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Discussion Starter #1
I apologize if this was answered somewhere else but I couldn't find it through searching.

A couple months back I had a really slow low side on a right hander. Frame sliders took the brunt of it. But my right rearset got bent, rear reservoir snapped off (which means I had to get a new subframe... ugh), and the front forks got a little tweaked.

After the crash the steering felt off, less stable, but I figured it was because the forks were slightly misaligned. I just got the forks rebuilt and realigned last week, and although they're straight the feeling is still there. At slow speeds it just feels so much more easy to tip left and right. When I used to take corners I'd tip it in and it would just feel like it fell into a line nice and smoothly. It still falls into the turn but it doesn't hold the line the same. If I brake with any lean I can feel it trying to pull the handle bars towards the lean much more than I've felt before. And overall just feels like it's floating more, not getting the feedback I'm used to.

At first I thought maybe they inflated my tires more, but no, same PSI. The only other things I can think of is that the suspension may be set a bit stiffer now, would that have this effect? Or lastly, can the steering damper get disabled after a tumble? Maybe my steering damper stopped working, that would explain a lot about why the steering feels so loose now.

tl;dr
I had a low side, my steering feels loose and less stable now, could that be from a stiffer suspension or a disabled steering damper?

Thanks in advance if anyone has any thoughts!
 

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What year is your bike?

If you have an 07 or higher here's what I would suggest to troubleshoot:

-Faulty HESD
-Damaged or loose steering head bearings
-Bent axle or frame
-Worn or damaged wheel bearings
-Worn or damaged swing-arm pivot bearings
-Bent steering stem

Just some suggestions. Good luck
 

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Discussion Starter #3
What year is your bike?

If you have an 07 or higher here's what I would suggest to troubleshoot:

-Faulty HESD
-Damaged or loose steering head bearings
-Bent axle or frame
-Worn or damaged wheel bearings
-Worn or damaged swing-arm pivot bearings
-Bent steering stem

Just some suggestions. Good luck
Thanks for the suggestions! It's a 2011.

Guess I'll have to take it back to the shop then. Hoping its simply a faulty HESD and not anything bent.
 

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Thanks for the suggestions! It's a 2011.

Guess I'll have to take it back to the shop then. Hoping its simply a faulty HESD and not anything bent.
Yup, if you're not the handiest that'll prob be your best bet. Just make sure to note that they left you with another issue after they worked on it. Just try to gain some leverage so they don't kill you on the pricing for another diagnosis--considering they could have done a faulty job...
 

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[...]After the crash the steering felt off, less stable, but I figured it was because the forks were slightly misaligned. I just got the forks rebuilt and realigned last week, and although they're straight the feeling is still there. At slow speeds it just feels so much more easy to tip left and right. When I used to take corners I'd tip it in and it would just feel like it fell into a line nice and smoothly. It still falls into the turn but it doesn't hold the line the same. If I brake with any lean I can feel it trying to pull the handle bars towards the lean much more than I've felt before. And overall just feels like it's floating more, not getting the feedback I'm used to.[...]
To some extent this sounds like a good problem to have.. one way or another you seem to have more front grip, meaning you can turn-in later and get back on the gas earlier. It's a characteristic I'd been trying to tune into my 600RR for a while.. coming from a Ninja 300 that had fantastic steering response. For a while I ran with the HESD disconnected, but the minor improvement wasn't worth the head shake on hard corner exits. I also replaced the rear shock with a Penske and revalved the front end with GP Suspension's 20mm kit. And with some amount of fiddling it added up to a responsive and confidence-inspiring ride. The last thing I tweaked seemed to make the biggest difference---as these things go---and that was adjusting the geometry.. raising the rear end with the Penske's ride height/length adjuster, and lowering the front end by raising the tubes in the triples.

What's interesting, though.. I recently swapped my forks with a pair equipped with GP's 25mm cartridges, and they must have more minimum installed preload because the front end sits about 5 mm higher now. But here's the thing: between the stiffer damping and the improved mechanical grip this setup steers even faster.. in spite of "stabilizing" my geometry. I'm thinking now I may lower both ends of the bike closer to stock height.. that or I need to extend the kickstand.

Anyway, if your fork oil was worn out, a rebuild can and should noticeably improve your front grip. If it was behaving differently turning left vs turning right then I'd agree something is wrong. But otherwise it could just be a matter of adapting your riding technique.. i.e. turn in later, use more throttle earlier.

If you can't (or won't) compensate and get accustomed to the new feel/feedback, you do have some ability to adjust the geometry even with the stock setup. Decreasing preload on the rear and/or increasing preload on the front will let the rear squat further and make the bike steer more smoothly and feel more stable mid-corner. [Do you know what your sag/preload settings were before?] The damping adjusters can also affect dynamic geometry. If rebound is too slow/compression is too fast that end of the bike will suck down into the stroke as you roll down the road. Conversely, if compression is too slow/rebound is too fast it will dynamically jack up that end of the bike. An experienced suspension tuner (which I am not) could identify this by simply pushing on your bike and observing how it responds. I would suggest you reach out to the tuners in your area, e.g. Catalyst Reaction, Super Plush.

