tiger1964 

A next step in my quest (I had another topic on freewheel cog count a few days back) to go from 2x5 to 1x7 on a Campagnolo equipped bike, I need to change the axle spacing. Looking online, it sounds like to go 7-speed I need 130mm OLD (True?). With each dropout about 7.4mm thick, I cannot go over 144mm total axle length, but don't want it too short either. I see there are 140mm axles in existence -- do all Campagnolo rear QR axles interchange (Record hubs BTW)? If not is there a part # or markings to look for when selecting an axle? Are there non-Campy () axles that fit?

I read one mention on-line that 140mm axles can bend. Hmm, I wonder if there are precautions I should take. Gee whiz, it's only a few more mm.

mpetry912 

you're going to spread the frame, right ? since you are using a campagnolo hub you can go to whatever Over Lock Nut (OLD) dimension you want that will be sufficient to give clearance for the chain when shifting onto the smallest FW cog, build a spacer configuration to achieve that OLD, and add 10mm to the OLD for the overall axle length.

So at 130 mm OLD, you'll want a 140mm axle. The Wheels Manufacturing chrome moly axles are very strong and work great. you might not need the full 130mm, 126mm may be sufficient. and you will want to re-dish the wheel.

/markp

bulgie 

7-speed originally was used on 126 mm wheels, but only if the inner portions of the seatstay and chainstay were trimmed or flattened. Better quality frames (especially Italian, American and Japanese) tended to have the needed clearance, but some stubborn English and French builders continued to use domed-end stays that were not trimmed/flattened for chain clearance. On those, you might need as much as 3 mm more stickout on the right.

More axle stick-out means more wheel dish and more leverage for bending the axle. So me, I'll always grind the offending metal off the seatstay, even though it ruins the paint locally, because I won't accept a frame that's made wrong. And it's definitely wrong to have the stay prevent the chain from shifting, with a properly spaced hub.

Anyway, historically, 7-speed wheels were sometimes spaced 128, but that was never a standard, more of a kluge.

130 first came along for MTBs, was never a standard on the road until 8-speed.

BTW you need almost no axle sticking out past the locknut. A millimeter will suffice. It's only there to locate the wheel until the QR is closed, after which it's no longer weight-bearing. All the stress is taken by friction between the dropout and the hub locknut and QR.

So, respacing from say 121 to 126 mm can almost always be done without swapping the axle for a longer one. Unless the axle was abnormally short to start with. My advice, try it with the existing axle before you buy a new one. Done it many times myself, and it's Sheldon Brown approved!

Yes, 7-speed freewheels varied in width depending on brand/model, and some may need a bit more freewheel space on the hub to keep the chain from hitting on the seatstay. Some trial and error may e needed, but I'd rather shop for one of the narrower 7-sp FWs than accept a sub-optimal hub spacing.

Mark B

SurferRosa

Depends on the 7-speed and the hub!

I've been using the all-chrome looking Sunrace 7-speed freewheels. The last couple hubs I've worked with have both been a little under 126 (like 125.5) and had ample clearance for the chain in the stays on that freewheel. I remember a couple I built up previous to that being closer to 127.

Note to self: when sawing an axle, measure twice and add back 1-2mm.

tiger1964 

Quote:

Originally Posted by mpetry912

you're going to spread the frame, right ? since you are using a campagnolo hub you can go to whatever Over Lock Nut (OLD) dimension you want that will be sufficient to give clearance for the chain when shifting onto the smallest FW cog, build a spacer configuration to achieve that OLD, and add 10mm to the OLD for the overall axle length.

Yes, this will be my second “cold setting” bike. It sounds like I should get the freewheel and see what I need to clear FIRST, then decide if I need and axle, and which one.

Thanks for the comment on Wheels Manufacturing, plenty of axles and the price is not too bad. So, for a Campy Record, I want 10mm x 26tpi, right? WAIT A MINUTE, I forgot, this first bike has those Avocet sealed bearing hubs, and I’d like to continue using them - so same question… What diameter and thread? I guess I can simply put a digital micrometer on the axle, is it that simple? And I can try threading a Campy locknut onto the Avocet hub. The next bike does have Campagnolo hubs.

OK, I looked at the Masi and, to my eye, the inside of the dropouts are finished off nice and flat, it sounds like a good sign. If I have to grind a bit, OK as, longer term, I suspect I’ll have the frame refinished.

That scares me, but I am listening. 1mm?

…and…
Well, I went to the expert here on freewheels, and I am being steered towards a Sach Aris.

esasjl

I'm using 7-speed SunTour Ultra (Winner Pro) with 126 mm OLD (1990 Gitane). The rim has 3 mm offset to improve dish and the stays are flush with the drop-outs reducing DS overhang. I used a longer axle on an originally 120-mm OLD Zeus Gigante hub and added an outrigger bearing given the effort involved and scarcity of parts. Mines a 3x7 and I'm very happy with it.

dddd

I've built many rear hubs/axles/wheels for a variety of spacings to accomodate different frame widths and different freewheels.

A 7s freewheel protrudes further out past the drive side flange than a 6s freewheel, and even protrudes outward slightly more than a 7s cassette.
Yet I've built strong wheels for use with 7s freewheels to as narrow as 123mm at the locknuts.

