Transalp-Freunde Deutschland e.V.

Technik: Advice needed in Mongolia: Transalp output shaft/ sprocket/ retainer problem, Urgent

• chris am 25.8.2012
  Hallo Transalp-Freunde!
  Ich bin Englaender, speche und verstehe aber auch Deutsch. Hoffentlich koennt Ihr mein Problem/Englisch verstehen und mir Ratschaege geben. Vielen Dank in voraus.
  
  I'm nearing the end of my 7 week trip through Central Asia, Altai-Russia and Mongolia.
  
  I have a problem, I think, and would be really grateful for suggestions/ comments/ possible solutions. It is also urgent as I fly home to England next weekend (today Sat 25th Aug, flight Sat 1st September). I was hoping to leave the bike in Mongolia to continue my trip into eastern Siberia next summer, 2013 (preferred choice). If necessary, however, I can freight the bike back to the UK from Mongolia, but would need to set things in motion very quickly.
  
  The bike: 1988 pd06 XL600v Honda Transalp, unknown mileage (I'm the 12th owner!), but anywhere above 50/80 thousand miles/kms. On this trip the bike has done 8500km/5000miles, about 50/50 pavement/gravelMudSand. The front sprocket is OEM Honda 15 tooth, rear steel aftermarket and chain expensive DID 525 118 link vx. All 3 are still in good condition, I believe. Please see images below.
  
  I reached my destination Ulaan Baatar, the capial of Mongolia a week ahead of schedule, so decided to take a ride south to visit the Gobi desert. Yesterday morning (8300km/5000miles into this trip), just before setting off I noticed the damage to the sprocket cover (see image: I removed the plastic centre circle, it was still 2/3 attached to the cover). This damage would have happened very recently as I definitely would have noticed a gradual issue.
  
  Before leaving for the Gobi, I replaced the sprocket retainer (number 1) with a new spare (number 2). It last precisely 200km/120miles! See image.
  
  I rode as carefully as I could back to Ulaan Baatar today. Before setting off I also loosened the chain a bit more too. Retainer number 3 is already half worn after this further 200km/120 miles!
  
  The front sprocket does “wobble” a little on the shaft.
  
  How/why did this happen? I believe the chain tension wasn't too tight. The output shaft is IMHO in good condition (much better than the one on my 1995 Africa Twin...).
  
  What's the solution?
  
  1. Weld the sprocket onto the shaft? (not a problem, the bike is cosmetically very nasty and only really worth gbp600/us$1000/euro700, if that). This can be done locally, if I can find a competent Mongolian welder who understands English or German.
  
  2. Replace the output shaft? The would require a full engine rebuild, for which I don't have the expertise. Finding a competent English/German speaking mechanic in Mongolia will be a challenge! Also the parts would have to be sourced and imported. I can ship the bike back to England where I know a very reliable mechanic, but I can't justify the cost (it would be 1500euro shipping for a 700euro bike and that is before paying parts and labour.)
  
  3. Just put on a new front sprocket? I don't have one with me, but could easily bring one with me when I would return to Mongolia in 2013 for my Siberia trip. I'd also bring a job lot of new retainers with me.
  
  4. Or? Over to you!
  
  FWIW, I am sending this email using the wifi at the Oasis Guesthouse. Rene and Sybille, the owners, are currently out of town, but back on Wednesday. I'm hoping to be pro-active from Monday (27th August) morning onwards.
  
  Several images are below that will hopefully help solve my problem.
  
  
  Retainers from left to right
  1 lasted 8000km
  2 lasted 200km!!
  3 is half worn after 200km!!
  4 is new (for comparison)
  
  
  
  Chain tension
  
  
  
  Chain tension
  
  
  
  Chain pulled off rear sprocket, still v good condition, IMHO
  
  
  
  Retainer number 3 on sprocket, before setting off this morning.
  
