Spacer Machining

[Kurlon]

Anyone up for cutting a couple wheel spacers for me?

Two spacers, stepped, only difference between the two is the length of the larger OD portion:

Spacer ID: 0.667in
Spacer small OD: 0.867in
Spacer large OD: 1.085in

Spacer A:
Small OD length: 1.000in
Large OD length: 0.461in

Spacer B:
Small OD length: 1.000in
Large OD length: 0.786in

I'm looking for hand press fit into 20mm ID bearings, making them captive, there will be a 17mm OD axle going through them, all measurements were by hand, if you've got experience making spacers and want to suggest better targets I'm happy to learn. The length of the small OD section isn't critical, it goes into a 12mm wide bearing, I figure another 12mm minimum past that to catch the wheel's inner spacer is good?

[MarkMarine]

I have some 6061-T6 billet, I can do these for you but the lathe is kinda old so the tolerances aren't going to be more accurate that .005
Without seeing/measuring the hard parts, I don't want to give input on the design/tolerance part. I'll put them into CAD real quick just so you can approve the dimensions, then cut them for you.
How about $40 for these?

[Kurlon]

Heh, no hard parts exist yet, this is all based on scary math and the OEM spacers and rotor mounting faces, accounting for the old rotors being dished 9.5mm...

I can pull the axle and bring the target wheel to the track this weekend if you want to check measurements yourself first though?

[MarkMarine]

Heh, no hard parts exist yet, this is all based on scary math and the OEM spacers and rotor mounting faces, accounting for the old rotors being dished 9.5mm...

I can pull the axle and bring the target wheel to the track this weekend if you want to check measurements yourself first though?

Sure, bring the parts to the track, better still let me take them home. I can do the design side and bring the master machinist downstairs in the prototype lab the parts (and bribe him with a 30 pack), and I'll be damn sure you get spacers that fit.

[Kurlon]

Axle has to come home with me, need it to keep the current front wheel on the bike.

Lemmie stew on this tonight.

[jasnmar]

See if there's someone local who can print in plastic for measurement sake. If plastic works you now have a prototype to build the real thing by (tolerances will come into play, but it's better than guessing).

[MarkMarine]

If you take the measurements with accurate tools, I'll make them right. Just, with fits you want to be pretty accurate so they press in and hold right, or always clear without slop (since it's locating your wheel, and it's a race bike.) So the factory bearings won't be an issue, but take a couple measurements of the axle in different spots just to be sure. It's better to use an inside micrometer, calipers will lean one way or the other (be diagonal? I dunno how to describe this) and not always be right on, unless you're sure you got that right.

[wheelieman14]

Mark, you can use either a 1st Gen SV650 Front or Rear Axle to check fit for spacers, since I believe they are both 17mm O.D.

[MarkMarine]

This is for an SV? I figured it was for his crazy frankenbike

[wheelieman14]

Model of bike doesn't really matter, since a 17mm axle is a 17mm axle, as far a motorcycle manufacturers go... Just suggesting that you use one of your axles to check fit, since you should already have that size sitting on your race bike.

[MarkMarine]

while 17mm = 17mm, all manufacturer's products are not created equally. I don't mind machining something off the dims that are up there (except a "hand press fit" doesn't exist) but I just don't want to do all the work for this and find out they don't fit. Just trying to dot my i's so I don't have to iterate this a bunch of times.

[wheelieman14]

I understand your point about precise measurements, but since motorcycle wheel axles are generally built to specifications of standard bearing sizes (6204, 6305, etc.) it seemed like an easy way to double-check the fit without taking Josh's axle from him. FWIW, his provided Spacer ID: 0.667in x 25.4mm calculates out to 16.9418 mm. Hopefully there is enough clearance from a standard 17mm axle diameter to still fit properly. There is "snug" and also a pressed on fit, which might be okay for spacers, but not for axles.

[Kurlon]

I'm going to hold off until AFTER this weekend so I can A) get my micrometer's cleaned and calibrated and B) get a second opinion on my measurements. Once I've got that on lock down, then I'll hit ya up.