I recently added a mere 2mm spacer to the driveside end of the axle in order to fit a standard-spaced 13-26t, 6s Uniglide freewheel onto My SR Maxima's original 120mm-spaced Superbe Pro rear hub, and it's now working great as compared to the smaller Ultra-6 freewheel that the bike came with.

One secret is to measure carefully what the driveside axle spacer extension gives out to the face of the locknut relative to the outer face of the smallest cog.
I've used as little as 3mm there and which gave adequate chain-running clearance using 7s chain. Using the absolute minimum of clearance to the dropout makes for a stronger axle and a stronger wheel within the available frame spacing.
Good spoke tensioning and use of a strong rim like an MA2 can make for a surprisingly strong wheel!

As far as the seatstay end possibly protruding to the point of contacting the moving chain during a shift from the smallest cog, most don't need any work, and those that might need Dremel-clearancing with a 14t cog might not need any with a smaller top cog.
I just look for any gouges from the chain and grind away a bit of the offending protrusion.
Where you might as likely encounter clearance problems is with any claw-mount bolt/nut hardware, or with one of the screwed-on, two-part axle stops, or with any rack or fender bolts/nuts that may protrude inward.

I built this wheel to 124mm using a 7s freewheel, it's pretty much bomb-proof and the hub's axle extension is actually shorter than what some 6s OEM hubs came with.
It slipped into the dropouts of an old Peugeot set at perhaps 121mm with little fuss.

bulgie 

Pretty sure Avocet sealed hubs have non-standard axles with unthreaded lands where the bearings press on. It's a good design, no thread right under the bearing makes them less likely to break, but they're not interchangeable with anyone else's.

Back around 1980, I tried to use one with a Campy M10 axle, but there was too much slop between the inner race and the axle, and you can't adjust it out.

bulgie 

OK, 1 mm is a bit of an exageration. It could theoretically work but it's complicated. Most axle ends have around 1 mm of chamfer, so if you literally had 1 mm of axle stickout, it wouldn't even touch the frame at the full 10 mm diameter. But if you cut it very square with no chamfer then yeah, 1 mm could work. But you pretty much never need to try that when going from 5-sp to 7-sp, there's enough axle there.

I mentioned "Sheldon Brown approved", but here's the actual quote: "As long as you have 2 or 3 mm sticking out on each side, that's plenty." (It's here, halfway down the page)
St. Sheldon did not sign off on one mm! I'm pretty sure he did experiment with a wheel with zero stickout, where the only thing locating the wheel in the dropout is the 5 mm QR skewer, and he pronounced it strong enough. But a PITA to center the wheel in the frame. Maybe useful for someone with vertical dropouts who wants to run fixed or SS. Sorry I don't remember where he wrote about that, maybe on a forum, mailing list or rec.bicycles newsgroup.

SurferRosa

Pics? Heelllloooo!

tiger1964 

Quote:

Originally Posted by dddd

I've built many rear hubs/axles/wheels for a variety of spacings to accomodate different frame widths and different freewheels.

I am glad you mentioned that; if this works and I do a couple more conversions, #3 has Suntour Superbe hubs.

The game plan is evolving: (a) get the freewheel, (b) build out the drive side of the axle just enough, (c) then add enough on the non-DS to get the desired OLD, (d) only then cold-set and re-dish the wheel.

So this might mean a bunch of spacers, It looks like Wheels manufacturing sells an assortment, a bit $$$ but if I am doing several bikes — worth it?

OK, I’ll look for that too. No fenders on this one, no claw.

Well, I’ll plan on the expense of a new axle, and be thrilled if I avoid that.

OUCH! It sounds like the avocet-dubbed wheels are no go. Then again, I do have a spare set of 700C wheels, Campagnolo low-flange hub that I suspect are early 1980’s (the hub has a bulged center); I could swap around and 1980’s hub should be OK as the frame is 1988 even if the componentry is older Record/Nuovo Record.

All very interesting, thanks. Again, this give me flexibility but I’ll shoot for a couple of mm each side.

I was planning on that once there’s something to show. Right now the Masi sits in the garage, dusty and unridden in two years — I got lazy and stopped trying to track down a non-DS crankset (?) creak, now I’m going to attack that with fervor as part of the conversion.

repechage

Masi dusty and not being used?

tiger1964 

Hmm, I dragged out those alternative wheels. Looking at Velobase, the hubs are likely Campagnolo Record C and the OLD is (kinda hard to get the micrometer in between the spokes) is 126mm. Hey, perhaps getting easier? However, the rims are something labeled Matrix IsoC and are semi-deep-V and a medium gray finish, much more modern than I am used to. But, perhaps not too inappropriate on what is purported to be a 1988 Masi Gran Corsa? And I need to measure the frame... it might already be 126mm OLD, or wider.. so no cold-setting?

All that said, if this works, I'll also do my wife's Windsor Pro, she could really use the electric shifting... and I know that has traditional Record hubs, so all this is valuable.

Yeah, I got lazy once the crank squeak started. I'll try to make up for lost time.

Wildwood

Is ANY amount of freewheel 'wobble' acceptable - assuming wobble is from bent axle.

bulgie 

No, bent axle cannot cause wobble, because the axle is fixed in place, not rotating (by definition! If it rotates, it's a spindle.)

Wobble in the freewheel is cause by the freewheel 9 out of 9 times. I've never know it to cause any real problem. Try a different FW if it bothers you.