21" front on R1200GS LC

Discussion in 'GS Boxers' started by Camel ADV, Feb 10, 2015.

  1. Camel ADV

    Camel ADV Long timer Supporter

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    My friend Pat's 2014 R1200GS LC was in need of a new front rim as the stock 19" was trashed. He was hoping to replace with a 21". He's up north working in the oil fields and didn't have time to deal with it but has plans on racing this bike in the ADV class at the Desert 100 race in April. I've got time and space so I offered to tackle it.

    I looked around trying to find someone who had done a 21" front on an LC but couldn't find one anywhere. I called Woody's Wheel Works and asked them. They said they had lots of inquiries but hadn't made one as there wasn't enough room between the front fender and tire.

    I mocked up with a rim off a YZ dirt bike just to get an idea of what needed to be done. The guys from Woody's were right, only 1/8" clearance between the top of the tire and underside of the low fender. I peeled the fender off, gained about 1/4" but the brake line "T" hung down another 5/16" so we were going to have to get new brake lines made.

    The stock rim:
    [​IMG]

    [​IMG]

    YZ450F rim, as you can see very tight to the fender.
    [​IMG]

    [​IMG]

    The offending brake hose "T":
    [​IMG]

    The new Excel 21"x1.85" Super Laced rim from Woody's Wheel Works, work of art as always:
    [​IMG]

    [​IMG]

    Not much clearance. Didn't help that I opted to go with a 80/100-21 instead of the 90/90-21. I wanted a little more cushion:
    [​IMG]

    Pull the brake lines= 5/8", all good:
    [​IMG]

    One of the other issues is the spoke/caliper clearance. The stock R1200 rims are "X" laced normally there's lots of room for calipers. Going with a 21" rim meant the spokes terminate in the middle of the rim rather than the opposite outside bead. I wasn't sure things would clear, Woody's said I may have to file a little bit on the caliper. I was pretty happy when I bolted everything up and saw it all cleared with about an 1/8" to spare. Tough to see in the pic:
    [​IMG]

    Pat is a seasoned dirt bike racer having been a factory rider for Yamaha and International Six Days Enduro competitor in his younger days. This bike will get the wheels ridden off it, no RTW trips here. On top of the Desert 100 ADV Class race in April, Pat plans on adding a road book and ICO so he can compete in the Baja Rally 3.0 in Sept. Given the plans for the bike weight reduction is important. We have been on the same page with most of this project but we disagree on the single or dual caliper/rotor. Pat wants to run a single rotor/caliper on the front and that would normally be something I'd agree with (stripped down to one on my F800gs). My concern is that this bike has linked brakes so the right hand lever activates all three calipers. Removing one 4 piston caliper from the equation may mess up the front-rear braking balance. Normally when you drop a caliper you run a master cylinder with a smaller diameter bore so it pushes less fluid. If you don't, you get a very stiff lever and weak braking. Since it's Pat's bike, it's up to him so one caliper/rotor it is!

    Since the stock brake line had to go because of the "T" fitting clearance issue, new line(s) was needed. Unfortunately to get to the hose fitting on the ABS unit you need to remove the airbox. To get the air box out you need to take the gas tank out. To get the gas tank out you need to strip the plastic...
    [​IMG]

    ABS unit, front brake line is the upper right hose with no banjo bolt in the pic:
    [​IMG]

    Keeping in mind that we may have to re-install the 2nd caliper, I didn't want to order a new brake line so I used a universal DOT hose with treaded ends to banjo fittings. Once Pat decides if he's staying one caliper or not, a new crimped line can be ordered.

    Again, once Pat decides on the brakes a new bracket can be fabbed to retain the hose and ABS line. In the meantime a cable tie will suffice (will get a beefier one though):
    [​IMG]
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    Looks pretty good I think. The 21" added enough height that the center stand is basically useless as both tires are still on the ground:
    [​IMG]
    [​IMG]

    Now, what to do for a new fender...
    #1
  2. pistole

    pistole Long timer

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    holy mama !

    great work and keep us posted.

    .
    #2
  3. RJK

    RJK Been here awhile

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    This will definitely be a thread to follow.

    On the bright side, since the centerstand is to short now, taking it off will shed some more weight :D
    #3
  4. Skyliner33

    Skyliner33 Been here awhile

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    How much difference to the handling of the bike will the 21"front make. As the rake and trail must be quite a lot different than standard.

    Can the yoke be dropped down the forks on these bikes? Ive only messed with standard forks before.


    Edit: Ignore the comment. It would make things worse on thinking about it.
    #4
  5. RJK

    RJK Been here awhile

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    #5
  6. BriKielyGSman

    BriKielyGSman BigBadBri

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    Mine next please. :-)
    #6
  7. GSMarc

    GSMarc Long timer

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    the HP2E had no other front fender.
    #7
  8. RomaDakota

    RomaDakota Experts agree!! Supporter

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    It also did not have two radiators within rock shot.
    #8
  9. Camel ADV

    Camel ADV Long timer Supporter

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    For some reason Pat wants to keep the center stand. I'll have to find a GSA version or splice some tube in to lengthen this one.

