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  1. #101
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    Quote Originally Posted by geraldooka View Post
    I no longer have it but I suspect the can was the correct one. Craig is quite knowledgeable I can only imagine he would have advised if that were indeed possible and I didn’t already have it installed or it was advisable to do so.
    It pretty clearly says Debonair on Debonair cans. And it's pretty simple to purchase a standard can from Sram's parts catalog.

    I guess my main point in mentioning this in the thread is that if you have problems with bottom bracket height that could possibly be solved by reducing static or dynamic sag, I would certainly try replacement air cans if available before I buy a new shock, or a new frame, or a new complete bike.

  2. #102
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    Quote Originally Posted by ColinL View Post
    I guess my main point in mentioning this in the thread is that if you have problems with bottom bracket height that could possibly be solved by reducing static or dynamic sag, I would certainly try replacement air cans if available before I buy a new shock, or a new frame, or a new complete bike.
    Agreed!

  3. #103
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    I've been hearing a lot lately about low BB height and pedal strikes. That leads me to my question: What is the ideal BB height, or BB drop?

    I'm sure somebody has the answer as it seems that any newer bike is too low.

    My 3 bikes are very similar in height and I don't seem to experience pedal strikes as often as what the internet says I should be experiencing. I'd like to hear what the ideal height is so I can compare to what my bikes are set up as.

  4. #104
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    Quote Originally Posted by Forest Rider View Post
    I've been hearing a lot lately about low BB height and pedal strikes. That leads me to my question: What is the ideal BB height, or BB drop?
    There is no one answer for everyone everywhere. The answer will depend where you ride and how you ride.
    Safe riding,

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  5. #105
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    Does BB height matter to you?

    Quote Originally Posted by Forest Rider View Post
    I've been hearing a lot lately about low BB height and pedal strikes. That leads me to my question: What is the ideal BB height, or BB drop?

    I'm sure somebody has the answer as it seems that any newer bike is too low.

    My 3 bikes are very similar in height and I don't seem to experience pedal strikes as often as what the internet says I should be experiencing. I'd like to hear what the ideal height is so I can compare to what my bikes are set up as.
    What do you mean? For every type of bike, person, riding style and terrain? There’s no such thing. What makes geometry ideal is you, does it work for you? Seems you may have found that already, what’s your height or more accurately what’s your drop and preferred tire diameter? B.B. drop not only affects pedal clearance it has other implications to the geometry of a bike, it will affect stack height, it will impact the rear centre and so forth. Bike geometry is extremely complex add in the dynamic factors of movement and yikes...

  6. #106
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    Yeah, I know all that.

    But with as many complaints that state "I'm tired of low BB height", there has to have been some change over time that is now a problem -one would think.

    BB drop is what is critical as the height, otherwise, is only affected by tire size.

    I figured that of all the people saying the BB height is too low, they must have a comparison.
    Right?

  7. #107
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    Quote Originally Posted by Forest Rider View Post
    I've been hearing a lot lately about low BB height and pedal strikes. That leads me to my question: What is the ideal BB height, or BB drop?

    I'm sure somebody has the answer as it seems that any newer bike is too low.

    My 3 bikes are very similar in height and I don't seem to experience pedal strikes as often as what the internet says I should be experiencing. I'd like to hear what the ideal height is so I can compare to what my bikes are set up as.
    I agree with the previous 2 commenters, but this is something i've explored a bit as a hobbyist frame builder, so at least i can offer up some numbers and you can do what you want with them. In general, i'll tolerate a lower BB than most riders will, but i find the BB height on my '15 transition patrol to be low enough that it's a performance handicap.


    For 130-150mm travel AM hardtails-

    -290mm static height is the lowest i'll go with 175mm cranks and clipless pedals, ridden primarily in mountainous forested terrain.
    -305mm static height is a good place to start with 175mm cranks and clipless, for a bike that will be ridden on unknown terrain and for an unknown individual.
    -Add 5-10mm to BB height if the rider will be using flat pedals.
    -Add/subtract BB height if the cranks are longer/shorter than 175mm.
    -Trails in flatter regions tend to favor higher BB heights than trails where you're typically on steeps.
    -Add 5-10mm for riders who like to pedal on descents.


    It gets more complicated with FS because variable shock leverage ratio and compression tune can affect how high the BB feels subjectively.




