Alt Bike Culture - damn it....

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View Full Version : damn it....


kemmer
01-27-07, 01:11 AM
... my tall bike is broken and I don't have a welder to fix it. I guess I'll be freak-bike-less for a couple of months till I can afford/borrow a welder.


wethepeople
01-27-07, 02:47 AM
Duct tape. Come on, it's not like they're safe anyways.

What broke on it?

wethepeople
01-27-07, 03:01 AM
Also, does your tallbike ever skip when you pedal hard?

I had a bad skip the other day that bent my chainring to hell and back, I had to take it off the bike and hammer it straight, couldnt even bend it when it was on the bike. I also had a skip my first day riding it, throwing me over the bars into a snow drift.


Brian
01-27-07, 11:58 AM
Muffler shop.

kemmer
01-27-07, 03:22 PM
The bottom frame is jacked. One of the seat stays is bent really bad. I straightened it, but they were super crappy and wimpy to begin with and the thing just looks like death on wheels now. I don't trust it at all now. I'm planning on fabricating a long rear triangle, but it's gonna have to wait till I can get access to a welder.

kemmer
01-27-07, 03:59 PM
Also, does your tallbike ever skip when you pedal hard?

I had a bad skip the other day that bent my chainring to hell and back, I had to take it off the bike and hammer it straight, couldnt even bend it when it was on the bike. I also had a skip my first day riding it, throwing me over the bars into a snow drift.


What do you mean, like the chain skipped?

wethepeople
01-27-07, 04:10 PM
ya, chain skip/jump/whatever.

Mine does it when I stand and pedal sometimes.

ianjk
01-29-07, 12:21 PM
Chainskip on a tallbike can be a big problem, especially when climbing.

It is worth it to put a new chain on it if you are currently using an old crusty one, I run a 3 speed hub and have to use a 3rd cog (bottom frame bottom bracket) in the drive system to allow for adjustment of the chain tension due to horizontal dropouts being almost perpendicular to the top bottom bracket. I only have a couple of teeth on the rear cog in contact with the chain, which can lead to skipping under load with a crusty chain.

Also, on my old tallbike (decommissioned, awaiting rebirth as a chopper/sled/trailer or something), I had a lot of flex between the frames (connected at steerer with peice of galvanized conduit (bad idea)), which would cause the chain to skip when cranking out of the saddle. I could actually throw the chain off when I cranked really hard (usually on a hill, resulting in emergency dismount and embarassement).

Pay close attention to the weld at the bb and how you connected the headtubes. I ended up connecting the headtubes on my new steed with an old top-tube and then made an extended steerer on the fork that runs all the way through to the stem/headset. It is much stronger and feels 10x better on the road. I also did about 4 welds around the bb, alternating direction (horizontal -> vertical -> horizontal -> vertical) so there is a nice buildup of material. (I am a noob to welding, built about 6 freakbikes now and learning something new everytime I play around, not sure if this is the best thing to do, but it worked for me).

kemmer
01-29-07, 12:45 PM
If the frames flex too much under load, the chainline can actully change and will cause you to drop your chain. Your bike looks pretty solid and your chain is slipping, not dropping, so I would check to make sure your chain isn't too stretched and that your cog/chainring aren't worn. Are you using a ramped cog from a cassette or a single speed cog? SS cogs work better, but you can probably get away with a ramped cog if it isn't badly worn.

wethepeople
01-29-07, 03:35 PM
I'm using a single cog from a cassette in the rear, it only has one ramp on it but the teeth are straight. In the front I'm just using a third ring. I dont know how bad the chain is stretched, it looked brand new and I have perfect tension on it all, I found a magic gear thats 46-18. A little high but I can deal untill I get my new wheel.

kemmer
01-29-07, 03:41 PM
Check your chain, I'm guessing thats your problem. Or wait for your new wheel and see if that solves it. It the chain tension is right and the cog is in decent shape, I'm guessing that sucker is pretty stretched.