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The Open Road => Beginner's Garage => Topic started by: RBEmerson on April 13, 2017, 09:09:26 pm



Title: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 13, 2017, 09:09:26 pm
I was on a BMW F650GS loaner, zipping around a corner, and encountered a deep, big manhole cover. My general reaction to anything that's going to bang me around - train tracks, unavoidable potholes, etc. - is to stand up or at least get off the seat. In a turn and leaned over... oops, deep big manhole cover, and up I went. Good idea? Bad idea?

In general, the idea of standing up is to move the center of gravity lower - more stability. What about leaned over in a turn?


Title: Re: Big manhole cover - sit down, stand up
Post by: rajflyboy on April 13, 2017, 10:47:17 pm
Its my motto :

"When in doubt smoothly get on the throttle"


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 14, 2017, 09:56:02 am
Well, yeah, that will lift the front a bit.

The more I thought about the issue, more I'm inclined to think standing up wasn't a bad idea. Standing up drops the CG, so even if I'm leaning already, I shouldn't have a big problem with getting the bike over far enough for things to get exciting.

BTW, the thing was a near-crater. One of the all-time worst I've seen.


Title: Re: Big manhole cover - sit down, stand up
Post by: birdrunner on April 14, 2017, 01:30:42 pm

Well, yeah, that will lift the front a bit.

The more I thought about the issue, more I'm inclined to think standing up wasn't a bad idea. Standing up drops the CG, so even if I'm leaning already, I shouldn't have a big problem with getting the bike over far enough for things to get exciting.

BTW, the thing was a near-crater. One of the all-time worst I've seen.

Shouldn't standing UP  ----- RAISE  the centre of gravity.?


Title: Re: Big manhole cover - sit down, stand up
Post by: jay547 on April 14, 2017, 01:31:09 pm
Be sure to report it to the city/county/responsible authority before someone is injured. Report it as a safety hazard and it will more likely get taken care of.

Jay = person whom works for a city street department.


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 14, 2017, 01:36:45 pm

Be sure to report it to the city/county/responsible authority before someone is injured. Report it as a safety hazard and it will more likely get taken care of.

Jay = person whom works for a city street department.


Optimist. Boyertown borough has quite enough drains on their budget.


Title: Re: Big manhole cover - sit down, stand up
Post by: jay547 on April 14, 2017, 01:40:20 pm



Optimist. Boyertown borough has quite enough drains on their budget.


That's generally the case everywhere. I mostly handle sidewalk and wheelchair ramp complaints and requests. With the budget that I'm allotted, I'm only able to do about 10% of them.


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 14, 2017, 02:11:06 pm


Shouldn't standing UP  ----- RAISE  the centre of gravity.?


I know it's counter-intuitive, but CG drops because your weight is no longer on the saddle but on the pegs, which are lower than the saddle. Where you contact the bike is where your weight is applied. (Weight on the grips is a push because that weight probably doesn't change significantly from sitting to standing.)


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 14, 2017, 02:11:44 pm



That's generally the case everywhere. I mostly handle sidewalk and wheelchair ramp complaints and requests. With the budget that I'm allotted, I'm only able to do about 10% of them.
Keep doin' what you're doin', sounds like worthy work to me.  :)


Title: Re: Big manhole cover - sit down, stand up
Post by: R Doug on April 14, 2017, 03:13:18 pm
From the BMW Motorrad GS Off-Road Training l attended, standing on the pegs does not lower the CG.  


But, it does offer the following benefits (with #2 and #3 being the key reasons you at least lift your butt off the seat for bumps).

First:  The most important reason for standing up is increase your vision ahead on rough terrain. That allows you to avoid obstacles such as potholes, rocks or mud, or to pick a better path so you don’t end up in the deepest rut, or to see whether there are oncoming vehicles over the crest of a hill.

Second:  Your legs become “part of the suspension,” so a sudden and large bump doesn’t jolt you off the bike as your legs absorb some of the impact. Don't lock your knees!  



