| Author | Message | ||
     R2s |
It seems some people are lowering the front for quicker steering. Ducati today at Indy raised the front of Hayden's bike for less steering effort. Can anyone confirm that this is correct about what these changes can do. I think that my 1125R has quick enough steering stock. It steers more and with less movement of the bars but it takes more effort than other bikes I've owned, especially my last track bike which was an SV650S. I would like to make the bike steer with less effort, a lighter feel. The SV was a great handling bike and if I could get the feel of the Buell closer to it but with the Buell's power it would be awesome. | ||
| Tpoppa |
The steering can be made more sensitive by: -reduce front preload, -increase rear preload, or -raise the forks a few mm in the triple trees. But too much is a bad thing and can cause stability issues. I would imagine that Hayden's GP bike has a state-of-the-art steering damper that solves any stability issues. | ||
| Ccryder |
As Tpoppa said there are a few ways to make the steering more sensitive besides lowering the the triple trees on the forks. My suggestion is to try what Tpoppa suggests and tweak your settings. I find that my 1125rt is very light in handling and quick to turn in without being unstable. I have just recently ridden another 1125r and it displayed more resistance to turn than mine. This other 1125r has not been set up for my weight and riding style. BTW: From what I heard, Hayden's steering "pipe" offset or angle was changed to help his turn in. | ||
| Velocity |
R2s, I just raised mine 5mm to see the difference (not much). Went for a total of 10mm man I'm happy, mine seemed to take too much effort to turn in and hold my line. I also change preload. Scott | ||
| Blake |
Yes, raising the forks will reduce required effort on the handlebars through a turn, but it will also reduce feedback from the front end too. If you are not concerned about pushing beyond the limits of the front end, then no worries. Just know that if you reduce front end feel too much, you will have little to no feedback from the handlebars when the front grip starts to go. With some effort on the bars required to keep the bike turning, when the front starts to lose grip, you can immediately feel the level of effort decrease indicating that the tire is beginning to slide. More important on a track where you are braking to the apex while leaned hard over. Not so vital on the street where hopefully braking is finished well ahead of tipping it into a turn. | ||
| Blake |
Be careful. Raising the front can also impair stability, tank slappers are no fun. | ||
| Cringblast |
I think this is how the CR feels for lack of better words "twitchy". Watched the suspension set up vid on Buell's web site and have adjusted per the manual for my weight but the steering seems way to responsive. The XB12R steering is great and feel totally comfortable with it. The CR well, don't know enough or know anybody local to help set the CR up to where it feels comfortable. Maybe am just used to the XB12R. | ||
| Xb1200rick |
Cringblast. I just switched from a xb12r to a 1125CR . also and have been trying to get the bikes to feel the same . I had the xb set up by the Shaun Higbee set up sheet, with all the recommended changes for improved quickness and easier cornering. I set up the CR by the book for my weight and then added the changes for improved quickness and the bike seemed to drop in too fast and did not feel stable.I added 1/2 round preload back to the front and it feels just right so far , very similar to the xb. Rick | ||
| Cringblast |
Xb1200rick, from what I had been reading and vaguely understand seems preload changes is what I am gonna do. Just put a new set of Pirelli's on so would be a good chance to check it out, if it stops raining this week. A half round increse made a big difference ? C. (Message edited by cringblast on August 31, 2009) | ||
| Xb1200rick |
A half round increase made a big difference ? with the bike set up with the added quickness settings it felt like it fell in too fast and wanted to fold up . it felt like I had to keep pressure on the bars to keep it off the tank. Added 1/2 round to the preload and it feels much better Rick | ||
| R2s |
