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Discussion Starter #1
this afternoon i laced a set of wheels for my cb 350, stock hubs and new steel rims and spokes, can you guys give me some idea as to run out limits, i started truing the front and the side to side is about .010 tir, seemes prety good but what would you think side to side and vertical numbers should be? thanks
 

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done tons of wheels...both bicycles and motorcycles. a tenth of an inch is barely ok. slow street bikes are more forgiving than (low profile tired) faster racers. if you can get it better without rolling the nipples over, keep getting it better.
-parks
btw, road racing bicycles are the most finickey as the tires are very close to the rim and the brakes rub the rims. any outage is felt right away.
 

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Discussion Starter #3
hey parks i'm at 100th of an inch .010 so is that good enought for a formula cb bike
 

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I would think .010 will be fine for average street riding. If it will be in the track then you might want to get a bit better if possible. At high speeds and high speed turns you might feel some vibrations. Where did you get your rim from?

Rochester, NY
74 CB450
73 Triumph Bonnie 750
80 KZ1000 drag/street
 

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Discussion Starter #5
the front is a union cycle and its a bit out of round [.075] and side to side its [.010] i just started truing so ill have to see how good i can get it. the rear is a DID and looks better quality, but i have not put it in the truing stand yet. im hoping to get some target numbers so i'll know when its in spec,
 

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.010" side to side is fine and dandy...even .015" ( the tires will be no where that close anyway).

Up and down....you gotta get it about the same....tough read sometimes because of the weld seam....you gotta just ignore that bump as long as it's not stupid out of whack. I'd shoot for about the same up and down .010-.015"....not including the weld seam bump.

Some of the Chinese alloy rims are almost impossible to get better than about .030". But DID, Akront, Excel etc... usually no problem.

You'll always find some rims, even good ones, with anomolies...shoot for kind of an average run-out rather than short bumps and dips. When you get it close you'll be able to spot a single loose spoke on the indicator.
JohnnyB
 

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Discussion Starter #7
thanks john, i think i'l try the DID rim then go back to the cheaper front rim,and see how good i can get it, i was worried about the lacing bit, turns out it was not that hard after all,now if i get them round i'll be feeling pretty good
 

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You'll do fine. Once you get a system down to pull it this way or that you'll do fine. Remember...two ways to move the rim in a direction...tighten the side you want it to move to....or loosen the side you want it to move away from.

For up and down run-out. Pick the "low" side and loosen a bunch of spokes on that portion of the rim about half a turn....measure again....if it needs more....then tighten the spokes on the "high" side half a turn....check again. You have to keep in mind for the rim to move well in any direction...it's not just tightening in one directions...it's loosening the opposing spokes so things have the slack to move a bit.

When you get it where you want it, you go around the rim snugging up any loose spokes (not enough to change the shape). Then go around and start tightening every spoke about a quarter turn until they all get close to as tight as you want them...checking now and then for run out and adjust as you go.
Usually when they are all about 80% as tight as you want them you'll be able to go ahead and tighten them all up without pulling the rim out much at all.
Hopefully BFD will chime in here...he builds bicycle wheels for a living.
JohnnyB
 

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3 different people tried the rear on my racebike, and no one could get it better than 015. we spent hours on that thing. i think the book says something nuts like .025. which if you spin it at that it looks rediculous. i do it about the same way as john. ive seen guys almost eyeball them in to spec. guess if you do it a million times, its easy.

i was told by someone who went to buchanons that they have a jig. they loose lace the wheel, then it goes into a jog that holds the rims and hub perfect. then its automatically comes in and tightens it down. when they pull it free, its perfect. everything torqued, done. i dont know if its true. but it seems like the volume would require something like that.



jc

i dont know shit
 

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Discussion Starter #10
i did the rear this afternoon, and it was much better right away, even before i started it was better than the front, i still have to go back and toqure it down but right now its like .005 out of round and side to side about .008, not counting the seam, i'll have to go back and re work the front one, now that have a little experince.
had to order a proper spoke wrench, i think i have almost every tool known to man but no spoke wrench, i used two dial indicators on the rear so i could watch the wobble as i did the rounding and vice a versa,feels good to have some success,
 

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Joe
virtually all low-mid end bicycle wheels are completely machine built and some high end are machine built but finished by hand. Luckily a machine can't replace me yet..... It doesn't surprise me that Buchannons uses a machine to build with, their labor rates are too cheap for a bunch of human hands.
With regard to your rear wheel sometimes I'll replace the spoke at the problem area or swap 2 spokes in different areas to see if it's a rim error or a spoke/rim interface problem.
Midge
Those tolerances are probably as good as you'll get. You probably found with your do-over that it was started a little off, and it's really hard to get back without starting over. I make sure I start all nipples the same amount of turns and turn the wrench the same amount on every spoke as I go, only accomodating dents or wobbles.
After you finish this set you'll probably go look at all the other bikes in the garage:)
 
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