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Title: Back Wheel Steppin Out Post by: carraway on May 28, 2009, 08:49:08 PM Hi
I posted in the general forum on this issue but I think my concern should have been posted here...so here goes. Just moved from an S2R 800 to the 1100. In a corner felt the back wheel steppin out. This is the first time this has happend to me and it scared the #$%^ out of me. People wiser than me have suggested that I might have been using too much throttle in the corner. Is this the likely explanation? Are there other explanations. Any advice would be appreciated! Title: Re: Back Wheel Steppin Out Post by: Spidey on May 28, 2009, 10:22:12 PM It is possible. You'd have to be using a lot of throttle. Other explanations include low tire pressure, improperly set-up suspension, poor road condtions, poor body position, the difference between the s2r geometry and the direct linkage of the 1100,
Let's be a bit more analytical. What do you mean by "steppin out"? Was this just one corner or did it happen repeatedly? If it happened more than once, what kind of corner was it? What pace were you traveling? Were you beyond the apex already when you thought it stepped out? When did you get on the throttle? How much lean angle were you using when it stepped out? What was your body position? Were you on the gas when it stepped out? If so, how hard? Title: Re: Back Wheel Steppin Out Post by: Jarvicious on May 29, 2009, 01:38:35 PM I'd like to hear more answers to Spidey's questions, but I had a "stepping out" problem in the few months after I got my S2R 800 (not near the power yours has) and it ended up being a suspension problem. I weigh around 215 so both front and rear were/are way undersprung for my weight.
What I noticed was that going into corners was fine (with the exception of crazy decel fork dive) and I could hold my line/speed just fine, but as soon as I hit the point where I started to throttle out of the corner, my rear started to feel "loose" at very best. My tech adjusted the rebound (I think that's the dial this piece of shit shock has on it) and later adjusted the preload for me and it hasn't happened yet, even with my more agressive riding style. Keep in mind also that your rear wheel "slipping a whole lot" may be no more than an inch or two tops. Just like when people think they just did an epic wheelie that was 2.5 inches off the ground, or even jsut decompressed the forks. Then again, I don't know your riding experience :). Title: Re: Back Wheel Steppin Out Post by: carraway on May 29, 2009, 03:50:25 PM It is possible. You'd have to be using a lot of throttle. Other explanations include low tire pressure, improperly set-up suspension, poor road condtions, poor body position, the difference between the s2r geometry and the direct linkage of the 1100, Let's be a bit more analytical. What do you mean by "steppin out"? Was this just one corner or did it happen repeatedly? If it happened more than once, what kind of corner was it? What pace were you traveling? Were you beyond the apex already when you thought it stepped out? When did you get on the throttle? How much lean angle were you using when it stepped out? What was your body position? Were you on the gas when it stepped out? If so, how hard? Thanks for taking the time to answer. Much appreciated! In reply to your questions: By "stepping out" I mean that the back wheel feels like it is gyrating from side to side. Happened in a couple of corners. There were alot of tar snakes on the road but I dont think that is the problem (am I wrong?) Wasnt using alot of lean at the time. Travelling uphill through a curve (not particularly sharp). I was on the gas but not too hard and not increasing (I dont think) throttle as I was going through the curve. Travelling about 50-60 kmp through turn bt slowed down when wheel stepped out. I was just through apex at the time of the "event" I wonder if my problem is the set up. I weigh about 150 lbs and the bike was sprung for someone weighing about 175. I didnt check the tire pressure before riding [bang] but I am guessing that wasnt the problem as I got the bike from the dealer. Thanks again if you have any other thoughts I'd appreciate it! Title: Re: Back Wheel Steppin Out Post by: carraway on May 29, 2009, 03:58:45 PM Thanks for taking the time to reply much appreciated.
