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Old 09-16-2013, 12:17 PM   #1
stoke OP
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The Dark Arts Of Centerstand Grinding Management. Pic & A Question

So I just installed an SW Motech centerstand on my 2008 DL650 Vstrom. On my third ride out with it this morning, I took my usual commute that includes a left hander I usually hit low and hard. It has a dip in it.

This morning just when I was leaned all the way over with shocks compressed, I hit that dip and there was quite the grinding noise and bit of shock to the bike, nothing crazy though. I never had any problems before, sometimes my peg and boot would scrape but that's it.

Here's the pic, with three green arrows to point out the grinding:

 photo centerstandgreenarrow_zps02e75537.jpg

My question for all you seasoned vets out there:

How big of a deal is this?

Should I worry about it? I didn't touch the peg or boot down this time. Definitely surprised me though.

I was thankful that the stand kept the square thing you stand on to lift the bike up off the pavement. Back in my Honda Reflex days I was almost in a wreck from dragging that once. Thing was like an anchor in the pavement. Never did it again on that scoot and it's one of the reasons I transitioned to a motorcycle over a year ago.

Looking forward to your answers. For some reason, after 14 months, 12,000+ miles and five rider training courses, I seem to be leaning the bike over and touching boot or peg down regularly. Wondering how much I should be concerned about the centerstand dragging.

Thanks,

Stoke
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Old 09-16-2013, 12:33 PM   #2
flying_junk
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I think that it's a safety issue. Here is my physics based opinion on it.

any amount of force that is used to grind the stand, or that the stand absorbs while impacting the pavement in the turn, is that much less traction on your tires.

so, if you are hard in a corner, and you are at 90% traction, if the impact of the stand hitting the ground in the corner absorbs more than 10% of the force while you are cornering, you will loose traction and slide out. I think it's quite dangerous, and depending on dips, and other unpredictable factors on the unevenness of the pavement, can easily cause you to slide out.
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Old 09-16-2013, 12:35 PM   #3
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Cool2

Quote:
Originally Posted by stoke View Post
How big of a deal is this?

Should I worry about it? I didn't touch the peg or boot down this time. Definitely surprised me though.
The pegs should drag first, so you can feel it with your feet.
Dragging hard parts on the street is bad for two reasons:
1) You should not be going so fast as to lean above 35 degrees.
2) The dragging point becomes a pivot point on which one of the tires can be lifted enough to lose all traction and induce a slide and low-side fall.

In order to avoid all that without removing the new stand, try leaning your body more than the bike and accelerate early and during the turn, so the suspension lifts the whole bike up giving it more ground clearance.
If you can play with pre-loading at both ends, more of it will make the bike squat less during turns.
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Old 09-16-2013, 12:37 PM   #4
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Read up on, and check suspension sag.

It could be more preload cranked in will be all you need, or, a higher rate spring may be required.

Check both front and rear suspension sag measurements. With rider weight on the bike it should sag 25% - 35% of total travel. If your sag measurement is greater than that it could explain what happened.

(for example, a bike with 6" of travel should compress no more than about 2" when sitting level, loaded with rider and gear.)

If you are under sprung for the load you may be bottoming inadvertently, or at least going further into travel than optimal.
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MotoTex screwed with this post 09-16-2013 at 12:43 PM
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Old 09-16-2013, 12:49 PM   #5
rocker59
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1) hang off more
2) stiffer suspension

problem solved.
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Old 09-16-2013, 01:03 PM   #6
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Quote:
Originally Posted by rocker59 View Post
1) hang off more
2) stiffer suspension

problem solved.
I can't believe I'm saying this out loud... but you could slow down a bit, if it really bothers you.

I'd get the grinder out and add clearance though
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Old 09-16-2013, 01:43 PM   #7
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Excellent advice from everyone that mostly confirms what I was thinking: hang off the bike more with my body to reduce the bike's lean angle, adjust the preload and have better throttle control.

I always follow the Slow, Look, Lean, Roll (on the throttle) when cornering, but now that I think about this one again, I wasn't rolling on the throttle as much as I should of been during this turn to stand the bike up on it's suspension to counteract the downforce. I was more or less just maintaining the throttle.

And in response to this:

Quote:
I can't believe I'm saying this out loud... but you could slow down a bit, if it really bothers you.
I'm not zooming around all over the place taking undue risks, but dammit, those fast corners just feel really good and I always use this particular one to practice. I look forward to it on the way to and from work every day. It doesn't bother me terribly, just want to learn the proper way to manage/ prevent it the next time.
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Old 09-16-2013, 02:39 PM   #8
rocker59
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My Guzzi Quota would bang the centerstand in mid-corner dips.

It had a nice, plush, long travel suspension that was great on rough roads.

Eventually, it quit dragging (mostly), after I bevelled it off real good!


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Old 09-17-2013, 10:11 AM   #9
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So I took the exact same corner this morning

At almost the same speed, though not quite as fast. Same line. Had already adjusted the preload last night, was hanging off the bike much more and rolled the throttle on during the arc vs just maintaining it.

No bang and grinding this time, plenty of clearance. I will say, that bump is at the worst part of the turn, right when you're leaned over the most-no wonder the hard parts hit. I consider myself lucky that like someone said on this thread, it didn't lever the back wheel up off the pavement.

All said and done, I'm going to take some track style courses this winter up in LA. Not sure which ones yet, going to do it though. I need to get better at cornering.
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Old 09-17-2013, 10:55 AM   #10
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If you are grinding hard parts off while street riding, you aren't leaving yourself much of a safety factor (like having to adjust your line slightly tighter due to some sudden obstacle)

As you mentioned, track days are a much better place to probe the limits of you and the MC.
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Old 09-17-2013, 10:58 AM   #11
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Quote:
Originally Posted by DC2wheels View Post
If you are grinding hard parts off while street riding, you aren't leaving yourself much of a safety factor (like having to adjust your line slightly tighter due to some sudden obstacle)

As you mentioned, track days are a much better place to probe the limits of you and the MC.
You got that right. I definitely didn't need my coffee as much yesterday morning.
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Old 09-17-2013, 08:14 PM   #12
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Dragging anything on the ground that doesn't move is a bad thing. I'd loose the center stand. You don't need it anyway. Back in the day when the majority of bikes came with them it was the first thing I took of a bike when I bought a new one.
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Old 09-17-2013, 08:47 PM   #13
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Quote:
Originally Posted by Homey View Post
Dragging anything on the ground that doesn't move is a bad thing. I'd loose the center stand. You don't need it anyway. Back in the day when the majority of bikes came with them it was the first thing I took of a bike when I bought a new one.
Agree. Front and rear stands FTW.
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Old 09-17-2013, 09:56 PM   #14
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Don't worry about it, you're just fine tuning the new centerstand.
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Old 09-18-2013, 06:58 AM   #15
MotoTex
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Quote:
Originally Posted by Barry View Post
Agree. Front and rear stands FTW.
They are just so difficult to carry along for the middle-of-nowhere tube change or repair.

This is an ADV thread .... not always the same scenarios as those weekend warriors who rarely venture far from home and easily have their buddy help them trailer back to those Front and Rear stands in the comfy garage.

My wife's Monster 696 annoys me greatly because of the absence of a center stand, or even the ability to fit one. She bought it because it was the only bike she liked that fit her inseam and wasn't a cruiser. Makes chain maintenance on a trip quite a chore. I hope she never has a flat on a trip, we'd have to abandon the bike or call for a tow.
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