Author Topic: Respacing a Campagnolo Record Pista hub  (Read 523 times)

Respacing a Campagnolo Record Pista hub
« on: March 14, 2019, 01:46:04 pm »
These have the "standard" (not really) Campag track chainline of 42.5mm.  I want 46mm to match my other wheels, although I'd settle for 45mm.  The problem is that there are no spacers to move from the RHS to the LHS.  I can move the lock washer and grab about 2mm (44.5mm chainline) but I need slightly more.

Any suggestions?  Are there any shorter Campag cones or thinner locknuts that will work?
Never tell me the odds.

Re: Respacing a Campagnolo Record Pista hub
« Reply #1 on: March 14, 2019, 01:49:46 pm »
a suggestion;  use the correct (track) chainline for fixed, if you want to use proper kit. 46mm is not the correct chainline.

cheers

Re: Respacing a Campagnolo Record Pista hub
« Reply #2 on: March 14, 2019, 03:32:19 pm »
£80 for new Andel* cranks, 144BCD rings and BB...plus junking some £200 Goldtec wheels!

There's no real track standard - the most expensive stuff like Campag, DA and Sugino 75 clusters around 42 or 42.5mm but there is tons of stuff from 44-46mm.  Miche hubs are 42ish but are best respaced for 46mm as this eliminates wheel dish.

*cheapest 42mm cranks I know of, but poor heel clearance (as with most 42mm cranks).
Never tell me the odds.

DaT

Re: Respacing a Campagnolo Record Pista hub
« Reply #3 on: March 14, 2019, 04:17:20 pm »
£80 for new Andel* cranks, 144BCD rings and BB...plus junking some £200 Goldtec wheels!

There's no real track standard - the most expensive stuff like Campag, DA and Sugino 75 clusters around 42 or 42.5mm but there is tons of stuff from 44-46mm.  Miche hubs are 42ish but are best respaced for 46mm as this eliminates wheel dish.

*cheapest 42mm cranks I know of, but poor heel clearance (as with most 42mm cranks).
Paul componests admits that his chainline is "wrong" and the standard is 42mm.
http://www.fixedgeargallery.com/reviews/paul/
Quote
Dennis: I realized that your chainline is different too, how'd that come about?

Paul: The 44mm chainline is from pure ignorance. When I did the first ever mtb single speed hub I just pushed the freewheel out as far as I could so the wheel would be as strong as possible. This is how 52mm came to be considered the "normal" chainline for single speed mountain bikes.
So I did the same thing with the fixed hub and it turned out to be 44mm. After looking at other fixed gear hubs I concluded this would be close enough. Turns out that God, or some other higher being invented 42mm and we have been in hot water for this great sin ever since. This is one reason for us to do the crank. I could have just changed the hubs but I liked them the way they were, and I have a rebel streak anyway.
I do understand not every company does use 42mm but they are the exception.

Re: Respacing a Campagnolo Record Pista hub
« Reply #4 on: March 14, 2019, 04:58:07 pm »
I don't know if you can get anywhere by using a different sprocket.  Sheldon lists various sprocket widths (and hub dimensions) here:
https://www.sheldonbrown.com/chainline-single.html

I'm running a 44mm (ish) chainline as I could do it a lot cheaper than 42mm (would have needed a new, super narrow BB and a more expensive chainset). I've got locknuts on (halo and system X hubs) so I'm Ok with the number of spacers I needed - I assume you've run out of spacer wiggle room and are concerned about stripping the threads on the hub?

Re: Respacing a Campagnolo Record Pista hub
« Reply #5 on: March 14, 2019, 06:46:17 pm »
it is not at all difficult to set up almost any square taper crankset to give a 42mm chainline.  The inside position of a road double is often about 42mm chainline anyway; if not a thin spacer behind the RH cup will make it so.  A shorter BB axle and a bit of crank modding allows the use of a road double chainset with a single ring at 42mm chainline in the outer position.

 Lasco cranks are cheaper and have better heel clearance; the only real reason for buying Andel is that they use 144mm BCD chainrings (sort of).

If you have hubs that gives a ~46mm chainline just turn the sprocket round and it will come out very close to 42mm...?

As it happens a 42mm chainline works out nicely in several respects

a) you can buy proper track hubs and you don't have to ruin them to get them to work
b) if you take a 'road' type hubshell, build it dishless with a solid axle, fit a singlespeed freewheel, and it usually works out about 42mm chainline
c) if you do as per b) and fit a fixed gear sprocket with a 1.6 or 2mm spacer, again this works out about 42mm chainline. If you have two brakes (which you should do on the road, really) you don't need a lockring on the sprocket.

FWIW many 'flip-flop' hubs give a chainline about 40mm, so really are meant for an adapted road bike, using a single ring in the inside chainring position of a double.

cheers

Re: Respacing a Campagnolo Record Pista hub
« Reply #6 on: March 14, 2019, 08:47:29 pm »
I'm already on a 103mm BB. TA track cranks are 46mm chainline.