  
  
  Output shaft looks Ok to me, I've seen a lot worse on my Af Twin that has about 1/3 missing off each tooth
  
  
  
  See above comment
  
  
  
  When I pulled over for a pee, a quick glance revealed this shocking image (of the sprocket/retainer/shaft, not my manliness!)
  
  
  
  See above comment
  
  
  
  Sprocket looks fine, but does wobble a little on the shaft
  
  
  
  See above comment
  
  
  
  Sprocket cover after removing the worn central section
  
  Any input is very gratefully received! Thanks in advance! If we meet, payment in beers. If not, good Karma all round!
  
  Ride safely,
  
  Chris
• varakurt am 25.8.2012
  I would prefer solution Nr.: 3.
  If this solution doesn't work you have the posibility to weld the sprocketanother time somewhere in Mongolia/Siberia. I think it isn't so difficult to find a guy who can do that ...
• Stefan_Kremer am 25.8.2012
  Chris,
  
  Chain tension IMHO is for offroad use a bit to tight
  get a new sprocket (complete chain-kit of course would be the best) and new retainer and make sure that the sprocket is mounted the right way (inside/outside)
  
  Welding is the last I would do, as any further sprocket replacement means a lot of hustle.
  
  best regards + good luck
  Stefan
• chris am 25.8.2012
  Sorry to not yet have responded to all the people who have replied: I need to go out for food. Mongolia is 7 or 8 hours ahead of Europe. I will tomorrow.
  
  Possibly I put the rear spacers on the axle on the wrong way round on the last tyre change. Hence the sprockets are out of allignment.
  
  Can somebody with a rear disk model pd06 Transalp (or even Africa Twin) nip out to their bike and tell me which side which spacer is? On my bike it's currently the bigger one on the left (sprocket) side and the smaller one on the right (brake disk) side.
  
  I will do all the checks suggested tomorrow in the daylight. There's a dutch Toyota Landcruiser man here too who has a full workshop with him. I'll be raiding his stuff
  
  Many thanks!
• varakurt am 25.8.2012

  "chris" schrieb:On my bike it's currently the bigger one on the left (sprocket) side and the smaller one on the right (brake disk) side.

  
  
  This are the right positions.
• Michael1972 am 25.8.2012
  My mention is, chain tension is too strong but this is not the problem, maybe the sproket isnt in correct orientation or its mechanically wrong, or maybe the rear wheel isnt in the right position left and right distance rolls are not correct so the wheel is not in the middle and the chain is moved to the left side and pulls the sproket to the left. Use greese for the output shaft.
• chris am 26.8.2012
  Sorry for taking so long to get back to you all. Been busy working on the bike and dodging sand storms. Now it's raining!
  
  
  
  Hope you don't mind me admitting that I posted my original help request on 4 different forums. The level of help and really useful advice has been outstanding. It's great to know that so many people care about your wellbeing. Please take this reply as aiming at all of you. Sorry, with is super slow internet connection, I'm unable to reply to you individually.
  
  
  The posts are at
  
  
  http://www.horizonsunlimited.com/hubb/honda-tech/advice-needed-mongolia-transalp-output-65929#post390382
  
  http://www.xrv.org.uk/forums/transalp/82359-advice-needed-mongolia-transalp-output-shaft-sprocket-retainer-problem-urgent.html#post643588
  
  http://advrider.com/forums/showthread.php?p=19441010#post19441010
  
  http://www.transalp.de/forum/beitraege/technik/advice_needed_in_mongolia_transalp_output_shaft_sprocket_retainer_problem_urgent/#pid
  
  
  So I did the following today.
  
  
  Removed bashplate and checked chassis for damage: None found.
  
  
  Checked engine mounts: All tight
  
  
  Checked swingarm for damage: None found.
  
  
  Rechecked swingarm bearings: Fine
  
  
  Checked rear wheel bearings: Seemed fine.
  
  
  Checked sprocket carrierbearing: Some play
  
  
  Checked chain tension again: Still too tight, so loosened after doing all the work on the bike
  
  
  Removed front sprocket and checked output shaft: no movement l/r, up/down, nor in/out.
  
