Gear

Technical FAQ with Lennard Zinn: Chain Wrap Compatibility

Dear Lennard Zinn;My question has to do with Campy Record 10-speed rear derailleur and cog compatibility. My current setup has 53x39 chainrings, a 12x25 cogset with a short (standard) cage rear derailleur, and I recently switched to a Wipperman 10-speed chain. For mountain riding, I would like to substitute a cogset with a larger inside cog - say, 26 to 29 teeth - rather than switching to a triple chainring setup. How high can I go before I have to use a medium or long cage derailleur? Also, for cost considerations, is there any problem using a Chorus 10-speed cogset if the rest of the

Dear Lennard Zinn;

My question has to do with Campy Record 10-speed rear derailleur and cog compatibility. My current setup has 53×39 chainrings, a 12×25 cogset with a short (standard) cage rear derailleur, and I recently switched to a Wipperman 10-speed chain. For mountain riding, I would like to substitute a cogset with a larger inside cog – say, 26 to 29 teeth – rather than switching to a triple chainring setup. How high can I go before I have to use a medium or long cage derailleur?

Also, for cost considerations, is there any problem using a Chorus 10-speed cogset if the rest of the components are Record?

Dear Reader;
To figure out many derailleur capacity problems, you need to know how to compute “Chain Wrap Capacity”.

Chain Wrap = (large chainring – small chainring) + (large rear cog – small rear cog)

So, for you that would be: 53 – 39 + 29 – 13 = 30
Or: 53 – 39 + 26 – 13 = 27

Campy Record and Chorus 10-speed double rear derailleurs are rated to a maximum of 26 teeth on the largest cog, and a total chain wrap of 27 teeth. Chorus and Record medium-cage derailleurs and all Centaur and Daytona 10-speed rear derailleurs are rated to a max cog size of 29 teeth and total chain wrap of 30 teeth.

So, you can use a short-cage derailleur with the 26T or a medium-cage with the 29T. –Lennard

The answer from Campagnolo:
Probably you already know that 10-speed rear derailleurs are available on three versions: short, mid and long cage. You must use:

Short cage with double crankset with 11-21, 11-23, 12-25 and 13-26 sprocket combinations.

Mid cage double crankset with 13-29 sprocket combination and triple crankset with 11-21, 11-23, 12-25 and 13-26 sprocket combinations.

Long cage triple crankset with 13-29 combination.

With reference to compatibility question about the use of components from different groups, I can say that they are full compatible. You can use Record components and Chorus components together.
–Joseba Arizaga
Campagnolo Italy

Dear Lennard Zinn;
My Mavic Ksyrium wheels have over 15,000 miles are true as new. But the freewheel ratchet is getting a bit stiff. On the workstand, spinning the rear wheel by hand also makes the crank spin around. It’s not all that stiff, but it’s sure stiffer than it used to be.

I’ve been doing my own work for 20 years, but I can’t figure out how to get any lube into the freewheel, much less how to actually open it up. The Mavic website was no help. How can I get some slippery stuff in there? Just spraying lube in each end of the cassette body doesn’t help. And what sort of lube should I use?
–Doug

Answer, from Mavic:
To clean and lubricate the freehub body on any Ksyrium, you will need a 5mm and a 10mm Allen wrench, some light weight oil (such as Mavic mineral oil M40122). Remove the axle end cap on the non-drive side by pulling it out.

