Not sure how to explain this. 

Maybe it's because I'm new, but my bike feels wiggly around turns.  The rear end seems to do it's own thing sometimes.  It's not exactly slipping, more like shifting an inch or so toward the outside every now and then. 
The tire's new, but broken in.  The axle assembly is assembled correctly.  I didn't use a long straight edge to find alignment, I just measured the chain adjustment studs.  Is that the problem, or am I hitting gravel or something? 
I'm not leaning too far.  I've still got 1/2" chicken strips on both sides. 
I find myself losing commitment to some corners out of fear that it's gonna slip. 

Do I just need more speed for that lean angle?  Bike feels like it's not really "planting", but what do I know.    
Geez, I need track time...



Oh, stock besides progressives up front.  I'll post the tire brand if it's necessary. 
I don't ride on wet roads, so that's not the problem. 

The prerequisite dumb question must be asked...Did you check your tire pressure?  Next question would be on what setting is your rear shock.

Whats your suspension setup like?  Another thing is your tires.  It could be if they are squared off, you're just falling off the edge from the center flat to the edge.  However, seeing as you say they're new, are they the proper size for the rim or are they to big?  If they're too big, they may be pinched and could be falling off the high center to the edge.  My best educated guess be the suspension.  Stiffen up the front, stiffen the pre-load or replace the stock rear shock.  I used to have the same feeling, but when I put the Race Tech springs and heavier oil in the forks and stiffened the preload to 7 (I`m 5`11 250lbs for now), alot of the squirreliness went way, but I still have some that I`m working on.

Quote from: Infinite Dimentia on March 17, 2009, 09:17:14 PM
Whats your suspension setup like?  Another thing is your tires.  It could be if they are squared off, you're just falling off the edge from the center flat to the edge.  However, seeing as you say they're new, are they the proper size for the rim or are they to big?  If they're too big, they may be pinched and could be falling off the high center to the edge.  My best educated guess be the suspension.  Stiffen up the front, stiffen the pre-load or replace the stock rear shock.  I used to have the same feeling, but when I put the Race Tech springs and heavier oil in the forks and stiffened the preload to 7 (I`m 5`11 250lbs for now), alot of the squirreliness went way, but I still have some that I`m working on.

I'm noticing some wiggle myself now too... I have a Kat rear shock and .90 sonics with 15w in the front. I've tried softening the comp damping, and stiffening the rebound, vice-a-versa, and adding a tad bit of pre-load... but it's hard to determine if it's acting odd because it's too hard, or too soft. On hard bumps or dips the ass end likes to throw me off the seat a bit... but the preload front and rear are set to my weight for sag... 32mm.

So I dunno what's up. I'm also running 150's on the rear, but they're a smooth transition from center to sidewall, so I wouldn't figure that's the case.

Weird. If you guys figure something out post your findings, and I'll do the same on my end.

If your rear tire is squared off from highway miles, transitioning though the ridge between the normal tire profile and the flat zone will cause a squirrelly feeling in corners.

Low tire pressure, hard tires, and out of alignment wheels and loose steering head or swingarm bearings can cause a wiggle too.

Being a new rider, it is likely you're not looking though the corner.  Stop staring at your front wheel and keep a light grip.

Yeah, everything GeeP said. When my bike starts to feel like it is stepping out in corners, it is always the tire pressure being a bit low. A few pounds low is more than enough to notice....

Thanks, Danny.  
Do you have drag bars, 89's, stock, or what?  I'm trying to rule out unconsciously overcompensated steering input, perhaps exacerbated by wider bars.  
I know it's a long shot...

What's the experience on your bike?  I get a very abrupt shift to the outside for about an inch or two, with no noticeable friction between tire and road.  No change in speed or RPM, just a slide to the outside.  
I'm also the opposite of a 250-lb fat-ass.  How about you?  





The rest of you can go away.  
I've lost patience for narcissists.  

Radial or bias-ply tires? I think bias ply tires are more likely to do this.

I remember on my GSX-R the radial tires had a very linear and solid grip. Once it was at a certain angle it would stay there without any input. My GS is also squirrely through corners, don't feel at committed at hard lean. May just be your tires.

yeah tar brand might be good info and tire pressure.