    WRT BB drop- drop describes a frame, height describes a bicycle. At least for me, drop is important when designing a frame, but height is what matters once the wheels are installed.
    "Things that are complex are not useful, Things that are useful are simple."
    Mikhail Kalashnikov

  8. #108
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    Thanks for taking the time to respond, but I guess the point was missed.
    Oh well.

  9. #109
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    Quote Originally Posted by Forest Rider View Post
    Thanks for taking the time to respond, but I guess the point was missed.
    Oh well.
    Failure on your part to adequately describe what you want to know, frame the question so it can be answered, or ask a question that can be answered by your audience. there isn't a one-size-fits-all answer to your question; if someone plugged in a number that's evidence they don't understand the details.
    "Things that are complex are not useful, Things that are useful are simple."
    Mikhail Kalashnikov

  10. #110
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    the more skilled I get, the less pedal strikes I get, on the same bike and terrain.

  11. #111
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    Quote Originally Posted by Forest Rider View Post
    Thanks for taking the time to respond, but I guess the point was missed.
    Oh well.
    The problem is that you are asking a question that doesn’t have a real answer. It depends on terrain, riding style, skill, personal preferences, type of bike, etc.... I think you got a thoughtful response that starts to show why there is no ‘correct’ answer to your question.

  12. #112
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    Quote Originally Posted by Forest Rider View Post
    I figured that of all the people saying the BB height is too low, they must have a comparison.
    Right?
    If you look, most bikes over last few years are in the mid to low 13" BB range. For me that is too low and think 14" would be a good compromise BB height for most tail bikes.

    My 130mm trail/all mnt bike has 13.9" BB height with it slightly long shocked and a 10mm longer fork. Still get occasional strikes but find this to be acceptable height and would not want it any lower.

    My 110mm XC/light trail bike sits at 13.5" and rarely get any strikes. But I ride/climb mostly smoother trails with it.

  13. #113
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    As low as possible

  14. #114
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    For me, my 2015 Trek Remedy 9.9 29er BB height is LOVELY. If I pedal strike, I'm stupid, or made a mistake. I can live with that all day long. I have a 160 fox36 fork installed.

    My actual measured bb height, floor to center, 346mm.

    I also have a 2018 KTM Kapoho, 27.5+. 130mm fork. Actual BB height, floor to center, 305mm.
    Lets put the 29er wheels on it, and the BB goes to 315. Thats a HUGE diffrence.
    On the Kapoho, I pedal strike ALL THE TIME. One ride, I counted 25 pedal strikes in the first 4 miles.
    My Remedy, 2 - and they were all stupid mistakes on my part. My KTM Scarp XC bike, I counted 3 pedal strikes on the same course. I think I just want a BB height OVER 330mm.
    "Go soothingly in the grease mud, as there lurks the skid demon"

  15. #115
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    The issue nobody is talking about is wheelbase. Longer distance between wheels means more pedal strikes in many situations. Most of my pedal strikes happen when rolling over things, which has increased with longer wheelbases.

  16. #116
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    Quote Originally Posted by DethWshBkr View Post
    My actual measured bb height, floor to center, 346mm.
    Nice. That's a reasonable height.
    Safe riding,

    Vik
    www.vikapproved.com

  17. #117
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    Moderators:

    Due to the recent and overwhelming interest in the discussion of bottom bracket height, please create a "Bottom Bracket Height" sub-forum. Thank you.

  18. #118
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    Quote Originally Posted by In2falling View Post
    If you look, most bikes over last few years are in the mid to low 13" BB range. For me that is too low and think 14" would be a good compromise BB height for most tail bikes.

    My 130mm trail/all mnt bike has 13.9" BB height with it slightly long shocked and a 10mm longer fork. Still get occasional strikes but find this to be acceptable height and would not want it any lower.

    My 110mm XC/light trail bike sits at 13.5" and rarely get any strikes. But I ride/climb mostly smoother trails with it.
    I have a custom 29er hardtail with a 13.4" bottom bracket and it is a great rock crawling bike

  19. #119
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    The next industry innovation for pedal strikes - lift kits for bikes.
    Riding Washington State singletrack since 1986

  20. #120
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    I like low BB's cause I don't want to dumb down the climbs. I think big BB height bikes are just to make it easier for new riders to monster truck through the climbs without ever learning how to not pedal strike. /s

  21. #121
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    Quote Originally Posted by jeremy3220 View Post
    I like low BB's cause I don't want to dumb down the climbs. I think big BB height bikes are just to make it easier for new riders to monster truck through the climbs without ever learning how to not pedal strike. /s
    Which is why you ride a 26" bike too?? Rigid?? Or is it a unicycle??

