950 SE 17/17 Wheel Setup

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by River6822, Oct 27, 2010.

  1. River6822

    River6822 Fat kid on a 950 SE

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    I finally took the plunge and picked up a set of 17" wheels from a fellow inmate. I've read tons of threads but after about 50 miles of riding I've found opposite of what all of them state. I'm hoping some one can explain what I'm describing.

    I was very happy with the stock 21 / 18 setup. My only disappointment was the lack of street tire choice. I really wanted one setup for dirt and another for street.

    I took a trip to the Tail of the Dragon with the stock set up and had no issues. The bike cornered great, handled wonderfully and was a pleasure to ride. I guess all I'm trying to say is I'm no stanger to how the bike rolls from one corner into the next.

    I installed the 17/17 setup and took it for a ride. I'm finding the bike more difficult to turn in. All of the threads suggested that this setup is suppossed to turn in quicker and twitchier. I'm feeling the exact opposite. I really need to lean into it and make it happen.

    I've used my local Home depot parking lot to do slalom type drills. It takes more steering input to do the exact same exercise. Maybe I'm just comfortable with the stock setup but this seems slower, or more deliberate.

    I didn't find any high speed instability, head shake or anything like that.

    I'm all ears :ear .
    #1
  2. markie_wales

    markie_wales Been here awhile

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    Firstly I do not have a street set of wheels for my SE.

    Could it be that the (possibly) wider road rubber means you need to lean it more to get to the side oif the tyre? With the thinner 21" front a small amount of lean will get you a long way over onto the shoulder of that tyre. So yes, you'll need to lean more for the same turn rate.

    Just a thought.

    cheers

    Markie
    #2
  3. mcmann

    mcmann Motorcycle ADV enthusiast

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    You nailed it . . . the thinner rims and tires do turn in easier. We just got back from a trip to Little Switzerland, NC riding a 950SE (with street tires on stock rims/Battlax BT45's) and a 950SM. The SE seemed to turn in easier than the SM.

    Since I ride mostly road on my SE . . . I am ordering the 19" X 17" Canyon set up from Woodys with Distanzia's.

    The 17's give you more tire surface and should give you more confidence in the tight stuff when you get used to them.
    #3
  4. ABYSS

    ABYSS KTM

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    The 17x19 is a better setup than the 17x17. You have effectively changed the geometry of the bike by changing the wheel proporitions. This has substacnial effects on the way it handles.

    Changing to the same size wheels versus split size changes the steering goemetry. While the 17x19 isnt the same proporiton as the originals it is alot closer.
    #4
  5. Stobie

    Stobie Mr. Motivated

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    In my experience, the SE with 17's is extremely sensitive to chassis setup, including tire pressure and profile. I didn't find that my SE turned in quicker, but that the steering effort was much lighter. The smaller diameter front wheel has much lower gyroscopic stability, and reduces trail by almost 20 mm, both of which lower steering effort by a great deal. On the other hand, the wider rear tire makes the bike less willing to lean over. Didn't work for me without having to make a lot of chassis adjustments in an effort to make the front and rear work together. Overall, it seems to work better with a narrow rear wheel. The 5.5" rear I was running was too wide. Dropping from a 180/55-17 to a 170/60-17 helped a lot.

    I got it working, but all the chassis adjustments added a lot of time to the wheel swap. I've found that I'm no longer willing to ride hard enough in the twisties to make it worth the effort, and sold my setup to another inmate. I would have kept them if I were doing a permanent conversion.

    Try raising your rear tire pressure up to about 40 psi.
    #5
  6. promac

    promac Adventurer

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    Have you considered an 18" rear and 19" front? I did and I'm quite happy with the results. My setup:

    Woody's
    Front Rad hub
    Rear rad cush hub w/ carrier
    Front 2.5x19 excel custom
    Rear 3.5x17 excel custom
    Stainless spokes/nipples
    Superlace/true
    Front Mefo explorer
    Rear 150/70-18 Mefo Explorer

    [​IMG]
    #6
  7. River6822

    River6822 Fat kid on a 950 SE

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    I rode into work this morning paying attention to what was going on. I think what I'm feeling at this point is the lower center of gravity, the wider tires and the street tire profile. I might even be running too little pressure at 32psi.

    I agree that the 19 / 17 combo would be optimal, but that's not what was for sale. I've been looking for quite a while and this was the first set of wheels that fit my criteria, so 17 / 17 it is. If I don't get used to it I can always get 19" laced up, now that I have something to work with.

