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98 R1100Rt rear spring

oldnslow

It's a way of life!
Is it possible and if so, who makes one, to just replace the rear spring on a 98 R1100RT. I don't want the whole shock unit, just want to replace the rear spring with a heavier weight rated spring.

I checked Race Tech, and they list springs for R1100S, but no RT.

Thanks
 
Found this but haven't used. www cannonracecraft com They catalog springs by dimension which would be helpful in some applications.
 
18000 miles. I'm a firm believer that most 'factory' or OEM shocks are severely undersprung for two up riding. The valving for both damping and rebound are usually sub par too, but the most important step for shock set up is proper spring rates. All the 'clicking' of clickers and 'dialing in' with the 'preload' knob can't fix an incorrect spring rate. And i think the 'preload' knob on the RT is nothing more than an adjustment for damping. But, with the right spring, this adjustment can be very effective.

I ride two up all the time, with a combined weight of 350 pounds. I know there is no way the stock springs, front and rear, are set up for that kind of weight.

I have learned from racing dirt bikes on a budget, proper spring rates are the best money spent for the most bang for your buck when it comes to handling and ride quality, so I want to fix my springs on this bike. Ohlins and the likes are way out of the question, but $120 I can do.
 
18000 miles. I'm a firm believer that most 'factory' or OEM shocks are severely undersprung for two up riding. The valving for both damping and rebound are usually sub par too, but the most important step for shock set up is proper spring rates. All the 'clicking' of clickers and 'dialing in' with the 'preload' knob can't fix an incorrect spring rate. And i think the 'preload' knob on the RT is nothing more than an adjustment for damping. But, with the right spring, this adjustment can be very effective.

I ride two up all the time, with a combined weight of 350 pounds. I know there is no way the stock springs, front and rear, are set up for that kind of weight.

I have learned from racing dirt bikes on a budget, proper spring rates are the best money spent for the most bang for your buck when it comes to handling and ride quality, so I want to fix my springs on this bike. Ohlins and the likes are way out of the question, but $120 I can do.


I agree, Springs are #1!
 
yeah, new springs will help, but those stock shocks are gonna be played out in another 15-20K regardless.

What is your test? With 62,000 miles on my 2002 R1150RT I don't feel any pogo-stick bouncing after a serious bump like a car with worn shocks.
 
they will wallow in corners, but should not. they sag, and require jacking up the pre-load just to get them to function. they respond poorly to road irregularities, unable to follow the contour of the road. and yes, they (often) pogo their way down the road.
i've seen it and felt it. ANY shock is well cooked at 60,000 miles, not just OEM (which are spec'd for nearly all bikes on a basis of cost, not quality). Ohlins and Wilbers and all the rebuildables will require a redo long before 60K.

hey, if you're happy with how your bike handles, fine and dandy. but for a comparison, try a bike equipped with top end components, and you will feel what you've been missing.
 
they will wallow in corners, but should not. they sag, and require jacking up the pre-load just to get them to function. they respond poorly to road irregularities, unable to follow the contour of the road. and yes, they (often) pogo their way down the road.

Afraid I'm still lost. To me wallow means the body of a car tilting side to side or end to end or both and the sidewalls of the tires flexing excessively. M/C suspension operating in only one plane with as stiff of components as we have can only move up and down with respect to the tire patch on the pavement. If it oscillates one end then the other like a hobby horse it's simply pogo-ing and of course it needs shocks. And sag is a function of the springs not shocks. Springs that have compressed over time have exactly the same spring rate (lbs/inch) as they had when new as long as none of the coils have already compressed against it's neighbor. I'm relatively sure that a low M/C corners better than a tall one as long as nothing drags so sag isn't a problem until that point. The only reason that I would increase preload would be to prevent excessive bottoming. The last thing I want is over-rigid springs passing more vertical motion to the unsprung weight of the M/C and me where the only force that will pull us back down and regain traction on the tire patch is gravity which seems to take forever when it happens. I can't imagine anything outside of third world motorbikes that would need lots of preload to simply get the suspension off the stops.
 
I'm relatively sure that a low M/C corners better than a tall one as long as nothing drags so sag isn't a problem until that point.

I can understand your thought process however there are many things which affect the handling of a motorcycle and ride height is one of them. Typically, a taller bike will turn in more quickly. Further, if a spring is sagged, say half an inch, then that has an effect on the geometry of the motorcycle. As an illustration, put a passenger on your bike with no rear spring adjustment and go for a ride. Very simply put, you've just increased the rake by compressing the rear suspension so you should feel a definite slowing of reaction to your steering input. There are many, many variables which can affect everything I've just said. I'm just pointing out some basics.

As far as shocks are concerned, in my experience the shocks on my "S" were worn out in fewer than 30,000 km. If the original poster is swapping springs, he may as well "spring" for a shock rebuild/revalve while they're at it.
 
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I have received this info!

Received this e-mail today...sounds promising.