I'll move the lock washer, which never works anyway, and the EAI sprocket grabs another 0.27mm compared to a Campag one.  That gets me to about 44.6mm, which is close enough to set the chainline in between; < 1mm error is what I aim for.

Out of interest, do you check chainline with a 2' steel rule?  Just measuring front and rear chainline is pointless as frames are often up to 4mm out.  Buying £500 worth of matched Campag track components can still give you lousy chainline, something Sheldon never emphasised enough.

Never tell me the odds.

Re: Respacing a Campagnolo Record Pista hub
« Reply #7 on: March 15, 2019, 04:34:25 am »
I'm already on a 103mm BB. TA track cranks are 46mm chainline.


which model cranks are you using?  FWIW if a single ring chainset ends up ~45 or 46mm chainline, this is usually because it is really one designed for derailleur gears. 120mm/5s chainline is ~45mm.



Quote
Out of interest, do you check chainline with a 2' steel rule?  Just measuring front and rear chainline is pointless as frames are often up to 4mm out.  Buying £500 worth of matched Campag track components can still give you lousy chainline, something Sheldon never emphasised enough.



If you want a really good SS setup there is no point in nailing parts onto a frame without checking it first.

1) check the BB shell is square (it sometimes isn't). Lay a straight edge against the chainring (so that the inclination is the same as the top tube)  and compare it by eye to see if it is parallel or not.  If it isn't, get another frameset.

2) check the track of the frame. You can do this using a length of thread, running from one rear dropout to the head tube, around that, and back to the other rear dropout. Compare the clearance to the seat tube each side.  Correct accordingly.  If you have a good eye, you can 'sight' the head tube, seat tube and dropouts from the front; no thread required.

3) check the dropouts are at a uniform height, and there isn't a 'tilt' to the rear wheel.  To do this fit a good rear wheel, and (with the bike laid down) lay a straight edge on the wheel so that the inclination  is the same as the seat tube. Compare and see that the two are parallel.  If they are not, double-check that the wheel is parallel to the top tube; if it isn't, this will cause a small tilt error with track dropouts.  Tilt errors are difficult to correct, but fortunately are also fairly rare and don't really affect how well a SS setup runs, mainly how well the bike steers.

Needless to say if the frame is even slightly out of track or the wheel is not correctly dished, the rear wheel will likely be slightly skew WRT to the centreline of the bike; this will result in poor running, as if the chainline is wrong, even when it isn't.

You can run whatever chainline you like when all is said and done, but if you want to use proper track equipment, e.g. campag pista hubs, without a lot of aggro, best to stick with a 42mm chainline. No need to spend a fortune on parts to give a 42mm chainline if you don't want to, you can get a 42mm chainline with less expensive parts easily enough.

cheers

Re: Respacing a Campagnolo Record Pista hub
« Reply #8 on: March 15, 2019, 06:43:42 am »
I don't know if the bike mags actually do proper testing any more.  C+ (before it was crap) used to check frame alignment and rear triangles were frequently +/- 4mm off.  On derailleur gears this causes little problem, as the frame will ride normally, but on a fixie it's disastrous, if you've already bought a track groupset.

Taiwanese frames are probably straighter than handbuilt British frames.  Steel frames usually distort during brazing and have to be cold set at the end.  If the frame was within the fairly generous tolerances, they'd just let it go.
Never tell me the odds.

Re: Respacing a Campagnolo Record Pista hub
« Reply #9 on: March 15, 2019, 10:44:37 am »
You can respace if you go to 126 or 130 for the rear end. You'd need a longer axle (hollow or solid) and spacers/washers.

The 42mm chainline is actually standard, for a 120mm hub. Unless you have a narrower cone, no washer, the hub shell can't move any further to the right. And in any case is there even enough of a gap between the sprocket and dropout to move the hub shell to the right by 4mm? The 146 chainline I suspect came about because of conversion where people were using road parts.

Re frame alignment, I would have thought it's the height of the dropouts that's more critical, if that's out then the wheel won't be vertical. And no amount of "cold setting" after frame building will correct that. But having the dropouts at different height won't affect chainline I would have thought.

If the rear ends are not equally space from the bike centreline, then that would affect chainline but that is easily sorted by bending the stays.

Re: Respacing a Campagnolo Record Pista hub
« Reply #10 on: March 15, 2019, 10:54:08 am »
….Taiwanese frames are probably straighter than handbuilt British frames....

that's not been my experience.  FWIW when C+ measured track errors, any importer worth a light would obviously check this before supplying a test bike to the magazine, so after a while 'they were all straight' more or less....

 Mind you, if you are looking at an old frameset, then anything can have happened to it. If the back end has been clumsily reset from 120mm to 126 or 130mm  it isn't unusual for all the movement to occur in the RH (dimpled) chainstay….

cheers
cheers

Re: Respacing a Campagnolo Record Pista hub
« Reply #11 on: March 15, 2019, 09:04:10 pm »
Got almost 45mm by moving the locktab washer and with an EAI sprocket.  A small gain in chainline from the sprocket (EAI vs a Campag sprocket, on which the 42.5mm is based) and the rest from the washer.  That's close enough for compatibility and improves wheel dish a bit.  Also easy to reverse, although that becomes somehat more tricky once it's built into a wheel!
Never tell me the odds.

