Bicycle Mechanics - 36 cross 1. Anything I need to know?

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FastJake
10-17-11, 10:06 AM
I've acquired an old Dura Ace front hub and a Mavic GP4 tubular rim. I've built about a dozen wheels; they've either been radial, x3, or x4. I'd like to try 36x1 on this wheel, as 36 spokes is certainly overkill for me on a front wheel (I'm 130lbs.)

Anything I need to know before I order the spokes? Any other advice? This will also be the first time I've glued a tubular tire, so any advice on that is appreciated!


Ex Pres
10-17-11, 10:27 AM
If you've built X3 and X4, X1 is really no different, except you count less holes to begin lacing if you want to line up the hub label with the valve hole.

Quick version of gluing up tubulars.
1. Stretch the new tire on a rim for at least several days. Install and pump it up to full pressure. I like several weeks myself. You can even use a clincher rim in a pinch. Deflate, remove, proceed to next step
2. Apply a thin but complete side-to-side layer of glue to the rim, and the same to the basetape of the tire. Depending on the rim width you probably can leave a small (like 2-3mm) uncoated strip on each side of the basetape. Allow to dry about an hour or more.
3. Apply a thin coat to the rim only. As soon as you are done applying, immediately mount the tire valve first. Pull the rest of the tire up around and over the rim. Depending on the tire, you may need to stand on the rim (pointed upwards) and pull the tire up (no shoes and socks makes this easier for me anyway.)
4. Adjust the tire by looking at the exposed basetape all around the rim. You may need to pull back and forth in some areas.
5. Inflate to about 20-30 pounds. Hold the wheel up and spin it looking for tire trueness. You can also do this mounted in the bike or in a truing stand. Readjust the tire as neccessary.
6. Inflate to full pressure. Allow to dry overnight.
7. After all is complete you really should look to make sure there are no gluing voids. You can do this by deflating and pushing the tire up with your thumbs as you make your way around the rim. Don't push so hard that you are "ungluing" the tire, but do apply some pressure. If it comes away too easily, that's a void. Peel it up and reapply the glue locally, unless it's a really big void.
8. Ride

You can apply the glue with flux or other brushes. I personally find I make the least amount of mess by sticking my index finger down into the end of a baggie and using that to spread the glue.

FastJake
10-17-11, 03:44 PM
Thank you! I'll order the spokes tonight.

Thanks for the tips on the tubular tires too. I've watched some videos on how to do it, but the more info I have the better I feel.


cycle_maven
10-17-11, 04:37 PM
Make sure your front hub can be laced 1X! 1X is nearly radial as far as the stress on the hub flange goes. The hub should be rated for radial builds and it should never have been built up before; otherwise the spokes from the previous build will have raised up some material from the flange and weakened it to pulling from any other direction. Otherwise, I'd just go with 3X.

fietsbob
10-17-11, 05:38 PM
I've acquired an old Dura Ace front hub

it is commonly considered best to re use a hub
and not make a different set of metal distortions in the flange

if 3x re lace it again, .. you can use a light DB spoke
since it will have so many of them, and it's a front.

Soil_Sampler
10-17-11, 05:44 PM
Anything I need to know before I order the spokes?
Any other advice?

Don't.

If you want to build a wheel that you haven't, go 2X.

But, I would build it like fietsbob suggested.

dddd
10-17-11, 06:25 PM
I've seen more than one low-cross wheel pull it's hub flanges to pieces while sitting in storage.
Aluminum doesn't like to be tensioned for long periods, as it yields and disociates over time.
Those Ksyrium alloy spokes are a very special alloy.
Never re-lace a hub to a different pattern, for same considerations.

mrrabbit
10-17-11, 07:11 PM
http://www.mrrabbit.net/wheelsbyflemingapplications.php

Grab the spreadsheet...see the t-chart tab.

=8-)

BikeWise1
10-17-11, 08:42 PM
1x in this application is beyond useless.