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Stuck in gear and need expert advice? Ask Andy the Mechanic (a.k.a. Andy Wallen), the proprietor of Wheelcraft Bicycles of Wheeling, WV. (Please, no old bike & antique questions.) E-mail to ibike@bikexchange.com, subject "ask the mechanic," or mail your question directly to Ask the Mechanic, c/o Wheelcraft Bicycles, 2185 National Road, Wheeling, WV, USA 26003. Andy will e-mail your advice and we may post it afterward. Take a look at our back issues to find answers to all kinds of bike fix-it questions.

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How To Rock and Roll : A City Rider's Repair Manual
by Sam Tracy

Fall 2001 Questions & Answers (40 of them)  ...


I've got Gripshift trouble.

Funny you should ask, but yes, I am stuck in gear--or at least my bike is.

It has Grip Shift shifters and the front derailleur is stuck on the largest sprocket.  I applied more than reasonable force, but the shifter will not turn.  The shifter model number is MRX200-10 and the problem is in the shifter (cable and derailleur are OK).  I took the shifter off the handlebar and pulled it apart and was pleased to find that it is very simple (simple is usually good), and has only three main parts: inner housing, outer housing and a flat steel (stainless, I think) spring.  I don't see any damage inside and I would like to put it back together to see if it works now, but I can't figure out how to compress that spring so that the part of the outer housing that it normally contacts can slide past it.  I thought about drilling a hole in the outside of the "inner housing" (my name for the part that clamps on to the handlebar) and compressing the spring with a rod through the hole, but there may be a better way that I am not seeing. The shifter must be disassembled and reassembled to replace the cable and cables must be replaced occasionally so this shouldn't be a big puzzle, but it is for me. 

What's the secret?  How do you reassemble this thing?  

Thank you in advance,


You must have the spring in the exact position that it was in when it came out--usually with the open end towards the rear of the bike. Then slightly twist and press the shifter into place.  The starting point is at one extreme of the shift range, i.e.; the highest or lowest gear, depending
upon the year and whether it is left or right. Do not compress the spring. SRAM is very good about customer service.  Try their website at www.SRAM.com.


Hi Andy,

I just bought a Univega Alpina S7.7 and was wondering if you had any info on it? I can't seem to find any anywhere.



I don't deal with Univega, which is part of the rapidly declining Derby group--Diamondback, Raleigh. The world is crawling with Derby dealers, they shouldn't be too hard to find.



Subject: Horrible Clicking Noise

I'm not sure whether it's the chain wheel, as the clicking noise seems to come from there. How should I solve this problem?



The most common sources of noise are: 1) lose crank bolts, 2) loose bb cups, 3) bad bb bearings, 4) loose chainring bolts, 5) pedals. The more stuff you have, like suspension pivots, add more possibilities, and don't rule out the chain.



I am used to riding an old Jamis Dakota '88 mountain bike. I want to do the AIDS ride next summer and am thinking I will need a road bike. Road bikes are a whole new arena for me. Never, ever rode one.

In looking at the gearing, I think I want to go with the three chainrings. Also I am working with a limited budget. Don't want to go over $1,200.

What manufacturers would you suggest?  Also I understand the Shimano 105 is the minimum I should look at.

I am a 53-year-old male, 6-foot in height, and I should be about 185 pounds by time of ride. Right now I'm hitting 195 pounds. Haven't been doing a whole lot of riding the past two years, but am psyched up to do this.

Please advise.

Thank you,


I may be wrong, but I think that the only way to get a 2001 bike with 105 is to compromise the frame.  Raleigh is famous (notorious) for out "spec-ing" everyone else, but you get a cheap Asian-made 7005 aluminum frame. If you must have 105, I'd look at closeouts rather than buy a cheap frame hung with above average components. No matter what, the frame is what is going to matter most. While I am usually staunchly pro-ferrous, aluminum is not such
a bad choice for a large frame size with a heavier rider, as you won't be as apt to flex aluminum stays and cause the rim to rub the brake shoes. For the long haul, steel is going to ride better. I am also staunchly anti-Asian at this price point.  Some of the best frames in the world come out of Taiwan, but if you have choices, as your budget allows, why not buy American? All Cannondale, Lemond, and Trek road bikes are completely U.S. built. Any other
brand could be, but probably is not.  A Lemond Buenos Aries is about $1,500--US built Reynolds 853 with carbon fork and Rolf wheels, which you could probably live without.



Please help. I am a heavyweight rider, carrying my 300 pounds on a Specialized
X-Roads A1 Pro.

I've already cracked the weak Ritchey Rock Comp on the rear. Specialized sent a
Mavic CXP21 as a replacement under warranty.

The salesman at my shop told me the Mavic touring rim T519, 36-hole, with a XT hub is the way to go to support my weight.

What rim/wheelset in a 700 x 28  would you suggest for someone my weight?



36 spokes is a good idea. If you're building a wheel and your biggest concern is strength, you could even go with 40 spokes. I've used a Bontrager Clyde 700c rim, and they seem pretty tough. The Mavic rim in question should hold up to 300 pounds with 36 spokes.

PS: You, and millions of much lighter people, can break anything under the right circumstances.


Is it possible to paint a carbon fork?

thank you,


In a word, yes, but don't do it, and don't let billybob's bodyshop do it.  Carbon fibre consists of  a carbon fabric (prepeg) and some sort of resin that sort of holds it together.  The pieces are basically glued together.  If you paint it with paint that contains certain volatile solvents, you could dissolve the resin and/or the glue joints.  Find somewhere than has experience with painting carbon, or a painter that uses powder coat.  While the best looking Kestrel forks are natural, they do offer forks painted to match their bikes.



