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Discussion Starter #1
Just got my suspension setup at a bike shop. I can feel the difference, for the better, but I noticed that the right preload adjuster sticks out about three millimeters more than the left. My common sense says this is wrong. Take it back in, right?
Also, apparently I'm at the limit with the preload on the front. If I get any heavier, or any more gear, I'll need heavier springs, so I've been told. Also, I'm still experiencing a lot of dive during medium-hard breaking. Should I just get the heavier springs now?
 

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If they're not even, you've got more preload available.
The preload adjusters should be set even. Either take it back or even 'em up yourself.

Are you using all of the front suspension travel?
 

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Discussion Starter #3
Hi Nick,

I just started learning about suspension this week, man. The guy at the shop said the front preload was set at its limit. I was afraid he was just trying to sell me some heavier springs. How do I know if I'm using full suspension travel? Is it safe for me to bring the lower preload adjuster up without adjusting anything else? Or should I bring the higher adjuster down?

Thanks.
 

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I agree - even them up yourself. Put a tie wrap on the fork slider and see how much travel you are really using. You want to use as much as possible without ever bottoming out. My stock non adjustable Showas were really soft and compliant, but never bottomed and had about 10-15mm in reserve travel. They worked great on street and track. I've since swapped to adjustable Showas from a '96 SS and am still backing out the preload adjusters to use as much of the available travel as I can. I may even have to swap to slightly softer springs - but only after a bunch more adjusting and testing.

The more compliant the suspension is and the more closely matched the damping is to the spring pressure, the better the suspension can keep the tire in contact with the pavement. And that's what it's all about. Stiffer is not always better. Neither is mushy. If it doesn't bottom out, doesn't chatter under braking or on washboard pavement at ridiculous lean angles, and doesn't jar your spine or teeth on hard bumps, you are in the ball park. From that point on you riding experience will help you sort it out.
 

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Was the adjustment made to cure the unstable front end? What was the deal with the warping brake rotors? Did the bike shop give you any thoughts or advice?
 

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Conventional wisdom has it that the Monster is sprung for a 155-160 lb. rider. If you're heavier (as most Americans are), you do likely need stiffer springs. The stock on my '99 900S was .8 kg/mm. With those springs I had the preload maxed, meaning that I'd given up a fair amount of travel.

I now have RaceTech .9 kg/mm springs with preload minimized.

Short answer, I'll bet your shop was not selling you a bill of goods. You probably would benefit from stiffer springs.

Also, the forks should be matched in preload. It's disturbing that they're off by that much. I'd question the quality of the shop that did that to you! Someone needed a jolt of cafiene.
 

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Discussion Starter #7
Was the adjustment made to cure the unstable front end? What was the deal with the warping brake rotors? Did the bike shop give you any thoughts or advice?
Jiro, the second time I thought I had warped rotors, the dealer said they actually were not warped, but the brake pads were "malformed" or glazed. The dealer put new pads on, the ones that go on the S4R (I'm not sure how the compound is different from the M1000 stock pads). They work great, and I broke them in just like Ryan (terrible_viking) suggested I'd do in a past post.
That was before I had my tankslapper incident. I now attribute the tankslapper to my rider skills; just too much power out of the turn, over some light bumps on the road due to water falling on the asphalt from the top of the tunnel entrance. I got the suspension set up at another shop (not the dealer), hoping it would help prevent any future front end instability.


Thanks for all the comments guys. It's great help.
 

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Discussion Starter #8
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I now have RaceTech .9 kg/mm springs with preload minimized.
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Don, can I ask you what your weight is, and how you like the .9 springs? If you have the preload minimized, does that mean that if you loose weight, you have to get new softer springs again, or do you have enough room to play?
Thanks
 

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Hey Jarik,

Do you have Brembos? I do... I spoke with someone a few weekends ago who suggested that Brembo uses really agressive pads and that those can cause temporary warpage if you don't warm the discs up slowly. Dunno if there's anything to it, but now I refrain from braking really hard on the Monster the first few stops into each ride and the pulsing of the front brakes (slight warpage??) has indeed gone away.

If your problem was glazing of the pads, you should probably be fine now.

Your forks should be set evenly. I had a bunch of suspension links saved somewhere, I'll re-pos them as soon as I find them or do a search for suspension on this board. Lots of good stuff should come up. Set the forks as soft/ compliant as you can get away with, chances are the springs are too weak for you.