Insert the 10mm Allen wrench in the non drive side of the axle and the 5mmAllen in the drive side and loosen counter-clock wise, unscrew and remove.Turn the wheel on its side, freewheel side up. Paying attention to the pawl springs (they can go for a flyer) rotate the body counter-clock wise and pull up, and remove. Clean the pawls, springs and hub shell. Replace springs and pawls, put 10-20 drops of oil into the freehub and reassemble.
–Chris Zigmont
Mavic USA

Dear Lennard Zinn;
Here’s a question for you – me and my friend have no idea what it’s about. We’re ignorant, but if this question is stupid, just ignore. Thanks for the great articles.What is the purpose of after-sale frame alignment, especially on new frames? A few years ago my friend bought a Litespeed from a LBS and they told him that it needed to be aligned and balanced using their special table (for a fee). He called Litespeed and they told him it wasn’t necessary, and he didn’t do it. It’s ridden just fine ever since. I think one of the VeloNews bike shop advertisers also offers a pre-shipping alignment service, but how do you align a carbon, lightweight aluminum, or titanium frame? Is this a hoax for more dollars, like those undercoatings new car dealers try to sell you? I can see realigning my steel frame and fork after a horrific crash, though if it came to that, I’d probably toss it.
–Michael

Dear Michael;
Steel and titanium frames that are mildly off can be aligned, but not aluminum or carbon ones. Same goes for forks.

Pre-shipping alignment of new frames sounds like a crock to me. A new frame should be straight to start with or you should send it back! (The kicker to this is that you would have to be able to determine if it is off. You would need some alignment tools to do that. However, you can do a lot with a string. Details of checking alignment with simple tools are in ” Zinn & the Art of Mountain Bike Maintenance” and “Zinn & the Art of Road Bike Maintenance.”)
–Lennard

Follow-up on stuck seatposts:
1. An added comment regarding your stuck seat post article: I have a titanium Merlin XLM that also had a seized post. I tried everything to get that thing out. I soaked it for days in all directions with penetrating oil and nothing helped. The manufacturer wanted a large sum of money to extract the post, so I brought it to my shop. The wizards at CK Cycles in Albany, New York, Larry and Jeff, packed the seat post with snow. The post contracted and was removed with absolutely no damage to the frame. The magnesium sleeve in the seat tube was not even damaged. Necessity is truly the Mother of invention.
–Dave Spore

2. Seal all holes in bottom bracket. Turn bike upside down. Remove water bottle screw and with straw put Root Beer in tube until full. Make sure soda stays in frame and is not dripping out from seat post. Replace screw. Let bike sit upside down overnight. Next day, seat post will come out. B&L Bikes did this for me, I witnessed the whole thing, and it worked.
–Michael

3. One solution I’ve found to work for stuck seatposts (after the large bench vise failed) is a pipe wrench used in conjunction with a breaker bar (long pipe). What I did is to lay the frame on the floor and positioned the pipe wrench on the post so that I could work against the main (front) triangle. I then slid the pipe over the handle and applied my weight to the wrench. It took a little bouncing and the post made a pretty sickening noise when it finally broke loose, but the frame (which was steel) was unharmed. I then went back to the bench vise, reclamped the post and, over time, worked it free by twisting and lifting the frame.

I would never use this process on a super lightweight frame but found it preferable to trying to use the bare hacksaw blade method. I was unable to tell if the hacksaw blade was actually long enough and was a little worried about cutting into the seat tube. Obviously, anything short of hiring a professional machinist is risky. I just thought I’d mention a procedure that worked for me.
–Jeffrey Warren

Follow-up on availability of long mountain cranks:
1. Reading your comments and Shimano’s about cranks/bb interface failure, I had a related question: I’ve seen Race Face cranks advertised in up to 180mm lengths, with either square or Isis spline interface. It seems like the longer spline interface of Isis might be advantageous, as it seems like the Shimano interface can wear if it works loose. Still, it’s an expensive thing to try, but at least it’s a 180 other than XTR.
–Ian

2. You asked about non-custom mountain cranks in 180mm lengths. I believeMiddleburn in the UK will happily supply 180mm cranks, check-out www.middleburn.co.uk. They also do road cranks.
–Angus.

