Boxerworks R80GS Build

Discussion in 'Airheads' started by Nathan@Boxerworks, Aug 27, 2019.

  1. Nathan@Boxerworks

    Nathan@Boxerworks Adventurer

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    I think we have a another one left. We bought them overseas and use them on lotsa stuff. We can look tomorrow and see if we have another head lite guard, thanx
    #21
    Jim K in PA likes this.
  2. The Jester

    The Jester Long timer

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    Hi Nathan

    Nice bike!

    Is that the 120/90-17 TT TKC on the rear or the 130/80-17 TL? How is the clearance? I have the same suspension and wheels set-up on mine and want something more aggressive than the 110/90-17 MT60 that it came with. There's not a lot of clearance and so much variation between the actual measurements of different tyres compared to the quoted size - I don't want to buy a tyre and find it doesn't fit.

    Can you also tell me about the rear mudguard - I'm assuming it is the baja but how did you modify it? I like the reduced rear overhang compared to the stock which, to me, always looks like it extends too far back. UFO seem to offer lots of choices but not sure which is the best option.

    Thanks
    #22
  3. Nathan@Boxerworks

    Nathan@Boxerworks Adventurer

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    Thanx for the note The rear tyre is a 130/80/17 TKC 80. The Ohlins is a stock shock w clearance in the resting position(ie on the center stand it is about 10MM w the weight of the bike the clearance is about 1/2 that but I have done this several times and had no issues.) If u load the bike bag wise and put another person on it, the stock Ohlins spring on a full knobbie will just touch. I have this set up on my very modded 81 R80GS and just did a 6K mile trip out west fully loaded and ran a heidy K60 scout w no clearance issues. I had Hagon make me a shock w a smaller spring but the same rating for 2up on my GS and even w knobbies no issues.The rear fender came from Acerbis. We reshape it,then cut the front off the stock fender and install it to keep mud off the battery,and shock etc,as the custom fender is real short, so u need both fenders to make it work,There is no license plate bracket either. I did an R90S last summer into a mono shock and ran a 140 street tyre on it. I do not think u can offset the rim much more then the amt we do and have the bike handle correctly so spring choice and tyre profile are the solution Feel free to call and discuss if need be You can find us at boxerworks.org many thanx
    #23
  4. The Jester

    The Jester Long timer

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    Thanks for the info Nathan.

    I have a hyperpro remote reservoir shock on mine specified for my weight with +15mm ride height. I have checked for drive-shaft clearance throughout the full range of travel by removing the spring. Initially I had very slight contact under compression which would also have been an issue with the original shock. Adjusting the mono-lever a fraction to the right on the bearings sorted this.

    You mentioned the wheel offset - I was thinking about having Haan rebuild the wheel with an offset 18" rim but if it is possible to fit a 130/80 TKC there is probably less need for this. How far can the 17" rim be offset and is this just from adjusting the existing spokes? My closest point clearance is between the tyre and the arm rather than with the spring. I probably have less than 5mm clearance with the 110/90 MT60 but the tyre actually measures closer to 130.
    #24
  5. Screaming Chicken

    Screaming Chicken Long timer

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    Haan managed 3 mm max offset on mine with a fully rebuilt GS wheel, which is not that impressive.

    Not at all sure whether that’s the absolute max, or Haan, or my specific parts.
    #25
  6. Nathan@Boxerworks

    Nathan@Boxerworks Adventurer

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    The wheel we built has the hub milled 17mm and the rim offset 15mm, giving us what we needed to make the 130 work. U can put one or two 1mm,4 hole spacers that BMW make to move ur wheel away from the swing arm. I think I used "K" bike spacers on my wheel which was the first one I did about 6 years ago to fine tune the set up
    #26
  7. Nathan@Boxerworks

    Nathan@Boxerworks Adventurer

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    read my reply to ur last thread, thanx
    #27
  8. The Jester

    The Jester Long timer

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    Was that with a 17 or 18 rim?

    I think the previous owner had 21mm milled from the hub but I will need to search for the thread where he described the process of fitting the rear end. I am aware of the spacers - motorworks sell used ones relatively cheaply so no great issue there. I'm assuming that you now have a gap between the hub and the final drive - has that caused any issues or have you found a way to address that?

    15mm is quite some offset on the rim. I expect that required new spokes? Were there any further modifications to ensure the spokes were not under stress from running at a different angle? I have built wheels before (but not cross spoked). Would it be possible to offset the rim just by adjusting the current spokes?

    It sounds like I would be better having the 120 tyre as my target rather than the 130. Mitas offer the E09 in a 120/90 TL which would be a nice aggressive tyre but last time I fitted an E09 I'm sure the tyre was quite wide when fitted. The problem seems to be some manufactures quote tread width while others quote carcass width which, by the time you add the side knobs, can be way off the actual width.
    #28
  9. Screaming Chicken

    Screaming Chicken Long timer

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    Stock 17” cross spoke rim.
    #29
  10. Nathan@Boxerworks

    Nathan@Boxerworks Adventurer

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    I first did this wheel mod 7 years ago on my own bike.I would guess 50k miles ago at a minimum.No issues w the 15mm offset or the space between the hub and rear drive.I ride this off road every week and for many years two up w loaded panniers.I do not know if all the spokes are of stock length, but have done this on several occasions w No issues, and the bike has been across the country and 2up loaded 5 times, since the mod, so I would say it is a pretty robust set up!!----- Message truncated -----



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    #30
  11. sky44

    sky44 Gummikuh

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    utterly glorious.

    any other info on that twin headlight R100GS? I'd love some close up pics of the dash and light mounts.....

    also - I already hate myself for asking- but what's a restoration like that R80G/S cost? Like turnkey? 20k? yall finance? :D
    #31
  12. Nathan@Boxerworks

    Nathan@Boxerworks Adventurer

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    The twin head lites are on my R80GS in the pic. Looks like an R100 I guess cause of the R100GS front end, and is that the bike u want dash pics of or the Gray bike we just built? On the cost , lots of variables, but I would say 15K$ to 20K$ is correct. Given that we had the crank out of the engine so it was a ground up rebuild, and the trans was also rebuilt ,if u did not need that a bit of $ would be saved. If u are wanting an R80 built like the grey bike or an R100 done, a good bit of the build cost on an R80GS is in the complete r100GS front end, the modded rear wheel, and then the purchase of a 4 lug rear drive to fit the R100 wheel, both done of course to be tubeless on both ends. We are currently taking a r100GSPD and making it into the early R100GS looking bike just like the R80GS w the small head lite and sparse dash and small fairing. We also build our own exhaust systems.The one on the Grey bike is from Germany, and pretty pricy . Our systems are about 3/4 the cost of the one pictured on the Grey R80GS and we can make them look any way u want! Thanx for the interest
    #32
    sky44 likes this.