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Old 09-25-2017, 09:17 AM   #16
afm199
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i dont understand why ud say this. motos can be setup to turn in adequately on the brakes. most fast riders have their bikes setup like this because theres tons of time to be gained by braking late and holding lots of brake pressure all the way to the apex. i cant imagine a scenario where a rider reports that the bike wont turn in on the brakes and their crew chief says "brake earlier & lighter".

Zammer is likely over-braking for every corner, leading to his lap time. that by itself should make it easier to get to the apex because hes going slower at turn in. its even possible that hes as close or closer to bottom at turn in compared to me. but of course, my bike turns in no matter how hard i brake cuz of its setup.
I think we both agree that "hard braking" tends to be upright braking, though there is certainly brisk braking during trail braking, it's nowhere near the magnitude of upright braking.

I can absolutely imagine a earlier and lighter scenario. It's not easier to get to the apex when you rush a corner and go in too deep. One of the checks that Ken Hill uses is missing apexes due to too much entry speed. Which happens a lot with rushing corners, going in too deep and braking too hard. I've heard Ken mention, many times, longer and lighter braking.

I've also ridden the same bike with just about the same suspension and it worked quite well. I think what is happening here is technique related, not so much suspension.
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Old 09-25-2017, 12:07 PM   #17
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I think we both agree that "hard braking" tends to be upright braking, though there is certainly brisk braking during trail braking, it's nowhere near the magnitude of upright braking.

I can absolutely imagine a earlier and lighter scenario. It's not easier to get to the apex when you rush a corner and go in too deep. One of the checks that Ken Hill uses is missing apexes due to too much entry speed. Which happens a lot with rushing corners, going in too deep and braking too hard. I've heard Ken mention, many times, longer and lighter braking.

I've also ridden the same bike with just about the same suspension and it worked quite well. I think what is happening here is technique related, not so much suspension.
there are some data plots floating around the internet that disagree w/ your first paragraph. decel is def maximized when straight up, but the diff btw that and even 30deg of lean arent what i would call "nowhere near the magnitude". ill try to find some that arent from GP. maybe i can find some in my own data too.

the thing i find funny about "rushing the corner" is that its all based on the rider's own skill level. the markers and speeds i use when i "rush" arent rushing the corner for MA race winners, just as Zammer's arent rushing the corner for me. im certain there is a rider skill problem here that is contributing to these feelings and the laptime - that's everyone. im just not gonna rule out setup problems because of that, esp given the info at hand. we should be able to work on both.

based on your comments here, im not surprised to hear u report that some comparable ride-height works. IMO, braking technique is the #1 reason that optimal setups can differ so much between riders. with your braking, your front end might be 10mm higher when u turn in for a given corner - which is about the magnitude of a change ive been suggesting in here.

fun convo, esp for filling the gaps until Zammer can try something.
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Old 09-27-2017, 02:59 PM   #18
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This has all been rather informative. I really appreciate the insight from both of you. I have two days out at Thunderhill in late October - I think what I"ll do is add a couple clicks of preload and raise the front end a bit (3-4mm sunk in the top triple) and see if I like how it feels better than current. If so then I'll try to pick up some fork cap extenders this winter.

If not, then I'll drop the front and test from there.
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Old 09-27-2017, 09:51 PM   #19
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This has all been rather informative. I really appreciate the insight from both of you. I have two days out at Thunderhill in late October - I think what I"ll do is add a couple clicks of preload and raise the front end a bit (3-4mm sunk in the top triple) and see if I like how it feels better than current. If so then I'll try to pick up some fork cap extenders this winter.

If not, then I'll drop the front and test from there.
That's actually not a bad idea. Raise it and see what happens. Or lower it and see what happens, either way it gives you more info.
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Old 09-28-2017, 09:21 AM   #20
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make sure u buy those forks w/ Ohlins carts and extenders in the For Sale section
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Old 09-28-2017, 09:31 AM   #21
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make sure u buy those forks w/ Ohlins carts and extenders in the For Sale section
Right? That's a screaming deal and that's a really good setup.
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Old 09-28-2017, 11:14 AM   #22
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Haha grad student budget + $350 into revalving the forks I have this spring = no more suspension budget. But I'm sure I'll regret it in a year when I have the money.

Though if I go with extenders then that's $200 plus install anyway...
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Old 10-01-2017, 10:12 AM   #23
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Haha grad student budget + $350 into revalving the forks I have this spring = no more suspension budget. But I'm sure I'll regret it in a year when I have the money.

Though if I go with extenders then that's $200 plus install anyway...
LOL. If you are riding with Keigwins this year, come by and say hello. I'll be glad to do some laps with you and give you some feedback.

I'm always pitted with the other instructors under the first canopy at Thill East.