I had a rather unexpected tankslapper on a freeway onramp in Santa Monica on my way to the shop last Thursday myself, putting a new nick in my Cycle Cats where they hit the damper bracket. I recovered but scared the [email protected] out of the lady behind me. Just when I thought I had my suspension sorta sorted out...

Good luck,

-R.
 

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As some point of reference, the (OEM) front springs on my S4 are 0.85 kg/mm units. They seem about right for me, I'm about 170 lbs with all gear, with sag set at 1.25" on the front.

Pretty bad bumps leave me with about 3/4" of travel left.

Beware using Zip-ties, use the tiniest ones you can find. Dunno about the M1000 forks, but on my S4's Showas, the forks at full bump go far enough that the 'head' of a normal zip tie will crunch the seal.

As far as the rotors go, there are a couple of folks here that have warped the stock ones, just as T-Vik described. Method to minimize warpage is as he described also.
 

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Discussion Starter #11
OK, just heard from the shop that set up my suspension, and they said to not touch it. Leave the preload audjusters as they are (uneven by 3mm). "On a Monster" they are supposed to be even, but they never are, I was told. I trust these guys, but I also trust most of the guys on this board. Is it possible that one shock needs to be adjusted differently than the other to make them both handle/work the same way? I can kinda see the possibility, if, lets say, at the factory, one fork was assembled sepparate from the other, or one has a little more oil in it. These guys have experience with ducati's, one is acctually obsessed with them (like all of us, I guess), so they should know what they're tralking about.
Anyways, I'm going to call the shop manager to make sure, and I guess I'll call my dealer to cover all the angles. This is getting weird.
 

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Discussion Starter #12
Spoke to the head mechanic at the shop, and I'm taking it in tomorrow again. He's going to look at it, and I'll take it from there. He didn't give me a complete staight answer, 'cause he hasn't worked on the bike himself, but he told me not to touch anything.
 
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Duque does the shop you are going to have a fork dyno?
Curious to know how they ascertain an uneven preload
recommendation.

Nick how are you crunching zip ties if not bottoming out?
 

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Good question, Retro. I haven't actually crunched the seal on a zip-tie. When I had my forks apart for the Gold Valve install, I checked what things looked like at full bottom-out.
 

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I don't remember by how much but the internal travel bottom is higher than the external on the fork leg. So bottoming out will always leave some margin on the fork leg. Only when taking the rebound adjuster off it's possible to push all the way down.
 

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Just to clarify, I did the bottom-out position checking with the fork legs assembled, but no springs. The fork slider tube(which is attached to the wheel) bottoms out on the fork cap.
IIRC, it leaves about 3/16" gap between the seal and the fork lower (that holds the axle and caliper).
 

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Don, can I ask you what your weight is, and how you like the .9 springs? If you have the preload minimized, does that mean that if you loose weight, you have to get new softer springs again, or do you have enough room to play?
Thanks

Sorry, I've been off the board a while.

I have no room to back off preload. I have lost weight since the install last fall (and I'm trying to lose a little more). I was a bit disturbed at first about the setting I ended up with. The RaceTech website calculator had recommended .85 kg/mm rather than .9. But the shop didn't believe my stated weight. They weighed me and abused me and chose the .9s.

Having said that though, we did the setup with me in nylon pants, t-shirt and sandals. If you add leather, gloves, helmet, boots and a loaded tank bag, that's going to add up to more weight than I'm trying to lose (15 lbs) so there's really nothing to sweat.

For a track day, you lose the tank bag, but generally want to run stiffer anyway.

So it's a tough call. Ideally, you want to have adjustment to go either way for fine tuning, but if you don't need to back off, minimum preload is good 'cause it gives you maximum travel.

Oh yeah, last thing: I weighed 190 last fall when I had the springs swapped. I'm at 180 now and really happy with the front end. I'm sure another 5 lbs won't screw things up ;D
 

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Duque does the shop you are going to have a fork dyno?
Curious to know how they ascertain an uneven preload
recommendation.

Nick how are you crunching zip ties if not bottoming out?
What he said.

Sure it's possible that both springs aren't identical and consequently you'd want different settings, but no one measures that. Everything is set up symmetrically. So either your shop is loco or they're way ahead of our shops!

The fork tubes are coupled through the axle, so unless the springs and/or dampers are WAY different, they'll play nice together and it doesn't really matter.

I've never heard of anyone running different preload OR damping settings. The message has always been to adjust symmetrically.
 
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