Fit / adjustment to avoid numbness - Advice sought
 

I have (until I convince myself that I merit something more roadish) a 2010 Trek Navigator 2.0. Yeah, this is definitely a case of buying the first bike (in years) to learn what I should get for the second one. :twitchy: It has a 21" frame, which is the seat tube length if I understand correctly. I'm 6' 2" and all in all the bike fits OK, even if it is a very upright geometry. I have the seat properly raised, etc. (saddle height is about 48" IIRC).

Still, I tend to go numb after a fairly short while. When I do, I realize I've slid forward and am no longer sitting on my sit bones. If I slide back, I'm comfortable and the numbness abates. However, I don't stay there without concious attention and effort. This bike has an adjustable stem and I could lower it (which helps a little aerodynamically), but that would probably make the sliding even worse. The saddle is already tilted back a little, with the nose higher than the back.

Is this most likely due to poor adjustment / fit, saddle type or what? It's definitely a comfort bike style saddle, but when I'm up on it properly, it's OK. I wear riding shorts with a chamois, BTW. The frame has a 68 degree seat tube angle and I wonder if I'm just too far back from the handlebars and need something with a more vertical seat tube... ? I guess I could raise the stem a bit, but the last thing I want is to be even more upright.

It may be that I just need to bite the bullet and move on to a road bike instead of trying to make this one do something it's perhaps not designed to do?

Or not? Any ideas?

Thanks.

http://bikeforums.net/attachment.php...hmentid=221022

Ah, you didn't say what is going numb. It could be your hands...

If the saddle can be adjusted fore and aft on the rails, consider sliding it forward a bit. It sounds like sitting further back on the saddle works for you but for some reason you end up moving forward on it. Maybe you're just having too reach to far forward.

The other possibility is that the saddle is tilted forward so that you slide forward on it and have to continually push yourself backwards with your hands.

Finally, consider that if the saddle is tilted to far back it puts pressure on your prostrate. Not good, of course. Make the saddle level first.

Sorry, as they say in Little League, "My bad". It's my groin that goes numb, not my hands. And now that you mention it, I don't know why I haven't slid the saddle more forward. Actually, I did slide it some quite a while back, but maybe I need more.

Could be, but when I sit properly on it, all is OK. I'll have to see.

Darn it... I was hoping to be told that all would be cured with a simple application of N+1. :D

I am of the understanding that saddles should be level. But, then again, what do I know? :)

Buy a new bike with a level saddle.

OK - There, I've been told, now I have to do it... right? ;)

Actually, the saddle is almost level with only a slight tilt, but I may have made the wrong adjustment to prevent sliding. I'll have to level and move it forward before my next ride and see how that works.

Thanks.

this.

The saddle should be close to level. Casual saddles on casual bikes like the Nav can be tilted up in front just a bit to keep you from sliding forward. This is because the riding position is upright and the saddle is soft.

Your coincidence of crotch numbness and the urge to slide forward indicate to me that your saddle is too high. Leave the setback where it is and just lower it a bit until your butt is happy settling back in the pocket. Then call back and tell us if your crotch is still numb.

Get a road bike and start with a level saddle, then make adjustments

That will fix the problem for sure only if the +1 is a recumbent bike.

Your problem can is not simple and can NOT be solved online with simple advice from well meaning people who know almost nothing about your body and riding style and in many cases, very little about bike fitting. Yes, someone's suggestion may help, but if it does it will be coincidence.

Be aware that a certain amount of numbness is unfortunately common. It's not the most pleasant aspect of biking and it's not good for you, but it is likely to be there. Pedaling in the standing position for a minute or so every 10 or 12 usually helps relieve it. Having a bike that fits your properly (and I mean much more than just size by this) and a saddle that conforms to your anatomy also help but you may never get rid of all of it.

As to having a bike that fits you properly, every one is unique. Different angles, different amounts of reach, different saddles work better for different people and if you try solving your problem by trial and error based on amateur advice you may suffer a lot and maybe even do some permanent damage to your nerves in the groin area before you minimize your discomfort to the greatest possible degree. Also, what works best for you on one kind of bike (e.g. hybrid) may not be best for you on a different type. (e.g. road or Mt.)

Some lucky people just buy a bike off the shelf and it never hurts. My wife for example, who is usually very fussy about her bikes fell in love with a Specialized Dolce last year and never had to change a thing on it. She has 3 custom built bikes, but the Dolce is her favorite. However, many of the multitudes of bikes gathering dust in garages are there because of problems like the one you describe.

Whether you want to modify the bike you have or buy a new one, the best advice I can give you is to consult a professional bike fitter in your area. Bike fitting is part science and part art. All bike fitters take specific measurements. Some use simple tools, some use computerized instruments and lasers, some use adjustable machines that simulate bikes, but all of the good ones have learned their trade over considerable time. If you enjoy biking other than the numbness, give your problem the attention it deserves. It will take anywhere from an hour to 1/2 a day and cost you a hundred or two or even more, but if you like cycling you cannot make a better investment.

