| Author | Message | ||
     Trafford |
My 1125R gets violent shakes at over 110 mph and its worse with hard acceleration. I have checked all normal things....Head bearings, wheel bearings...I have set up suspension to 95 Kilo settings. Then tried increasing preload at from end to 9 from 7 turns. If I slide back on the seat it is marginally better. I have put my weight over the bars when it starts, I have relaxed grip to almost nothing when it starts....etc etc. I have been riding fast bikes all my life and this is a fairly new thing for me. I had fairing lowers and a double bubble screen and have taken these off in an effort to eliminate things. I had new tyres professionally mounted and balanced. Two up it does not seem to happen but I rarely go that fast with 'her' on the back hahah. Any ideas?? (Message edited by trafford on June 28, 2010) | ||
| Trafford |
From 'Visor Down ' Test On slightly bumpy back roads or during bouts of fierce acceleration the Buell suddenly breaks into a fit of flapping bars with no prior warning. This episode starts as a fast wobble and never quite breaks out into a full-on tank-slapper but it's unnerving when you're trying to make progress down a country lane and you end up having to ride around the problem, shifting up and keeping the engine revs low appears to keep the 1125R in a calmer state of mind. Read more: http://www.visordown.com/road-tests-first-rides/fi rst-ride-buell-1125r/5981.html#ixzz0s8ulnkwJ | ||
| Ponti1 |
Definitely not a typical characteristic of the motorcycle. My 1125R is smooth as silk WAY past 110 MPH, regardless of RPM at which the engine may be spinning. Did you start by setting suspension exactly as indicated in the manual for your weight? | ||
| Trafford |
Yep....as I said at the top of the thread.....95+ kilo with clothing. Ponti what tyres are you running?.....what pressures? I have new Michelin Road pilot 2s running 34 front 36 rear (Message edited by trafford on June 28, 2010) | ||
| Dano_12s |
Trafford,has the bike always done this? | ||
| Jjk |
Hello Trafford, I have a CR and noticed some similar issues when I first got it and I would suggest reducing the rear rebound damping little by little until it feels better. I think the recommended rear rebound setting does not allow the bike to recover quickly enough and by relaxing the rear rebound, the shock can 'return' more quickly. I would stick with the stock preload settings, by the way, as increasing the rear will effectively raise the rear of the bike making it even more front-end biased which can cause instability. Or if you REALLY want to tackle the problem, get an Ohlins TTX shock for it. It absolutely transformed my bike. Better traction, smoother action over bumps, calmed the front quite a bit (don't forget these bikes will never, ever be as a stable as an ST1300 or something). Good luck! | ||
| Trafford |
Thats a good question...... I never had much chance to get up to higher speeds using it here in the Netherlands. I am pretty sure its the tyres as these were fitted when I went to the UK and since then I have become aware of the phenomenon. I will swap front wheels from my XB12R and see if its the same or different....it may give a clue. | ||
| Jng1226 |
Good points here already. What bike did you come from before the 1125R? When I first got into Buells after years of European sport bikes (Aprilia, MV, Triumph) I noticed a high-degree of sensitivity to steering inputs that required me to change my riding style somewhat. I concentrated much more on not pulling myself forward on the bars and using my legs to move around when needed in setting up for corners. With 21 degrees of fork rake and a 54.1 inch wheelbase, the geometry of the 1125R is more aggressive than most other sport bikes. My 1125R is more "stable" than my XB9SX but still is more sensitive than any previous bike. The XB9SX was my first Buell and with the same fork rake but only 52 inches of wheelbase it is extremely sensitive to inputs on the bars. I've had my 1125R on track and there are some fast sections (140+ MPH) at Jennings GP in Florida. On some the faster corner entries where you are trail-braking into the corners and the last turn of the track where you are accelerating at full throttle through 3rd gear I do notice a slight weave that can be disconcerting, as if the bike could start tank-slapping with just a bit more aggressiveness. If I were racing the bike and going for maximum lap times I would at least invest in the Ohlins steering damper kit from Eric Buell Racing. Also, the racing parts include replacement steering cups that provide more offset and therefore more trail, also adding stability. I have also seen racing setups with true clip-ons and machined upper triple clamps to lower the bars and bring them inward a bit to reduce the leverage and also move more weight forward and down. For one rider, he claimed this modification alone made him 1-second faster at the track. In addition the suspension adjustments mentioned above, I would try to also focus on as little extraneous input on the steering as possible and see if that helps. Jeff | ||