Third:  Standing eliminates the jostling of the bike from your body weight. If you hit a rock or momentarily lose traction and the bike kicks sideways, standing helps minimize that the bike moves, not you because you have better leverage to counter.  A rider sitting on a bike tends to overreact to every sideways movement of the bike. Standing up divorces you from all these minor movements so you aren’t worried by every buck and weave. It also allows the bike to do its own thing without the distributing influences of unnecessary and reactionary handlebar corrections.



Fourth: Standing can give you extra control over the bike with your feet.  Try standing up on your bike and concentrating on not putting any steering or counter-steering pressure on the handlebars.  Then move your right knee slightly forward. This puts pressure on the left footpeg. Notice what happens. The bike will swerve to the left.

Sitting down and putting pressure on the footpegs doesn’t have near as much effect as when you stand and put your whole body weight into a footpeg.  You can use this pressure on the footpegs for steering the bike, but also for adding traction when the tail is sliding out.  Place you weight on the footpeg on the side the rear wheel is sliding toward.

Steering with your feet also means less handlebar input is needed and less reliance on front wheel traction.


Title: Re: Big manhole cover - sit down, stand up
Post by: Windblown on April 14, 2017, 05:37:32 pm

I was on a BMW F650GS loaner, zipping around a corner, and encountered a deep, big manhole cover. My general reaction to anything that's going to bang me around - train tracks, unavoidable potholes, etc. - is to stand up or at least get off the seat. In a turn and leaned over... oops, deep big manhole cover, and up I went. Good idea? Bad idea?

In general, the idea of standing up is to move the center of gravity lower - more stability. What about leaned over in a turn?


I'd say your instinctive reaction was good.  There were a couple of turns at a local track that were quite bumpy at the apex and I found I could get over them a lot better/faster with my butt hovering just off the seat. The results had more to do with adding legs to the suspension equation rather than shifting CG IMHO, but regardless, it worked.


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 14, 2017, 06:26:27 pm
You hit on exactly why I went up. Even on my K1200RS I'll either give my quads and glutes a good workout, hovering just off the seat, or stand up as much I can. Beats the heck out of having my eyeballs rattled.  :D


Title: Re: Big manhole cover - sit down, stand up
Post by: rajflyboy on April 15, 2017, 07:00:22 am
Throttle baby.   It's all about staying in the throttle. Not upsetting the balance on each wheel  :thumbsup:


Title: Re: Big manhole cover - sit down, stand up
Post by: Acadian Rider on April 15, 2017, 08:42:25 am

From the BMW Motorrad GS Off-Road Training l attended, standing on the pegs does not lower the CG.  


But, it does offer the following benefits (with #2 and #3 being the key reasons you at least lift your butt off the seat for bumps).

First:  The most important reason for standing up is increase your vision ahead on rough terrain. That allows you to avoid obstacles such as potholes, rocks or mud, or to pick a better path so you don’t end up in the deepest rut, or to see whether there are oncoming vehicles over the crest of a hill.

Second:  Your legs become “part of the suspension,” so a sudden and large bump doesn’t jolt you off the bike as your legs absorb some of the impact. Don't lock your knees!  



Third:  Standing eliminates the jostling of the bike from your body weight. If you hit a rock or momentarily lose traction and the bike kicks sideways, standing helps minimize that the bike moves, not you because you have better leverage to counter.  A rider sitting on a bike tends to overreact to every sideways movement of the bike. Standing up divorces you from all these minor movements so you aren’t worried by every buck and weave. It also allows the bike to do its own thing without the distributing influences of unnecessary and reactionary handlebar corrections.



Fourth: Standing can give you extra control over the bike with your feet.  Try standing up on your bike and concentrating on not putting any steering or counter-steering pressure on the handlebars.  Then move your right knee slightly forward. This puts pressure on the left footpeg. Notice what happens. The bike will swerve to the left.

Sitting down and putting pressure on the footpegs doesn’t have near as much effect as when you stand and put your whole body weight into a footpeg.  You can use this pressure on the footpegs for steering the bike, but also for adding traction when the tail is sliding out.  Place you weight on the footpeg on the side the rear wheel is sliding toward.

Steering with your feet also means less handlebar input is needed and less reliance on front wheel traction.