One more piece of info. Most bike fitters are also mechanics and work as shop employees. Many of the shops where they work will provide fitting services free of charge if you buy a bike from them. It's hardly worth buying a new bike just to get fitted for free, but if you are looking for one anyway, why not do business with a shop that has a reputation for good fitting?

Here's a link to a short article on the subject.

http://www.examiner.com/cycling-in-n...orth-the-money

As an addendum, some people including me find it better to have the saddle fractionally nose-up rather than level. This ensures that I never slide forward and thus keep my weight on the sit bones, where it should be, rather than the soft tissue. So experiment. You'll find that tiny adjustments will make big differences.

I had similar problems with the stock saddle that came with my Trek 7300. The issue was the dip in the center of the saddle and the wide flare of width in the back. A Brooks B17 solved that.

I'm not an expert on the subject by any means, but my philosophy on saddles is this: The more saddle you have under you the more ass its gonna hurt...aka numb private parts etc. Get a smaller saddle with a split down the middle that insures blood flow to the tallywhacker.

With the saddle at its current height my leg is almost but not quite straight with the ball of my foot on the pedal at BDC. I had it a bit lower, but my knees know the difference.


That's about how it is now, but I'll experiement by leveling it then moving it forward to see if that makes a difference It will probably be next Saturday before my next chance to ride long enough to tell, though.


Given the level of general experience and expertise of this group, I would put it above the level of coincidence. I agree - There's no way anyone can accurately diagnose a complete solution online, but the folks here have a lot of miles under their collective jerseys and the various suggestions and pointers are indeed very helpful. I've had this bike since April 2010 and have pretty much everything else dialed in except for this crotch numbness over time. I'll just keep plugging away on it.

As far as LBS and such, there's one locally, another 75 miles away and the rest are 90/100+ miles. I'm glad for the LBS and will definitely use their services when it's time to look at a new bike.


That could be it, too. I'll have to determine how much (if any) I'm willing to put into a bike that I don't want to keep long term.


Good suggestions all. I'll see what I can discover.

Thanks! :thumb:

Just keep in mind that a good saddle (Brooks, for example) is transferrable from bike to bike.

There are a lot of variables - saddle, saddle tilt, fore and aft adjustments, height of seatpost, height of saddle vs. height of bars, amount of weight on butt vs. hands and arms, (what did I forget?)

I've fought numb-butt for decades. My "solutions" include a Brooks saddle, as well as adjusting everything else repeatedly and minimally to arrive at a comfortable setup. However, nothing has completely solved the problem. The "final solution" for me is to get off the bike when my butt starts to hurt. 10-15 minutes off the saddle can give me a good hour pain-free when I get back on.

Some of it is pure opinion, and some of it is experience. I don't believe some numbness is to be accepted. It occurs for enough people to be formally "the norm," meaning most people have some, but I think it can be beaten.

First thing is to start with your saddle at the standard height. I won't say it's "correct" or "normal," because most of us make small adjustments away from this position. One standard starting point is to measure your cycling inseam of pubic bone height when barefoot (there used to be good instructions on this at http://www.rivbike.com/kb_results.asp?ID=39. Measure in millimeters if you have a metric tape, or to the nearest sixteenth of an inch. The precision is important. Once you have this number multiply it by 0.883. With your saddle level, set you saddle height (measured from the center of the bottom bracket to the top of the saddle in line with the seat tube) to this value. You'll probably find some good reasons to deviate from this setting, but it's normal to see if it works. For most people this setting also gets your knee bend and range of motion into the correct range.

Then get on the bike sitting as comfortably as you can and have a helper hold you steady, or rig up a prop of some sort. With your pedal forward, drop a plumb line from the front of your knee. It should pass just in front of the end of the crank, or up to 2 cm (about 3/4") behind it. Non-competitive riders (we know who we aren't) usually do better with the knee toward the back of this range. If you set it at the forward edge of this zone, it's called Knee Over Pedal Spindle, or KOPS. Usually those four letters start a discussion. Move your butt forward or back ward until your knee is in your chosen position, then get off, loosen the saddle-seatpost clamp, and slide the saddle fore or aft until it is able to hold you comfortably in this position. Some trial and error will be necessary. After you're satisfied with this adjustment and the saddle is again level, re-check the saddle height measuring to the same point as before. You may need to raise or lower the saddle a bit to accommodate the sliding forward or backward. If everything is secure, go for an easy ride and notice how it feels.

This is more or less the standard approach to saddle positioning. There's a lot of fine points to troubleshoot aches, pains, abrasions, numbnesses, et cetera. None of this is claimed to be what you or anyone needs, but it's the usual starting point. See how you do with this, as a starting point.

I think learning how to fit is a matter of getting the little bit of knowledge and then to see how tune yourself in, making small adjustments at a time.

Have you taken the bike back to where you purchased it, explained the problem, and asked the shop for help fitting the bike to you?

A professional fit can run upwards of $100, but for a hybrid, an experienced cyclist/sales person could probably do more for you (for near or free) by laying eyeballs on you, on your bike, than a forum full of internet "advisors."