There are a couple things you can check on your own, though.. assuming you have the tools. Check your front and rear suspension adjusters to see if they match the stock settings in the manual. [And feel free to explore the full range of adjustment. You can't go dangerously wrong with the stock adjusters.] At slow speeds the HESD is designed to have little damping effect, but it couldn't hurt to check it. There's a test procedure, here: http://www.600rr.net/vb/35-maintenance/97101-hesd-function-test-procedure-07-08-a.html You do need to safely lift the front tire off the ground, though. A rear swingarm stand and a hydraulic jack under the headers works.
 

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Discussion Starter #8
To some extent this sounds like a good problem to have.. one way or another you seem to have more front grip, meaning you can turn-in later and get back on the gas earlier. It's a characteristic I'd been trying to tune into my 600RR for a while.. coming from a Ninja 300 that had fantastic steering response. For a while I ran with the HESD disconnected, but the minor improvement wasn't worth the head shake on hard corner exits. I also replaced the rear shock with a Penske and revalved the front end with GP Suspension's 20mm kit. And with some amount of fiddling it added up to a responsive and confidence-inspiring ride. The last thing I tweaked seemed to make the biggest difference---as these things go---and that was adjusting the geometry.. raising the rear end with the Penske's ride height/length adjuster, and lowering the front end by raising the tubes in the triples.

What's interesting, though.. I recently swapped my forks with a pair equipped with GP's 25mm cartridges, and they must have more minimum installed preload because the front end sits about 5 mm higher now. But here's the thing: between the stiffer damping and the improved mechanical grip this setup steers even faster.. in spite of "stabilizing" my geometry. I'm thinking now I may lower both ends of the bike closer to stock height.. that or I need to extend the kickstand.

Anyway, if your fork oil was worn out, a rebuild can and should noticeably improve your front grip. If it was behaving differently turning left vs turning right then I'd agree something is wrong. But otherwise it could just be a matter of adapting your riding technique.. i.e. turn in later, use more throttle earlier.

If you can't (or won't) compensate and get accustomed to the new feel/feedback, you do have some ability to adjust the geometry even with the stock setup. Decreasing preload on the rear and/or increasing preload on the front will let the rear squat further and make the bike steer more smoothly and feel more stable mid-corner. [Do you know what your sag/preload settings were before?] The damping adjusters can also affect dynamic geometry. If rebound is too slow/compression is too fast that end of the bike will suck down into the stroke as you roll down the road. Conversely, if compression is too slow/rebound is too fast it will dynamically jack up that end of the bike. An experienced suspension tuner (which I am not) could identify this by simply pushing on your bike and observing how it responds. I would suggest you reach out to the tuners in your area, e.g. Catalyst Reaction, Super Plush.

There are a couple things you can check on your own, though.. assuming you have the tools. Check your front and rear suspension adjusters to see if they match the stock settings in the manual. [And feel free to explore the full range of adjustment. You can't go dangerously wrong with the stock adjusters.] At slow speeds the HESD is designed to have little damping effect, but it couldn't hurt to check it. There's a test procedure, here: http://www.600rr.net/vb/35-maintenance/97101-hesd-function-test-procedure-07-08-a.html You do need to safely lift the front tire off the ground, though. A rear swingarm stand and a hydraulic jack under the headers works.
This is great information, and glad to know it's not necessarily a bad thing, that it could be a step in the right direction in some regards. I will check the things that I can and ask about the other things when I bring it into the shop again. At least this gives me some more informed questions to ask. I plan on hitting up catalyst reaction for my suspension in general, it's just that they were booked pretty far out, so I hadn't been able to get there yet. Interesting to know the suspension can make that big of a difference too though.

when you reinstalled the forks did you put them at the same height in the triple as they were from stock?
I'm not sure, I had a shop do it for me. Not sure how to check this but I'm sure a quick search in the forums will tell me. Thanks for the tip!
 

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if the forks are set higher in the triples it'll make the bike steer faster.

some find it uneasy feeling, but that's my preference
 

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Discussion Starter #10
That's really good to know, I'll check that out, thank you! Are there marks on the forks to reference or is it a measurement from a set point type of thing?
 

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there are lines on the forks. i can't recall where they go stock.

if the guys didn't install the retaining rings for the clip ons then it's possible they are set too high. if the rings are still there then it's pretty well impossible.
 

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Here's mine at 5mm below stock, i.e. front end lowered 5mm. There are lines at this and the stock position.



The GP extended fork caps would allow me raise the front end as much as 16mm vs stock, which probably makes more sense on a different chassis.

The fork tube diameter tapers inward about 5mm below the lower triple clamp, so presumably I could go another 5mm lower than my current position. At some point you have to worry about the fender hitting the radiator, though.
 

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Discussion Starter #13
Awesome, thanks for the photo reference. So did lowering it 5mm make a noticeable difference in handling? Based on what wibbly is saying it sounds like that would make the steering feel a bit more centered and a little harder to flick?
 

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Very noticeable, yes.. but opposite of what you said. More weight on the front tire makes it easier to turn. At the expense of mid-corner stability. But that's not been an issue so far with my riding style.

Expert riders will carry more brake pressure into the corner (i.e. heavier trail braking).. dynamically steepening the geometry to help the bike turn. And therefore choose a more balanced static geometry for better mid-corner feel. I've only really gotten into trail braking this year but I can already see the potential.
 
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