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  1. #1
    You know my steez...
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    I need more traction!

    I need some help with set up to help prevent (or just lessen) wheel spin when climbing. Where I ride is dry, sandy and rocky so of course I'm going to spin sometimes, but it seems like I'm spinning out more than my non-Mojo riding buddies (that can't be right!)

    I weigh 160. My Pro pedal is set on 1. I don't know how much air is in the shock but my rubber band indicator for sag never moves lower than 2/3's of the way down the shaft. I don't stand while climbing. I have Kenda Nevegal tires inflated to 40 lbs front and rear. I sit more or less in the "middle" of the bike- I don't lean back or forward.

    Any suggestions?
    I'm unique, just like everyone else....

  2. #2
    antipodean
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    Have you set the sag on the shock and do you own a shock pump with a gauge?

    The stroke length is +/-57mm so you are looking for 15mm to 17mm sag when you sit on the bike at rest for a active rear end.

    Try this and turn off the pro pedal and drop the tyre pressure. Try 35psi for a start and then see how low you can get before you pinch flat.( Better still run a Stans kit and go tubeless).

    As far as riding style goes a little body english on the loose stuff helps. A little input back and down through the bars in time with the pedal stroke helps to weight the rear wheel and give it bite.

    Try one thing at a time though so you know what effect it is having.
    But as to the fable that there are Antipodes, that is to say, men on the opposite side of the earth, where the sun rises when it sets to us, men who walk with their feet opposite ours, that is on no ground credible.

    saint augustine 354Ė430

  3. #3
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    I agree . It sounds like too much air in your rearshock,ad lots too much air in your tires. I weigh 185 with gear and run my Nevegals at 30lbs or less . 2.1s and 2.35s. Harry

  4. #4
    Founder: Dirty3hirties
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    I have always thought that even before the new generation high volume tires and the current trend to go bigger, that 40 psi was way too much. Granted, i'm talking about being in the 170 and under weight range of course. Getting a flat every now and then is unavoidable, but if you're sacrificing the ride quality for getting just a few less flats, that's not a compromise i'm willing to make.

    I'm not saying that's the only problem, but from the OP's info, that factor stood out to me the most. Oh yeah...try riding w/o any propedal. easiest adjustment to make.

  5. #5
    bi-winning
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    Lower your tire pressure. Make adjustments to distribute your weight better. Lower your centre of gravity. Bring your forearms close to parallel with the hill. This will allow you to keep your front end down, while still keeping weight on the rear.
    When under pressure, your level of performance will sink to your level of preparation.


    Shorthills Cycling Club

  6. #6
    Green Mojo
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    Absolutely, positively decrease your tire pressure. I weigh 158 pounds. I always run about 24 psi, and never above 27 psi (tubeless).

    Other suggestions are good, but tire pressure will make huge change for the better.

    Enjoy!

  7. #7
    www.derbyrims.com
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    Quote Originally Posted by bikerneil
    Absolutely, positively decrease your tire pressure. I weigh 158 pounds. I always run about 24 psi, and never above 27 psi (tubeless).

    Other suggestions are good, but tire pressure will make huge change for the better.

    Enjoy!
    I'm 200 lbs and run about 26/30 and 5 psi higher at most if really jagged rocky, front/rear with tubes or with Stans tubeless (better feel and almost no flats with tubeless).

    A lighter weight rider could go a few pounds lighter in pressures than me (you lighter riders get all the benefits!).

    Your climbing technique matters too. You are probably only spinning the rear when standing and weight is less on the rear, so you need to pull up on the handlebar with feel on the side you are pedaling side to side as you pedal to leverage your weight back on the rear tire.

  8. #8
    It's the axle
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    You can't get traction on marbles.

    Look for a line with the least amount of loose stuff. I actually went out on my Honda 110 one time with my roofing gravel rake, and cleaned up the trails. Sometimes when it's steep enough and loose, the marble phenomenon just won't allow traction no matter what. But technique plays a pretty big role. Sometimes you clean a section that you never could. That's why I love biking. But there have been times when I hit the ground cursing. Haha.

  9. #9
    MTB Monkey
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    Pull back on the bars in time with your power stroke, which will push the rear tire down. And push a bigger gear, which will reduce the torque on your back tire.

  10. #10
    You know my steez...
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    I'll take your advice!