Thanks for all the responses. I started with the book set up and have lowered the front by adjusting preload some. It hasn't quite achieved the results I was looking for. It still requires more effort than I would like. The commentators for MotoGP said they raised the front, lowering the front tubes to make Nicky Haydens bike turn with less effort. Also SportBike Magazine lowered the front tubes 10mm , flush with the top of the clamps. They claim it made the 1125R steer like the 1098. This goes against all things I've been reading on this site. It would seem from this that lowering the front ( less rake ) will make a bike turn quicker as they say, taking less movement to turn the same amount making the bike less stable and more on the twitchy side. And Raising the front ( more rake ) I thought would make it turn with less effort according to Sport rider and Doug Polen. I guess I could just experiment, but that would not be safe or a good use of my time. I was hoping we might have a tuner guru among us who could describe what effects both raising and lowering the front end would have. | ||
| Rsh |
If the sport bike magazine you are referring to is Sport Rider, they did effectively increase the rake by sliding the fork tubes down in the triples so the top of the tubes are flush. These are the settings they used: FRONT Spring preload: 12 turns out from full stiff; rebound damping: 3 turns out from full stiff; compression damping: 2 turns out from full stiff; ride height: set fork tubes flush with triple clamps REAR Spring preload: position 5 from full soft; rebound damping: 4 turns out from full stiff; compression damping: 20 clicks out from full stiff. The claimed rider weight is 150Lbs dripping wet. The following are Sport Rider's impressions: Seeing as how we took delivery of the bike less than a week prior to our track day, we'd have to reverse our normal SOP and look at how the bike's racetrack manners performed on the street. Immediately it was clear that the factory suspension settings were off the mark. Turn-in was slow, and once leaned over, constant input on the bars was required to keep the bike on its side. Trailbraking was nearly impossible, as the bike would stand up almost violently on the brakes. A testament to the strong ZTL brakes on the Buell, to say the least. To fix this we dropped the fork tubes approximately 10mm until they were flush with the triple clamp. That effectively raised the front of the motorcycle and made it less resistant under turn-in. With the addition of slightly more preload in the rear shock, the 1125R took much less effort to turn in, held its line without constant bar inputs and exited the corners without running wide under power. A dramatic improvement, though overall steering still felt slow and heavy compared with the likes of the Ducati 1098. (Message edited by rsh on September 01, 2009) | ||
| R2s |
That's the one! It seems opposite to what they did on Eslick's bike and what most are saying here. I'm just trying to find the definite answer. | ||
| Blake |
Careful, they are adjusting for hard braking AND cornering simultaneously. That is a different situation entirely from what you are likely to encounter on the street. Hard braking compresses the front, effectively lowering it a lot. If you are adjusting for aggressive trail braking into the turns at the race track, then follow the sport rider method. If you are just interested in tailoring the handling for the street to your liking, then try what we've suggested above. Drop the front a tad. Be careful! Go baby steps. Use the preload adjustements to experiment, then when you figure out how much it takes, adjust fork height accordingly and adjust preload to achieve optimum ratio of rebound to compression travel (optimum sag). | ||
| Rsh |
Eslick's bike has offset bushings installed in the triples which changes the rake. That is a personal preference that obviously works for him. Attack Performance used to sell standard and offset bushings that worked with the slick XB triple clamps they sold a few years back. Hals used them when they raced the formula extreme class. Trojan also sells version for the XB's, I have not checked if they have a 1125 offering. As Blake has pointed out, what works on the track is not necessarily good for the street and vice versa YMMV. | ||
| Tpoppa |
You can also experiment with tire pressure. Raising front pressure a pound or 2 might make the steering a bit lighter, you might like it you might not...it's personal preference. | ||
| Parrick |
I lowered my front end by 5mm a while back. By my measurements vs. published fork travel anything much more than 5mm puts it into the range where the plastic fender can make contact with the air intake scoop. I wasn't comfortable going much further than that. I ultimately decided the steering difference was minimal but the rear end got noticeably lighter on heavy braking. I took her back up to a 3mm drop, adjusted sag and riding style a bit and now I'm happy. This bike will probably never feel the same as the SV650 for a number of reasons (Height, weight distribution, C.G. setup, etc.) I have an SV1000 and I like her too but they definitely have a different feel and perform better with slightly different riding styles. | ||
