Laced up a spoke 21" last night!

[Briggs&Stratton]

I laced up this 21" wheel last night for my xs11. Its an early 80s Yamaha xs650 heritage special 64 spoke hub with a custom spoke kit and rim hoop from mikesXS. It has a bolt pattern on both sides that'll allow me to keep my stock dual disc brakes.

I've never laced a wheel before but was able to with the sporadic tips I gained on the internet. Conflicting info led me to lace it incorrectly twice, but I finally got it handled. Obviously, it has to be put together in a very specific way and has 4 different types of spokes.

Still have to true it up, so if anyone has any spoke wheel truing tips, I'd appreciate it!







Clean, new parts, so I got to assemble it in my living room haha. Next to natemoens favorite shotgun!

[crazy steve]

Be very careful once you have that installed and are riding.... The 21" tire has about 1/2 the contact patch of a 19" and will wash out much easier. I know more than a few guys who pulled the 21" front wheel off their Harleys after going down because of these. And I wouldn't normally recommend this, but removing one front disc is a good idea also. Not enough tire for two....

[jetmechmarty]

And I wouldn't normally recommend this, but removing one front disc is a good idea also. Not enough tire for two....

I don't believe Harley-Davidson builds any bikes with two brakes on a 21" wheel. I believe 21" wheel bikes have the front brake dumbed down.

Nice job on the lace-up!

[Bikes]

Looks good, cant wait to see it on the bike......
Never laced a wheel before....always seemed a little "Greek" to me.....

[crazy steve]

I don't believe Harley-Davidson builds any bikes with two brakes on a 21" wheel.

They don't. Nobody else does either. When the chopper guys first started running these, they didn't run any front brake, which arguably may be just as safe.

I've personally seen a guy go down from hitting one piece of gravel on a paved corner while doing the posted speed limit when the tire 'skipped' and did not regain traction, and know of other similar cases. If you're building a slow-speed bar-hopper the 21" is fine, but cornering/braking capabilities are badly reduced. All those speed warning signs at corners now mean something...

[natemoen]

Next to natemoens favorite shotgun!

You and your fancy chrome zombie shotgun....

[DiverRay]

True up the rim? EASY, sort of. Put the axle in the rim, and mount in your vise(NOT that one!). Use a soft pencil, or sharpie, and spin the wheel as you SLOWLY move the pencil in close to the outside of the rim. Watch for up and down, or side to side movement as the wheel turns.
Let the pencil just touch the rim as it hits the high point from one side. Then do the same from the other side. You then tighten up the spoke 1/8 turn at a time on the opposite side of the rim from the pencil mark, erase, and go again. Don't forget to watch the "round" part of the rim, putting the pencil so just the top edge hit the lead to mark it.
Go slow, expect about 2 to 3 hours on the first try, and have fun. I used to do rims for a Yamaha shop back in the dark ages, before I got an edumication...

[Prisoner6]

Be very careful once you have that installed and are riding.... The 21" tire has about 1/2 the contact patch of a 19" and will wash out much easier.

+1 ...

A few years ago, a riding buddy let me try out his H-D with a 21-incher mounted ... I had a couple of really scary moments turning corners!

No, thank you ...

[donebysunday]

So it's the thinner tire causing the traction problems ?
I've never put a 16 on the front, the ones I've seen I like that look too.
My Radian had 110-90-16 front and 130-90-16 rear and handled well.
Could a wider rim be used for a fatter tire, or are 21" tires all skinny ?
I would think you would need more brake with the greater leverage of a taller tire ?
I've never been there and don't plan to.

+1 ...

A few years ago, a riding buddy let me try out his H-D with a 21-incher mounted ... I had a couple of really scary moments turning corners!

No, thank you ...

[jetmechmarty]

UD,
There are 21" dirt tires that put down the rubber, but in this case, it's a styling exercise. The 21" wheels put less rubber on the road, so less braking is available where the rubber meets the road.

I have a friend who modified his HD to 21" wheel. It also has forward controls as most of them do. A couple years ago, he was following too close behind an old pickup truck. It had no tail/brake lights. It stopped and he ended up making a panic stop. The set-up being what it is, the rear wheel locked up immediately. Your brain tells your feet to move under you when falling is imminent. Yep. His foot lifted off the brake and high-sided him. He recovered, but he broke two vertebrae, his scapula in three places, several ribs, and a bruised lung. When I saw him in the hospital, his head was swelled up like a melon from air that leaked out his lung. The long sleeve tee shirt he was wearing did little to protect him from road rash. The up side is that he was wearing a DOT approved half helmet. It absorbed the shock when his head struck the ground and he sustained no head injury. I don't know if the helmet saved him or not, but it definitely hit the pavement.

If you're riding a bike that puts form over function, please do so within its limitations. Be aware of those limitations!

That being said, I look forward to seeing how this custom turns out. I expect it's going to be pretty!

[Arthur_of_Hex]

When I'm handed a wheel to relace after powder coating I turn to my rim teachers of past. I use a static balancer to allow precise spinning of the wheel as well as razor sharp accuracy with a harbor freight dial indicator. Step one, true the radial runout, ie, the roundness of the wheel in reference to the hub. Inwas taught to divide the "groups" of spokes equally and start with groups. Example. Wheel has 10 groups of 4 spokes. I mark every other group of 4 with masking tape on the rim then number the tape 1-5. So I have 5 groups of 4 to start truing. Essentially a 5 spoke wheel, ( using a group of 4 as one "spoke") I found this makes truing very handy since you are lightly tweaking 5 groups of 4 first and not messing with all 40.

Once radial runout is close, switch to side runout. Remember, don't move the rim from one side to the other, move both sides in. Meaning, if your dial indicator says it's wavy to the left in one spot. Lightly tighten that spot right, while lightly tightening the rest ever so slightly left. Both to center.

Once radial and side are within .020 or less, I like .010 or less, and when you spin the rim it looks smooth when you look across the outer edge...bring the remaining spokes snug with your fingers.

Mark a starting spoke, turn it 1/4 turn tight, move ahead 3 spokes, repeat 1/4 turn tightening, continue this around the wheel. Do that for an hour or so until they are all equally tight. Torque wrench to the old spin the wheel, allow the spoke wrench to lightly tap them and make sure the tone sounds the same, the loose ones show up really quick.

[Briggs&Stratton]

Diver and Arthur, thanks for the tips! Very detailed, I appreciate it!

[fredintoon]

.... The 21" tire has about 1/2 the contact patch of a 19" - - -

Hi Steve, you got me puzzled on that one.
A 21" tire has a longer radius than a 19" tire and thus should theoretically put slightly more rubber on the road so long as they are both the same width.
I'd go with a 3"-21 tire has a smaller footprint than a 3.5"-19 tire
although I'd say 3/4 the contact patch would be closer.
FWIW, my 1937 KSS Velocette (SS was for Super Sport) ran a 3"-21 front while it's KTS (TS was for Touring Sport) brother ran a 3.25"-19.
And even the mighty Vincent ran a 3"-20 up front.
But those bikes were designed to run on those size wheels, the Velo front brake was pathetic and even the Vincent's dual front stoppers weren't up to much by modern standards.

[Briggs&Stratton]

Laced, trued, tightened, and tire mounted. Here's some pics. Maybe this will give a good visual of the footprint differences between a 100/90-19 and a 90/90-21 of the same brand and tread pattern.

[natemoen]

Does look a bit narrower, but then you also used a narrower tire!