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Discussion Starter #1
I managed to get my wife on the back last night, had to as someone knifed a tyre on the cage.

I've had the sister inlaw on the back (130lb) & my kids both around 50lbs with no trouble. (not all at once ::))

But the missus weighs about 180lbs :-X & anything under about 20kph was darn right dangerous, head shake was unbelievable, the slightest twitch sent the bike wallowing all over the place.

I recently dropped the front end to fit clip ons under the tripple, which has no effect but to corner better with me on.

But wholy schmoly, darn right dangerous 2 up with the missus.

What's the go?
is this because i've dropped the front?
 

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Re: Wooooahh

reduced trail from the fork lift and CG translated vertically and aft with a passenger. wobble is an eigen mode of the
(rather complicated) equations
of motion of the bike, and all these things can have
(usually adverse) effects.
 

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Re: Wooooahh

Simple answer:

You need way more rear spring with that much extra weight on back. If you have any preload left on your current setup, you could try dialing more in but you won't get it "right" without a stiffer spring.
 

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Re: Wooooahh

I agree with Don; more preload or more spring. Had my daughter on the back (about 130 lbs) or my wife (about 140 lbs) with no problem. Had another friend (about 160 lbs) on it one time; lots of instability. Now I gotta find a spring adjuster!

Eddie
 

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Re: Wooooahh

Atkins baby, atkins! ;D
 

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Re: Wooooahh

Sorry. It was way to easy. we can't all be PC. I am 5'6...so if you guys want to throw out a bunch of "booster chair" "stilt" or "elevator shoes" comments feel free. I have it coming. no hard feelings...i just couldn't resist. :-*
 

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Discussion Starter #10
Re: Wooooahh

Thanks for the input Guys, feel better that it's a common problem with too much weight.

I think from memory factory setting is 6 notches out from closed on the preload, i think i'm on 5 now.

So i reckon the solution is take it into 4 or 3 & Leave the Missus at home (Sorry Darling :-[)

Maybe look at getting a flash aftermarket rear shock with that seperate little gas canister.

PS: I'm about 230lbs so with the extra 180, puts me at a total payload of 410lbs :eek:
 

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Re: Wooooahh

No no no no.

The clickers are for compression and rebound damping (you should have only rebound on the stock unit). Adding an aftermarket shock with an external resevoir adds (if supported) a compression damping adjustment.

PRELOAD is how much you wind the spring down. On the shock it's done with two threaded nut$ on the shock body.

You back off the lock ring and crank down the adjuster. Then re-tighten the lock ring.

At 230 lbs I can assure you that you need your stock shock ste to MAX preload. It will still have too much dynamic sag unless you get a stiffer spring. At 410, I think you've exceeded the load rating of the Monster ;)
 

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Re: Wooooahh

Anybody know the reccommended load rating?
 

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Discussion Starter #14
Re: Wooooahh

Hey thanks Don,
i'm really not ophay with suspensions adjustments. Can i just pick your brains here?

The little screw that takes a big flat screwdriver, that clicks every time you turn it? It says in the book that the std setting is 6 clicks out from locked up, i'm running on 5.
Is this OK or should it be different?

The Spring compression between the top & bottom nuts as it is now is 17cm. There looks like there is only another 10 or 12mm of thread left to compress it further. Is this normal?

Look forward to your reccommendations.
 

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Re: Wooooahh

The screw is the rebound damping adjuster. You're close the the factory recommended starting point as you say.

There's unfortunately not a lot you can do with this. Push your bike down sharply and watch how it recovers (rebounds). It should come up quickly, but not over shoot (go up past equilibrium and settle back down; i.e. it shouldn't bounce.

What you're really looking for is the least rebound you can run without the suspension "packing" over a rough road or series of bumps; not really an easy thing to learn to feel. Packing is when the suspension doesn't rebound sufficiently from one bump before you hit another. Through a series of such bumps, the bike gets lower and lower and can eventually bottom, even though no individual bump was sufficient to cause bottoming. If you ride over a moderate single bump, you can try to sense bouncing, and add damping if you do. Fully screwed in is max damping, backing the screw out reduces damping ( I think, check your manual for sure).

As for the spring preload, what you describes sounds roughly like factory setup.... appropriate for about a 160 lb rider! There are a couple of online resources describing the correct way to measure sag and adjust preload appropriately. I couldn't find any just now. This Ohlins manual has good theory and a very brief set-up guide: http://www.ohlins.com/pdf/07241-02.pdf

As I said earlier in this thread though, I'd bet just about anything that for your weight, if you still have the stock spring and shock, you need the preload cranked all the way down!
 
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I dunno - I'm 245 and I'm using the stock spring with the rebound about 2/3 to max. I've set my sag (yes .. with me on the bike) and checked it a couple of times since new and it's ok. A stiffer spring would reduce the amount of preload I need, but that's not a big deal I don't think.

When I put my gf on the back (115lb) the bike still feels ok - no wobbles like you're talking about, but just a bit of a different feel.
 

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Re: Wooooahh

Maybe the difference is that you have an ST-framed monster and I have the 851 framed bike.

BCM set me up and my preload was maxed with me on without gear. I'm 190.

I have no experience with the new frames. Perhaps they were set up with stiffer springs (relative to the geometry).
 

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Discussion Starter #18
Re: Wooooahh

Thanks Guys,
I'll have a "Play" on the week end. Try cranking the lock nut down to max & see how it goes.

Sounds like i might need a new spring, the old one looks a bit crappy anyway.

Will try & report the findings.
 
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