Good stuff Doug.   :thumbsup:


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 15, 2017, 09:10:49 am

Throttle baby.   It's all about staying in the throttle. Not upsetting the balance on each wheel  :thumbsup:
No doubt about that.

Watching guys shut down the throttle entering a turn, for example, is cringe-worthy.


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 15, 2017, 11:34:43 am
Re: steering by weight shift, please see Bernt Spiegel's The Upper Half of the Motorcycle, pp. 43-44, and the Ecomobile shown on p.44.


Title: Re: Big manhole cover - sit down, stand up
Post by: Bounce on April 15, 2017, 01:34:22 pm
Also change tack and try to cross such things as upright and at as much of a right angle to the path of the thing as possible (easier to do on rr tracks than on a round manhole cover).

You do not want to give up what little traction you have on metal surfaces to maintain a lean angle.


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 15, 2017, 07:49:03 pm
Agreed on both points. For some reason, this crater surprised me although I go through the area fairly often. It was the part about being over, coping with a curve, and being partly on metal, that had me thinking. Further on, following the same road, there's a RR crossing. It's extremely rare for me to not be up when crossing this fun washboard.  :rolleyes:


Title: Re: Big manhole cover - sit down, stand up
Post by: rajflyboy on April 15, 2017, 08:49:15 pm

Agreed on both points. For some reason, this crater surprised me although I go through the area fairly often. It was the part about being over, coping with a curve, and being partly on metal, that had me thinking. Further on, following the same road, there's a RR crossing. It's extremely rare for me to not be up when crossing this fun washboard.  :rolleyes:


Well hey

I see you survived it!   You must have done something right.  :thumbsup:


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 16, 2017, 10:28:20 am
Or got away with it.

I think "got away with it" happens more often than we like. That is, the bike (as a system) wasn't pushed past its comfort point, even if someone's comfort point limit was getting close.

Back to the Upper Half (which can be fascinating in places and like attending a psych. lecture in other), there's a little bit about a rider who put a counter (the click-click kind) on his bike, and clicked it for every mistake he made. The point being that, of course, initially the count is astronomical, but the goal was to lower the count. Nice tool if one is honest about what happens. Otherwise... fooling yourself again.


Title: Re: Big manhole cover - sit down, stand up
Post by: rajflyboy on April 16, 2017, 09:42:57 pm
Oh yes

We all get away with many mistakes

For me it's so easy to let off the throttle in panic situations when many times the outcome will be much better by using more throttle


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 17, 2017, 12:07:30 pm
Or at least hold the throttle constant.

It comes back to "you ride like you train (practice)". Spiegel talks about this at great length and in great detail ( :rolleyes: ). Some of the reading takes motivation to stay with it, but at the end there should be some a solid understanding of what's happening and how to get to what is desired to happen.



Title: Re: Big manhole cover - sit down, stand up
Post by: rajflyboy on April 17, 2017, 09:24:08 pm

Or at least hold the throttle constant.

It comes back to "you ride like you train (practice)". Spiegel talks about this at great length and in great detail ( :rolleyes: ). Some of the reading takes motivation to stay with it, but at the end there should be some a solid understanding of what's happening and how to get to what is desired to happen.




Training certainly helped.  The Army requires motorcyclists take the ERC course at each duty station in which you are based.   That was well worth the time


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 18, 2017, 10:05:23 am
Well, given all the money the military put into your training, why wouldn't they try to protect the investment?  ;)


Title: Re: Big manhole cover - sit down, stand up
Post by: rajflyboy on April 18, 2017, 01:46:08 pm

Well, given all the money the military put into your training, why wouldn't they try to protect the investment?  ;)



True  :thumbsup:

And also a nice day off work to ride  :thumbsup:


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 19, 2017, 11:27:45 am
Too right.

I was out on a semi-work/semi-playtime trip yesterday. Charging around some of the corners with ...um... less than smooth paving, I spent more time putting weight on the pegs. Dunno if it really mattered, but the tires didn't feel like they were trying to depart the scene. Even when I rubbed my toes on the pavement (didn't plan on that).  :D


Title: Re: Big manhole cover - sit down, stand up
Post by: rajflyboy on April 20, 2017, 02:23:39 pm

Too right.

