Bicycle thread

[skibum69]

Originally Posted by Oznerol

A couple of times I've had good luck with very carefully detaching the hose at the lever, cutting it, and re-attaching it without introducing significant air into the system. No bleed required.

Race report?

hahaha, the bike is great, I however am not. Too much beer on Friday and trying to get back on regular sleep after working nights for a couple of weeks. I suffered. But fun and the highest turnout ever for an XC race here.

yeah I know about the brakes, like I said-too lazy. We only finished it 15 min before the shop closed yesterday so I could ride it today.

[Mercury264]

Day of firsts on Saturday:

1. First ever puncture on a bicycle - yep, really.
2. First ever time I fell over while still clipped in. Why ? See 1

Tire just went flat (turns out the base of the valve stem ripped) and I was so engrossed in that I forget to unclip...oh shit, why isn't my foot coming out Bang, down I went...

To compound that, I then screwed up my spare as I inflated it Had to get recovered so I only did 3 miles. I am thinking of carrying some CO2 cannisters as well as my pump - I friggin hate pumping tires up with it.

Weather here in New England has been atrocious the past month or so - I am seriously thinking of a. buying a mtn bike or b. breaking out my rollers again or c. all of the above.

[mac62]

OK, dumb question: went looking at bikes today at my LBS, haven't ridden seriously in 20 yrs and what do I find? Single speed, fixed gear bikes are all the rage. WTF? When did this happen? More importantly, WHY did this happen? Have you seen the price of these things? What's next, coaster brakes and fucking banana seats?

[Oznerol]

Rainy weekend here (after a rainy week), so I'm jonesing hard for a ride. I actually did 90 minutes on the trainer earlier this week.

OTOH, I finally executed on some long-planned upgrades for my 'bike garage'. The big one was setting up hooks so that I can wall-mount 4 bikes.



The hooks are staggered so that I can get the bikes closer together without the handlebars interfering. It works really well. I already had a couple of hooks, but the hardware store had some much better ones -- huge, so it's easy to get fat MTB tires in and out.

Also got some shelving and finally went through the pile of random parts and junked a lot of junk, pushed a lot of near-junk into basement storage, and organized the rest.

Also did a ton of overdue bike maintenance. The new stand makes it way less troublesome.

[sixer]

Originally Posted by mac62

OK, dumb question: went looking at bikes today at my LBS, haven't ridden seriously in 20 yrs and what do I find? Single speed, fixed gear bikes are all the rage. WTF? When did this happen? More importantly, WHY did this happen? Have you seen the price of these things? What's next, coaster brakes and fucking banana seats?

I love how simple mine is. I find riding SS you just ride, no thinking about gear changes etc. When you come to a hill you just stand and mash away. I know my legs are stronger then if I was riding a geared bike. Maybe we're all masochist's

[sixer]

Oznerol,

Nice setup. I tried a similar setup in my garage but I didn't like how the hook rested on the spoke/nipple. It's funny I think that would create stress on the spokes coming from a guy who weighs 266. Right now I've got a big garage that I have plenty of room for bikes. Thats going to change, so I might be trying out the hooks again.

[playzNmud]

TECHNICAL QUESTION:

I may not have enough information at hand for this question but I am going to ask anyway.


I am having all sorts of issues (front shock) dialing it in and now at a total loss of what to do.

on my MTB, I have replaced the front fork with a SID

I have NO responsiveness from it....on ANY turn, off camber and especially any downhill turns.. the front end is pushing hard.. NOT compressing at all.. okay.. I know enough to try and soften the compression... did that... and adjusted the rebound... still pushes... and now pops me off the bike (literally). The front end hit going down a very technical section of BIG rocks.. punched in and would not come back... over the bars I went (HARD)

I weigh approximately 103lbs, the shock now has 80/80 in the top and bottom of the fork....

okay, I am going to stop with my rambling here now...

in this adjustment.. what should I adjust first?? the air (in the top tube or bottom tube, should they remain equal, spring tension or mess with the oil compression.... see this shock has air adjustment on the left side and the oil is on the right.... if THIS makes any sense what-so-ever!

thanks.

[Askel]

Originally Posted by mac62

OK, dumb question: went looking at bikes today at my LBS, haven't ridden seriously in 20 yrs and what do I find? Single speed, fixed gear bikes are all the rage. WTF? When did this happen? More importantly, WHY did this happen? Have you seen the price of these things? What's next, coaster brakes and fucking banana seats?

Us kids think they're cool. Can't speak for the fixie thing, but SS 29ers are a hell of a lot of fun.

And sorry Playz, maybe if you gain a hundred pounds, I might be able to offer some useful suspension advice. Although, it does sound as if you have the same problem I do- working on the edges of the design parameters for suspension components. I never like air springs as at my weight, you have to pump them up so much to keep them from bottoming that they really lose their small bump compliance.

[DoctorIt]

Originally Posted by playzNmud

TECHNICAL QUESTION:

I may not have enough information at hand for this question but I am going to ask anyway.


I am having all sorts of issues (front shock) dialing it in and now at a total loss of what to do.

on my MTB, I have replaced the front fork with a SID

I have NO responsiveness from it....on ANY turn, off camber and especially any downhill turns.. the front end is pushing hard.. NOT compressing at all.. okay.. I know enough to try and soften the compression... did that... and adjusted the rebound... still pushes... and now pops me off the bike (literally). The front end hit going down a very technical section of BIG rocks.. punched in and would not come back... over the bars I went (HARD)

I weigh approximately 103lbs, the shock now has 80/80 in the top and bottom of the fork....

okay, I am going to stop with my rambling here now...

in this adjustment.. what should I adjust first?? the air (in the top tube or bottom tube, should they remain equal, spring tension or mess with the oil compression.... see this shock has air adjustment on the left side and the oil is on the right.... if THIS makes any sense what-so-ever!

thanks.

