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Normal Topic A "fork in the road" decision to make. (Read 326 times)
Tony Smith
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A "fork in the road" decision to make.
04/04/19 at 22:38:54
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I have probably bored a lot of people near to death in this group with the saga of fitting a K100RS front end and a 860cc kit to my R65.

I have further modifications in mind.

Firstly I intend to convert to a hybrid "monoloever" using an early G/S swingarm and a K75 final drive (lets me keep drum brakes and the ratio is a bit kinder than the K100's.  This will necessitate fitting a long wheelbase sub-frame to accommodate the second major modification I plan.

Which is to fit the fairing, tank, seat, ducktail and (with mods) the fairing lowers of a K100RS to the thing.

I think that the resulting confection will be pleasing to the eye and I am sure it will ride even better than it does now.

But, it ain't gunna be an R65 anymore. In any event whilst the front end and plastic are reasonably easy to reverse, fitting the monolever rear end will require structural modification to weld in the shock upper mount  (The idea is to have matching front and rear wheels along with a wider rear wheel - something around 130/80-18 instead of the current 110.90-18.

Bluntly if at some point in the future I, or a subsequent owner wants to reverse the mods and turn it back into a "true' R65 that could be done relatively easily except for the monolever which would require considerable (reverse) engineering.

My musing to the group is - should I retain the original front end, tank, seat, sub-frame, swing arm, final drive and wheel, or should I accept that this is a one-way street and sell off the swapped out parts? I have in the past said a number of unkind things about "cafe" and "custom" builds - my conscience is clear in that the bike will still look like a BMW and its basic functionality and purpose will not be impaired.

So, please give me arguments one way of the other regarding retaining the ability (even if somewhat theoretical) to return to standard.

  

1978 R100RS| 1984 R65 | 1992 KLE500 | 2002 R1150GSA
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Justin B.
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Re: A "fork in the road" decision to make.
Reply #1 - 04/05/19 at 21:54:42
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My mind splits as well.  If someone runs across a very nice original bike it seems a shame to hack it up.  On the other hand, if what you started out with has seen better days then I would consider it fair game.

Someone on this forum did just what you are proposing years ago but I can't remember who.
  

Justin B.

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1981 R100RT - Summer bike, NEKKID!!!
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ged in oz
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Re: A "fork in the road" decision to make.
Reply #2 - 04/06/19 at 03:22:29
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I haven’t been bored to death with the front end and 860 kit info Tony. I’ve been going over it all very keenly and picking up loooots of info! They are all interesting, doable and practical mods that may make it a little less R65, but it’s probably a much better bike for all the work, thus the reward for doing it.

Frame chops for Muppet Racer ‘builds’ are hmmm, really unfortunate.... Anyone old enough to remember the Easy Rider inspired crazzze  of “Chopperising” in the 70s with raked steering heads and extended forks with hardtail conversions, can see that we’re unfortunately entering the same sort of phase. There were so many beautiful old British bikes that met their end through that era... Having owned a rigid framed Beesa for 25 years, I have no idea why you would ever want to convert a swinging arm frame to a hard tail!

The difference with your dilemma, is that you are changing a frame in order to make it perform better, provide better tyre choices and suspension options to match its new output etc etc etc. That’s a really different proposition to chopping a frame up because, well.... you think it ‘looks better’, despite the fact that it doesn’t perform as well, or as safely or as comfortably as it was before you started. To me, that’s a really genuinely objective improvement versus an entirely subjective choice.

Funny thing, but in my search for original bits to de-Rat my ‘Rat Bike’ that I’m working on, I ran across this guy, about an hour down the road from me.

https://rooneycycle.com/

If you want an example of objective improvement versus subjective modification, it underlines my point entirely. My mind got blown.....

Paul was a good source of original bits for me! and he has a few spare frames as well! but he is certainly well aware of how important all those original bits are going to be to people like me in the future, returning R65’s back into R65’s! Mind you, they won’t be returning Paul’s bikes back to standard, or probably yours either.  Smiley Smiley Smiley







  
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skippyc
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Re: A "fork in the road" decision to make.
Reply #3 - 04/06/19 at 17:29:54
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Like the others I am waiting to see how it all turns out.
I dought it will ever be changed back to standard, as R65s are not going to be highly sort after collector bikes. Just my opinion.
  