Up until 2006 I rode Mountain bikes and it was pretty aggressive stuff aswell. In 2001 I had a Prostate problem and after surgery I had a saddle problem. This was down to the Surgery and a cure that worked for a while was a saddle with a cutout in it. Unfortunately- the surgery continued to throw a problem at me and it was severe butt Ache. But that cutout certainly did assist with the pain. So first suggestion is to look at the saddle. Is it far enough forward? 68 deg sounds like a very slack seatpost angle to me and you may have to bring the saddle forward to stop sliding forward. My MTB has a seatpost angle of 73 and the road bikes are 74.

And secondly- in 2006 I bought a road bike. Instant cure. May have been co-incidence but doubt it. I have thought about this and on a road bike the torso is more stretched out and the butt is in a different position to on a mountain bike. That completely different seating position kept me cycling and it seems all wrong

Have a suggestion and that is to go out on a ride and get Butt Ache but finish up at your LBS. Sit on a road bike that is approximately set up for you and see if you can feel the saddle. Could be like me that the different seating position will work. With the butt ache still there- you will know if it will work.

That's what I'm wondering, as well. Unfortunately by the time I get home from work there's no time to ride (long enough), and with the days getting shorter that's getting truer by the day. I'll check it this coming weekend.


Strangely enough, I don't really end up with a butt ache, per se, but my nether regions do go soundly asleep after a while. Standing for a few seconds then shifting back on the saddle awakens everything, at least.

I might have to work out the logistics of ending up at the (only local) LBS somehow... literally over the river and sorta through the woods. :) The "LBS" where I bought this bike is actually just a bike shoppette in the corner of a larger store and about 75 miles away. The local LBS is a bit closer.

Thanks.

If you're sliding toward the front of the saddle, either your saddle is too far back, the nose is tilted too far down, or the bars are either too low or too far forward. Or all of the above.

I suggested lowering the saddle to see if your butt settles back into the pocket of the saddle and you replied that you can't because it makes your knees hurt. I didn't say lower the saddle and pedal hard to make your knees hurt, I said lower the saddle to see if your butt doesn't settle into the back of the saddle where it should be. Getting comfortable on a bike is a trail and error process and sometimes you have to take one step back to move two steps forward.

Here's some other advice. Take the bike back to the shop where you bought it, tell the fitter or salesman what your problem is, have him watch you take a couple laps around the parking lot, and listen to his advice. That's his job. Getting comfortable on a comfort bike should not be difficult.

Let me back up and explain myself. First, the Navigator is a comfort bike. The frame has slack angles, it has long head tube that allows the bar to be set quite high, and the reach from the saddle to the handlebar is quite short. It has padded, sprung saddle that, while being mattress-like, is not the super-wide pillow of a cruiser. It has soft 26x2 tires.

I'm focusing on the fact that you're creeping to the nose of the saddle as the source of your discomfort. The widest part of a Navigator saddle is about one of the most comfortable places I know to seat my pelvic girdle, and for your perineum to be perched on the narrowest, least cushioned part of the saddle there must be a compelling reason. I'll run through the common ones.

I have to reach to far for the handlebar. This is most common with road bike riders where the rider's back as at a 30-60 degree angle, the back or neck feel overextended, breathing is cramped, the hamstrings are over-stretched, or the hands are getting numb. With the Navigator's short reach this seems unlikely to me, but you never know.

I am trying to push the pedals harder. New riders often try to get their weight over the pedal they're pushing, believing that the harder they push the faster they'll go. Bikes are designed for the rider to be balanced over the pedals and saddle with minimum input from the hands on the handlebar. Personally, I went through this phase when I was just starting out 39 years ago. Shoved the saddle as far forward as it would go, raised it til my knees stop hurting, and pushed around a big gear, finishing my pedal stroke by extending my ankles. And when I got off the bike my crotch hurt and my knees hurt so badly anyway, I had to stop riding for a few days.

The saddle is too high. I see this in many of the road riders on my Saturday morning rides. They creep to the front of the saddle to because their legs are telling them they want to be closer to the pedals. And then they'll tell me that some expensive fitter told them this is how high their saddles should be, and I'll say, just try it for a few days and see if the pain goes away. Sorry, that's only way you can test this. If you're worried about your knees, the only advice I can give is use lower gears and a lighter, more supple pedaling technique for the duration.

The saddle is tilted down in front and I'm sliding off. Many riders of road bikes do this deliberately to reduce pressure on the perineum, and that comes from the forward leaning angle of the torso of the road bike position. And then some riders slide into this position simply because the back of the saddle is too high for them to sit on. Still others like to push against the back of the saddle when they're pedaling hard. Not only is this uncomfortable, it puts pressure on the hands, wrists, shoulders, and an knees. The Navigator is upright and soft and made to be ridden with the body in balance over some point between the hips and feet.

There is something painful back there that I'm trying to avoid sitting on. If it's on the saddle, see a dealer for a new saddle. If it's not on the saddle, see a doctor.

So there you have it. What is compelling you to sit on the least comfortable part of your saddle? Only you can answer that.

The saddle could be too wide, or the back part of the saddle could be shaped wrong for the OP's anatomy.

Sitting on the nose of the saddle can cause penile numbness. Fix the reason why you are sliding forward and the numbness will decrease.