3. With the demise of Syncros I think one of the only non-Shimano mountain cranks that come in 180mm are RaceFace turbine cranks. I believe they are available from QBP as cranks with no chainrings.
–Brian

4. Profile Racing tubular steel cranks (now called MTB DOWNHILL 3-PIECE CRANKSET) are available in 160mm-190mm lengths, 48 spline spindle (steel or Ti), 4 cartridge bearing BB, adjustable chainline, 110 or 94 triple spider.Not light but bullet proof.
–Don

Dear Lennard Zinn;
Hi Zinn. I am a 6’5 230 lbs rider using 175 cm cranks. Would 180’s or bigger be more suitable for me? I am a 40 yr old, mostly recreational rider, logging between 4 and 5 k per year?
–Biagio

Dear Biago;
From my own experience (same height) I would try 200mm cranks, if I were you.–Lennard

Follow-up on creaking BBs:
1. I have found that the best way to eliminate creaks in Shimano BB’s for the longest period of time is Canola oil. It works much better, and lasts longer than either heavy grease or plumbers tape (I have tried it all). I have two Ti bikes (notorious for BB creaks) and I have found just plain old Canola oil eliminates the creaks for good.
–Chris

2. And, to revisit some of the creaking subjects we visited here a few months ago: I have spent a lot of time chasing creaking cranks, greasing and teflon taping various connection points, only to discover that the creaking was coming from a seatpost/frame or seatpost/saddle interfaces.

It often seems like the cranks because it generally occurs while you are pedaling. You may be able to isolate the source by standing and pedaling. If it is still creaking, it is probably the crank/bottom bracket. If it goes away when standing, grease the seatpost, clamp, bolt, saddle clamp and rails.
–Beau

PowerCranks’ founder comments on my answer to a question last week:
The proper way to use PowerCranks for the optimum benefit is somewhat controversial. Many coaches believe as you do that regular cranks need to be used regularly to maintain full power for racing. Others believe as I do that PowerCranks should be used exclusively to maximize the benefit. I am sure there are others with other ideas also.

This question should be answered in the next season as I know of several professionals (both cyclists and triathletes) who are intending to race on the cranks. Based upon their performance in races we should be able to determine if racers are faster, the same, or slower when racing on PowerCranks than they would be expected to be if racing on regular cranks. I believe we will find they are significantly faster and I believe you believe as you do because you evaluate so much equipment that you couldn’t give them enough time to get through the transition period necessary to get back to putting full power on the downstroke.

The other issue you failed to mention (which is only applicable to the triathletes) is what they do for running speed. This benefit for the triathlete is, perhaps, more dramatic than the cycling improvement, it certainly happens much faster. There was a recent independent evaluation of this aspect of the PC’s done by a world-class sprinter (Aaron Thigpen) at www.gamespeed.net should you need more than my own opinion.

How to best use the PowerCranks and their full potential still remains unknown and controversial. We will know much more with time and experience.
–Frank Day
PowerCranks founder

Follow-up on recent discussions of Campagnolo chains:
Dear Lennard Zinn;
Do have any thoughts on using a Super Link to join a Campy 10-speed chain. Is this a viable option, or something you would not recommend using?
— Steve

Dear Steve;
We asked our favorite Campy specialist about that one. See below:–Lennard

From Peter Chisholm:
Just a note about 10s chains, non-Campagnolo. Both Wipperman and IRD make really nice and functional 10-speed chains. Both come with ‘masterlink’ type snap links. The Wipperman is pricey, more than a standard Campagnolo one but the IRD one is not ($25 retail).

In addition, we recommend using the Campagnolo 10-speed chain but replace the permalink or new ‘pin’ system with an IRD snaplink. It retails for $8 and is re-useable.

Both chains are readily available from Quality Bike parts or Merry Sales.
–Peter Chisholm
Vecchio’s Bicicletteria
1833 Pearl St.
Republic of Boulder
www.vecchios.com


VeloNews technical writer Lennard Zinn is a frame builder, a former U.S. national team rider and author of several books including the pair of successful maintenance guides “Zinn & the Art of Mountain Bike Maintenance” and “Zinn & the Art of Road Bike Maintenance,” and “Zinn & the Art of Triathalon Bikes.” Readers can send brief technical questions directly to Zinn.