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marcmax
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Re: A "fork in the road" decision to make.
Reply #4 - 04/06/19 at 23:03:17
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I am of the opinion, it is now your bike do with it what you want. Make it work for you and enjoy the journey. While they are fantastic pieces of machinery, they were never meant to be highly prized pieces to be collected. They were meant to be ridden, used and modified to fit the need. In my opinion you are honoring the designers original intent. Make it yours and never look back!
  

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1982 R65ls        1984 R65ls        1991 K75
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Re: A "fork in the road" decision to make.
Reply #5 - 04/08/19 at 03:31:07
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Nice words marcmax, I'm also of the opinion it's your bike Tony and you do with it what you like. As far as the pieces go, if you want the money for them then sell them, you're a competent wrench able to make the changes work and it's unlikely you'll want to resort back to it's original form.  (Unless it actually rode better then  Smiley)  Plus you've got a big brother that's much more capable than the R65 so I say have some fun with it too.  I've been eagerly awaiting your thoughts of the 860 upgrade, have I missed some posts about it?.

I'll probably do something to mine when (or if) I get another bike to take over from the main touring duties the R65 currently fulfills. I've spent five years considering changes, haven't had the urge to start but always felt I'd make use out of it being a scrambler.  Unfort. I missed out buying R100GS forks in the local version of ebay recently which would've been a good start.
Reading your K100 front end conversion made me aware of what's involved to fit different forks so I've found it interesting reading too. Of course there would've been the issue for me of triple trees and finding a front wheel.  Tony, have you tried boring out triple trees to fit larger forks or know it's possible?  I imagine the clamping gap would be a headache for machining attempts.

If you end up selling the parts, I'd probably buy a few.
  

 1985 Black R65  -  1983 Ducati Pantah 500 - 2001 DRZ400 dirt only
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Tony Smith
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Re: A "fork in the road" decision to make.
Reply #6 - 04/08/19 at 05:47:57
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tunnelrider wrote on 04/08/19 at 03:31:07:
have you tried boring out triple trees to fit larger forks or know it's possible?  



firstly, you have not missed nay posts about the 860cc conversion, I have been leaving Adrian with clear air as his journey has been longer and more arduous than mine. But there is stuff I am dying to say, so he is on a countdown.

As regards boring the triple clamps, I would not even try unless the difference was absolutely trivial, say 1mm or so. The reason is that I do not know enough metallurgy to know what the strength of the  existing part is, nor do I know the required strength. That gap in knowledge tells me to use alternate stock parts and not mess with machining high stress components.

I have a friend who has recently completed converting an R65 into a pseudo R65GS - My wife sold him her G/S single seat that has graced her R65/80 for a few decades and the later GS single seat rack system that was also fitted to her bike int he past. For a front end Brian used a DRZ400 complete front end - he pressed out the steering axle and then had the DRZ triple trees machined to suit the R65 steering axle. An R75 rear wheel looks a natural and it all seems to work very well for him. He is also going to do an 860cc conversion, but the way I now wish I'd done mine - more of this in the next few days.

Much as I love the GSA, I would really have preferred it to be a Bumble Bee, or, better yet, a R100GS "Flintstone". But the problem is that I could have bought two GSAs for what those airhead models command..


  

1978 R100RS| 1984 R65 | 1992 KLE500 | 2002 R1150GSA
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tunnelrider
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Re: A "fork in the road" decision to make.
Reply #7 - 04/08/19 at 07:00:55
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Interesting as ever, thanks for the reply Tony. I didn't think it would be realistic to bore out the triple clamps much. Your friend's pseudo R65GS conversion, I've read and seen a little about putting DRZ front ends on airheads, seems to be the most common front end conversion for getting better off road use out of a non GS airhead. Funny I've got a DRZ too.  Glad it's working out well for him, it's good to hear. I look forward to more 860 tales.
Tony Smith wrote on 04/08/19 at 05:47:57:
Much as I love the GSA, I would really have preferred it to be a Bumble Bee, or, better yet, a R100GS "Flintstone". But the problem is that I could have bought two GSAs for what those airhead models command..


Yes I know what you mean - the last time I saw a Bumble Bee for sale in NZ about five years ago it went for $6100 I think, may've even been $6800, with a spare engine. The auction started at $5500.  Is the "Flintstone" the R100GS-PD?  An R100GS comes up every now and then here, usually $5-7K.
  

 1985 Black R65  -  1983 Ducati Pantah 500 - 2001 DRZ400 dirt only
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