"Yes. But you need a crazy tool to do it so you'll have to send me your
shock. Also I need your spring so I can check the rate, that is my
starting point. The new spring will be dark red, $110 + shipping.
Thank you,

Ed Sorbo
Lindemann Engineering LLC
909 838-4587"

Proper spring rate is important to keep the shock body and valving system in the 'sweet spot' of the shock. A spring that is too soft and the shock valve mechanism is already past the 'small bumps in the road' portion of its stroke and is entering the 'big bump' section of its damping forces. Thats a harsh ride.

A spring too stiff and, well we know what that feels like. Since the stock shock doesnt have a pre load adjustment on the collar of the shock, I will have to let Lindemann do his math and come up with the proper rate for my weight and riding styles.

For my amount of miles, the value of the bike, and my riding styles, A new spring is all that will fit my budget. I will investigate the revalving though, since he will have the shock there.

From his web page:

OEM without air valve

Rebuild, including oil & seals $250

Spring, add $110

Revalve, add $100

Total with everything $460
 
Some times the demands racing puts on parts is amazing. Reading an old Kevin Cameron column from Cycle World. He was only getting two races from Kawasaki 750 crank shafts. A hundred thousand hard miles on the street or 400 on the track. Take your pick. From other sources, want to have a fun weekend at the track in a replica Cobra? Budget for 4 tires. Shocks on Baja buggies in the same category I imagine. But shocks on street bikes? Easy to believe that manufactures won't spend the $$ for state of the art units or be able to accommodate loads perfectly from a jockey sized solo rider to a plus sized North American couple with riding styles from mild to wild. But I'm not ready to buy the idea that ALL shocks will WEAR OUT in less than 50,000 miles. I don't think that they are hammering at either end of the stroke, getting hot enough to blister the paint or being blasted by 100 mph Baja sand. Just a plastic piston in a steel tube with lots of good lubrication. I don't rack up many miles on a vehicle but my wife does. She recently sold a Honda CRV with 175,000 miles. Always had regular maintenance done at one of those places that has the words Service Center not Garage in the name. If they can find anything to sell, believe me they will try. Shocks or struts in 175K? Nope. Still going strong.

Just noticed that OldAndSlow and I are both from a place called the Show-Me-State. Somebody wants to make me believe shocks wear out quickly on street bikes they will meed to Show-Me and someone confusing springs and shocks is off to a really slow start doing it.
 
Im far from a shock expert, but, I am confident in saying that until a seal is leaking or a piston is damaged, or the internal oil is heated and its molecular structure is altered, a shock is not going to fail. (But how much thinner can the oil get, it is already 5w oil?) I have seen the shocks on local pro level dirt bike racers go multiple seasons on a single shock. What I do think can happen is the spring will wear out and sag more over time. But to wear out the shock itself in 30,000 miles of street riding, I too find it hard to believe.

But, I'm open to being educated.

I wish bike manufacturers would make the springs changeable by the owner. There is a big difference from a 150 pound rider to a 220 pound rider, when they are on a 700 pound bike. The spring rate is like night and day for those two riders.
 
To this comment, "Im far from a shock expert, but, I am confident in saying that until a seal is leaking or a piston is damaged, or the internal oil is heated and its molecular structure is altered, a shock is not going to fail."

True and not true. True, if that the shock has not blown the seal and evac'd the oil it is not "failed". NOT true in that a shock, especially a factory stock shock, DOES fail all damping in less than 30,000 miles. Sooner if consistently loaded more than a single rider. Shocks/springs, in stock form are one of the biggest compromises all OEMs put on these bikes, regardless fo brand name.

If you plan to keep the bike and enjoy it for many years, I would spend a bit more money and get custom, quality, rebuildable shocks, set up to operate in their mid-range, for YOUR weight, YOUR loading and YOUR riding style. With the shock properly tuned to operate in its mid-range for your conditions, you can easily fine tune it to your preferences.

Sure, some are quite expensive, like Ohlins and Wilbers (to metheir worth every penny), bot others like Hagon, Fox, and others offer more reasonable cost while still giving you the optimum operating range. I wouldn't spend much money on stock shocks myself. They just wont last as long.
 
Just noticed that OldAndSlow and I are both from a place called the Show-Me-State. Somebody wants to make me believe shocks wear out quickly on street bikes they will meed to Show-Me....

That's what some here are trying to do. Your choice if you want to ignore/discount the experience of others.

At the same time, some people don't ride their bikes in a manner which enables them to appreciate the difference between good and bad shocks. Doens't make them a bad person. Myself, and others, I can feel the difference in ride quality when I'm cruising down the highway.
 
Well, I'm a bad person :laugh and I have an '96 1100RT shock that has the oil spewing out of it with less than 20K miles on the clock! :p

I can take a picture of it for "show me" guys upon request. :stick

Now bear in mind it's 16 years old too. There is a lot of real world experience here on the forum indicating that BMW stock shocks are middle of the road at best. Motorcycle shocks just wear out a lot faster than car shocks do is another fact to consider.
 
back to our regularly scheduled program...

Back to my question..yes I have found a place that will replace my spring with the proper rate. Thanks for the help..

And, as a bonus, we discussed for two pages and not once was motor oil mentioned!:laugh
 
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