This doesn't make any sense... exactly what fork do you have? If I can find the tech manual online, I can be of help. I'm actually not familiar with the SID, in that you say you can pump air in the top AND bottom of the fork leg that controls preload?!

Just off the cuff, 80psi sounds just a little high for someone your weight, and all the symptoms point to still too much preload. Air shocks are actually very easy. Don't bother messing with the oil side (damping) until you have the preload set right.


EDIT: ok, went to the RockShox website - the 80/80 spec is for "<120 lb rider". You can most definitely go lower, like 70/70, maybe even 65/65. Do you know how to check your sag? That is the easiest way to set preload/air pressure. Get a zip-tie, put it around your fork slider, hop on the bike, bounce it a couple times, let it rebound and just sit on it with your weight. Slide the zip-tie down all the way on the slider and carefully dismount the bike. The sag should be roughly 25% of the total travel of the fork, maybe a bit less for a stiffer/short travel XC racing fork (on my 4.5" travel Fox Float, I run 1.125" of sag).

I'm still not really getting the positive/negative spring. Seems like more complication than you need in an air-spring XC fork.

[DoctorIt]

Originally Posted by sixer

Oznerol,

Nice setup. I tried a similar setup in my garage but I didn't like how the hook rested on the spoke/nipple.

Unless you bought your bike straight out of a box, or it was one of the few bikes out on the racks in the shop, 80% of bikes spend considerable time on a hook. Maybe the bigger newer shops can display more of their bikes, but at my shop, typical little hole in the wall, we can fit maybe, just maybe 30 bikes upstairs in the tiny shop, then we have more sizes/colors hanging from hooks in the rafters down in the basement (probably on the order of 50 more bikes down there).

That's beside the point - I've never seen any damage come to a typical bike hanging off its own modern wheel, they're far too strong for that.

[Javarilla]

Originally Posted by Askel

Us kids think they're cool. Can't speak for the fixie thing, but SS 29ers are a hell of a lot of fun.

My bikes that need to work and my bikes that need to go fast have gears.

All my 'fun' bikes are singles or fixies. They don't need to be fast.

The singles split the need to race everything on the trail out of your soul...

A fixie feels good because it's a direct connection to the physics of the universe...

[playzNmud]

Originally Posted by DoctorIt

This doesn't make any sense... exactly what fork do you have? If I can find the tech manual online, I can be of help. I'm actually not familiar with the SID, in that you say you can pump air in the top AND bottom of the fork leg that controls preload?!

Just off the cuff, 80psi sounds just a little high for someone your weight, and all the symptoms point to still too much preload. Air shocks are actually very easy. Don't bother messing with the oil side (damping) until you have the preload set right.


EDIT: ok, went to the RockShox website - the 80/80 spec is for "<120 lb rider". You can most definitely go lower, like 70/70, maybe even 65/65. Do you know how to check your sag? That is the easiest way to set preload/air pressure. Get a zip-tie, put it around your fork slider, hop on the bike, bounce it a couple times, let it rebound and just sit on it with your weight. Slide the zip-tie down all the way on the slider and carefully dismount the bike. The sag should be roughly 25% of the total travel of the fork, maybe a bit less for a stiffer/short travel XC racing fork (on my 4.5" travel Fox Float, I run 1.125" of sag).

I'm still not really getting the positive/negative spring. Seems like more complication than you need in an air-spring XC fork.

okay.. thanks. This is a starting point for me...and maybe I should do the same about searching for the specs for that particular shock. I was doing some reading on it last night and have found much negative feedback - mostly of the shock having too much flex

[Gummee!]

Originally Posted by Mercury264

Day of firsts on Saturday:

1. First ever puncture on a bicycle - yep, really.
2. First ever time I fell over while still clipped in. Why ? See 1

Tire just went flat (turns out the base of the valve stem ripped) and I was so engrossed in that I forget to unclip...oh shit, why isn't my foot coming out Bang, down I went...

To compound that, I then screwed up my spare as I inflated it Had to get recovered so I only did 3 miles. I am thinking of carrying some CO2 cannisters as well as my pump - I friggin hate pumping tires up with it.

Weather here in New England has been atrocious the past month or so - I am seriously thinking of a. buying a mtn bike or b. breaking out my rollers again or c. all of the above.

I usually use the CO2 to get most of the pressure then top off with a pump. That's assuming there's a pump around.

Not to , but

M

[Gummee!]

Originally Posted by playzNmud

okay.. thanks. This is a starting point for me...and maybe I should do the same about searching for the specs for that particular shock. I was doing some reading on it last night and have found much negative feedback - mostly of the shock having too much flex

You may also wanna change out the fork oil for something lighter as well.

I had an older SID. Not a bad riding fork, but yeah, they are flexy. 'Course weighing 100# less than I do, it may not be an issue with you.

M

[Mr Head]

Being light would probably be a good idea to lighten the oil up.

Oil volume and viscosity will affect the damping characteristics on a lighter guy than on heavier guys.

Get the spring and preload correct first. Then work the damping.