  
  The front sprocket is definitely on the correct way round. It may or may not be an OEM part, the discussion from May this year about it is at http://www.xrv.org.uk/forums/transalp/80894-t-front-sprocket-question-similar-question-but-different-others.html There is no writing on it.
  
  
  The sprockets inside and out are pictured below. There is clear wear on the outside front and inside rear. Hence chain out of alignment, as suggested by most people. So if the front sprocket is cool, the problem is with the rear?!...
  
  
  
  Rear outside
  
  
  Rear Inside
  
  
  Front outside
  
  
  Front inside
  
  
  
  As was also suggested, I put the bike vertically on a stand with the back off the ground, removed retainer, put front sprocket in correct position, started motor and engaged 1st gear: The front sprocket immediately skipped outwards to the end of the shaft, then continued to move left/right way beyond where it should sit.
  
  
  So removed back wheel. The cushdrive rubbers looked a bit dubious (They will also be replaced next summer before setting off for Siberia)
  
  
  
  
  Replaced carrier bearing and also the other 2 rear wheel bearings (I knew there was a good reason to carry all these heavy spares...). I say replaced, It was Roy the nice Dutch chap in the Landcruiser who did all the work. He's a heavy plant mechanic, so a fat Honda was quite familiar to him:
  
  
  
  After cleaning everything, smoothing out the burrs in the central bearing spacer tube and greasing stuff we put everything back together. The 2 outer spacers were in the same position as previously. Longer one on the left/sprocket side, shorter one on the right/brake disk side. Everything seemed to fit much better.
  
  
  Finally, ran the bike in 1st again, with a looser chain too and the front sprocket stayed where it should! While I was twisting the throttle somebody else standing 3 meter back behind the bike thought the chain was running true too.
  
  
  I put on my final new retainer (number 4) and will take the bike for a spin out the the giant Chinggis statue tomorrow. Wish me luck! I'm very hopeful things will go well.
  
  If all does work out well then the problem was caused by a slightly loose carrier bearing, a tight chain and possbly sh!te cushdrive rubbers. On the last tyre change in the stoney/dusty/dirty carpark in front of the Russian tyre-wallah's shop I may have been less than subtle too. If not...?
  
  Next summer I'll also bring a complete new C and S set, plus new spare retainers and also a couple of modified retainers as described by East Coast in post number 6 at http://www.xrv.org.uk/forums/transalp/82359-advice-needed-mongolia-transalp-output-shaft-sprocket-retainer-problem-urgent.html#post643588 Conveniently I have a 1987 TA at home too, so have a demo model to test it on. Or EC will sell me one of his
  
  
  I'll advise how I get on following the test ride.
  
  
  Cheers!
• chris am 27.8.2012
  The test is done and the evidence is below. Only 100km/60miles virtually all on pavement, but I did regularly try to simulate riding offroad/sand by riding like a tosser, er I mean, a Mongolia car-jockey/trucker.
  
  
  thickness
  
  
  Inside
  
  
  Outside
  
  There's v little wear on the retainer that started the morning as a new part. One of the 6 splines on the retainer is even spotless! I believe all Transalp retainers will inevitably have some surface damage just because of the (stupid?) design of the shaft. As my current front sprocket wobbles (do they all do this from new? As mentioned in a previous mail the ones on a BMWf650 don't/shouldn't), probably because of the tight chain/shagged carrierbearing/cushdrive pulling it the wrong way.
  
  I'm going to do the trip to Siberia as planned next summer and take the parts with me as mentioned.
  
  So, 2 things I've learnt when riding Honda v-twin dualsport bikes when doing a lot of offroad/sand/mud: Run your chain real loose. Also (all the time) when checking rear wheel bearings, don't just wiggle the back wheel in the swing arm, but also wiggle the sprocket carrier separately too.
  
  All the best to all and hope to see you near a bar somewhere
  
  C