    The rake and trail will have definitely changed. I feel the stock geometry causes quick steering so a bit more rake will help. Will this be too much, not sure yet.

    I emailed them and they said it wouldn't work with the LC bikes unfortunately.

    The rads are an issue also the area around the gauge cluster near the triples is wide open. On a wet day all the spray off the tire would come straight up and on to the rider.
    #9
  10. Disco Dean

    Disco Dean Long timer

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    I have a 21 on my bike and handling differences are negligible to turn in. Keep in mind this is not the same as lowering or raising the forks in the triple clamps - as there is no movement there it really does not affect things like that. ie. We can lose a good 10mm from a tire wearing down with little or no affect.

    As for riding I find the handling on road in the twisties to be fine and given how well the bike handles anyway - it is great. The 21 is such a huge difference in the soft stuff though that it is incredible... You will love it or your rider will.
    #10
  11. erkmania

    erkmania I'll take better everytime

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    Very interested to read about the results; looks promising. Are there any concerns with the tire hitting the engine at full stroke? I ask because my numbers suggest that the 21-incher has an 0.8" greater radius than the 19" wheel/tire combo (r=12.8").

    Oh, I also calculated that the rake changes from 25.5 (stock) to 26.3 degrees (21-incher). I was too lazy to figure out the trail. :1drink
    #11
  12. Camel ADV

    Camel ADV Long timer Supporter

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    Pat is coming off a '93 R100 PD so he's used to the 21" front. This bike will be in the dirt more often than not so the slab handling isn't a real priority.

    I spent a bunch of time last summer on a '14 1200, and it was a great bike but I really noticed the difference offroad with the 19" compared to the 21" I'm used to. I have no doubt once everything is all wrapped up with this bike that it'll be night and day difference in the dirt, which sucks because Pat is already a menace and tough keep up with on his 22yr old bike :huh

    I was concerned about the tire hitting the engine too but if you look at this pic, the stock low fender should hit first but it doesn't. Looking at the fork angle and cycle suspension travel in your head it should definitely hit the front of the engine. Because of the arc of motion of the telelever, the front axle moves ahead when the suspension compresses. Everything should, if not, I won't have to work as hard to catch him :rofl

    [​IMG]
    #12
  13. Russ

    Russ Long timer

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    Speak to woody @ woody's wheel works Denver.
    I did the 21inch conversion on an earlier GS I just remover the front mud guard, it transformed the bike in sand, the trade off is that the front feels vague at high speed on tar.

    [​IMG]
    #13
  14. Camel ADV

    Camel ADV Long timer Supporter

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    You don't get any spray up around the triples? Looks like a mess waiting to happen to me!
    [​IMG]
    #14
  15. Camel ADV

    Camel ADV Long timer Supporter

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    Pat was really impressed with the SideKicker adjustable side stand I have on the F800. His 1200 was missing some parts (borrowed to repair bikes at the GS Trophy event in Sept) including the side stand so he went adjustable too. The SideKicker is expensive but very high quality AND the stock BMW one is almost the same price :eek1

    These things are great for uneven terrain, even better for an over height bike. Normally they are stock plus up to 3" but with a over height bike stock length is too short which is great if you try to use the stand with a lump under the foot and you still have a longer than stock adjustment too.

    http://www.aksengineering.com/sidekicker

    Right is the (well used) F800 version and left it is the shiny new R1200GS LC version.

    [​IMG]

    The pin, springs, bracket and bushings were all MIA too so the bike got new ones. The stand at stock length:
    [​IMG]

    Extended 3"
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    Now this next addition is a bit contradictory to the rest of the project. As I mentioned this is basically intended to be a big dirt bike rather than an ADV tourer. Despite the additional weight, Pat likes to run pannier racks not for luggage but as rear crash protection. He decided on Happy Trail SU racks. They're pretty stout and appear to be very "crashable".

    [​IMG]
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    Have decided on Altrider skid plate with upper and lower crash bars and Altrider rad protection too.

    I ordered Highway Dirt Bikes hand guards off the website but they canceled the order and refunded my money. I guess they don't offer them for the R1200GS. Haven't decided on a new brand yet. Because of the cylinders sticking out the sides, the bars take much less impact than a regular bike so ultimate strength isn't required. We're open to suggestions.
    #15
  16. pistole

    pistole Long timer

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    you're gonna need a decent set of footpegs as well
    #16
  17. NLS

    NLS My bike needs washing...

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    subscribed out of curiosity...
    #17
  18. NZRalphy

    NZRalphy I'm not half as good as I think I thought I was

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    Barkbuster hand guards are strong.
    Fastway foot pegs are open so mud falls through.
    Start jettisoning stuff to Loose some weight !
    #18
  19. Camel ADV

    Camel ADV Long timer Supporter

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    Half the fun of competing in the ADV class is racing with woefully inadequate equipment! Anyone can race a 220lb dirt bike with 12" of suspension but it takes a real jackass to race a 500lb bike with 7" :rofl
    #19
  20. NZRalphy

    NZRalphy I'm not half as good as I think I thought I was

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    Ok I'm with you now.:clap
    #20