basically, i’ve run into small troubles with my lollipop holders. I have a Profile wheel, and basically, this is how the axle arrangement goes:
spacer, lollipop with bearing inside, thin spacer, spacer, crankarm, bolt.
imagine that^, and when I tighten the bolt, it effectively pushes everything together nice and tight. The lollipop is therefore pressed against the thin spacer and thus, movement of the bearing is very hard.
Am I doing something wrong? The design of the lollipop itself is different to those seen on Miyata frames, the bearing basically presses into one side of the lollipop, and the other side completely shields the bearing.
I would like a better description or, even better, a photo. If you tighten this assembly and it becomes difficult to rotate it may be that you are compressing the inner race and outer race of the bearing with the same spacer. On any one side of the bearing, the inner race and the outer race should never touch the same spacer (or any other surface for that matter) at the same time. Also, by thin spacer do you mean spacer with small outer diameter or spacer with small axial thickness? This is why a better description, a diagram, or a photo would be helpful.
After fiddling around with the wheel and lollipops a bit, it was made totally clear to me that the lollipops’ outer sides can not be touching any spacers at all, so it can have smooth bearing movement.
I think it’s sorted, except all I can think of that I need right now are a few more extra-thin Profile spacers.
Hmm… I never knew Lollipops could be so much hassle.
EDIT: Harper, I know it’s very vague, but it’s something that Profile hub owners would know about, because Profile cranks are supposed to be used with Profile’s own spacers. These spacers are small silver rings that come in two thicknesses: normal and thin.
I’ve figured out how to fix the problem, I think. All I need is another thin spacer to do it. Shame no shops nearby stock them.
Ok, pictures, very very bad quality. But you get the idea…
Basically, first 2 pictures show different sides of one lollypop. Then on the last picture, you can see there is a small gap between the lollipop and the crankarm, I made it like this on purpose so that nothing rubs against the lollipop.
How do people manage to use splined cranksets on lollipop frames? Anyone know how Dan Heaton or Zack Baldwin coped with their lollipops and profiles?
The crankarm on the last pic there is tightened on fully so the bolt is actually pressed against the axle end. I can’t use any spacers in between the lolly or crankarm because it will cause rub meaning the wheel won’t rotate on the bearings.
Thanks for the photos. You need a spacer with ID equal to the ID of the bearing inner race (or about 0.001"-0.005" larger) and OD equal to the OD of the bearing inner race. This way the crank bears on the spacer and the spacer bears on the inner race. The thickness of the spacer must be such that the crank bolt doesn’t bottom when tightening it. You know all this by looking at it. Can you machine the spacers? Do you know someone who can? Can you buy washers of the appropriate size to stack? The material here is relatively unimportant but I would avoid mild steel or zinc plated steel just because it rusts. Brass, aluminum, or stainless would be fine.
but, I don’t think that can work. If you look at the last 2 pictures, you see that the lollypop actually covers right over the bearing. This means that there is no bearing race exposed on the outer side sadly. So effectively, the lollypop is a metal barrier between the bearing and the spacer/crankarm.
EDIT: I think you meant the in-side of the lollypop where the bearing race is exposed. There is indeed a spacer there lodged between the hub flange and the lollypop, but on the outer-side it is completely shielded and there is no bearing race exposed so if anything touches the lollypop, then it stops rotation of the wheel, hence why I need a gap between the crankarm and the lollypop
Wow. That’s crazy. The photos were a bit fuzzy but I thought that the inner race was exposed on the outside.
I did mean the outside of the bearing, not the inside, or hub side. That really seems like a dumb way to make the lollipops for use with splined axles. For a taper it would be OK because the crank isn’t being pressed onto that surface.
I would press the bearing out if possible and bore the lollipop so that you can access the inner bearing race. But that’s just me. I’ve got access to the machine tools to do it.
The inner race has to be exposed somewhat to allow it to work at all. That is the bore of the lollipop must be bigger than the ID of the inner race. Do you know how much that is? If you can make a tube spacer that is not too thin walled it would work. If you only have something like 0.010" (0.25mm) then there’s not enough for you to work with to make a strong enough spacer.
I was actually thinking of doing something like bore-ing the lollipop. But yes, it would indeed work better by far. The thing is, is it a quick and easy job? I may just have to browse through Yellow Pages and see if any places would do it.
Harper, what kinds of places specifically, (aside from universities) would have such machinery to bore lollipop holes? If there is such a place that can offer service to the public, is it an expensive job?
Any machine shop can do it but it would cost quite a bit. Sometimes the guys that work there will do it for free if you ride for them. It depends on how nice they are and what kind of mood they’re in. Just find a machine shop close by and take the unicycle there and tell them what you want done. If you’re lucky, they’ll do it for grins.
That frame is designed (I use the term looslely) to work with a tapered axle and not on that requires the cranks to be tight to the flanges. You’ll nee to bore the lollipops out. It doesn’t need to be exact so you could use a file or a dremmel. If you are passing bristol in the near future I could pop them on the lathe or mill.
Sorry if I’m being an arse, but why not use a different frame? Or is it some special really nice custom frame you’re really attached to that happens to have lollipop bearing holders? I’ve only ever seen really cheap nasty frames (and Pashleys) with lollipops…
But otherwise I agree with Nick - if you can’t find anybody to machine them for you, just file them out - if they’re aluminium it shouldn’t take you too long to enlarge the holes enough to be able to put a spacer up against the bearing inner race. You could do it faster and more neatly with a tapered reamer like this one if you can borrow one or buy a cheap one.
I actually thought of filing a bigger hole in the lollipops. I ‘kinda’ already have a marker/guide for where to stop filing because of the marks that spacers have made on the lollypop surface. So I am assuming to keep filing until I reach maybe 0.5mm larger diameter than the marks that the spacers have made.
The lollypops are steel, so it will take a fair while with a file. I’m using a longish one with a rounded surface too.
My main problem now is actually getting the bearings out of the lollypops. People have suggested using bearing pullers, but are there any other options that can be done straight at home?
I’m now after a method to remove the bearings themselves from the lollipops. I’ve read up on Harper’s 2 methods in a related thread, but I want to save the lollipops, (I couldn’t care less about the bearings as they are so easy to obtain)
So, will some weird and wonderful tool over at Unicycle.com UK be able to carefully remove the bearings? Note: The lollipops with bearings inside, slide off the axle nice and fine, so all I’m after is a way to remove the bearings themselves from the tight clutches of a lollipop.
Evercraft bearing puller? Hammer and chisel? Anything?
Another method I thought of was the drill 3 small holes in the lollipop in the marked area made by spacer-rub. Then maybe put some metal sticks of some sort into these holes and hammer the bearing out by having those sticks smack against the inner bearing race.