Re: Respacing a Campagnolo Record Pista hub
« Reply #12 on: March 16, 2019, 01:55:55 pm »
looking through my collection of fixed sprockets, I noticed that an old 1/8" Villiers sprocket (which IIRC I'd used on narrow flip-flop hub) was also offset more than normal, i.e. with about +2mm offset from the usual position, mostly by dint of the RH face of the sprocket being dished. I used it on a narrow hub to bring the chainline out to ~42mm but you could equally well use one to bring the chainline out to 44 or 46mm on a suitable hub.

cheers

Re: Respacing a Campagnolo Record Pista hub
« Reply #13 on: March 16, 2019, 01:58:45 pm »
FWIW I used to have a Phillips double fixed hub that was 38mm chainline. I was a spotty youff at the time and could never work out why the chainline was miles out when flipping the hub (which I did habitually). (This was pre-internet days so no YACF to correct me at the time.) I think 38mm must have been a sort of pre-war standard because my (continental) Super Champion dérailleur (Osgear to Brits), which is 1937 pattern, also uses a 38mm chainline for the tensioner pulley (and doesn't tolerate a big variation - it can unship the chain back pedalling if the pulley isn't vertical).

Re: Respacing a Campagnolo Record Pista hub
« Reply #14 on: March 16, 2019, 02:07:45 pm »
Just tried the hub in the frame with a straight edge on the chainring.  It's only about 0.5mm adrift from the other wheels. I have thin spacers for under the RH BB cup to optimise for one or the other.  The tub wheels have an alloy sprocket* so that probably benefits most from perfect chainline due to its relative softness; even with a bushingless chain, which masks most chainline errors, iffy chainline preferentially wears one side of the sprocket.

*VeloSolo - impressively quiet, although I don't think I'd use one for gritty commuting.
Never tell me the odds.

Re: Respacing a Campagnolo Record Pista hub
« Reply #15 on: March 16, 2019, 03:06:06 pm »
before derailleur-geared bikes became popular, there was basically not much  point in having a back end any wider than about 4-1/2".  Hence you could fit a SS or a SA 3s gear in and that was good enough. Chainlines around 38mm were not uncommon. To this day you can build a SA 3s hub to about 4-1/2" OLN if you want to, and yes the chainline can be around 38mm if you need it to be, and that was not uncommon on roadster models that could be configured to accept a SS or 3s gear.

 That there was a good deal of variation in chainline is evident in the design of the splined SA AW driver (circa 1938); it had 2x 1/16" spacers and in addition could use a dished sprocket, giving a possible chainline adjustment of about 1/4" at any one OLN configuration. That the chainline drifted out as time went on is also evidenced by the fact that SA increasingly made longer axles, but they were (for a long time) only made longer on the left side; this implied that any increase in OLN would usually be accompanied by an increase in the chainline measurement.  On the continent some roadsters still use a narrow rear (coaster brake) hub and a chainline around 38mm.

The de facto track standard kit hails from when most frames were built 120mm OLN. In later years it became more normal to have a special bike for SS use, but there has (and always will be) SS kit which is designed (by chainline and/or OLN) to be compatible with whatever readily available road bike stuff is contemporary.

cheers

Re: Respacing a Campagnolo Record Pista hub
« Reply #16 on: March 16, 2019, 05:22:26 pm »
Older track hubs are 110mm but I've never seen one.
Never tell me the odds.

Re: Respacing a Campagnolo Record Pista hub
« Reply #17 on: March 16, 2019, 05:57:40 pm »
I had a 'Hill Special' road/path from the early 1950s and that came with a selection of mostly British kit on it. I still have the LF airlite hubs, and the rear is  narrower than 120mm.

cheers

LittleWheelsandBig

  • Whimsy Rider
Re: Respacing a Campagnolo Record Pista hub
« Reply #18 on: March 16, 2019, 08:42:32 pm »
NJS rear hubs are (or were) 110mm.
Wheel meet again, don't know where, don't know when...

Re: Respacing a Campagnolo Record Pista hub
« Reply #19 on: March 17, 2019, 08:00:20 am »
NJS rear hubs are (or were) 110mm.

I didn't know that. I looked and it seems you can get 110mm and 120mm hubs with NJS marks.   I've never been terribly interested in NJS equipment per se; I understand that you need it if you want to go NJS racing, but otherwise it seems that folk covet the NJS mark such that identical parts with the mark are worth much more money than those without. This is slightly more crazy than even the usual 'collectors' mindset, and that is bad enough.... :o

cheers

Re: Respacing a Campagnolo Record Pista hub
« Reply #20 on: March 17, 2019, 09:01:31 am »
NJS saddles also have narrow rail spacing.  Kashimax NJS saddles sometimes come up cheap on fleaBay but a seatpost to fit them will be very expensive and will probably need to come direct from Japan.
Never tell me the odds.