Wow! Helluva video that - had me on the edge of my seat for a moment ot two!
Ends well as well.

Isn't it TV material?

Now, in the Good Ole Days, they used to put a small hole in the lowest point of exhaust systems (well, the Japs did) to let the water out......
Lucky they don't do it now, would have destroyed the best scene in the video!

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TTR250 - London to Cape Town

I have a 94 TA since 95 and have known many with TA´s and AT´s during the years since then. Been on Transalp lists since way back, forums. Deti´s Transalp Pages, Transalp.de etc.

I cant remember ever having heard of this problem at all, something must have been changed, parts missing, wrong type or incorrectly installed is my first thought. This should not be an issue on a normal Transalp. CDI´s on pre 94 models are known to fail, rear wheel bearings wear out early on many, speedo drive gear often fail and on early models; I believe 87-88 starts to use oil at some point. Apart from that, bomb proof bike if normally looked after.

I looked at the pictures; your chain is way too tight if it is on it´s side stand. If you have ridden with a tight chain you should both feel and hear it easily and that will most likely cause premature wear on parts. it says 3,5-4,5 cm chain slack, 3,5 is actually too tight, stay at 4,5, its an off road bike. Better a bit loose than a bit tight.

You say it is an 88 model? Maybe the engine is but the rest of it is not. Can that explain anything irregular? It looks as if you have an early Transalp engine (black) installed in a 97-99 Chassis. Double front discs, swing arm with rear disc brake, fairing is 94 or newer. Silver coloured rims (96->) etc. Do you mean you have a 98 TA with an 88 engine?

Its a strange problem, maybe a mismatch between the Transalp parts you have there?

Anyway, good luck!

It's a 88 engine and chassis/electrics with everything else off a 98 bike, so your explanation of various colours of rims/engine/number of brake disks etc is all correct.

The swingarm was put into the chassis by a proper bike mechanic including new swingarm bearings.

As explained earlier, I believe the issues were caused by a too tight chain, fuct sprocket carrier bearing and dubious cushdrive rubbers, combined with a non-textbook refitting of the back wheel following a tyre change. Also, the bike was ridden very aggressively due to the condition of the terrain being covered. I believe only a fraction of Transalps get the abuse I've given mine.

As far as burning oil, all 3 of my Hondas do:
* a 87 TA (very high miles: maybe 100k miles?: up to a litre for 1000miles, but only if I ride with rpms over 5000. I just never do an oil change, just top it up),
* a 88 TA (the bike in question: probably high miles, this bike gets it all: oil top ups and oil/filter changes)
* a 95 AT (50k miles, top ups and changes...)

So I ride everywhere at 50mph/80kmh: best fuel consumption and least oil consumption (the TA is on 4500 rpm and AT 4000)

A mate in the trade gets me oil at cost price which is substantially less than retail.

I'm now back home in the UK and the bike is parked in Mongolia until summer 2013. I can't do any more diagnosis/checking in the interim. I'll take all the parts listed previously and hope for the best. If that fails I'll weld the new sprocket on. If it all goes tits up, then the bike only cost me gbp 500, so who cares.

It'll be fine, it's a Honda.

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Brighty's website: TheBrightStuffDotCom

CURRENT RR WITH REGULAR UPDATES: The Wife Takes on Chlamydia: A South American Retrospective

Judging by the side wear on the front sprocket, the sprockets are out of line, check with a straight edge/string.
If you weld the sprocket on, you do not need to weld All the sprocket to the shaft, just put a couple of blobs on to stop the sprocket coming off, do it so it can be ground off later, try and weld on top of the splines, not in the valleys.It shouldn't take much of a weld to stop it coming off.

I know this is an old thread but as people are still searching/finding this and other sprocket advice via search I'll comment.

Your sprocket was installed wrong way. Many sprocket threads at xrv.org.uk give this really bad advice to install pattern sprocket with flush side towards engine and shoulder side away from engine (as on your schema). Genuine sprocket for newer XL600V (more spindles on shaft) has rubber shoulder on both sides, that means there is shoulder on engine side plus another on other side. So for pattern sprocket, shoulder must be towards engine as it has shoulder only on one side. That is the only way pattern sprocket can maintain same chain line as genuine sprocket.

If you install flush side towards engine, chain will be off about 5-6 mm towards engine and it will start rubbing against engine case. See your own photos, chain has already grind against engine case there as it was too close.

My theory about why retainers are wearing out quickly with pattern sprocket installed shoulder outside (wrong way): Since chain is now over 5 mm towards engine than designed, sprocket starts to put more pressure on the outer retainer as chain guide was designed for another chain line. Rear sprocket and chain guide are not on the same line with sprocket installed wrong way, they are trying to move the sprocket away from engine, putting additional pressure on outer retainer which wears out quickly. Chain guide also wears out.

It seems that the known Transalp issue of output shaft spindle failure may be mostly caused by lower quality (loose fit) pattern sprockets installed wrong way.