    I respect people's opinions, but I don't think BB height is a 'dumbing it down' issue. Or, maybe the lower bottom bracket is dumbing down cornering skills, and 'skilled riders' should stick with higher bottom brackets? Different strokes for different folks I say... Ride what you like, but let's not be insulting about the whole thing.

    It seems like everything is trending long and low, so I guess you win. But its nice to see a vocal minority (I'm assuming) that have the same issues with the newer geometry trends that I do.

  22. #122
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    Quote Originally Posted by Ob917 View Post
    As low as possible
    So if you use 175 mm cranks, a 180 mm BB height would be about as low as you could go?
    I Pity The Fool That Can't Ride A Bike Without A Dropper!!

  23. #123
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    Quote Originally Posted by SqueakyWheel73 View Post
    Which is why you ride a 26" bike too??
    Too easy to 360.

    Rigid??
    Too easy to ride skateparks.


    Or is it a unicycle??
    Too easy to start a career as a clown.

  24. #124
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    Quote Originally Posted by mountainbiker24 View Post
    The issue nobody is talking about is wheelbase. Longer distance between wheels means more pedal strikes in many situations. Most of my pedal strikes happen when rolling over things, which has increased with longer wheelbases.
    Exactly my thought over the years as I watched bikes get lower and longer. Just like off roading... a full size truck with a 6" lift and 36" tires isn't as capable getting over certain stuff as a Jeep with no lift and 29" wheels. In that world, we call it high centering.

    But realistically, we're not talking about actually high centering our bikes. We're talking about pedals touching terra firma. Each pedal is level with, or further from, the ground 50% of the time than the bottom bracket is. So, where is the issue really. Like others have said, don't have your pedal in the wrong position at the wrong time. For the most part, we're talking, what, an inch or less difference between what is considered high and low BB' on modern geometry on like for like purpose bikes. Comparing taller/shorter bikes to longer/lower bikes is like my truck/Jeep comparison. Different tools for different situations.

    That inch or less in BB height won't make up for laziness in pedal position. I (anyone) can just as easily strike pedals on a BB height of 13.75" as 12.75" if pedals aren't where they should be. Admittedly, I went through short learning curves to adjust, or plan for, pedal position as bikes got lower. But I'm OK with a lower BB in exchange for lower COG. Overall, a much better design, in my opinion. But that also depends on the type of riding.

    My most recent change in daily rides took me from a BB of 13.6 (345mm) to a 13" (330mm). Yeah, only ~.5", but I struck pedals on a the first couple of rides. Never since. And it honestly had more to do with timing the pawl engagement than BB height. The new bike has a wider engagement gap that I needed to get used to.

    Anyway... this is a really old and long thread, so I'm know all this noise has been said before... probably by me even (or I changed my mind along the way ). So, sorry about the re-hash.
    You didn't quit riding because you're old, you're old because you quit riding.

  25. #125
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    What I noticed, is TRAILS are being stupider.
    Here new ones made are narrow, off camber smooth stuff.

    Explain to me how I am supposed to not have a pedal strike when I MUST pedal uphill. Nearly every single pedal stroke would need to be ratcheted.
    Yep, on the tech stuff, I rarely pedal strike. I can move around the bike, ratchet, and push over things.
    When I'm grinding up a 1st gear steep off camber climb, I can't stop pedaling and ratchet to prevent a pedal strike from the one pedal hitting the uphill section.
    "Go soothingly in the grease mud, as there lurks the skid demon"

  26. #126
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    Crank length is more of an issue ^^

    'Born to ride!'
    "Mountain biking: the under-rated and drug-free antidepressant"

  27. #127
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    Quote Originally Posted by DethWshBkr View Post
    What I noticed, is TRAILS are being stupider.
    Here new ones made are narrow, off camber smooth stuff.

    Explain to me how I am supposed to not have a pedal strike when I MUST pedal uphill. Nearly every single pedal stroke would need to be ratcheted.
    Yep, on the tech stuff, I rarely pedal strike. I can move around the bike, ratchet, and push over things.
    When I'm grinding up a 1st gear steep off camber climb, I can't stop pedaling and ratchet to prevent a pedal strike from the one pedal hitting the uphill section.
    What we run into around here are older trails that have eroded into deep narrow ruts, making constant pedaling difficult. But in those cases, an inch difference in BB height doesn't make a difference.
    You didn't quit riding because you're old, you're old because you quit riding.

