HPN - I just want one

Discussion in 'Airheads' started by Dakar83, May 4, 2012.

  1. Dakar83

    Dakar83 Been here awhile

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    Went for a ride on the R80G/S today, been wanting to give it a good run to blow out the cobwebs. Weather this morning was a blue skies and 27 degrees celsius, just perfect for riding, made better by no weekend traffic !

    Headed up to Toodyay on the bitumen, just taking it easy and enjoying the quiet road. There were about a dozen bikes in town, all the riders grinning at their good fortune getting away for a Friday morning ride and catching this great weather in between the Heat waves!

    On the way back I couldn't resist taking the old scenic road north of Toodyay.

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    The bitumen quickly gives way to a nice gravel road through some hilly pasture and farmland before moving into native forest.
    The road follows the rail line much of the way

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    I have not taken this bike on loose gravel before so went slowly. I was rewarded with a surefooted ride the G/S behaved impeccably until some corrugations had me thinking the suspension might be set a bit hard (the bouncing unlocked the seat! but no drama, just pulled over and locked it back in).

    Too soon it was back onto the bitumen and head for home back in time for lunch. Though I did see a number of side roads that really are asking to be explored. I think I'll have to borrow my son's GoPro and head back up there on the HPM. ;-)

    Now for some forum participation!
    The G/S has been throwing some oil on the rear wheel, at one point I thought it was just from the top filler plug. but now I am thinking it may be more ominous. Only the right/drive side of the wheel gets the spray, as you can now see thanks to the dust from this mornings ride.

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    There was no oil residue around or under the filler plug, checked the drain plug which had a new crush washer at last service. Looks to me like thats where it's coming from and I was able to nip it up another 1/8 of turn, so I hope that'l sort it. Any other views?
  2. Rucksta

    Rucksta SS Blowhard

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    Replace the "O" rings on the shaft that actuates the rear brake.
  3. hardwaregrrl

    hardwaregrrl Can't shoot straight Supporter

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    +1. Make sure they're genuine BMW parts.
  4. rediRrakaD

    rediRrakaD Whoopdie do Supporter

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    Or have a friend machine a second groove and add another 'o' ring :evil.
    S.
  5. Ras Thurlo

    Ras Thurlo Desert Lion

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    btw- great numberplate


  6. Dakar83

    Dakar83 Been here awhile

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    Thanks for the advice about the o-rings on the rear drum pivot arm. I didn't realize this tracked through the final drive oil reservoir.
    When I removed the pivot arm about 15-20mls of final drive oil leaked out of the pivot arm hole, is that normal? Bike was level.

    The next surprise was the absence of a washer from the inside end of the pivot arm. This washer appears in the BMW schematic and the Clymer manual. However it appears as though this unit is designed without the washer as the surfaces are a good flush fit and the splines on the outside end of the pivot arm would not fully protrude if a washer was added ?? The bike is Oct 1980 build date.

    Anyway I was able to pickup some o-rings from my local BMW dealer 32c each, can't complain!

    There are several grooves in the pivot arm but only 3 are machined with a square profile (good information from Snowbums blog)
    2 are on the inside end which did not appear to leak, one on the outside end which seems to be the culprit. I have only changed the outer o-ring. Now I'm thinking I should have done all 3!

    Anyway here are some pictures
    First the inside of the final drive. Dry except for slight signs of oil around the bolt above the pivot arm? It was tight.

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    Here is the washer-less pivot arm with 3 o-rings


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    Now I'll just have to get out for another good run to see if the problem has been resolved.

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  7. Dakar83

    Dakar83 Been here awhile

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    Thanks Ras
  8. Rucksta

    Rucksta SS Blowhard

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    Your's look like it has the usual mod for the age with at addition of an extra groove on the brake side.
    It seems only the "O" ring closest to the brake shoe wears significantly.
    I change all three so I can do a swap around in the field if it starts leaking on a trip.

    Later models - post '83- have a brass tube running through the FD and were fitted with four "O" rings.

