F800GS 15 Tooth CS Impressions & Questions

Discussion in 'Parallel Universe' started by Desert Dave, Apr 24, 2009.

  1. Full Power

    Full Power Long timer

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    I have a 17 tooth c/s sprocket on order for the F800.
    I expect to lower my top gear RPM by several hundred.
    The bike spends FAR more time in 6th gear than it does in First.
  2. MCMXCIVRS

    MCMXCIVRS Long timer

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    You could replace the washer if it gives you peace of mind, but not really necessary to do so. No reason to even consider changing the seal unless it's leaking.
  3. Calgary06

    Calgary06 Been here awhile

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    Thanks guys,
    I am going to replace the spring anyway as it is only a few dollars.
    Hardest part was finding for rear hardware (bolts and nuts) at a reasonable price. My dealership wanted over $60 for a set of 6... They must have been individually hand delivered to the parts desk in rental ferrari's or something.
    P
  4. Geoffster

    Geoffster Fool - Born This Way

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    BMW wants you to be prepared to shoot down Sopwith Camels or Spitfires with your F if necessary.

    (Like these are really one-time only items? Perhaps in the sky ...)

    Be sure to use blue Loctite on the countershaft bolt. IMHO, that's more important than a new diaphragm washer. My G650X used the same system, and the ONE time I didn't apply fresh Loctite, the bolt began to back out.
  5. JRWooden

    JRWooden Long timer

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    I have the rev. #4 BMW manual and for the rear sprocket it says the nuts are single-use but does not mention any warnings on the bolts ... on my bike it looks like the nuts are intentionally mechanically deformed ...
  6. Calgary06

    Calgary06 Been here awhile

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    I'll have a look at them when I pick em up next week. I guess I may have spare bolts once I'm through but that will be OK.
  7. Snowy

    Snowy Long timer

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    I've now tried a 17, 16 and 15 on the F800. For off road and 2 up mountain road carving the 15 is great. For a combination of all things the 16 works fine and the 17 is great if you need to do a quick weekend 3000km round trip.

    I dropped the gearing on one of my DRs for a trip up Cape York a couple of weeks back, and instantly regretted it as I spent about 95% of my time at freeway speeds on the dirt. Next trip, I'll take the smaller sprocket in the tool bag, and change it the night before the tricky sections of the trip. It's all of a 10 min job, if that. Same goes for the BMW. When faced with a few thousand kms of touring speed to get to the "good stuff", I think packing the spare sprocket is the smartest option.
  8. JRWooden

    JRWooden Long timer

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    Swapping them is my plan for the next trip ...
    Question:
    What do you carry with you to apply the required 100Nm of torque to the rear axle nut (and where do you stow it)? :evil

    Thanks!
  9. Bayner

    Bayner Long timer

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    I have a Fredette Racing axle wrench (pretty short); it would suffice but required work hardened hands to accomplish it. I've since used a motion pro tire spoon/wrench combo thing and it's easier given it's increased length and girth.
    Still have to yard on it pretty firmly though.


    But neither of those will help you install at 15 or 17 tooth C/S sprocket :lol3


    (http://www.youtube.com/watch?v=9hT-t19CJ4E)
  10. Snowy

    Snowy Long timer

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    What....the.....fu....oh, you're just messin with my head.

    I know, it's so over thought. I figured the so called "Last Great Adventure" based on my memory of it from 20 years ago, would require a modicum of preparation and off roading skill. Turns out my moving average over the 2500kms of mostly average dirt was 98.7km/h.

    If I'd taken a bigger sprocket it would have gone back on the first night.

    But, at the same time, there are stories emerging of people we passed and met who trashed bikes and broke bones at far lower speeds.

    Preparation is the key. Over prepare and you'll probably come away saying "Well...that was easier than I remember it".


    and no...the c/s shaft bolt isn't an issue. Hasn't been once yet. I use the same toolkit off road as I do when I change sprockets. Why some people have issues with these things is beyond me. Unless I watch my 3D games programmer son trying to work on his ZX6...then it makes perfect sense. Oh my....humanity is doomed...
  11. JRWooden

    JRWooden Long timer

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    Thanks guys! :lol3

    I know I over-think things but every once in a while I surprise the crap out of someone with a clever bit from my tool bag which makes it all worth while... Like when a buddy dropped a nut in the leaves during repairs from a dirt-nap and started cussing a blue-streak as it was a critical fastener ... the little high-strength magnet I have in my bag found it in no time ....

