Centre Stand scrape

[ednap]

I guess the centre stand is the lowest section of my R1150RT as it is what scrapes the road first on heavy cornering. Even worse when two up despite altering the rear suspension loading.

 

Is there a way to improve the ground clearance?

[ShovelStrokeEd]

First a set of premium shocks seems to help quite a bit.

 

Second, a slight modification to your riding to allow your upper body to get down and inside on corners. That will allow the bike to proceed through the turn with less lean angle for the same speed/radius.

 

Finally, you could probably persuade our fearless les...., errr, Rider, to come to Aussie and conduct a Riding Smart seminar.

 

Speaking of which, I haven't been reading the Ride and Event Planning section much, are there any planned for this year?

[Ken H.]

Speaking of which, I haven't been reading the Ride and Event Planning section much, are there any planned for this year?

Nope.

[ednap]

Thanks for the reply.

 

Just exactly h ow does more expensive (better) shocks help? Sorry to sound dumb but I have often thought about the ohline or similar but at AU$1500 or more I just do not understand what extra they would really provide. It has got to be more than simple ground clearance right? Obviously I have not messed with the suspension of any of the bikes I have owned. Always thought the guys that designed the bike got it right or pretty close.

 

Appreciate some plain english explanations.

 

Thanks

[ShovelStrokeEd]

Ed,

Yeah, it's much more than just simple ground clearance. The suspension of the bike must move to allow it to ride properly. How that movement is controlled is the key. The stock suspension is, at best, a compromise between smooth, soft ride and some measure of control. The difference between a set of properly sorted, premium shocks and the stock stuff is like night and day.

 

To start with, your stock suspension is aimed at a 170 lb rider with minimal luggage. You can compensate somewhat for heavier loads with spring preload but it doesn't compare to a proper spring rate to begin with. A proper spring will allow the wheel to move through its full range of travel. Good damping will control the way in which the wheel travels through its range of movement allowing the bike's chassis to remain stable the while.

 

These adjustments, spring weight, sag, and both compression and rebound damping are all available on premium shocks and, when properly set up by a fitter who knows his job will completely transform your motorcycle. Not saying you still won't ground the center stand, just that it won't be because the stock suspension was inadequate to control the wheel movement under the cornering forces and road irregularities that are part of everyday riding.

 

It will probably ride a whole bunch smoother as well.

[Hulka]

How well are the "Ohlins Shocks" that I see advertised in the BMWMOA and other magazines? Are they worth the money if you are going to replace your shocks. My friend and I were talking about this the other day if they are worth it. Neither oe of us has ever used them just seen them advertised.

[ednap]

So the setup of premier style shocks to suit the rider is just as important as the actual shocks?

[Ken H.]

How well are the "Ohlins Shocks" that I see advertised in the BMWMOA and other magazines? Are they worth the money if you are going to replace your shocks.

The suspension is the weakest link of a RT. Any aftermarket shock, including to Ohlins, is a worthwhile upgrade.

[bmwmick]

I guess the centre stand is the lowest section of my R1150RT as it is what scrapes the road first on heavy cornering. Even worse when two up despite altering the rear suspension loading.

 

Is there a way to improve the ground clearance?

 

Ed,

Read through this:

http://www.seatrider.org/techntips/rear%20shock%20preload.htm

Pics: http://members.cox.net/slartidbartfast/bmwfix/shock-oil/shock-oil.htm

You 'may' just need to add some hydraulic jack oil to your preload adjuster. If you have no resistance in the preload adjuster knob for several turns, you need some oil.

This will NOT restore a dead shock but it will allow you to set the static preload height.

 

Mick

[Voyager]

So the setup of premier style shocks to suit the rider is just as important as the actual shocks?

 

Yes, but to be fair it's not rocket science. I bought my bike used with Ohlins already installed by the Ohlins tech for the previous owner. That being said, adjusting the shock from the PO's weight/height to mine was not that tough, nor was dialing in the rebound and compression dampening. It only takes a little bit of trial and error front and rear to come up with a good solution for you.

 

An additional feature of Ohlins vs. stock not already mentioned is the adjustable length on the rear shock. A small adjustment of this gained me some ground clearence and leg room, though I'm sure taken to the extreme it would have negative effects on the rake anlge of the forks. I had previously dragged center stand when fully loaded, though I wasn't "bottoming" the spring.

[USAF1]

I can personally tell you that after putting the Ohlins on, that the bike is much more "on-line". Not wallowing around/thru/over the bumps anymore. When I ordered these, I had them install a much heavier spring, and then gave it another 23 turns for the preload (this was AFTER doing the setup). World of difference from the OEM...and I was running it with the preload at MAX!

 

Pat

[Haynes]

Ed,

The Ohlins shocks are not too expensive in the long run as they are rebuildable. The OEM rear shock is a bit over (AUS)$900 and the Ohlins in something like (AUS)$1400. Assuming that the OEM shock life is around 40,000km, it will then need replacing. The Ohlins, at the same distance, will need a rebuild for about (AUS)$450 making the long term price slightly cheaper.