    Thanks for all the great advice. I suspected that my tire pressure was too high, but 40 psi is actually the MINIMUM recommended pressure printed on the sidewall. I see now that 40 psi doesn't work on my trails. I'll definitely lower the pressure based on all you guys' advice.

    I also agree that pushing a bigger gear would help although that's not always possible on really steep stuff.

    I'll check the sag too. I don't stand while climbing but I will try to get more weight on the back end.

    Thanks again, every response had useful relevant info.

    BunnV
    I'm unique, just like everyone else....

  11. #11
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    Smile

    which way to you have your rear tire postioned? you want to run it opposite from the
    front for better traction and braking in the real loose stuff. make sure your rebound
    is set correct, if it is to slow or to fast, this won't help.
    Mitch
    Boise

  12. #12
    flow where ever you go
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    Quote Originally Posted by BunnV
    I sit more or less in the "middle" of the bike- I don't lean back or forward.

    Any suggestions?
    In addition to all the great advice here, move your butt forward and back as needed to have perfect balance and traction. If the terrain is steep enough to loose traction under power, it may be steep enough to necessitate your body inching forward on the seat. At times the best position is actually forward enough that you are planted on the tip of the saddle, or even off the saddle tip, for the best balance and traction. This gives similar results as rkj_'s advice on bending forward (and they can be used together).

    Lastly, try and smooth out the peddle stroke so you can "feel" the traction and not upset it with varying degrees of force - and don't stop peddling when you spin to give the tire a chance to grab again.

    "I must not be crazy because I'm seriously questioning my sanity"

  13. #13
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    sag

    Lots of good suggestions here...

    Try 140 - 145 psi in your Float RP23 to start. That should get you in the ballpark. Agreed on the tire pressure reduction as well. If the contact patch is bigger you can be on top of a "marble" and still eek a bit of traction out of the situation....

    H

  14. #14
    mtbr member
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    Quote Originally Posted by mtbmitch2
    which way to you have your rear tire postioned? you want to run it opposite from the
    front for better traction and braking in the real loose stuff. make sure your rebound
    is set correct, if it is to slow or to fast, this won't help.
    Mitch
    Boise
    Reversing the rear tire will decrease braking traction. It may slightly increase climbing traction though.

    As for the original poster - sounds like you need more sag.

  15. #15
    KevinK
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    Kenda tires would spin constantly when I hammered...

    on uphill rocky, semi technical, or loose dirt. I tried lower pressure, and nothing helped. I have since switched to WTB Weirwolf tires UST. They are like glue when going hard on ascents. Always great traction on any trail, did I say any trail! I meant it!

    With UST tires, you can run very low pressure, but, I run 35psi, which is high for UST, but, thats my personal preference.

    Good luck,

    Kevin

  16. #16
    You know my steez...
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    the sag was off....

    Quote Originally Posted by captainnemo
    Have you set the sag on the shock and do you own a shock pump with a gauge?

    The stroke length is +/-57mm so you are looking for 15mm to 17mm sag when you sit on the bike at rest for a active rear end.

    Try this and turn off the pro pedal and drop the tyre pressure. Try 35psi for a start and then see how low you can get before you pinch flat.( Better still run a Stans kit and go tubeless).

    As far as riding style goes a little body english on the loose stuff helps. A little input back and down through the bars in time with the pedal stroke helps to weight the rear wheel and give it bite.

    Try one thing at a time though so you know what effect it is having.
    I checked the sag and it was 12 mm. I let air out until it measured 16.51 mm. I'll start with that and I'll also reduce the pressure in the tires to 35 and see how that works.

    I appreciate the good info.
    I'm unique, just like everyone else....

  17. #17
    Grams Light Bikes
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    I weigh about 155 and I use 125lbs in the RP23, maybe go to 130 for your weight. I would recommend going to a tubeless system also. I suggest some method like the Stans or Eclipse. Refer to The Tubeless tire world for moe information. UST tires are just to heavy. I have UST rims and prefer to go tubeless with normal tires, they are lighter then the UST tires and you have a lot more variety for ties choices. I always use 30 and sometimes 32 in the tires. Using a tubeless method lets you run a lower pressure with out pinch flatting.

    Also having a nice new set of tires always help!

    I also concur that keeping weight stuck up on the nose of the saddle helps when it steep and pull on the bars and drop your helps helps torque the power to the rear wheel.

    Peace.