  28. #128
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    I've analyzed BB height for every bike I've considered buying for the past 20 years. This began after my introduction to the Cannondale M800 Beast of the East bike a friend of mine owned back in the 90s. I witnessed the advantages of a high BB.

    But for some terrain you don't need a high BB. If you ride on the east coast, you probably need a taller BB height. If your trails are smoother, maybe not so much.

    I don't believe that changing your riding style or shorter crank arms are the answers. That might show some success in the short run. However, after hour three on a gnarly trail, it's tough to constantly back-pedal or adjust pedal cadences. The same goes for chainring height which does not change with shorter crank arms.

    My concern is that it's getting harder to find bikes with heigher BBs. It's like the vast majority of the manufacturers saw a low bike trend, and followed that trend (with all of their bike lines) right over a cliff. And now, here we are, wondering why we can't get bikes with higher BBs.

  29. #129
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    So, since for the time being, we have the BB heights we have. What do you do to help when you need that extra (whopping) 1/4" to 1/2" of clearance?

    Me personally, if I know I'm riding a rock garden known for potential strikes (and I remember to think about it), I adjust my front and rear sag to 25% from its normal 30%. That adds just a tad more height with me on the bike at rest. It also resists, ever so slightly, suspension compression, which also keeps the BB just a smidgen higher. Does that really help? Doubt it. But it makes me feel better. Perception is reality!
    You didn't quit riding because you're old, you're old because you quit riding.

  30. #130
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    My 29 hardtail has 64mm of drop for a 308mm BB height. The low BB is a non issue for me with 175mm cranks and big Kona WW2 pedals. When I put on the 650B+ wheels the BB drops to 299mm and then it's an issue, so I have 165mm cranks for that. I'm very happy that the BB isn't any higher because of the handling benefits. I've had high BB bike in the past, and have to desire to go back.
    I got some bad ideas in my head.

  31. #131
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    Quote Originally Posted by Travis Bickle View Post
    My 29 hardtail has 64mm of drop for a 308mm BB height. The low BB is a non issue for me with 175mm cranks and big Kona WW2 pedals. When I put on the 650B+ wheels the BB drops to 299mm and then it's an issue, so I have 165mm cranks for that. I'm very happy that the BB isn't any higher because of the handling benefits. I've had high BB bike in the past, and have to desire to go back.
    I guess it's to be expected that a hardtail can manage a lower static BB height, but the difference between my rootdown at 320mm and 175mm cranks to my Bronson with 341mm and 165mm cranks is crazy.
    When factoring in the crank length I in theory have 30mm more clearance (pre-sag of course), but even with an extra 30mm pre sag, the Bronson feels painfully low and the rootdown is totally fine, could stand to be lower, even.

    I don't think think my riding style and/or weight suit the Bronson's suspension curve very well and the bike tend to ride too deep units travel. Obviously I can run less sag and/or more low speed compression and it's better in terms of pedal strikes, but then it doesn't ride well.

    So all that to say static BB height is obviously just one piece of the overall picture. The dynamic ride height based on suspension setup and characteristics also play a big part.

    I kinda wish BB height (actually, all geometry numbers, really) was provided at sag. A 160mm bike obviously has a much higher static BB than a 120mm bike or a hardtail, but once sagged may be lower.

    As to the original question, yes I am sensitive to it. I clipped a pedal on my Bronson going about 40kmhr on a fairly tame trail that was bench cut and slightly off camber, so one side of the trail was "higher" than the other. Pedal on the high side hit a root and stopped the bike dead, but my body of course keep going (flying). Completely unexpected. Broken ribs. No fun.

    So now BB height really affects my confidence. If I feel like my pedals are "exposed" on a high speed descent I get quite nervous. I'm not sure I will totally trust my Bronson again after that crash (was about 6 months ago now). Higher BB is definitely harder in bermed corners but I prefer having to work on cornering technique than trying to micromanage keeping my pedals away from the trail at high speed to avoid dying. If I rode mostly flowing bike park type stuff I'm sure it wouldn't matter as much, or maybe if I had more skill. As it is I will take a higher BB and just put more effort into keeping myself low on the bike when needed.

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