Technical Q&A with Lennard Zinn

By Lennard Zinn

Dear Lennard Zinn;
We’ve been looking around for a good road bike for my girlfriend andone thing we’ve noticed is that the Shimano STI shifters do not fit herparticularly well. She has relatively small hands and the levers are justtoo far away from the bar for her to comfortably brake. I believe thatShimano addressed this issue in the mountain bike brake set up, but dothey or anyone else address it in the road arena? –MikeDear Mike;
There is no alternative, short brake lever from Campagnolo or Shimanowith an integrated shift lever like ErgoPower or STI in it. You can addressit with the handlebar. Here are some options below.
–LennardAnswer from Cinelli:
Our 3T Eva handlebar has been specifically designed for women. Thanksto the specific drop design the distance between brake levers and the baris reduced (compared to standard handlebars) to permit safe braking action.
See the attached Eva picture and description.
–Riccardo Carpinacci
R&D Engineer, CinelliAnswer from Deda:
The Deda shallow-shape bend in the handlebar, available for Newton,215 and 4Girls models. The round, short radius lets you to have your handcloser to lever.
Fulvio Acquati
Deda ElementiStrong men need strong cranks
Dear Lennard Zinn;
OK I am a 6 foot 8 inch 265 pound rider, I am ridding with Campy Record180mm Cranks where can I find out more info on 200mm or longer cranks andhow strong they are. I am a 44-year-old Fast Club rider, logging about6500 to 7300 miles a year. I eat rear wheels and chains about every 4 to6 months, No flex and strong cranks are important to me. I had a few Campycranks break on me in sprints and believe me it is no fun. –TedDear Ted;
High Sierra Cycle Center, at www.hscycle.com,makes them. I think they are quite strong. I have made a lot of bikes withthem for guys as big as you, and nobody has had a single problem. HighSierra claims to have tested them to very high loads. — LennardIncreasing the Q
Dear Lennard;:
One of your recent discussions regarded arthritic hip pain. One ofthe responses (I’m not sure if it was you or not) mentioned using pedalspacers (2.5 mm) to increase the Q factor. I’ve been searching ever sincefor a source. I’m sure I could cobble up something but would like to usesomething engineered for the purpose. I work in a bike shop and couldn’tfind a supplier. Any info would be a big help. –GeorgeAnswer from Andy Pruitt, director of Boulder Center for SportsMedicine:
In the clinic we use plain washers from the hardware store, in severecases, we get the Knee Saver from Randy Ice in California.
–AndyFollow-up from the discussion of draftingfrom the front (aerodynamic assist from having a rider behind you):A motorcyclist’s theory: The response to your reader’s questionabout lead riders benefitting from a counter draft was interesting. Inaddition to racing bicycles, I road raced motorcycles for seven years.I have no background in physics, but at higher speeds having somebody behindyou is a clear detriment.If you are riding down a straightaway at speed (~150 mph) with somebodyclosing in on you, you can literally feel a rearward tug as they move intoyour slipstream. For the person in the rear, there is a vacuum effect thatlets you momentarily go faster than your gearing allows, making it possibleto slingshot past the person in front.I’m guessing the physics here are different from what happens at bicyclespeeds, but it’s interesting to know that having a ‘rear drafter’ has oppositeeffects for the two disciplines.Something I’d be interested in hearing you cover is cornering. Conventionalbicycle wisdom dictates that you push the bicycle down into the turn whileleaving your body slightly more parallel to the ground. In motorcycle racing,the opposite holds true; you hang off the bike to get closer to the ground,allowing the motorcycle to to remain more upright, providing a fatter partof the tire to remain in contact.I won’t say that current bicycle cornering dogma is incorrect, but Iwill say that in hilly races with curvy descents, I can pretty much passpeople at will. Whether this is due to my ‘unique’ cornering style or ifit’s simply because I’ve studied cornering on and off road, motorized andnot, is not something I’m clear on. –PeterAerodynamicist Chester Kyle, designer for of 1984 and 1996 Olympicsuper bikes and aero’ equipment, responds:
As far as Peter’s observation, if a motorcycle approaches from theside and slingshots past, I believe he may be correct, the drag on thelead motorcyclist could go up (I don’t know this for sure). However, ifa motorcyclist follows directly behind on a straight road at the same speed(not accelerating), the bow wave from the following motorcycle will raisethe pressure on the back of the leader and actually lower the drag of theleader.Likewise the draft from the leader will lower the drag on the follower,so they both will benefit. Think of the coupled cars on a railroad train- the air drag is basically surface friction, not pressure drag. Race carsdo this all the time on a track, forming a tandem bumper to bumper teamto blow by the field.Interestingly, if you bicycle closely in front of a following auto,the bow pressure wave from the auto will create an artificial buoyancyon your body that will give you a boost much like drafting. Try it sometime. The effect of a following cyclist or motorcyclist is similar, butof much lesser magnitude. You probably can’t detect a cyclist on your wheel- I never could. — ChesterFollow-up on Campy chains:
Re the question about master links and campy chains: I’ve beenusing the Connex link with a Campy chain and also a Connex 10sp chain.I like the Campy chain better and have not had any problems with the Connexlink, which works really well.I’ve broken one Campy chain with the Permalink. I don’t know if it waspoorly set up, but expect not because the mechanic/frame builder was DarrylMcCullough who is one of the best in Australia. I’ve also broken a Connex10-speed chain, but not at the joining link, which is now doing sterlingduty on another chain. –PeterRegarding removing a stuck seatpost:
1. I just saw the recommendation for packing stuck seatpostswith snow and thought I’d add my $.02.I am a former shop rat, and a sister shop rat shared this techniquewith me back in the era of friction down tube shifters. Probably owingto our lack of testosterone and the accompanying brute force mentality(i.e. hacksaws are not cool, they are merely dirty, destructive and onemight actually break a nail using one) our preferred m.o. was and is toemploy simple high-school physics just as the CK Albany fellows did.Here’s my version: Gently warm the seat tube (head tube if dealing witha seized quill stem) with a hair dryer. When the outer component becomeswarm to the touch, take any standard CO2 inflater and deploy a full cartridgedown the seatpost (or into the base of the fork) to cool the inner component.Voila’!If you don’t have an inflater, or it isn’t feasible to deploy the coldCO2 in close enough proximity to the inner component, then packing it withsnow or crushed ice is a fine alternative. Care should be taken to completelyclean and dry all surfaces before re-lubing when using the ice/snow methodor you will merely re-create the oxidization weld.In the course of a decade of dealing with my own and friends’ / clients’bikes, I have yet to employ a hacksaw, breaker bar or other potentiallydestructive method to release a stuck stem or seatpost. This practice hasproven especially effective for dealing with carbon seatposts which dostick, and are generally too delicate and pricey to risk clamping or wrestlingwith.–Beth2. – Electronics stores stock a spray which supercools whateverit hits – they use it to diagnose components that fail when cold. Thiscould be a good alternative to snow in the seatpost, especially if youcarefully heat the frame (i.e., by pouring boiling water on it.) In placeslike Houston, snow is a pretty rare commodity, even though the LBS herecharge like they keep it in stock.The guy using a cheater bar and monkey wrench to break his seatpostloose is a lunatic!!! He may have gotten lucky once, but in time something’sgonna give…Old mechanic’s trick – soaking frozen nuts and threads in brake fluidfor a day or so. It will tear up paint, so don’t use if you have a paintedframe, but brake fluid is a really nifty penetrating oil if carefully used.–Dave