I was out on a semi-work/semi-playtime trip yesterday. Charging around some of the corners with ...um... less than smooth paving, I spent more time putting weight on the pegs. Dunno if it really mattered, but the tires didn't feel like they were trying to depart the scene. Even when I rubbed my toes on the pavement (didn't plan on that).  :D


I don't mind sliding the rear wheel a bit but I hate tucking the front wheel


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 20, 2017, 03:50:49 pm
You mean like this...


Title: Re: Big manhole cover - sit down, stand up
Post by: rajflyboy on April 20, 2017, 09:06:01 pm
Good one

Thanks  :thumbsup:


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 21, 2017, 09:20:15 am
Makes me wonder, though, why he didn't spend time learning to do a panic stop correctly. Woulda saved wear and tear on the bike, suit, and him. In descending order of importance.  :p

ADDED: I look at a traffic light turning sooner than expected as a chance to do a panic stop (if nobody's in back of me). Washboard, oil, wet paint... it's all there for the learning.  :)


Title: Re: Big manhole cover - sit down, stand up
Post by: rajflyboy on April 21, 2017, 02:01:52 pm
A lot of people don't understand the front brake on a motorcycle

I saw someone recently teaching a kid how to ride a bike.  He told his son to not use much front brake to stop the bike.  


Title: Re: Big manhole cover - sit down, stand up
Post by: RBEmerson on April 22, 2017, 08:58:19 am
Well, sure. Hit the front brake too hard and the bike will lift up in the back and might flip over.  :facepalm:

I went bicycle riding with a friend's kids; the bike had disk brakes. The kids kept saying "don't use the front brake or you'll flip over."  :facepalm:


Title: Re: Big manhole cover - sit down, stand up
Post by: Fun Dog on May 24, 2017, 11:35:18 am
Interesting situation with the surprise manhole cover and I'm glad you brought it up.  Good discussion too, but there are a couple of things that are important in this example that haven't been mentioned in the thread yet.

The first thing I didn't see was the simple fact that you should never be going so fast that you can't see a hazard like that coming up and have time to react to it.  That may seem obvious, but a lot of motorcyclists tend to roll on the fast side...and most times so fast that even the phenomenal brakes on a motorcycle can't help them when a road hazard pops up.  Double this for night riding where sight distance becomes an issue. Going fast on a motorcycle is an intracultural norm, so there tends to be a lot of peer pressure to ride fast when you've got a bike.  I understand that.  It's fun to really get on the throttle sometimes.  But you have to take responsibility for the fact that when you do get on the throttle, the road comes at you much faster and sometimes you don't have time to even spot (much less react to) a road hazard, particularly in corners where you are typically blind to what's coming up.  Best to go slow into corners, roll on the throttle a wee bit to keep the chassis stable and increase the contact patch, then, once you have a clear sight line to the exit and can see there's no trouble on the road surface, you can really get on the throttle and slingshot out of the turn.

The other thing I haven't seen mentioned yet is something I have first-hand experience with.  I was approaching a speed bump in a parking lot and going all of 5 mph at the time.  I decided to stand up on the bike to help with shock absorption over the bump.  You know what happened?  Take a guess...

...time's up!  I whacked open the throttle and almost threw myself off the back of the bike :facepalm:.  The difference between standing up on a motorcycle and a bicycle is that a bicycle doesn't penalize you for applying leverage force to the right grip to help you stand up.  If you're not aware that you're applying back-force to both motorcycle grips to help yourself stand up, you can easily whack open the throttle and you know the rest.  When you stand up on a motorcycle, if you're not careful of the pressure you're applying to the throttle in your right hand, you might wind up off the bike and on your ass. :eek:


Title: Re: Big manhole cover - sit down, stand up
Post by: Pat S. on May 24, 2017, 08:45:52 pm
Raise over the seat to use your legs as shock absorbers and keep suspension from bottoming. Avoid hitting it if possible, swerving left or right to avoid it. Look where you want to go not at what you're trying to avoid. You will go where you look.


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