[Expat]

The spacer wants to be clear on the axle as it is only a "spacer". It needs to slide inside the seal on the wheel so again, plenty of tolerance there.
+/- 0.005" on the O/D's and lengths should be fine, the critical one is to make sure it is a clearance fit on the axel so I would bore to 0.005" larger than the axle should be good.

[Kurlon]

Bringing this back to the top. I had a test set cranked out locally... got my left to right / length dimensions spot on (after a lil re-doing my math...). O/D and I/D however were not what I was looking for. 'Hand fit' was '24oz Ballpeen shitshow' fit into the bearings, and axle into the spacers. D-oh! I still can't relenquish my axle as it's the only one I've got (will be trying to remedy that as I like spares) but I can at least provide the wheel now. Still game for tuning this setup Mark? I dunno if you want to just cut on the spacers I've got or cut fresh ones but I'm game either way. The proof of concept showed it's viable though so now I need to finish it.

[CBR929RE]

sounds like you aren't designing them right. are you making a lip on the inside that fits behind the seals?
the captive spacers I have are from Ten Kate Racing as they were the only ones at the time that made them for a cbr600. I like the beveled outer edge much better than flat edges.
here's pics of mine (I only have rears) and ones that FastFrank Racing makes, both have the inner lip to be held by the seal.

[Rada]

sounds like you aren't designing them right. are you making a lip on the inside that fits behind the seals?
the captive spacers I have are from Ten Kate Racing as they were the only ones at the time that made them for a cbr600. I like the beveled outer edge much better than flat edges.
here's pics of mine (I only have rears) and ones that FastFrank Racing makes, both have the inner lip to be held by the seal.

Something new..
http://www.drivenracing.com/content....vewheelspacers

I bought a couple sets for the Gizzer.. Very nice

[Kurlon]

I don't run seals, so I don't set the spacer up to catch them. (That also seems like a good way to tear a dust seal by accident.) I'm going from a wheel setup for a 22mm axle to a 17mm axle, so instead the spacer has an inner portion that goes inside the 22mm bearing and supports the spacer between the bearings like the axle would. (My OEM wheels are actually setup this way also out of the crate.) The problem I had is I don't have the proper tool for measuring OD / ID, so the numbers I got with my caliper plus what I was told should be proper clearance turned out to be off. I was able to polish the ID of one to get it close to a slip fit on the axle so I'm not THAT far off...

[CBR929RE]

gotcha

[Rada]

I can hook you up Kurlon...

[Kurlon]

Horrible diagram to be posted today.

[Kurlon]

Behold my amazing cad/cam skills. Spacer #1 and Spacer #3 are the viable units, #2 was a gaff in my spreadsheet. Dimensions C and D are where I'm off.

[Tunertype]

Behold my amazing cad/cam skills. Spacer #1 and Spacer #3 are the viable units, #2 was a gaff in my spreadsheet. Dimensions C and D are where I'm off.

Nice! What program did you use? FeltTip or BallPoint? You could get a cheap 1" micrometer and bore gauge to get you closer.

The tolerances you need to be a snug fit are going to be less than 0.001". More than a couple thou in one direction or the other and it'll either be sloppy or be impossible to jam in. If your just going for 17mm(0.66929") and 22mm(0.866142"). Then I'd dimension them at C = 0.8666 +/-0.0005 and D=0.6698 +/-0.0005. If the dimensions you got were the ones in the drawing and you were trying to fit it into 22mm and 17mm holes and shafts then you had more of a press fit. If you don't define a tolerance lots of machine shops will take between 0.002 and 0.005 tolerance on 3 decimal places. A lot will also ask if it's doesn't include tolerances.

Edit: http://www.engineersedge.com/class_iv.htm snug fit listing. As much as .0002 interference and .0018 clearance for snug fit.

[number9]

Anyone here that can help me machine up a very simple spacer? Basically a hollow tube, no threading needed. Can be aluminum or mild steel, maybe 2" long. Will pay cash, beer etc.

MarkMarine moved back out to CA

[Larry]

What do you need and how fast? I have finally started moving equipment to my home shop and have my CNC mill up and running. Just waiting for a variable frequency drive for the lathe and I'll be ready to rock. If its really simple I can knock it out at work during lunch.