    My '82 came with a washer and a felt pad on the brake side and a wear indicator on the lever side - both long since gone.

    The leakage around the bolt is typical of a broken gasket.
    Std assembly uses a paper gasket; common practice is to use a sealant instead of a gasket.
    The variation in thickness of the gasket must be accounted for in the stack of big shims that determines preload on the big bearing.

    You may be able to open the housing throw some some sealing goo on the surface and reseal without having to reshim.
    Alternately removing the bolt and sealing with silastic may get you through to the next FD service or you may learn to live with the leakage

    The hole above the bolt is an inbuilt puller for the inner housing - look for a matching hole at 180 deg.
    Moderate heat - propane torch - will ease the disassembly process.

    350ml is the specified oil volume.
  9. One Less Harley

    One Less Harley OH.THAT'S GONNA HURT

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    mine leaked at the brake pivot, you might make sure it's not loose as mine was. I pulled it out and put permatex #2 on the pin. It's been dry every since.
  10. Dakar83

    Dakar83 Been here awhile

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    Thanks Ruksta that's really usefull information and it gives me a progressive plan of action.
  11. Dakar83

    Dakar83 Been here awhile

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    Thanks for the suggestion, I think I will try the o-rings first and look into the missing washer and felt.
    If that doesn't work then it might be time for the permatex
  12. Andy_unaventurous

    Andy_unaventurous Lost but not fearful

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    Hello everyone,
    I'm not a frequent poster but I think I can feel it coming on. Right now I have just read this thread grinning from ear to ear. Its a great deal to take in at once, but here's the thing, ages ago I bought a R80GS off an old bloke who had not maintained it at all well, although mercifully it was ( and remains ) dead stock.
    Over the last couple of years I've done a little to it, removed the colony of spiders inside the headlamp assembly for one!
    I lost my marbles a month or so ago and shipped it to a bloke in Tassie, but he had some issues and the deal didn't go through, and I reckon I dodged a bullet.
    Im getting the bike shipped back and I'm not going to do that again! Silly me!
    I'd like to upgrade the starter to the nippon denso unit for a start (recently she had new rings, cam chain, bits and pieces , but I know the starter is cranky ( so did the guy who was going to buy it!) so could someone please post info ie part number and where to get one for that nipondenso starter.
    Im dreamin R80GS again

    Andy
  13. chasbmw

    chasbmw Long timer

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    In the UK the ND starter is available from Motorworks, I don't know if they ship to Aussi or what the costs are but worth an email.

    The starters are manufactured by Emerald Isle in Taiwan, but I don't think that they sell direct unless they don't have an aussi dealer.

    Before replacing the starter it's worth checking that the engine is running well and that there are no carb related issues,
  14. Andy_unaventurous

    Andy_unaventurous Lost but not fearful

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    Thanks Charles.
  15. Dakar83

    Dakar83 Been here awhile

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  16. Andy_unaventurous

    Andy_unaventurous Lost but not fearful

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  17. Dakar83

    Dakar83 Been here awhile

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    I have fitted new O rings and washer to the rear brake pivot arm but I haven't had the R80 out for a good run yet. However I did get to take the HPM out on Friday. The plan was to explore some roads through the Moondyne / Avon Valley National Park area. Essentially to find some easy GS dirt roads and may be a campsite for a future club run. I was joined by Noel on his R1200GS, I always prefer to have company riding off road, you never know when you may need a hand and anyway it tends to make you feel comfortable to explore that bit further.