| R2s |
Seeing as how we took delivery of the bike less than a week prior to our track day, we'd have to reverse our normal SOP and look at how the bike's racetrack manners performed on the street. Immediately it was clear that the factory suspension settings were off the mark. Turn-in was slow, and once leaned over, constant input on the bars was required to keep the bike on its side. Trailbraking was nearly impossible, This tells me they were actually riding it on the street, and weren't able to get it to do much trail braking. Not that they were setting it up for it. I did read about the offset bushings, that's a good point. you would have to know what way that changed it first. As far as what changes in height, ( both up and down on the fork tubes)and exactly what results you would get I haven't heard yet, but I do appreciate the answers. | ||
| Avc8130 |
Can someone tell me what the factory fork height is? I tried searching in the service manual, but it just says to make sure the forks are equal in height. ac | ||
| Rsh |
The forks have height alignment lines/marks on them. I believe the standard height above the top triple clamp is 13 millimeters, the second line down from the fork cap. | ||
| R2s |
I did a little research on rake and trail numbers and I think this explains It a bit. 2009 bike's rake / trail Suzuki SV650____25.5/ 3.9 Suzuki GSXR1000_24.8/ 3.9 Ducati 1198______24.5/ 3.8 Aprilia RSV4_____24.5/ 4.1 Kawasaki ZX6R___24.0/ 4.0 Honda CBR600RR_23.5/ 3.8 Buell 1125R______21.0/ 3.3 I went from a sportbike with the most rake available to the bike with the least amount of rake. Not that I don't like the way the 1125R feels, Its just gonna take some getting used to. I would bet that the offset bushings on Eslick's and the other team bike's are to raise the amount of rake on the 1125R's. SportBike magazine might have been on to something after all. By raising the front end of the bike by lowering the fork tube's it will slightly increase the rake and trail. Its hard to know how much it will changes it though, probably not by much. This is the direction I think I'll go. | ||
| Tpoppa |
I would imagine that the lighter feel of the SV is probably due (in part) to less rotating mass of the smaller v-twin mill. | ||
| Rsh |
I read in one of the Daytona sport bike test's when the journalists got to ride the race bike's that Eslick's offset is a .5 degree, Barney's bike is 1 degree. It was done not necessarily for the added rake but to gain additional trail. | ||
| R2s |
That's very possible. I've read that it's the trail that has more effect on handling than the other factors. The trail being the amount that the contact patch or axle trails behind the line of the fork angle were it would contact the ground. The further back the more stability and harder the steering is. Closer or less trail will mean less stability and a lighter feel. The SV has a large trail number and still fairly light steering. The 1125R has little trail and still has a lot of stability and needs more pressure to steer. Does this make since? | ||
| Rsh |
In your case if you had a very good handling SV, you would have had the forks dropped a bunch and have adjustable rear ride height to raise the rear. The Buells' XB's and 1125 do well with added rear ride height. Except it will cost you a new rear shock, 5 millimeters added length to the rear shock will open your eye's. (Message edited by rsh on September 02, 2009) | ||
| Ccryder |
Anthony: On the 1125 there is a snap-ring on the forks. Stock position is to have the top triple clamp in contact with the snap-ring. If you don't remove the snap-ring you can't have more of the forks exposed above the top triple clamp. | ||
| Avc8130 |
CCryder, do you have a pic of this? I don't see this mentioned in the service manual. ac | ||
| Crackhead |
so sport bike reduced the Axle to Crown and raised the rear to increase the headset angle? to provide less trail or an effective increase in offset? sorry for the term confusion, I come a bicycle background. | ||
| Ccryder |
AC: I don't have my 1125 with me today. It's actually kinda hard to see since there is a generous chamfer on the bottom side of the top triple tree. I saw it when I installed the clamps for my Convertibars.  You can't really see it in this pict but it's below the triple tree and above the Convertibar Aluminum clamp on the fork tube. Neil S. | ||
| Velocity |
Here is a cell pic of the snap ring once the tubes are lowered 10mm. Scott |
