Let's chat about chatter

[csmith12]

I aint talkin' bout chatter cheese neither.

Here is what I am experiencing when playing around in the A group on a stock front end. I am trying to get rid of the chatter from the front at apex and exit.

Link to original page on YouTube.

I am 192lbs fully gear'd up and have beside me some racetech .85 springs with emulators. Question is what weight oil. 5, 10 or 15? My preference is a stiff suspension feel. I got all winter to work this out, so I can swap different oils, change settings, springs whatever to get it right.

[tooblekain]

Originally Posted by csmith12

I aint talkin' bout chatter cheese neither.

Here is what I am experiencing when playing around in the A group on a stock front end. I am trying to get rid of the chatter from the front at apex and exit.

Link to original page on YouTube.

I am 192lbs fully gear'd up and have beside me some racetech .85 springs with emulators. Question is what weight oil. 5, 10 or 15? My preference is a stiff suspension feel. I got all winter to work this out, so I can swap different oils, change settings, springs whatever to get it right.

Fork Oil controls rebound. The higher the weight, the slower the rebound. What are your sag numbers? If they are off, you need to make sure you get the proper sag numbers.

You have emulators, but what are they set at? How many threads showing on the bolt? Do you have the blue spring on there or the yellow spring? Based on my experiences with chatter on the 250, it could be many things...too soft of a setting on the emulatr...too hard of a setting on the emulator...perceiving something as chatter but in reality is not (i.e.--you're actually feeling the suspension work a little, headshake caused by the front end getting a little light, a little moment where the front wheel lost contact with the pavement due to a bump/dip on the track, the front tire struggling for traction because you're really pushing the tire's traction limits so as to lose and regain traction frequently, braking too hard and bottoming out the forks, etc)

More often than not, the perceived chatter that many people feel is not actually true chatter. True chatter operates at a certain frequency. I'll see if I can find any of my videos that show real chatter.

Where I would start is looking at your emulator settings. What spring is on there? The blue spring or the yellow? How many thread in are showing on the bolt below? Once you find out our emulator settings, I would try loosening the first to maybe show 2-3 threads showing and go out and ride at 80% to see if that is better. If it is, push for max effort/same effort where you do get chatter. Did it solve the problem? Yes--then your done. No but it's better than before---then you're heading the right direction and maybe either loosen the emulator some more or tighten and it and repeat the steps until you get your desired set up. No, it got worst---then revert back to the original settings and maybe try tightening the emulator bolt some more. If you reach about 7-8 threads showing on the emulator bolt, you've maxed out the emulator and may need to go to the stiffer spring

[csmith12]

Thanks for the info.

Well... the parts are still in the boxes right now as my last race this year was last weekend and they didn't arrive in time for last weekend. The only thing left to buy is oil at this point. Once I get them installed I will be start measuring sag numbers and such.

[alex.s]

what tires? looks like you want some stiffer damping with softer tires.

[csmith12]

Rosso II's, I am already running about 5lb's less psi than everyone else in the field.

[alex.s]

maybe its time to step up to the slicks? are you strong-arming the front end? d-rapist was having chatter issues until he said he was manhandling the bars.

[tooblekain]

Originally Posted by csmith12

Rosso II's, I am already running about 5lb's less psi than everyone else in the field.

Rosso II front and rear?

I am running 2 sets of wheels. One with the Rosso II front and rear and the other is the Dunlop Unbeatens

Compared to the Rosso II setup versus the Rosso II rear with a Diablo Supercorsa SC2 front, the Rosso II doesnt stick as well as the the Supercorsa and what I felt as chatter was actually breaks in traction. I was able to run a fast lap time of 2:10.xx on Rosso II setup at Chuckwalla. I raced doing 2:11s. I had to make some line changes compared to the DOT front Rosso II rear setup I was use to to make it work.

If you're riding in the A Group and using Rosso IIs, you're pushing the tire's limits. You should be at least on a DOT front tire.

[alex.s]

Originally Posted by tooblekain

Rosso II front and rear?

I am running 2 sets of wheels. One with the Rosso II front and rear and the other is the Dunlop Unbeatens

Compared to the Rosso II setup versus the Rosso II rear with a Diablo Supercorsa SC2 front, the Rosso II doesnt stick as well as the the Supercorsa and what I felt as chatter was actually breaks in traction. I was able to run a fast lap time of 2:10.xx on Rosso II setup at Chuckwalla. I raced doing 2:11s. I had to make some line changes compared to the DOT front Rosso II rear setup I was use to to make it work.

If you're riding in the A Group and using Rosso IIs, you're pushing the tire's limits. You should be at least on a DOT front tire.

when my R2's were new i think they could have pulled 2:05s before real trouble... i was not sliding too bad at 2:11s. but its definitely getting close to that zone where you gotta be careful.