  18. #18
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    [SIZE=2]I have always run 40psi in the tires because I prefer a slightly harsher ride and I like to let the suspension do the work.
    It would appear that Iím the only person on here who has read the scientific study on this.
    The study says that 28 psi is the optimum tire pressure for grip, rolling and tread life for a standard compound tire with an average weight of (I live in England so I donít work kilos pounds or lbs) 12.5 stone if you live in England you can translate that but Iím an idiot so I cant. Below 20 and above 35 psi results in shorter tread life because of increased tread flexing which also causes higher rolling resistance at lower and higher psi.

    I hope this makes sense, I saw it in a magazine about 3 years ago.
    [/SIZE]

  19. #19
    flow where ever you go
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    Quote Originally Posted by pastajet
    I weigh about 155 and I use 125lbs in the RP23, maybe go to 130 for your weight. .........

    Peace.
    Same here. I was surprised to see Hans recommend 140-145psi. However, now that I have the medium compression RP23 (previously had high) I have been hitting full travel regularly so I may bump it up a bit to see what happens.

    "I must not be crazy because I'm seriously questioning my sanity"

  20. #20
    You know my steez...
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    Quote Originally Posted by EGF168
    [SIZE=2]I have always run 40psi in the tires because I prefer a slightly harsher ride and I like to let the suspension do the work.
    It would appear that Iím the only person on here who has read the scientific study on this.
    The study says that 28 psi is the optimum tire pressure for grip, rolling and tread life for a standard compound tire with an average weight of (I live in England so I donít work kilos pounds or lbs) 12.5 stone if you live in England you can translate that but Iím an idiot so I cant. Below 20 and above 35 psi results in shorter tread life because of increased tread flexing which also causes higher rolling resistance at lower and higher psi.

    I hope this makes sense, I saw it in a magazine about 3 years ago.
    [/SIZE]

    12.5 stones = 175 pounds according to this ...http://www.calculateme.com/Weight/Stones/ToPounds.htm

    28 lbs seems very low to me but I'm used to high pressures in road bike tires. Everyone on this thread seems to agree that lower pressures work better.
    I'm unique, just like everyone else....

  21. #21
    mtbr member
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    [SIZE=2]Donít even get me started on road bike tire pressures, I once tried a road bike and had a blowout on the front tire, thatís the first time Iíve ever seen what looked like a puff of smoke come out the tire, must have been about 55-60psi.

    Anyway, I agree that 28 sounds very low, I have tried it at 28 and though it felt to me that it was better I didnít like the bouncy feel on ďtransit to the trail roadsĒ so I keep it at 40 and then let it run down to about 32 over a few weeks.

    I think they may have failed to take into account other riding surfaces away from England cos Iíve had a look and it was carried out in Yorkshire which is rocks and relatively hard dirt.
    [/SIZE]

  22. #22
    Mojo0115
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    Quote Originally Posted by BunnV
    12.5 stones = 175 pounds according to this ...http://www.calculateme.com/Weight/Stones/ToPounds.htm

    28 lbs seems very low to me but I'm used to high pressures in road bike tires. Everyone on this thread seems to agree that lower pressures work better.
    I am 185lbs and run my Kenda Nevegal 2.35" tires at about 32psi. I used to run them (tubeless) under 30psi on my old Fisher Cake. I ride a lot on really steep slickrock which is very high friction, but I also ride a lot of much steeper lose stuff as well. When my wheels spin it is almost always because of my body position.

    IMG_1799.jpg

  23. #23
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    Body positioning, gear selection and pedalling technique will likely help you a lot more than tire pressure. I run my Nevegal 2.1's at 50psi and have no traction issues in dry conditions regardless of terrain ... wet surfaces would benefit from a somewhat lower psi, but I don't bother.

  24. #24
    mtbr member
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    Quote Originally Posted by MacGiv'er
    Body positioning, gear selection and pedalling technique will likely help you a lot more than tire pressure. I run my Nevegal 2.1's at 50psi and have no traction issues in dry conditions regardless of terrain ... wet surfaces would benefit from a somewhat lower psi, but I don't bother.
    [SIZE=2]

    What tubes are you running?

    I like your name, especially if its something to do with the Simpsons.
    [/SIZE]

  25. #25
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    Quote Originally Posted by EGF168
    [SIZE=2]

    What tubes are you running?

    I like your name, especially if its something to do with the Simpsons.
    [/SIZE]
    The tubes are Continental 26 x 1.75-2.5 Presta Light.

    Interesting guess about the name ... but it's actually something even funnier (on a personal level).

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