| Ogobracing |
Interesting comment above because I've found the 1125R more straight-line stable than some other serious sport bikes I've ridden, which seemed a bit "twitchy". I do have a steering damper, but I've found my bike incredibly stable at speed with no front end vibration or twitchiness at all. | ||
| Jng1226 |
Just to clarify, I meant that when on track with the stock 1125R at speeds above 100 mph I felt instability as a slight weaving of the steering when trail-braking (hard braking while turning the bike) from high speed (140+) into a turn and also when accelerating out of a high-lean angle turn at full-throttle through 2nd and 3rd gears. On the straights at maximum speed the 1125R felt just as stable as any other sport bike I have ridden on track. Jeff | ||
| Trafford |
Thanks for the inputs. My three previous bikes were XB9R which was stable, GSX1000R K5 which easily recorded 170 mph on gps equipment before I had to slow for a car on a German autobahn...stable too, and XB12R 2006 which I still own and is not nervous at all!! That's why this is a surprise for me, as that has even shorter wheel base and the sharp steering angle!. I have tried this high speed acceleration with a firm grip.....and almost no grip....its the same. The only slight improvement comes when I slide back to the passenger hump which is around 2 inches further back from my normal comfort position. I would prefer to avoid a damper as this will cover the real issue. I have tried to ride through it but believe me it just starts to get more violent and I do not want to go down on the highway at 120mph plus.... | ||
| Gofastalot99 |
Mine does the same as you describe. I have played with the suspension settings slightly, changing them from the as-delivered settings to the factory recommended for my weight. I have yet to check to see if that will make a difference. I may also adjust the tire pressure slightly. | ||
| 1125rcya |
I am no one but this is what id look for. check the front rim for balance. Make sure the weights are on the same side as the caliper. Make sure there are no wheelie bumps in your front tire. I know the feeling of a hight speed wobble and its not anything to play around with, youll wake up with broken bones. | ||
| 1125rcya |
Oh im not sure about the rear tire but make sure its not dog tracking, that it is straight. | ||
| 1125rcya |
check to make sure your front wheel bearings roll smooth. | ||
| Duphuckincati |
These things are on the nervous side for sure. Eslick's "factory" race bike had 1 degree more rake (22 degrees) and a bit longer wheelbase. Get a ride on a Norton Commando then ride the Buell. It'll feel rock steady after that! | ||
| Trafford |
It may be nothing or something. Its a brand new tyre....no flat spots and no wheelies. I just checked roundness and at one 3 inch part of the tyre it is 1/8inch lower than the rest of the circumference. It appears to be seated evenly on the rim so this could be my problem, even though it would not normally ring alarm bells. Its only that I am looking for any small irregularity. Bearings are spot on. Rear tyre on inspection seems fine. | ||
| Fast1075 |
I seem to remember another rider that had stability issues after switching to PR2's. But thats all I remember...sorry nothing specific....he fiddle with the suspension and tire pressure and got it calmed down... | ||
| Trafford |
It would be good to know the tyre pressures for P2s. I am using the pressures listed in the handbook for Pirelli's. I searched but found nothing specific for Michelin and 1125R | ||
| Rt_performance |
I had the issue after switching to pure powers. the light weight carcass added to more traction seemed to make my bike skip the front tire frequently. I tried adjusting the suspension and air pressure with no luck. I found a dealer that gave me a discount on a GPR damper. It makes the bike much more enjoyable to ride. was about 145 on the highway this weekend and could have easily went more .  | ||