[csmith12]

Yes sir, Rosso II front and rear. I know the front is breaking traction already, that is part of it no doubt. When the bars want to turn inward on their own, your at the very edge of tucking the front due to traction loss. Been there, done that already. Otherwise bumps/camber changes or tight on the bars seem to start the whole chatter/traction mess or I overcook an apex a bit but ride it out anyway or just a crap stock front for what I am doing.

When I am not causing it, I am thinking damping or springs because other turns are butter smooth at steeper lean angles and faster speeds. Take my avatar for example, turning harder, leaned over more and going faster with no issues. And it happens every lap... we all know bikes don't do things every other lap or every third lap.

And your spot on about line changes. At Putnam, turn 2 has some wavy bumps just on the outside of the race line. If your barely off the race line with my setup, it don't feel good at all. A later apex keeps me out of the bumps and keeps the angry front at bay for that corner. And yea, the video is A group pace and normally about 2-4 seconds give or take back from lap record pace during races.

So now the plan is to get my parts installed
Set sag
Get an SC2 front
Tweak from there

[csmith12]

Originally Posted by alex.s

maybe its time to step up to the slicks? are you strong-arming the front end? d-rapist was having chatter issues until he said he was manhandling the bars.

Good thought, but definitely not. Check out the pic in the WERD thread (off-topic). Where it says WERD on the bottom of my lower. I keep very tidy feet, check the circle on the sole of my boot and a very light touch, hands just relaxed on the bars.

EDIT: Hmmm slicks, dunno

[tooblekain]

You saying your pace is actually 2-3 seconds slower than the current 250 lap record? If so, you NEED to at least go to a DOT front or race slick front.

My latest video I did where I ran the 2:08's I am 6+ seconds off the lap record set by Ari Henning. Now if Ari was running the Rosso II set up front and rear when he set the lap record at Chuckwalla, then I really need to pick his brain and see how he does it.

[csmith12]

What has me scratchin' my head is, the lap records we are talkin' bout were set with rosso II's both front and rear. But here is the kicker, they were set by lightweight riders. Darn little guys.

[tooblekain]

Originally Posted by csmith12

What has me scratchin' my head is, the lap records we are talkin' bout were set with rosso II's both front and rear. But here is the kicker, they were set by lightweight riders. Darn little guys.

And that could be why...lighter riders are putting less load on the tires.

Just because one setup works for a guy doesnt mean it will work for you.

[dino74]

Whats your fork height on the front end?

Whats the rear shock and its settings?

[csmith12]

Originally Posted by tooblekain

And that could be why...lighter riders are putting less load on the tires.

Just because one setup works for a guy doesnt mean it will work for you.

Of course not and ya know, I am not really chasing lap records. I just wanna go fast without getting the feeling like I gunna crash in every corner that isn't perfectly smooth. I ignore it and go on but it gets old after a while and makes it tough to improve pace while not getting good feedback from the bike.

@dino74 - The front is stock until I get these parts installed. I plan on starting at 20ishmm of fork above the triple because of my bones (made by rexbo) and a 08 gsxr shock. I can get you my current rear shock settings in the AM, they are in my garage somewhere. It's a mess with drywall going up for the fresh new look.

[KazMan]

Don't forget to record your fork oil amount (height from top of tube). A Motion Pro tool works pretty darn good for this. I am not running the stock amount of oil in the forks, slightly less so I can get them to loosen up a bit. Stock level was too stiff.

Also, you will want to get the preload caps as well.

[csmith12]

Will do Eric, thanks for the reminder about the caps. Note to self: order caps

Originally Posted by alex.s

what tires? looks like you want some stiffer damping with softer tires.

It took me a minute to put 2 n 2 together here. I think your on to something.

[bruce71198]

Maybe you should just slow down a bit !! Riding motorcyles that fast is dangerous !

[tooblekain]

Originally Posted by bruce71198

Maybe you should just slow down a bit !! Riding motorcyles that fast is dangerous !

My mom said that to me a lot of times....I ignored her. She still loves me (I think)

[csmith12]

Originally Posted by bruce71198

Maybe you should just slow down a bit !! Riding motorcyles that fast is dangerous !

Ummm.... hahahahahah he said slow. That is a 4 letter word to me.

[choneofakind]

Don't use the s-word! It makes the chris angry. You wouldn't like chris when he's angry.



That explains why he's never smiling. hmmmm

[bruce71198]

Originally Posted by tooblekain

My mom said that to me a lot of times....I ignored her. She still loves me (I think)

Lets not bring our mom's into this!!! AND dont ignore your mother!

[Dmented]

Emulator Valve Plate Bleed Holes 2 or four? what diameter hole?
Oil Level is good around 130mm using 15W.. i'm 195lbs and combine those numbers with relaxing on the bars and chatter drops. i was doing 2:08's on worn out bridgestone slicks... Oil viscosity should only really be used for tunin ya rebound damping. you need compression damping so i say adjust the Emulator Valve Spring Preload/pringng Stiffness or play with your holes... YOUR BLEED Holes. -_-

I hope i helped. lolz

[bruce71198]

I just read his original post again and it says he's got the ftock front end on it in the video and all the new pieces to put in but not in yet. Also I don't know why you guys think oil viscocity is only for rebound damping?