Another thing to check would be wheel alignment. After my gsxr and bandit wheel swap I had a little wiggle and slip on turns. After properly aligning the rear wheel it went away.

Avon Roadrider 130/70-17, pressure's at around 38.  
Barracuda 110/70-17, pressure's at 36.  Set by the dealership when I went in for inspection about 2 1/2 weeks ago, and still correct this morning.

Most of the sliding is happening at or past about 20 degrees from vertical, I'd say.  Not exact measurement, of course, but I'm trying to say that I have to lean it somewhat to induce the slipping.  
I just got the rear around December or so, and I've put about 800 miles (max) on the it.  The front came with the bike, but it looks fine.  No dry-rot, lots of life left before the wear mark, no bulges, cuts or grooves, etc.  
All the bearings in the entire bike are new, as are the sprockets, chain, rotors, etc.  It's a rebuilt bike.  Axle assembly is in correct order and verified by dealership mechanic, everything's torqued to factory specs with blue loctite.  New bolts and hardware where possible.  

Brand new progressives up front, with 3/4" PVC spacer.  Stock rear shock set pretty soft (maybe 2 or 3 up from lowest setting).  I'm not a large person, so it's pretty necessary.  No lowering, everything is stock.  It just likes to do it's own thing around corners sometimes.  It's like it decides to take a little trip to the outside for some reason.  




I had a steering neck bearing issue that I thought was the problem.  But, I cleared that up by checking the assembly hardware.  I've verified that with the dealership mechanic, also.  He says it's "A-ok".  He doesn't have a clue about the tire slippage, though.  He wants to take it for a test ride to find out...  




Like I said, I used the measurement method to obtain alignment.  That method's been verified by many members on this board, so either it's wrong or my alignment is fine.  
Measured the chain adjustment studs on either sides and center of axle. 

I think everyone here hit all of the likely reasons.  Are you sure it's not normal.  The reason I say this is that with a too soft rear (compared to the front) is going to use alot of travel. 

Think about if a bike is vertical.  When you push down while the bike is upright all of the suspension travel is vertical.  As you lean you get a horizontal component to it.  If you lay the bike on its side and compressed the suspesion you would get 4 inches of horizontal travel and no vertical travel.  So... if the bike was at a 45 degree angle, you might have 2 inches of vertical travel and the same amount of of horizontal travel.  You don't really notice this with the correct spring rate since there isn't that much travel during most riding, but if you are undersprung (stock shock) you might feel this. 

I feel it everytime I take an onramp too fast with my wife on the back of the busa, and noticed it too on the GS before swapping shocks.  I'm guessing this is what is going on because if it was actually sliding that bad you probably would have crashed by now!!  Just a thought. 

That's why I was annoyed.  I've gone over those things myself before posting (and giving fodder to all the hungry critics). 
The things I don't know yet are the effects of the rear shock, like you mentioned, and whether my rear tire compound is too stiff.  I have tried to narrow it down to that, because I can feel it in the seat of my pants as the entire rear of the bike is swinging.  It's not so much a rear swing-arm movement as it is the entire rear of the bike.  That's why I bit the bullet and posted on here. 

My other annoyance would be from conceitedly posting all of one's upgrades and trying to give advice, while admitting that the problem still exists on his own bike. 
Or, telling me to look through my turns. 


I have no idea whether it's normal or not.  I appreciate your response.  But, I ask you the same question.  Is it normal? 
I have already lowsided from this. 

Quote from: wladziu on March 18, 2009, 12:53:07 PM
I have no idea whether it's normal or not.  I appreciate your response.  But, I ask you the same question.  Is it normal? 
I have already lowsided from this. 

Anything that makes you lowside needs to be fixed immediately.  Anything that makes you hightside requires you take a life insurance policy out with me as a beneficiary.

If it feels like it's the whole back end, I'm going with tires.

