Yamaha forks on a BMW F650GS Dakar

Discussion in 'Thumpers' started by skibum_1260, Oct 23, 2008.

  1. Kainic

    Kainic Almost there

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    House of Horsepower is supposedly working on solution.
  2. Dan Alexander

    Dan Alexander only happy when sad

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    I had a Scotts on my Super Enduro and it was good and used ones seem to come up for sale fairly often.
  3. Dan Alexander

    Dan Alexander only happy when sad

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    I've gone to their website before but there wasn't really much info it seemed.
  4. nomad5326

    nomad5326 Xventurous

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    Contact /email Highway DIrt Bikes. They will make one. Just send in your ignition pod so they can cut it. Have them make it two piece (ignition and topclamp). He said no problem and you can mount dampers, etc.
  5. nomad5326

    nomad5326 Xventurous

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    Bobby, you may have missed it. To kep original OEM geometry 1" is all you need to go unless you keep the YAM height and respring/raise your rear 1" (lowering link will do this). Most of us left full YAM height and resprung the rear to get full suspension travel. I still use my OEM Dakar fender and just upped the fluids to 10W and re-sprung my Wilbers for my height/weight.
  6. WayneC

    WayneC Long timer

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    Barnman, thanks for the measurement, appreciated, that ABS/Flasher switch mount looks neat on your set up

    The spring rate of 6.0 quoted by the suspension guy from the post above suggests he is not thinking of the differences between damper rod forks and cartridge forks, It would be a harsh old ride at that spring rate. A spring rate comparison chart is here http://www.f650gs.crossroadz.com.au/Modifications/Forks/WeightVspringKG.pdf
  7. Schlug

    Schlug JockeyfullofBourbon

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    put something on and stay in that position.

    Missed it? I read for hours trying find actual numbers for length and couldn't find much but a lot of anecdotal talk about what seemed to work and not work.

    The springs have been ordered and a new Ohlins shock with proper spring rate and valving for weight. I haven't made any adjustments in rear spring height to account for height of the new forks, just proper sag.

    If 2" is short I'll have it brought to 1". Not the end of the world. But you can believe I'll have it all together this way and let you know the results. of a Ohlins shock sprung properly and forks shortened 2" sprung properly. If the bike feels divey or twitchy or the geometry is all wonky I'll put the fork back up an inch. My suspension shop is more than willing to tinker about and so am I.
  8. Kainic

    Kainic Almost there

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    Send them an email or give them a call.
  9. nomad5326

    nomad5326 Xventurous

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    I'd read this first.
    Not many have had dampers on their bikes (but some have). Bike IMO just doesn't need it OEM or KYB front end if all is right in the front end world.
  10. Lupin 3rd

    Lupin 3rd Raygun Gothic

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    I've been thinking about this swap for a while, I recently found a pair of '01 YZ 250 R forks and axle for a nice price on eBay and decided to start the gathering.

    I get a lot of use out of the GS as my commuter and I'd really like to keep the ABS so I'm looking into options to use the stock wheels: except for Hawk engineering what other options are there? I think I did my homework and from what I've found in this thread it seems like people either get the kit or dump the ABS and use a 21" YZ or WR wheel. Just to clarify, I'm not here to put down the work by the guys at Hawk, but I like to experiment and try doing things differently.

    Right now my main issue is the bearings: the GS has a 17mm axle and 17x40x12 (6203-2RS) bearings. The YZ has a 20mm axle, and the closest fit I've found to that is 20x42x12 (6004-2RS). Can the GS' wheel hubs be bored out from 40mm to 42mm to accept the larger bearings? Would this be a safety concern (not enough material on the hub leading to cracking)? I looked for 20x40x?? bearings, but they seem to be more rare than hen's teeth...

    I found the front caliper and bracket from a WR250X and the disk rotor has the same diameter as the GS so that would be a perfect fit if I could get the wheel on...