[Dmented]

I said should be used for that. sure EVERYTHING affects EVERYTHING. even the rear shock. but you can't just write words on here and expect it to fit everyone. the man asked for help/info. so i want to tell him to limit his adjustments when he DOES put the gear in... his chatter may be from a LOT of things. so for the record, I'm not a suspension guru... i don't practice and i'm only decent at a few tracks and on a few different bikes. so like i was just saying, the emulator does not affect rebound, oil viscosity does.

csmith12: did you see i gave you some of MY personal setting above? PM me if you need more details.

[alex.s]

Originally Posted by Dmented

I said should be used for that. sure EVERYTHING affects EVERYTHING. even the rear shock. but you can't just write words on here and expect it to fit everyone. the man asked for help/info. so i want to tell him to limit his adjustments when he DOES put the gear in... his chatter may be from a LOT of things. so for the record, I'm not a suspension guru... i don't practice and i'm only decent at a few tracks and on a few different bikes. so like i was just saying, the emulator does not affect rebound, oil viscosity does.

csmith12: did you see i gave you some of MY personal setting above? PM me if you need more details.

lol. i think Drapist got defensive!

we talkin about PRACTICE?!... practice. PRACTICE???

[Dmented]

Nah.. I'm just being a condescendingbitch... But i got real talk.

[csmith12]

And so it begins!

I am so late getting around to putting these parts on. If I can get the bike to give me good feedback, it's gunna be a good season.

I seen your settings Dmented. I will take them into account along with other info I have. I am no suspension guru either but do fairly well on my own adjusting it out in small increments. I also don't blindly trust someone else to dial in my settings without me knowing what was changed. I am OCD like that.

After re-watching a lot of last seasons video's. I think tooblekain was pretty close with the tire feedback vs true front end chatter, so the Rosso II's are coming off and slicks are going on. Not many racers here use slicks and not sure why, maybe it's more that what I need. But I don't care about the extra $$ as long as I don't end up on my head. It's bound to happen again as much as I temp fate. lol

[Dmented]

Originally Posted by csmith12

I seen your settings Dmented. I will take them into account along with other info I have.

After re-watching a lot of last seasons video's. I think tooblekain was pretty close with the tire feedback vs true front end chatter, so the Rosso II's are coming off and slicks are going on.

word and word..
good luck!

[alex.s]

so you've become "That Guy" that spends more money than everyone else just to go faster!

congratulations.

:P

[csmith12]

Lol, I guess, I didn't quite think about it like that.

[Nemesis]

Wonder why I don't get any chatter on any turn on any track I've been to.

I must be doing it Hong!

[alex.s]

it's cause you only weigh 20 lbs, hong

[Nemesis]

Originally Posted by alex.s

it's cause you only weigh 20 lbs, hong

Shoot...I wished I did. Talk about being light...you're a twig yourself.

[choneofakind]

lightweights? You got me beat? I'm at a nice 133-135. beat that.

[csmith12]

Chone, if you would do a good season or two of track days, you would be one fast mofo. You still need to feel the effects of chasing down a buddy and soon... soon... brah. Imma put you on my R6 and tail you so you can feel 150+mph.

[choneofakind]

Some day I'll get a full season in. It's just so pricey for me at this point. Once I have a stable job I'll get more into it. I've gotten kinda crazy on my MTB. I need to work on unleashing that in a safe way on the ninja

[csmith12]

Update time! The chatter is gone and I don't feel like imma crash on every corner anymore!!!!

On Monday, I bumped my pace up to near what would be closer to "race pace". It was a night and day difference in feedback from the front. I felt solid traction midcorner, yet forgiving where it needed it most, in the braking zone. The only issue now is the exit of really tight corners.

For example; @ Jennings, the exit of turn 8 at expert group pace would sometimes give me the feeling of tucking the front again. As of right now, Imma gunna write it off as the rider because it only was "sometimes" and bikes don't do stuff "sometimes". I can only explain it as a null feeling, no feeling of traction, no feeling of grip, no feeling of connection with working suspension. Not good, but not really bad either.

@alex.s feel free to give your opinion of the setup since you rode it for 2 days. Also, I only got a few step outs/skips from the rear on Monday. Turns 8 and 10 mainly, not sure why I didn't get as many as you did.

[alex.s]

your front end setup was amazing. i was able to do pretty much anything i wanted with the front. i think with my weight though the rear had just a bit too much damping. for some reason i'm really rough on the rear. i need to use more clutch.

[csmith12]

Originally Posted by alex.s

for some reason i'm really rough on the rear. i need to use more lube.

fixed!