Ignoring the lack of dry rot, how old are your tires, even if "new"?  There's an open issue in the tire world about tire aging and oxidation, and how the compounds change, blah blah.  While I'm asking, you said you'd checked inflation, and tread, right?  Did you use the numbers on the frame or on the tire, btw?  I'm not going to advise you do do this, but I've heard of people taking 2-3 psi out of the rear tire to deal with fishtail.

I'm racking my brain to try and figure out what you're feeling that doesn't include riding someone elses bike.  Anyway, here's what I came up with....

First off, do what lawman said.  Those could definately contribute.  I really doubt the possibility you mentioned in your previous post that your rear tire compound is too hard (unless it is old like lawman said).  A roadrider is a quality tire and more than capable of quite a bit of lean.  Everyone b*****s about bias ply tires and wants to blame them, but you'd be surprised how much grip you can get out of them.   I've scraped plenty of pegs and dragged a knee more than once at the track on a ninja 250 with bias ply tires.  

You'd really only notice the effects of the rear shock if your choice of spring was way off base.  Since you've exhausted pretty much everything else, there is one more way to see if you have the correct spring rate.  You can do this by setting your race/static sag the recommended way (if you haven't already).   Racetech has a great writeup on this.  I say this because setting race/static sag correctly will give you another number to measure.  

That number is free sag and it is important.  It tells you if you are undersprung or oversprung.  

Free sag is how much the bike sags with you off of it.  The ideal number is 0-5mm.  If you end up with zero, that's not necessarily bad, as long as the bike doesn't top out hard.  It should just kind of settle there.  If you are in this range after setting preload the spring rate is appropriate for your weight.  If not than you are using preload (too much or too little) to compensate for the wrong spring rate.  This would tell you if your shock is appropriate for your weight.  

Anyway following these directions will tell you definitively if you have both the correct spring rate and preload in the rear.  If you do, than that probably narrows out excess travel as what you are feeling.


http://www.racetech.com/SubMenu.asp?cMenu=4&c=Yes&cSubMenu=11&showPage=street#3

That's about all I can come up with.

Quote from: wladziu on March 18, 2009, 12:53:07 PM
That's why I was annoyed.  I've gone over those things myself before posting (and giving fodder to all the hungry critics). 
That's why I bit the bullet and posted on here. 
My other annoyance would be from conceitedly posting all of one's upgrades and trying to give advice, while admitting that the problem still exists on his own bike. 
Or, telling me to look through my turns. 

These people are only trying to help you by telling you what worked and didn't work for them. No one has said anything conceited or out of line. You my friend need to take a deep breath and figure out if you want to solve your problem(if there is one) or cause more. If your acting like this towards this group of guys I pity you if you try to deal with many of the other turds you'll find on some forums. I can guarantee you that if you continue to take things the wrong way and look for trouble where there isn't any you'll soon find yourself wondering why no one wants to try to help you when you post your questions.

JoNathan

Props to Jonathan!  I second that motion!  This is one of the nicest groups of guys anywhere on the internet.  Take a pill and calm down!  We're only trying to help you, and free of charge I might add.

Always rule-out the simple things first.  First, are you mental?  Ok, that was a cheap shot, I'm sorry, but I couldn't resist.

Now for the serious stuff.  Even if you're light, crank the rear shock up to 4 at least.  2 and 3 are too soft, even for you.  4 is the factory setting for the stock shock, and that's soft.  I use 6 and I weigh 190.  Check your pressures, 33 front and 36-41 rear.  I know it's dumb, but I have to mention it.  Also, compare your rear axle chain adjustment marks and make sure they're at the same position.  As others have mentioned, if you have a lot of wear in the center of the back tar and none on the edges you're going to feel it when you lean significantly.  In that case I would suggest practicing at low speed in a big empty parking lot.

when i had my sportster i would wiggle when i leaned it over and goot on the lip of the tire from time to time.

Quote from: wladziu on March 18, 2009, 08:51:47 AM
Avon Roadrider 130/70-17, pressure's at around 38.  
Barracuda 110/70-17, pressure's at 36.  Set by the dealership when I went in for inspection about 2 1/2 weeks ago, and still correct this morning.