    Thanks in advance if anyone can help.
  11. WayneC

    WayneC Long timer

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    There is not enough in the GS hub to take the bigger bearings, the G650X has a hub with 20mm axle, if you looked around and picked up a 650X hub many things may fall into place

    Interested in more information re the WR250X disc size, did not know any used a 300mm rotor, they would be a potential source of caliper brackets
  12. Lupin 3rd

    Lupin 3rd Raygun Gothic

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    The X is the sumo version of the WR250R: 17" wheels and a 298mm front rotor with a different bracket and caliper. The bracket mounts to the standard WR/YZ forks so there's nothing special there. Sourcing the bracket and caliper from an X can be a problem since they're not very common, only found one on eBay so far. However there's plenty of 320mm bracket & rotor kits from China, don't know about the quality, but it's an option.

    I've looked for G650X and F800GS wheels, but haven't found any for a reasonable price (for me less than the cost of the Hawk Kit). One of those would completely solve my problems!
  13. DrLuke

    DrLuke Adventurer

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    Wayne,

    What do you reckon a 2002 F650GS (26000km) with the Yamaha forks mod and every farkle imaginable is worth? (21",18" Excel rims, all bash guards, staintune exhaust, EFI controller, air intake, ABS setup and connected with BMW discs, new centre stand and sidestand, new rear shock and resprung front end, touratech panniers, changed gear ratio, new chain etc etc) Not sure if I want to flog mine or not there was a lot of love put into building the bike, however, I may need the money. more than 5? poss 7 or an I dreaming.

    Cheers,
    Luke
  14. WayneC

    WayneC Long timer

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    DrLuke, afraid I have not looked at used values for the GS as I have had no interest in buying or selling

    Yours does sound rather neat with the mods, I suspect in a general market you would not get a good return on the investment in all the gear but to someone wanting to buy and the set one up then it could command a good price and so perhaps 5 to 7 may be possible. Overall though you would probably get a better return by parting out the panniers and other bolt on items

    My thought is I hope you dont get to the point of having to sell it, bird in the hand and all that, especially after all the effort
  15. Aquatic

    Aquatic Long timer

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    I paid more for less on an older bike with more kms. If I was still looking I would have paid 7
  16. WayneC

    WayneC Long timer

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  17. Aquatic

    Aquatic Long timer

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    That one is on the Aussie fleamarket as well - http://advrider.com/forums/showpost.php?p=20551102&postcount=139
  18. GSBS

    GSBS FunHog

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    ...before spending $6-7K on a used Dakar I'd give this a serious look.

    Husky 650 Terra with 650 Rotax single engine, with claimed 58 HP thanks to cam, other modifications, 18/21 wheels, Sachs suspension, including USD forks. MSRP $7K new. Aftermarket farkle machine is gearing up already.

    [​IMG]

    [​IMG]
  19. Gravel Seeker

    Gravel Seeker Thomas

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    It's NOK102.900 here (USD18.600) :cry
    Sweet looking valve cover on those....wonder if it's a straight swap for ours...
  20. Aquatic

    Aquatic Long timer

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    With the help of WayneC1 I am coming up with a Ignition mount for the YZ conversion.

    I have the Dakar top clamp roughly modelled up
    I have Wayne's Ignition mount for a TT/WP top clamp modelled up

    Next is the YZ top clamp which will have to be a little more precise.

    I also want to make up a totally new hybrid top clamp that will be a straight fit for a YZ lower Clamp and a Dakar frame. As well as a top and bottom clamp with spindle set.

    I also would like to add an optional damper mount. Any advice on what would be the best(read most common) mounting hole pattern to use?

    Have a look here

    https://www.dropbox.com/sh/vf42u44z73izub9/TWvmmbZ0u_
    (click on a file an then download top right)

    Please, any suggestions would be good.

    Also in the folder is the "in progress" 3D model of my 2001 Dakar. Wudyafink?