| Trafford |
Rt_performance- thats the sort of info I was after....first hand experience! What pressures are you running? | ||
| Ron_luning |
I had a very similar problem start after mounting a set of Michelin Pilot Road 2's front and rear. I mounted and balanced them myself, as I did the previous set of Bridgestone BT015 (I think that's what they were anyway). The wheel weights are on the same side as the brake rotor. At the same time I installed the PR2 tires, I put on a Zero Gravity Sport Tour screen. As a result I wasn't positive the tires were the cause, but with your experience of removing your aftermarket shield and the problem remaining I'm pretty sure it's the tires. Mine will wobble around 115-120 mph but then smooth out after that. I haven't had it much past that though since it has been on the street only with these new tires. I won't be buying these tires again. | ||
| Blur |
This is one reason why I want a damper for this beast. I adjusted some of it out by messing with the suspension but still don't feel as confident if I had a damper for it. | ||
| Xb9er |
maybe a belt shifted in your tire | ||
| Rt_performance |
I tried moving the pressures up and down it grips better with a pound less in the rear. I called the shop that mounted my tires to be sure they spun them on a balancer.since they had no wieghts on them he checked with the tech and respond yes twice(he couldn't believe they where perfect either). I absolutely love these tires after. They grip more and it makes it easy to skip the front tire. Damper made this bike much more comfortable. I like the fact i can easily adjust it on the fly. they can be had on ebay for what i paid for mine but i wanted blue body with Black adjuster and needed it before i went to nc last month | ||
| Trafford |
So I wonder who else has fitted Michelin Pilot IIs . I would love to hear if they are getting the same problem as me and you guys who responded. Up to the wobble speed the tyres are brilliant. Grip/wear and general feel is wonderful. Its sad if the are just not suited to the bike. As I have already said...I can swap the front wheel from my XB12R and see what happens. If it improves or disappears then I have the full answer. I may get a chance to try this weekend but its tight as I have a road trip starting next Tuesday and I would prefer not to start wheel swapping when I have other stuff to do. If others are having the same issue with these tyres we should put a warning out. | ||
| Jng1226 |
Hopefully you're zeroing in on the problem. If it turns out you have to change tires to solve the problem, I can state from experience that the Dunlop Q2 (US name, not sure if there is a Euro name) is a fabulous street tire for the 1125R. It has very neutral steering characteristics and tremendous grip, while having 2 compounds and the wear is showing very little so far for such aggressive riding. Here is a video of a friend on an R1 following me on my 1125R using these tires on a mountain road. The camera is on his R1 and you can hear how hard he was riding to stay close. I had no idea that he was sliding in places until I saw this video, because I was going at a relatively comfortable fast pace and had no slides at all, even when going hard on the throttle exiting some tighter corners: Jeff | ||
| Trafford |
Thanks Jeff I am pretty convinced its the tyres as I never noticed it on the originals. Great film and great roads. Thanks for your input. Trafford | ||
| Ecm1125r |
Hey there. I just put on a set of PR2s and now my front end feels twitchy as well. My suspension is set to my weight per the book, tires are spot on for balance. took them off twice (just to check).I have tried to fiddle with the tire pressures too. Even Michelin was no help they said "It just takes aprox 250 miles to break in." With the oem wheel no issues. I hope that these tires get better. I got them for the mileage but I hope it isn't alot of twitchy miles as it's a little unerving. | ||
| Trafford |
Thanks for your info. It scares the hell out of me when the whipping front end starts. I tried to accelerate through but it just increases in violence especially at WOT acceleration. So for now I have a 1125R with a top speed of around 115 hahahh I will probably put them on my XB12R and buy a new pair of a different brand. (Message edited by trafford on June 29, 2010) |