    We soon got onto the dirt near Chittering,the hot weather of late meant the gravel was dry and quite slippery. A few km into the bush a crazy Emu tried to head me off. I saw it out the corner of my eye running through the Forrest to my left on a perfect collision course. I sped up a little to get ahead and hoped Noel was far enough back to avoid trouble. Thankfully he was and told me at the next corner stop that it shot onto the road behind me turned slid, fell on its ass then took off in the opposite direction just before he reached it. It's good to know that even the Emu's find this gravel a bit slippery, makes me feel a bit better ;-)

    Another 5 minutes later we came upon a family of Emu's walking along the road, mum and 5 chicks about a foot and a half tall. They took off running straight down the road. I slowed down and followed for a little way hoping they would turn off the road. I was just thinking I would need to stop and wait for them to get off the road when I heard Noel's GS accelerating hard. He flew past me and straight through the middle of the group. Emu's scattering everywhere 2 off to the left one right and 2 chicks madly flogging straight down the road. I didn't want to separate the 2 from their family so decided to follow Noel and shot through. (no Emu's harmed :-)
    I had my son's Go Pro on the crash bar and later found I had some neat footage of this encounter and some later moments) sadly I managed to delete the files the next day before copying them to my PC.

    We came to a turn off to what appeared to be some campsites, aptly named Emu Falls
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    from here the ride departed from easy GS roads and got quite challenging but real fun.
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    We were heading down into the Avon River Valley and the road became track which became progressively more eroded. We came to a point above the river were the track became a steep descent of 1.2km down to the river. Deep washouts cut their way down the track which was baked hard but covered In a fine layer of loose sand and scattered with rocks. Oh well Noel was heading down so I was following. 40m in my front wheel slipped into a rut almost deep enough to catch the pots in trying to escape it I scored the bikes first battle scar a paint rash down the left Cylinder crash bar (really pleased I fitted the HB crash bars they totally saved the rocker cover.

    It was a hairy descent a few pucker moments but no off :-) though I did stop to walk a corner and check out the track. So Noel made it down a few minutes ahead of me. On reaching the bottom there was a really neat camping area and of course the Avon river running quite quickly across a pretty descent causeway under almost a foot of water. Noel was chatting to 2 ladies on the edge of the causeway, their young kids splashing around near the bank. They explained that they had accessed the river from the opposite side and parked their car about 2km up the road,the access having been blocked to stop traffic. We decided to cross the causeways and head up the hill to try and find a way across the railway line and onto the next site we wanted to find. the causeway crossing was fun alas more great footage lost :-( we had to bush bash some logs and ditches and weave through the Forrest to get out onto the gravel road. This lead up to the first of 3 boom gate barriers. We followed the railway line looking for somewhere to cross. It was beautiful country and great riding but finding a crossing was proving hard until Noel spotted a storm drain/pipe running under the rail way embankment. It was just big enough to ride through, on the other side another bush bash up the hill and we were onto a park road heading towards Toodyay.

    After a great run through some hilly forest we reached the turn off to Cobbler Pool and headed down for a look
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    It looked like a nice spot for a camp
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    From there it was a nice run into Toodyay for a late lunch and refreshment break. An hour later and we set off via some more dirt and then a nice run of bitumen twisty's through a beautiful hilly area that was super quiet (only passed 1 bike and 1 car over 30ish km) a chance to lean the bike into the turns and check out its corner handling. The grin on my face and the short wait for Noel at the end of the section was evidence enough that the HPM handled it really well. On getting home I was proud to see that the knobbies were showing wear right up to the edges :-)

    All told a great day out and a ride I'd be happy to take again. 282km 4.5 hours saddle time. The HPM was quicker and more comfortable than the DR and just as capable off road. Seems pretty economical too, though I haven't worked out the consumption yet. Just a pity I deleted the GoPro footage, oh well a good excuse to go again!

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  18. bully1

    bully1 Long timer

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    gotta watch the track along side the railway line up there Jono, one of the blokes that I ride with is pretty high up with the railways, tried to get the keys for the gates. Was told a definate NO and was informed that there are camera's along the track in places. They really don't want people in there, I've done a bit of it, came in from Bells rapids.
  19. Dakar83

    Dakar83 Been here awhile

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    Oops, thanks Bully, will keep that in mind.
  20. gary5410

    gary5410 Been here awhile

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    Who is SWT? I can't find them! :huh

    Gary