 

I had an Ohlins on the rear of my RT that was written off after only 400km of riding since the change. The dealer kindly replaced the Ohlins with my worn BMW shock before the bike was taken away by the insurance company. I still have it stored in a box and I'm waiting for my rear shock on my '04 RT to show signs of deterioration before it goes on.

 

Was it worth it? ... It depends on the type of riding. If you're a sedate rider and mostly travel solo, I'd stick with the original shock until there was a need for a change. If you ride aggressively or travel two-up and like to perform a bit in the corners, an upgrade is worth it.

 

I originally replaced mine after the bike showed signs of moving wide on a few tight bends on the way home from work. I ride these bends every night and have learnt the feel for them. Once the Ohlins was fitted, I could tell the difference by the better behaviour whenever there is suspension bounce. It was clear to me that there was a vast improvement but remember that I was comparing a worn standard shock to a new high performance shock.

 

My advice is to wait until the OEM shock has done is time before replacing it. Until then, slow down on the corners.

[ednap]

Thanks for all the replies, advice, suggestions and information provided.

 

I will certainly check the oil in the adjuster but I know there is some adjustment there as I can feel it when I screw it up for the weekend rides. I also note that the ride height is different (higher) if I forget to adjust it back after the weekend rides.

 

I wouldn't call my riding style aggressive, not overly fast but I do like to lean into the bends. I do ride my bike 1 up every day (90km or 56 miles) to and from work and most of my weekend riding is 2 up with my light framed wife on the back.

 

On my daily ride I notice on a slow left hand sweeper with a depression mid way through the corner my centre stand scrapes as the bike drops into the depression and the suspension absorbs it. Hard to explain. This is in 1 up riding and I'm not leaning heavy into the corner. BTW I'm about 82 kg (180 lbs).

 

I'll do a bit more reading and also check the loader oil level as suggested. My bike has done 24'000 km (15,000 miles) so maybe when the time for shock overall arives I will upgrade to a performance unit.

 

Thanks again for your input.

[Voodoo]

For what it's worth, Ed. I've upgraded my suspension and it has made a difference. It hasn't stopped the bottoming altogether - if you're loaded up and hit a compression mid-corner, you're still going to bottom the center stand, or side stand, or valve cover, etc. depending on where you are in the corner and how you are on the bike.

 

That being said, the suspension upgrade was the most worthwhile upgrade I've ever made to the bike. I'd give back all my other accessories, bits, pieces, doodads, bolt-ons, you name it, before I'd give back my new shocks. I'm not saying you should run out and plunk down $1,500.00. But if the OEM suspenders are even close to being worn out, it's a no-brainer.

[Graham UK]

David,

On my 1100rt, I have noticed an adjuster on the rear arm, below the spring with a srewdriver slot in it. The word "tension" underneath.

Can you tell me what this is for, does it alter the suspension in any way?

My bike is "all stock".

Thanks,

Graham

[bmwmick]

Graham,

That is the 'rebound' adjuster. It controls the rebound only.

IN makes it stiffer on rebound and OUT makes it softer.

 

Mick

[Boffin]

David,

On my 1100rt, I have noticed an adjuster on the rear arm, below the spring with a srewdriver slot in it. The word "tension" underneath.

Can you tell me what this is for, does it alter the suspension in any way?

My bike is "all stock".

Thanks,

Graham

 

That is the rebound damping adjuster, standard setting is 1/4 turn clockwise. Turn left to reduce, right to increase rebound damping.

 

Andy

[FlyingFinn]

Now that we talk about rebound settings (the only damping adjustment in most stock motorcycles).

 

Why is "more rebound" mentioned in many sources (magazines, DBs, camp-fire talk etc.) as something you dial in for track riding or fast session through some back road?

 

If "more rebound" means more damping i.e. slower rebound, why is that prefered for fast(er) riding?

 

I would think the faster the tire moves over a bump on the road, the faster it needs to rebound to not loose contact with the road surface...

 

--

Mikko

[ShovelStrokeEd]

Mikko, your correct with the caveat that it should only do it once. Rebound damping is intimatly tied to spring rate and unsprung weight. When looking to set up a suspension, the first thing that has to be right is spring rate so that full range of motion is available to the suspension. After that, compression and finally rebound damping are set to match rider preference and road conditions. There are guidelines for this but basically, too little rebound and the bike will tend to pogo over bumps, too much and it will want to squat. Neither behavior is conducive to orderly progression down the road, especially over bumps. It gets complicated when tuning both ends unless the baseline settings are pretty close as there is interaction going on. For expample, too harsh a compression damping on the front can lead the rider to think he needs more in the back. That's why suspension guys get big bucks on factory teams.