Bringing a K1100RS back to stock

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dwerbil
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Bringing a K1100RS back to stock

Post by dwerbil »

I bought a good running '93 K1100RS last May and have been bringing the bike back to its former stock self.
Photo day after purchase...
http://www.pbase.com/dwerbil/image/124642895

I discovered shortly after buying it that the bike has been lowered about a inch and a half. To bring the bike back to stock, I replaced the shorter rear mono shock with a stock one, and have changed the 17" five spoke rear rim back to a 18" three spoke. That change allows me to now get the bike on its centerstand. Another bonus...the speedometer and odometer now are just about spot-on in their accuracy.

The main issue left now is the front suspension and bringing it back to stock. I assume it's lowered a bit. The fork tubes appear to be at the top of the triple tree, so there's no lowering there. The next place I guess to look is the length of the fork springs. Does anyone here have the stock length the springs should measure? I'm guessing if the front has been lowered that its been done with shorter springs.
Thanks for any help.
Randy
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04 R1150RT ~ 78 R100/7 ~ 84 RS ~ 93 K1100RS ~ 65 R60/2
Randy in Round Rock
Matt
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Re: Bringing a K1100RS back to stock

Post by Matt »

Hi Randy, glad to see you here. Nothing I hate more than a perfectly good motorcycle getting lowered to substitute a little rider training & dedication Thats bound to stir up some debate...:)
Matt Richards
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The Veg
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Re: Bringing a K1100RS back to stock

Post by The Veg »

Since you can't stretch the springs...at least not very easily...why not just getcherself a new set of stock springs?
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dwerbil
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Re: Bringing a K1100RS back to stock

Post by dwerbil »

Since you can't stretch the springs...at least not very easily...why not just getcherself a new set of stock springs?
That's just it Veg, I don't know what the stock length is. When I open up the forks, I'll want to have that info to check what's there. :P
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04 R1150RT ~ 78 R100/7 ~ 84 RS ~ 93 K1100RS ~ 65 R60/2
Randy in Round Rock
dwerbil
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Re: Bringing a K1100RS back to stock

Post by dwerbil »

Hi Randy, glad to see you here. Nothing I hate more than a perfectly good motorcycle getting lowered to substitute a little rider training & dedication Thats bound to stir up some debate...:)
Matt, this forum looks like it's going to be a great one. Thanks for all your efforts.

I found out the bike had been lowered when I was installing a Ebay centerstand. It was impossible to get the bike on its centerstand. Now I know why it didn't come with one. At least now with the now stock rear mono shock and stock rim, I can fanagle it up on the centerstand. Correcting the fork springs would most likely help it even more.
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04 R1150RT ~ 78 R100/7 ~ 84 RS ~ 93 K1100RS ~ 65 R60/2
Randy in Round Rock
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Re: Bringing a K1100RS back to stock

Post by The Veg »

I think I see your point...you're not sure if the front is at the stock height or not...might be, but might not be...right?
Cogito Ergo Moto
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"A bunch of weirdos with old motorcycles can never be boring." -Doug West
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Major Softie
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Re: Bringing a K1100RS back to stock

Post by Major Softie »

Check the sag. If it's not sitting too far past full extension, then the springs aren't any shorter. Maybe someone here can tell you what their non-rider sag is right now. I only have a K75, and it might be different. If the non-rider sag is over 1-1/2" or so, then it could just be ol sacked springs, but it's probably shorter springs or reduced preload.

With (average weight) rider SHOULD be around 30mm or so.

Check the front tire too. Some people put lower profile tires on to drop the bike some.
MS - out
richard t
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Re: Bringing a K1100RS back to stock

Post by richard t »

welcome back ! do you still have the K75RS
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George Ryals
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Re: Bringing a K1100RS back to stock

Post by George Ryals »

If the front has been lowered as much as the rear was, riding the bike with the taller rear shock may get exciting (tank slapper). Especially getting on the brakes on a down hill run.
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Re: Bringing a K1100RS back to stock

Post by Major Softie »

Hey Richard!

That is still an unfinished project in my garage. I REALLY need to do something about that.
MS - out
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