17 inch front wheels in gravel?

Discussion in 'The Perfect Line and Other Riding Myths' started by Harry Potter, Sep 4, 2018.

  1. Harry Potter

    Harry Potter Been here awhile

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    Just how bad are 17 inch front wheels in gravel with lets say tkc80 tires? I'm thinking about dual sporting a Yamaha XSR700. Thanks
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  2. High Country Herb

    High Country Herb Adventure Connoiseur

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    Probably just fine for light dual sporting. In my opinion, the larger diameter wheels help more with rocky terrain. The angle of approach to an obstacle improves as the wheel gets bigger. The other advantage is gyroscopic stability from spinning mass further from the hub. That can be mitigated with a steering dampener if really needed.

    I had an 18" wheel on the front of my XL600R, and it did fine. It was a beast with knobbies. Because the 18 was an odd size for a front, I had to use rear tires with desirable tread patterns. A 17 will also have slim pickings in knobbies, but the TKC80 is one of them.

    I currently dual sport an Aprilia Dorsoduro with 17s, and gets around OK. It is rather tall, and over 400 lbs, so I won't be winning any hare scrambles. :lol3 The Yamaha sits lower and probably weighs a bit less, so that will make it easier. By the same token, however, it has less wheel travel and clearance, so you'll have to be careful over boulders and stuff so you don't smash those pipes.

    You might also want to do something about that oil filter. Mine is in the same spot, and I have found some very deep dents in it after gravel runs. Initially, I put a rubber cap over it and that worked well. Rubber tool handle dip would probably also work well. Later, I got lucky and found a one-of-a-kind custom skid plate.

    [​IMG]

    Pirelli MT60 (My preference for an all around tire)
    [​IMG]

    Conti TKC80 (Best for mud and soft stuff, but not good on asphalt. Also, look at the size of that front tire!)
    [​IMG]
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  3. Harry Potter

    Harry Potter Been here awhile

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    High Country Herb, Thanks for the reply. That 17 inch front wheel on the XSR700 has me thinking about a Triumph Street Scrambler but the Street Scrambler has a smaller tank and way fewer dealers.
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  4. DesertPilot

    DesertPilot Been here awhile

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    I've been conisdering going with an XSR700 for mild gravel myself. I figure it all depends on the gravel -- if it's justr a surface layer over hard-packed dirt, 17" should be fine, if it's foot-deep pea gravel over a sea of soft sand. I'll die horribly and they'll never even find my bones, no matter what I'm riding. Hmm...

    As far as protecting that oil filter goes, Higdonion makes what looks like God's Own Crash Cage And Skid Plate for the FZ07 (https://higdonion.com/products/fz07-protection-cage-and-skid-plate) -- in their photos, it looks beafy enough to protect against rocks, stones, and small land mines. I imagine this will also fit the XSR, since they must share the same frame. I'll be looking into this if I go the XSR route.
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  5. High Country Herb

    High Country Herb Adventure Connoiseur

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    Hmmm...the Triumph is about 40 lbs heavier, but has the 19" front wheel. I haven't heard complaints about their reliability.

    That's pretty cool.
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  6. dddd

    dddd Long timer

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    No problem at all with 17in in rocks, nor tkc80 on asphalt. This is to statistically cancel the above complaints.

    If there is a problem, it must be too subtle to suffer from it at the levels we mostly operate (not enduro).

    Enjoy.

    Actually, the things that I suspect could be proven less optimal are:

    a) that the front of a street bike is probably relatively heavier to its rear than a dirt bike. I mean, center of gravity is more forward, so you notice quickly that the front obstinately refuses to move when you muscle it out of mud or snow. That's easy to fault the 17in but in fact it's the front weight doing it more than the diameter. My versys is 200 lbs in front, 230lbs in back (empty tank).

    b) The fork suspension is also shorter thus stiffer and feels like it halt more than absorbs. Again, not the diameter's fault. Give plenty of front preload; you will bottom these street tuning otherwise.
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  7. High Country Herb

    High Country Herb Adventure Connoiseur

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    Those are some pretty good points, and might explain my experiences with the TKC80. My bike already has a bit of head shake, but it seems to be self canceling. When the TKC began to wear, those turned into speed wobbles that wouldn't go away until I slowed down. Maybe some rake change, or a steering stabilizer would have solved it. My other issue was stopping power. Also possibly due to the weight being more forward, the rear tire seemed to find no traction in panic stops.

