Messages

331

The Bike Shop / Re: 22 inches

« on: August 07, 2013, 07:24:34 PM »

If it takes off in racing then it has a good chance. Factories understand the idea of a race and any advantage being worth pursuing. If it is a different ERTO to the Faction ones then that is a pisser, but it may well be that the Faction ones would lead to a tyre that was too big for the ******* UCI...


G.

332

The Bike Shop / Re: 22 inches

« on: July 12, 2013, 06:43:32 AM »

How much better is the 22 on the knees from hard landings?

As CMC pointed out there will be a factor related to the tyre. For a given width and pressure a smaller wheel is actually less stiff than a bigger one, so a smaller wheel would be easier on the knees. But in reality you can usually run a bigger wheel at a slightly lower pressure and get the same kind of feel and rolling resistance so that probably puts it back to the big wheel (but it will be marginal).

Another more significant factor will be spoke length. If the spokes are all the same diameter, then the longer spokes of a bigger wheel will be less stiff in proportion to the length. So a 200mm spoke will be half as stiff as a 100mm spoke (ignoring minor factors due to bends etc). But the spoke is not the whole story, the bigger rim will sit nearer to flat so this will make it seem a little less stiff too. You will also have longer fork legs, which will be less stiff than short ones.

It will be hard to quantify with all these factors and all the possible different ways you could land, but since you already tried both 20" and 24" bikes I would just say it will feel about half way between those two 


G.

333

The Bike Shop / Re: What did you do to your bike today? (v2)

« on: July 04, 2013, 04:27:47 AM »

my bell broke

ouch!


G.

334

The Lounge / Re: What have you made?

« on: July 03, 2013, 05:05:29 PM »

^^^ Looks good. Maybe just use one of your crank things for drag so it is easier to adjust.


G.

335

The Lounge / Re: What have you made?

« on: July 02, 2013, 10:14:10 AM »

Any chance of a doodle G?

I'm picturing something like a wedge of cheese shape, pivoting around the pointy bit, as it rotates round more of the curved outside contacts the string?

Not really worth a doodle. I was just thinking of a cylinder (say 15-20mm diameter) with a (maybe 6mm) hole through it. Bolt it in to one of those spare holes between two of the pulleys and let the string drag against it slightly.


G.

336

The Lounge / Re: What have you made?

« on: July 01, 2013, 05:43:53 PM »

Yeah that's probably the way of doing it, id wanted to stay away from creating friction on the line, thinking that wear might be an issue, it would be nice if the braking force was proportional to the speed too, so you get a smooth start/stop on it.

I've got a load of 608 bearings kicking around, so maybe i could do something like you suggested, but pinching the line between two bearing races, rather than static surfaces....

You aren't looking at a lot of drag, I very much doubt that you will see noticeable wear to the cord as it is moving past, you will see a small groove develop in the plastic but once the groove has worn you will have a fairly big surface and low loads with two very wear resistant materials. If the cord wears out after 1000 uses then I doubt it will be a big deal and your final item will be a lot smaller and easier to transport and adjust.

You will get a smooth start naturally anyway, and if your speed isnt too great and the line has a mellow-ish gradient and isnt too tight then it will create a dip in the line that will probably create some deceleration at the end too.


G.

337

The Bike Shop / Re: What did you do to your bike today? (v2)

« on: June 28, 2013, 05:35:20 PM »

I replaced my whole bb area:

Profile GDH cranks to socket drive Thunderbolts
Tree OG spline drive to a custom sprocket I just pulled off the mill
Bluebird to 710SL
Ezra flats plus to JCPCs

Sprocket came out nice, good work.

Not sure about that chain though.


G.

338

The Lounge / Re: What have you made?

« on: June 28, 2013, 05:30:29 PM »

^^ Maybe try bolting a simple (non rotating) bush in one of the spare holes to just rub gently against the line. Make it like an eccentric cam and you can just rotate it to vary the pressure.



G.

339

The Bike Shop / Re: Quick Questions

« on: May 06, 2013, 05:32:34 PM »

what is the best way to properly tighten caliper style brakes? (the ones that have one longer bolt that goes through the frame)
i just bought a ss/fg bike and it is giving me hell to get the calipers centered so one pad doesn't always rub, and i cannot for the life of me get the pads straight and tight with the braking surface of the rim.

It depends on the brake. In the "bad old days" some calipers had a habit of creeping round when you tightened them and it was nearly impossible to keep them straight. Weinman brakes used to need a special little socket ended wrench thing (which I still have) to hold the bolt while you tightened the back. Some modern ones have a hex key socket ont he front to hold them still and some need a thing like a cone wrench to hold the spring holder... post a picture of the brake if you still cant get it..


G.

340

The Bike Shop / Re: What did you do to your bike today? (v2)

« on: April 06, 2013, 04:43:02 PM »

You expect kids to take of the wheel, tire and then also patch the tube?!

You don't need to take the wheel off to patch... so it can sometimes be less hassle than changing the tube...


G.

341

The Bike Shop / Re: Quick Questions

« on: April 06, 2013, 04:39:17 PM »

To clarify: the front is going well and hopefully will be out relatively soon.

The rear is taking a little longer and probably wont be out until the late summer at the earliest.


G.

342

The Bike Shop / Re: Quick Questions

« on: April 05, 2013, 06:40:50 PM »

Anyone know a release date for the new G-Sport Simian hub??

No.


G.

343

The Bike Shop / Re: What did you do to your bike today? (v2)

« on: March 26, 2013, 08:55:10 AM »

You are still removing material which is not a good idea. Would have been much better to simply use "the penny trick" to get it on.


G.

344

The Bike Shop / Re: What did you do to your bike today? (v2)

« on: March 25, 2013, 10:09:39 AM »

I hesitate to ask this but... what were you filing?


G.

what would one file to make a round rod (steer tube) fit into a round hole (stem?)

You need a picture?

I had thought that maybe you were filing the slot wider like TCBMX described OR doing something like this, but I was kind of hoping that you weren't doing what you did...

PLEASE dont run the stem like this, just warranty it.

If a stem has pinched then it has yielded. This goes for ANY pinch-bolt stem (or crank or brake lever or whatever), and ideally (in terms of safety) it should be replaced. In the case of Odyssey/Sunday stems we will happily warranty them (assuming that there aren't obvious signs of over-tightening abuse. Though to be honest if it has yielded like this then it has almost certainly been over-tightened, but we are pretty generous with the warranty).

Filing/sanding out the bore like this is a really bad idea. When the stem pinched the stem yielded and the hole effectively became larger (albeit with the slot closed up), by making it a bigger bore you are making things much much worse, it will now need to pinch closed even more to fit the steerer and the bolts on the back will be even more misaligned and likely to break and the stem will clamp less well and be more likely to slip.

I hope this makes sense and is helpful.


G.

345

The Bike Shop / Re: What did you do to your bike today? (v2)

« on: March 24, 2013, 04:54:15 PM »

took a file to my freeze stem.

I love when what should be a simple ten minute part swap turns into a cuss fest. Stem pinched and I hate doing the nickle/washer trick. file, file,file, file, cuss cuss, file.

fits well now!

I hesitate to ask this but... what were you filing?


G.