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Old 10-02-2017, 09:32 AM   #24
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This is a little tangential, but I also feel like it's extremely difficult or nearly impossible to turn in if I'm braking beyond ~30%. Is that normal behavior, or do I need some suspension fixin'? Only shows up if I'm cooking a little hotter than I should on weekend rides (so yes, the non-moron answer is to slow down. I know).
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Old 10-02-2017, 10:27 AM   #25
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This is a little tangential, but I also feel like it's extremely difficult or nearly impossible to turn in if I'm braking beyond ~30%. Is that normal behavior, or do I need some suspension fixin'? Only shows up if I'm cooking a little hotter than I should on weekend rides (so yes, the non-moron answer is to slow down. I know).
30% braking on the street is not much. id expect a setup that i like to still turn with much more brake pressure.

normal behavior is an odd term. if u dont like something and u think its hold back your riding, id try to fix it. setup is always a compromise. on the track, ill often run a setup that is mediocre in one turn because its faster in 6 other turns. on the street, you are prob going to look for overall confidence and ease of riding. "near impossible to turn" doesnt seem like "ease of riding" to me. so ya, id def adjust something.

on the flip side, we can also adjust our riding to suit the setup. its hard to know when though. if the bike is heading for the dirt on corner exit, do u delay your roll-on point or do u add rear ride-height. more often than not, ill make an adjustment to see if i get something for free. if i add ride-height and dont lose any grip, it was a setup problem. if i do lose grip and go slower, i change it back and also change my riding.
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Old 10-02-2017, 11:02 AM   #26
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"my bike doesn't turn when trailbraking 30%"

before making changes to the bike i would make sure i'm not the one giving it bad inputs. am i weighting the inside arm? eyes where they should be?

it could feel like the bike isn't turning if my eyes are lingering on a braking marker or if my inside arm is stiff
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Old 10-04-2017, 11:02 AM   #27
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I rarely ride with Keigwins, but the next time I do I'll look you up. Thanks !

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Originally Posted by afm199 View Post
LOL. If you are riding with Keigwins this year, come by and say hello. I'll be glad to do some laps with you and give you some feedback.

I'm always pitted with the other instructors under the first canopy at Thill East.

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Old 10-26-2017, 10:48 PM   #28
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Alright, so some ride report info from my two days at thill this weekend:

I rode it with the forks sunk 4-5mm into the triple, felt horrible, couldn't turn for shit (like steering an outboard boat). Dropped it flush, little better, dropped another 2mm, felt better.

Ohlins guy at the track this time (Dan Kyle's dude Mike) and he said, drop the rear spring from a 105 to a 100, so we did. Now the sag is better (he suggested even lighter yet as there's no preload) but it's ~25mm rider sag now with that spring.

He also turned some dials and set the front a little faster on the comp so it would come down in a turn for me. It feels better than before for sure but it's still just slow as hell on turn in, to the point where I'm actually scared of missing the apex because it won't turn in fast enough - but have no issues with exit or running wide even when on the gas hard.

Are extenders the only answer? Raising the whole bike would help transition easier. I come in ragged now, when on that POS R6 I could run to the checkered every time without getting winded, and I'm a fit guy. I'm being light as I can on the bars and not locking out.

My laptimes are unchanged really. Still stuck 4-5 s out from my PR (now running 2:12's at thill east).

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Old 10-27-2017, 10:03 AM   #29
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why would u need extenders if u dont like the front end taller than flush?

if u think raising the whole bike would help, why didnt u leave the forks sunk in and add shock length?

did the tuner do anything w/ preload?

what track and which corners did the bike feel like a boat?

how much brake pressure were u holding to the apex? is there any correlation btw brake pressure and the boat feeling? ie did the bike turn in better on the brakes or no?
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Old 10-27-2017, 05:15 PM   #30
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Originally Posted by stangmx13 View Post
why would u need extenders if u dont like the front end taller than flush?

if u think raising the whole bike would help, why didnt u leave the forks sunk in and add shock length?

did the tuner do anything w/ preload?

what track and which corners did the bike feel like a boat?

how much brake pressure were u holding to the apex? is there any correlation btw brake pressure and the boat feeling? ie did the bike turn in better on the brakes or no?
In order:

- I was implying raising the whole bike, not just the front - I was under the impression this would make the bike transition easier from side to side

- I couldn't adjust the rear ride height because I don't have two of those super thin 24mm wrenches. So I dropped the front instead, since my goal this weekend was to experiment - how else am I going to find out what's wrong?

- I went to 4 turns (of 14) from full out on the front. Tuner backed it off to 2 turns. Felt fine, not bottoming (zip tie about 3/4cm from bottom of stanchion).

Rear has no preload. Tuner claims its still way too stiff, and it needs more sag. I can't remember the number he gave me but it was apparently less than ideal, he said that might be screwing with the whole bike. It sort of chops at high lean angles and he said that's why. Racetech and the GSXR forums seem to say 100 N rear spring is pretty close to spot on but he would rather back it off to a 95.

- Thill East. Mostly turn 1 and 8 I felt it the most that it was boaty. It wasn't unrideable but it was really hard to turn in and vague.

- I played with it, it felt better with more brakes to the apex for sure now with less compression in the front it was better. I think one leg was all the way closed (!) so that probably explains why it wouldn't pack down for me on the brakes previously.

If you wanted some reading, there's a great thread from an AMA racer here that outlines his and east coast suspension guru Thermosman's experimentation on this bike's setup.

Edit: the tuner's sheet he just emailed me said the rear sag was 20mm. I will try to remeasure myself because every resource I've found online says that this is the right spring for my weight.

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