    People on heavier bikes seem to have no issue.
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  8. Harry Potter

    Harry Potter Been here awhile

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    Thanks for the input guys. I have dedicated dirt bikes so I wasn’t going to try to push the limits. Just thought I might try something new and different and trade off a DR650 and a XR650L for a XSR700.
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  9. mississippimadman

    mississippimadman Long timer

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    Mine does just fine in gravel with 17s wrapped
    In tkc80s 20180828_181149.jpg
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  10. High Country Herb

    High Country Herb Adventure Connoiseur

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    I would do it if you have room for both. The great thing about that size bike is if you don't like it off road, put some street biased tires on it next time and have a ball. It would certainly have more highway capability than a 650 dual sport.

    I thought the FZ-07 had a decent motor for street/highway use, and an easy to ride UJM riding position. I loved the minimalist design of the XSR900. The XSR700 should be a great combination of the two.

    There's some decent luggage options for that bike, too.

    [​IMG]
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  11. Bucho

    Bucho DAMNrider

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    I have a DR650 with a second set of 17” wheels. On easy dirt or gravel roads I felt my motard wheels worked just as well as a “normal” skinny 21” wheel. The only exception was hard braking at higher speeds (way faster than the normal 25-30mph speed limit) the smoother 17” wouldnt brake as well. Compared to a knobby on a 21” would dig in a little better
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  12. c_m_shooter

    c_m_shooter Ninja Warrior

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    These threads make me wonder how I every get to the paved road from my house. On gravel roads those 17 inch wheels with sport touring tires can still pull a second gear wheelie for a half mile.
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  13. PeterW

    PeterW Long timer

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    Not as good as a 19", which is not as good as 21" which is not as good as 23".

    It's all tradeoffs, you can do it but the front won't roll as easily over obstacles and will get knocked offline easier and will have a harder time getting out of ruts. Provided you aren't being competitive and aren't pushing the limits you should be fine.
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  14. BetterLateThanNever

    BetterLateThanNever Long timer

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    I’m not sure I understand why wheel size matters in gravel, which I ride all the time. I thought it was more about dealing with bumps and obstacles. Reading with interest...
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  15. markk53

    markk53 jack of all trades...

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    Larger diameter rolls over objects better. A 21" will roll over rocks with less effort. That is why they are on virtually every full size off road bike built. That is a physical fact, no matter what any opinions are. Want proof, hit a few 6" logs, some deeper ruts crossways, and some good size pot holes. You will learn the difference quickly.

    A narrower wheel will knife down through deeper loose stuff better than a wider tire, the wider tire will tend to stay on top, skating on really deep gravel, loose stuff, and thicker mud. Plus in mud the narrower profile will cut forward easier. Stick your hand out a window then rotate it so the wind hits the edge of your hand versus the palm of your hand.

    You'll never see a full size trials bike nor will you see a motocrosser with anything smaller than a 21. They are functionally superior to the 19, 18, and 17 for anything involving rough terrain.

    Can you do a 17 for dual sport? Sure. It will work okay, not optimal, but fine. Now you understand the short comings.
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  16. Kommando

    Kommando Long timer

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    'Thoroughly well said.
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  17. usgser

    usgser Long timer

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    I'm no grand dirt rider but good enough to know my limits and I personally like a bigger front wheel. On loose dirt/gravel doesn't wash out on a turn as easily. Not saying 17 is small but w/o riding your bike couldn't say a bigger wheel would be better. Lotsa factors: skills, speed, loading the front end on a turn etc. If you're considering buying the bike and it's in good shape I wouldn't let a 17" wheel deter me. If you already own the bike put a good tire on it and test thoroughly. If it doesn't work as hoped adjust you riding style or swap to a bigger wheel. Either will be cheaper than buying another bike.
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  18. Brakelate

    Brakelate Supermoto Adventurer

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    Has no one heard of Supermoto bikes?

    Seems you start out asking about wheel diameters, then get further into the shortcomings of various bikes and suspensions.

    I've ridden and raced 17" wheels with everything from rain, road to race slicks on every surface on my DR-Z400SM. Ideal, perhaps not. But many race bikes run even smaller diameter 16.5"s out front. Confidence, experience and skill overcome all other issues for the most part.
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  19. BetterLateThanNever

    BetterLateThanNever Long timer

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    I get the benefit of narrower. It's the benefit of taller I don't get, given the topic was gravel. I'm well aware of the benefits of a larger diameter wheel on rough terrain and in mud.
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  20. High Country Herb

    High Country Herb Adventure Connoiseur

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    Generally, 21" tires are offered in narrower widths than 17s. Other than that, you are correct.

    I think we have the tendency to get hung up on small differences in performance. In reality, a Ninja 600 with 17" race slicks could handle most gravel roads.
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