By stepping out I mean the back wheel seemed to gyrate from side to side. Happend in a couple of corners. There were alot of tar snakes on the ride and it was hot but not scorching. I dont think it was the road conditions (am I wrong?). Travelling uphill at the time but not too fast. Probably going 50-60 kph in the turns. I was on the throttle but not too hard. Happend as I was at or just coming out of the apex on corners that were not too sharp. Slowed down when the wheel stepped out and problem seemed to resolve. I wonder if the problem is the set up. I weigh about 150 and the bike is sprung for someone weighng 175. I didnt check the tire pressure [bang] but I did get the bike right from the shop so I dont think that was the problem. 1600 kms on the tires so I dont think it was an oily tire issue. Thanks again for any further thoughts or advice. Any other theories would be welcome! Stop by if you get to Vancouver. Title: Re: Back Wheel Steppin Out Post by: Spidey on May 29, 2009, 05:13:47 PM Shop's often get the tire pressures wrong. Very, very wrong. Start there and report back. I bet that's the problem.
What you're describing doesn't sound like you're spinning up the rear because of too much throttle. It's correct that you can have the rear step out coming out of a turn. But you have to be pushing pretty hard (i.e. lot of lean) and be somewhat hamfisted to get the rear to spin up coming out of a turn. Based on how you described it, you weren't riding like that. It could very easily have been the tar snakes, but I'd bet it's tire pressue or suspension. 150 versus 175 shouldn't make that big of a difference. If you were 240, that's another story. If you haven't had your suspension set up for you, it's the best $ you can spend. I don't mean re-springing the whole bike. I mean paying a shop $20 or $40 or whatever to get your preload and rebound and compression properly set. Or the board can walk you through it. Preload is pretty easy and will have the biggest effect on the feel of the bike. Rebound and compression might need a more experienced eye. Also, get an eye on your tires. Do they look ok? By ok, I'm asking if there are any glaring problems -- nails, giant patches of oil, etc. While you're at it, check your chain tension as well. Make sure there's not too much slack and that there aren't any kinks in the chain (it's new, so there shouldn't be). Title: Re: Back Wheel Steppin Out Post by: somegirl on May 30, 2009, 06:29:50 PM Tar snakes can get extremely slippery when it's hot or damp out.
Title: Re: Back Wheel Steppin Out Post by: CDawg on June 01, 2009, 09:05:01 AM Slowed down when the wheel stepped out and problem seemed to resolve. If it was a traction issue (tar snake, painted stripe, etc...) when you slow down, you decrease the amount of traction available to the rear wheel potentially losing some stability. Was the road wet? Title: Re: Back Wheel Steppin Out Post by: Spicoli on June 01, 2009, 11:06:57 AM How new are the tires? Doubt it is the problem, still something to address.
Title: Re: Back Wheel Steppin Out Post by: carraway on June 07, 2009, 05:30:23 PM Hi,
Thanks for getting back to me. I have been away. Was lucky enough to ride down the Pac Coast Highway. The road from SF to Santa Cruz was amazing! The road from Santa Cruz to Carmel also beautiful but windy as hell near Salinas. CDawg's comments were interesting, as I seemed to get improved traction when I slowed down. Nice day. Road was dry. Tires have about 1600 kms on them. Does that count as new? Thanks again! Title: Re: Back Wheel Steppin Out Post by: Mr Bread on June 09, 2009, 11:30:14 AM Moto gp - Powerslides - Motorbike Drifting Lone Rider Mix (http://www.youtube.com/watch?v=DARsTJkqBXs#lq-lq2-hq-vhq)
Title: Re: Back Wheel Steppin Out Post by: Goduc on June 10, 2009, 01:45:13 PM If it was a traction issue (tar snake, painted stripe, etc...) when you slow down, you decrease the amount of traction available to the rear wheel potentially losing some stability. Was the road wet? While this is true, it isn't as true in all circumstances. He sounds like a novice to intermediate rider at best, and at those type of speeds and small amounts of lean angle the loss of traction due to braking/decel is negligable. I am thinking that it is probably a multifaceted problem that has to do mostly with suspension, new bike paranoia, and bad road conditions. Just my 2 cents. Title: Re: Back Wheel Steppin Out Post by: DarkMonster620 on June 23, 2009, 04:49:48 PM Shop's often get the tire pressures wrong. Very, very wrong. Start there and report back. I bet that's the problem. What you're describing doesn't sound like you're spinning up the rear because of too much throttle. It's correct that you can have the rear step out coming out of a turn. But you have to be pushing pretty hard (i.e. lot of lean) and be somewhat hamfisted to get the rear to spin up coming out of a turn. Based on how you described it, you weren't riding like that. It could very easily have been the tar snakes, but I'd bet it's tire pressue or suspension. 