike came home on a trailer and had the oil/water drained from the cases as soon as it got home. The second time - during the Cambrian Rally in October, it did another seventy-odd racing miles before I changed the oil (but not the filter) and another day of racing after that before it got any proper attention.

For all I know, the motor might carry on and do the same number of miles again with no issues. Or it might fail one week into the US trip, potentially in quite a remote place.

This gave me three options:

1) Do the minimum - replace the worn-out clutch plates, and probably also the gear selector shaft in the original engine and hope for the best.

2) Do a full rebuild of the engine and gearbox - replacing all the bearings and inspecting everything else.

3) Get another engine.

In the end, I decided that piece of mind was to be found in replacing the engine with a less abused one, and that - having briefly scanned the poor examples of engines available separately, I would look for a good, low mileage example of one of the other bikes which share the Tenere's 660cc motor - the XT660R, XT660X, and the MT-03 - these bikes being somewhat cheaper than buying another Tenere.

Buying a whole bike just for the sake of an engine wouldn't exactly be the cheap option, but it would give me more confidence than buying a 'loose' engine with unknown history, which can't be heard running before committing, and which probably comes without side covers and ancillaries. Really though, it comes down to this - I'm lucky enough to be in a position where it's (relatively) easy to save up a bit more money, but opportunities to spend twelve weeks away from home and work riding a motorcycle on a distant continent are somewhat more difficult to come by.

Just before Christmas, I spotted a promising looking MT-03 advertised on a certain well-known internet auction site. It was in Bristol, but Mrs Uberthumper and I were heading that way to spend Christmas at my parents' house just outside Cheltenham. A trip to the dealer in question on the Saturday before Christmas revealed a late-2007 bike with one owner and just 3700 miles on the clock. Cosmetically tatty, having apparently been ridden all year round by someone who had never heard of ACF-50, but crucially, it had four oil changes recorded in the service book - all done by the dealer the bike was now sitting in. The state of the rest of the bike was just a bargaining tool which allowed me to secure a price of �2500.

We made a second trip down to Bristol just after the New Year to bring the MT-03 home - the ride back home and a couple of trips to work and back allowing me some confirmation that all seemed well in the engine department. It also revealed that the MT is a rather enjoyable little bike to ride - tiny in comparison to the Tenere, low-geared, wide-barred, and with a very forward-biased riding position and weight distribution.

However, with a few long weekends lined up using carry-over holiday from last year, the time for riding the MT was over (for now) - it was time to get on with the engine swap.

Things didn't get off to a great start - it took me two and a half days last weekend to get the old motor out of the Tenere. This was primarily down to a swingarm pivot bolt which was seized into the bearings - and on the XT range the same bolt passes through the rear of the cases. I tried gently tapping it out with a rubber mallet, I tried drowning it in penetrating oil and hitting it with a lump hammer, but in the end it was only by going out and buying a 10lb sledgehammer, then laying the bike on its side that the pivot bolt was finally persuaded to move. My facial expression in the photo above reveals something of how fraught my nerves were by this stage.

The MT came apart slightly more easily, although the challenge in this case was a set of exhaust nuts and studs which had seen a lot of road salt. A bit of careful welding of clean nuts onto the remains of the originals allowed me to get the exhaust off and shortly after, I had the second engine out.

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(Tenere on the left, MT on the right)
A victory of sorts, but with something like ten weeks until the Tenere gets put in a crate and dispatched across the Atlantic, there's plenty more time in the garage to get it all back together.

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