Most of the sliding is happening at or past about 20 degrees from vertical, I'd say.  Not exact measurement, of course, but I'm trying to say that I have to lean it somewhat to induce the slipping.  
I just got the rear around December or so, and I've put about 800 miles (max) on the it.  The front came with the bike, but it looks fine.  No dry-rot, lots of life left before the wear mark, no bulges, cuts or grooves, etc.  
All the bearings in the entire bike are new, as are the sprockets, chain, rotors, etc.  It's a rebuilt bike.  Axle assembly is in correct order and verified by dealership mechanic, everything's torqued to factory specs with blue loctite.  New bolts and hardware where possible.  

Brand new progressives up front, with 3/4" PVC spacer.  Stock rear shock set pretty soft (maybe 2 or 3 up from lowest setting).  I'm not a large person, so it's pretty necessary.  No lowering, everything is stock.  It just likes to do it's own thing around corners sometimes.  It's like it decides to take a little trip to the outside for some reason.  




I had a steering neck bearing issue that I thought was the problem.  But, I cleared that up by checking the assembly hardware.  I've verified that with the dealership mechanic, also.  He says it's "A-ok".  He doesn't have a clue about the tire slippage, though.  He wants to take it for a test ride to find out...  




Like I said, I used the measurement method to obtain alignment.  That method's been verified by many members on this board, so either it's wrong or my alignment is fine.  
Measured the chain adjustment studs on either sides and center of axle. 

well, that's not the right way to measure your misalignment. it's a ballpark. it assumes there is no slop in your swingarm, and that the dies at the factory never ever change, that everything was line-bored perfectly, with not problems whatsoever. i doubt that.

please see this thread: http://www.yamahafz1oa.com/sportryderswheelalignmentmethod.shtml
for a simple and dead on method to align your rear wheel to your front wheel.

a poor alignment plus a worn tire can cause all kinds of odd feelings in corners.

you mentioned a tire pressure of 38 psi, and 36 psi, iirc. -that's too high also. iirc the correct pressure with passenger for the rear is 36psi. if you're a lightweight kinda fella, 38psi and no passenger would make the rear slide around pretty easy.

have you tried averaging the readings on THREE pressure gauges ? some of them are complete shaZam!,  and read anything from 5-10 psi off per reading. try another.

you said you had a steering stem issue. that could be coming back again. could be a poorly installed bearing getting tight, loose in it's bore, etc. try another mechanic for a check-out ?

lots of things to check, and one possible thing... maybe you're riding above what your tires can handle ?

good luck matey, and no, no one on this board will act conceited or belittle you, unless you ask for it (from what I've seen)

Wow, a lot was said.. good stuff too. Thanks (also) for all your input on this.

What I'm experiencing may be due to a few things... I'm running Avon Roadriders as well, however I've got 150/70's on the back, so they're a tad taller...

They have about 300 miles on them and they were WELL broken in the first 100 w/ deep scrubbing in corners, zig-zags, and a fair amount of high speed.

I do have 1 inch "chicken strips" that I have yet to scrub out... so that MAY be why I feel a little wiggle or slight push out in the corner... but I think mine is more suspension based.

The bike seems to hop in slightly rough corners and I almost fear the rear end will bounce up and then sideways causing a low-side. The Katana 750 shock I'm running is set at the highest rebound damping, and 1 turn out on the compression damping with exactly 32mm of sag in the rear (perfect for my weight... 230lbs)...

I think I just have more suspension fiddling to do.

I have been looking through the corners when I'm really tucking in and I've been trying... TRYING to get a knee down here and there. I think all of the "new" maneuvers and testing and practice has left me on edge about even the slightest bump or hit and I'm still nervous about what the bike can or cant handle... only because I've just recently started driving it so... correctly? lol.

I'm running super-bike bars on my GS... so I have excellent control over the front end and need no damping or anything to keep things in line. Amazing leverage with those things and they keep my wrists at a more comfortable angle than the stockers.

I'm just gonna keep hit/missing things for a while till I see what works. I also have NOT checked my tire pressure... I just slapped them on after the shop mounted new tires... so I'll go and do that before I start testing things again.