    I try to work only from my bike kit when doing maint/repairs so as to discover what is not in the bag that perhaps should be added (or could be jettisoned ...) I have the F658GS so carry a plugger & compressor but no tire spoons.

    I have a 24mm socket for the axle nut, a ratchet head that accepts extensions as it's handle ... with both my 3" and 6" extensions installed and a well-placed booted foot I've removed and reinstalled the nut in a pinch once, but was fishing for better ideas.
  12. Calgary06

    Calgary06 Been here awhile

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  13. JRWooden

    JRWooden Long timer

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    Thanks for that tip ....
    I think I'll go out and spray some penetrating oil on mine now :wink:
  14. XT Traveler

    XT Traveler Been here awhile

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    I have a 13' F800GS and agree that first gear is too tall for an Adventure bike that will actually get used off road in more technical stuff. A 15 countershaft sprocket of course helps as does a Rekluse clutch but what is appalling to me is that not only did BMW not bother to put the right gearing in the bike from the start they have persisted in ingnoring all the complaints from F800GS owners (their customers !!!) for years now -- they are putting manufacturing convenience and cost well ahead of basic design criteria and consumer satisfaction. Very poor IMHO and :topes that we have to put up with it. BMW -- just put a lower first gear in this bike !!!!!!


    ...
  15. Geoffster

    Geoffster Fool - Born This Way

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    A soul at a BMW dealership told me the company is chasing exceptional gas milage and EPA standards. When one lives in an environment in which unelected, unaccountable bureaucrats and irrational regulations can make or break a company, one does what one has to do.

    I suspect that just as The Motor Company anticipates exhaust system modifications, BMW expects consumers to pick their own final drive ratio on its chain drive models.
  16. sorebutt

    sorebutt Long timer

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    A lower 1st gear won't change mileage because test aren't done in 1st gear. It takes less gas to start out in a lower first gear. I think they design the bikes for going to Starbucks. However, the stock 1st gear is too high for getting around the parking lot.
  17. JRWooden

    JRWooden Long timer

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    There was a comment sometime back regarding meeting noise limits and that the taller first gear was required to meet that requirement...
    It could be just a story ... i don't know...........
  18. sorebutt

    sorebutt Long timer

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    Then why were they able to lower the first gear on the 2014 model if noise was a problem. It sound like a BS excuse to me.
  19. Geoffster

    Geoffster Fool - Born This Way

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    Since all well-intentioned suggestions make you argue, figure it out yourself.
  20. Snowy

    Snowy Long timer

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    The answer is simple.

    You're all wrong.

    It was a street bike engine intended for use in a multi platform model line up, and was adapted to fit into the trellis frame designed for the GS model variant.

    It was tilted rearward to allow for larger diameter front wheel and longer travel suspension.

    The drive was changed to chain.

    It was never "designed" to be an engine in a "off road" bike. It was designed to be a multi platform engine.

    BMW was aiming, according to their early marketing literature, at creating an entry level bike for the "Adventure bike market". The aim, according to the local sales guys at least, is to win over more of the Jap bike crowd, and then gradually convince them they need an R1200GSA.

    Now they tell me that BMW has recognised that they're losing sales to the Japs because the big GS range is too big and too dirt oriented, not fast enough, not sexy enough....so....they now have the S1000XR to offer. Basically a sports tourer with 160 angry ponies. Because....angry ponies....sexy...fucken....

    In short, it's all about marketing, using one engine across multiple platforms, and saving costs. Developing multiple variants for each engine platform (hence the S1000XR). Sell as many as you can with as little retooling as you can.

    To change the ratio BMW was at least trying to respond to some of the criticism aimed at the F/GS range. They wont fit better suspension because suspension is one of those "emotive" topics where every rider has a preference. So they leave that for the individual to figure out. It would have been easier if they used a fork that was common to at least one other popular bike, so that there were off the shelf solutions already in place......but I digress...