150 versus 175 shouldn't make that big of a difference. If you were 240, that's another story. If you haven't had your suspension set up for you, it's the best $ you can spend. I don't mean re-springing the whole bike. I mean paying a shop $20 or $40 or whatever to get your preload and rebound and compression properly set. Or the board can walk you through it. Preload is pretty easy and will have the biggest effect on the feel of the bike. Rebound and compression might need a more experienced eye. Also, get an eye on your tires. Do they look ok? By ok, I'm asking if there are any glaring problems -- nails, giant patches of oil, etc. While you're at it, check your chain tension as well. Make sure there's not too much slack and that there aren't any kinks in the chain (it's new, so there shouldn't be). Spidey, w/o gear i weigth 195lbs, with gear i assume 205/210lbs, i have a M620D, this has happened to me a couple of times, i own a dial tire pressure gauge[motion pro], and have the screw in the rear shock 2.5 turns from full 'hard'; the front, OEM Marzochis. when the above condition happens, is followed, not always by front end sliding, WHAT AM I DOING WRONG? tire tread 4mm Dunlop D220's it also happened whit the OEM Pirelli Diablo. i use 33psi front/36psi rear on the Dunlops and on the Pirelli's i used to use 34psi/36psi. shop tech[the one that's left] has no idea on to how to adjust suspension, trying to find #s for the other guys who knew what they were doing. Title: Re: Back Wheel Steppin Out Post by: Jarvicious on July 06, 2009, 11:58:10 AM I'm going to assume here that your bike has the same rear shock as my 05 S2R.
When you're talking about "2.5" turns are you talking about the large compression ring that you have to adjust with a spanner wrench or are you talking about the rebound (I think it's rebound) that you adjust via flathead screwdriver)? The spanner ring is only to set the preload (sag) on the shock and that kind of thing can be setup with the bike on the stand. Adjusting the rebound on mine did as much to solve the rear wheel wobbles as did adjusting the preload. I think the dial has 30 clicks if I remember and mine's set at around 23 (1 being all the way counter clockwise and 30 being all the way clockwise). I weigh 220, ftr. I normally run around the same pressures you do and for a time I was even running Shinkos with little to no slippage. Title: Re: Back Wheel Steppin Out Post by: DarkMonster620 on July 07, 2009, 05:22:04 PM I'm talking the screw you acces at the bottom of the shock; the one for dampening I think.
I mean, if I can predict it'll happen, is fun but if not, ... Title: Re: Back Wheel Steppin Out Post by: CairnsDuc on July 13, 2009, 04:18:05 PM I honestly think the best money I ever spent was having my Suspension setup for my Weight and riding style, My S2R 800 was a very nervous ride when I first got it, front forks would bottom out, the rear of the bike would wallow and slide around in corners.
I purchased an Ohlins rear shock brand new from Moto Wheels and had it sprung, valved and set up for my weight and riding style, I then spoke to a suspension specialist and ordered new springs to suit the front forks, we then played around with the oil weights and heights to get it working well with the new rear Shock. It has made the bike handle extremely well, I don't go scraping the pegs on the local mountain ranges, but I like to have fun, and the bike has now become very confidence inspiring and predictable. This has also made the bike much safer when riding around town, in an emergency situation (Emergency stop or collision avoidance) I know how the bike will react and what it will do. I would suggest talking to a suspension specialist and see what they think can be done to get the bike set up for you, your riding style and riding area. |