    I also agree that a thinner rear would work out better, both for fitment and handling. The 180 is way wide and a PITA to get in there. In fact the tire expands more than I anticipated and the plastic chain guard that had about 1/16" clearance now has a nice V groove in it from the tire. Which actually brings me to a good question. Is there a chart some where that tells what tire sizes are optimal for rim widths? I have a 3.5" up front and 5.5" in the back.

    Stobie - I know you've run the gamut with your setup. I think once I get comfortable and start pushing the bike & myself, I'll probably feel some of the stuff you were. Time will tell. I just don't have the confidence to push it over just yet, but I'm sure once I get past that fear this thing's going to be a blast.
    #7
  8. mcmann

    mcmann Motorcycle ADV enthusiast

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    I ordered the 4.25" X 17" rear with a 2.5" X 19" from Woodies. I plan on using the 17" X 4.25" rear with the stock 21" for off roading (TKC 80's).
    #8
  9. KHVol

    KHVol Long timer

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    One thing, you are running too little tire presure...34 pounds is a minimum for that setup....
    #9
  10. Bob599

    Bob599 Bob599

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    I have a 06 950 ADV not an SE. However I did borrow a set of 17inch super duke wheels that CJ Designs adapted to the adventure. I put about 500 miles on them and have to say they were great on the road. I did experience some of what your saying and after a few miles I really began to ride the bike differently. Pushing much harder and hanging in corners with fantastic stability. Never experienced any speed wobble. Really put some miles on and you may really appreciate the size.
    #10
  11. Chuckracer

    Chuckracer Jerkus Maximus

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    120 front, 180 rear are the optimal sizes for those rims.

    Bump up your pressures a little and hit the twisties. Brake late and turn it in hard...you'll see why roadrace bikes run these sizes.
    #11
  12. scottrnelson

    scottrnelson Team Orange

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    What tire did you put on the front and what size was the rear?

    Some 120/70-17 tires steer quite a bit slower than others, and the bike will also steer slower with a 180 or 190 on the rear than it will with a 170. This is all based on my experience of riding Ducatis for the last 13 years with at least six different types of tires. I remember putting a new front tire on once and the steering was like driving a truck (without power steering) compared to what I had on the bike before.

    And anytime I've put new tires on, the steering always felt heavier for a while because the old tire was always worn on the sides more than the middle, so it was more triangulated, with a narrower contact patch, therefore quicker steering.

    In any case, the stock tires on my 990 Adventure steer quicker than any of the Ducatis ever did with whatever tires I had on them.

    I recommend that you give the tires a few hundred miles to let you adapt to them before making a judgment about the steering.
    #12
  13. MrMike

    MrMike No self control

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    Scott I forgot to mention what pressures I ran with those wheels. I rode with 36F 42R which is what I've always run in big bikes with street biased tires. Try that.
    Also I was told to snap the bike into a tight turn which I did with this setup and they worked great......never got them to slide.[​IMG]
    #13
  14. River6822

    River6822 Fat kid on a 950 SE

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    I'll up the pressures and give 'er a try after work. Snapping sound EXACTLY like what needs to be done.

    The stock setup was just leaning on the bar and it would kinda just stay with you.

    This you have to snap into the turn and hold it there.

    I'll get used ot it. If you never slid them, that gives me a little something to shoot for. Not that I want to slide them, but that there will be that stability once I get my weight to the inside.
    #14
  15. KHVol

    KHVol Long timer

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    After riding MCMANN's SE last weekend, I couldn't believe how quick steering it was, almost too quick for the road. It felt like a 250 MX bike. It isn't surprising that the heavier 17's steer slower. Did you also add a caliper and rotor ?

    Like everyone else is saying, put a lot more pressure in the 17 in tires and you will see quite a difference. I run almost 10 more pounds in the big tired 17's than I run in a Berg or Honda sized SM. Running 32# and under makes these bikes steer very strange.
    #15
  16. River6822

    River6822 Fat kid on a 950 SE

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    Stock hubs / Rotors / Calipers.

    The stock 21/18 does turn almost exactly like my 450 EXC.
    #16
  17. Stobie

    Stobie Mr. Motivated

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    Exactly. Point and shoot works better with this setup than "The Pace". Your right hand will get tired after a while because of the SE's front brake power, or lack thereof. It never faded on me, but required a good squeeze.
    #17
  18. Stobie

    Stobie Mr. Motivated

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    Those are the exact pressures I settled on with my setup.
    #18
  19. Chuckracer

    Chuckracer Jerkus Maximus

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    Depending on the tires and temperature, I wouldn't get too nutty in the twisties running those kinds of pressures.

    35 or so on both ends might be better to start with.
    #19
  20. Nowwhat

    Nowwhat I'll Go Second...

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    120F/160R 32 psi both....

    could get both tires to slide predictably ....


    [​IMG]
    #20