I am using Campy and would like to know if I can use a Shimano hub and cogs? Are there spacers I can get?



There are various kits available that allow you to use Shimano with Campy and vice versa.  As far as I know, this is what's possible:

campy 8 to shimano 9
campy 9 to shimano 9
campy 8 to shimano 8
campy 9 to shimano 8



I own a Klein Pinnacle (circa 1988 with under-the-chainstay ubrake!); it has 6-speed rear cassette...

OK if you're done marveling/laughing that these dinosaurs still walk the earth...Is it possible to upgrade to a 9-speed and if so what parts would be required? Remembering that the frame is aluminum and therefore can't be altered as far as the width between stays...



I bet when you bought the Klein, the salesman didn't tell you that you should replace the frame every 5 years, did he?  Well, that's what the experts say, and I'm inclined to agree.  Now, I'm not suggesting that everybody who rides an aluminum mtn bike on pavement recycle a frame every five years, but aluminum has a very finite optimal (as in safe and efficient) life span, and for mountain bikes used for what they were intended, 5 years is about it--2 for handlebars and rims, etc.  You should not use any aluminum frame this old, so the upgrade is out of the question, and no aluminum frame, even a new one, should be spread.

Hi Andy!

A Giant AT-730  Hybrid bike that came with the Sugino Cycloid chainrings. I would like to  replace the egg-shaped rings with more conventional round rings. The set of  three rings are: 110/48T, 110/38T, and 74/28T. Is this possible? and what chainrings should I buy? I plan
on riding mostly rail-trail type surfaces. 

Thanks for your help,


You should be able to get exact round replacements for what you have.  If you're using a Shimano sis front shift system, I'd spring for the Shimano ramped rings.  Otherwise, I like the QBP engagement rings, which are a little cheaper and available with or without ramps.


Dear Mr. Wallen,

My name is Amy DeWitz and I need to know if you have any information or possibly some directions on how to build a velocipedes bicycle?  Not a full size one but a small model one.  I have to do this for a history project. The requirements are that is just has to work.  

thanks alot,
amy dewitz


Technically, a velocipede is a 2-wheeled bike with no pedals.  I think you may be looking at pennyfarthings (aka boneshaker, high-wheeler), which is a direct drive (like a tricycle) 2-wheeled bike with a huge wheel in the front.  If this is what you are looking for, I would buy a tricycle front wheel and go from there.  The trike wheel has the crank already attached, so all you'd have to do is devise a fork and rear wheel.  To scale, I'd estimate that the front wheel of a pennyfarthing would be about five to six times bigger than the rear.



I read through most of your posts regarding aluminum frames, but I can't find the post specifically addressing the aluminum drawbacks. Do you recommend steel over aluminum? Any particular steel? Since most bike manufacturers are going to aluminum, is that the way I should go too?



The biggest drawbacks to aluminum are:

  1. Limited lifespan (as in safe and efficient--app years for road bike)

  2. Not repairable--bend it it's

  3. Harsh ride, although some of the new stuff--altec2, Caad 4, 5, 6--has reduced this effect, at the expense of durability

  4. Ugly

There are situations where aluminum is the best choice, if you accept conditions 1 and 2.  If you are a big heavy guy, a steel or ti frame is going to flex a lot more than would aluminum.  Depending upon how big, heavy or powerful you are, this could be bad enough to render even the most prestigious of  steel or ti frames unrideable.  If light weight is more important than a long term commitment or comfort, you can not beat certain aluminum alloys--Caad 4,5,6, Dream Plus, Lemond Aeroaluminum.  Manufacturers are going to aluminum because they can buy a Chinese frame for $7 and sell it to you for $500.

I have consistently preferred bikes like the Lemond Zurich, as they are very well made and not quite as expensive as other Reynolds 853 bikes.  853 makes a very nice frame, and there are variations of quality amongst these frames.  At the top of the US built frames is the IF crown jewel.  I also like Columbus nivachrome, genius, and ELOS tubing, usually found on Italian
bikes, which cost a bit more than the Lemond, and often more than the IF. Torelli offers some very good values in Italian steel bikes, and you can't beat a Masterextralight for all around performance and looks, even though it costs more than most ti.



I have noticed a slight amount of give in my chain ring. If I hold the wheel with one hand and hold the chain ring with the other, my chain ring wiggles about very slightly. Is this common, and as a complete novice is it something I can fix myself or should I take it to the bike shop to have professionally repaired?

Thanks in advance for your help.



I would imagine with an email address like danskebank we should expect certain semantic problems with English.  The chainrings, or chainwheels, or even sprockets, are on the front part of the drive train, attached to the crank arms. I think that you are talking about the cassette, or cogs, or cluster, and if that wiggles a little, it's probably ok.  The more you spend on a hub, the less wiggle or free play you will have.  A $300 hub has practically no wiggle at all. There is not much that you can do about it unless it is due to a loose axle or freehub fixing bolt.



I just got a Specialized Hardrock with a Jett fork on it and I was wondering if I should clean it out at the end of the season. I've tried to find info on taking the thing apart but to no luck. Thanks.

Pete Groff


You can get technical manuals on rockshox website.  You need to find a long (300mm) 6mm allen wrench to remove the lower legs, and you'll need to get some shock oil, probably 5 or 10 weight.


Dear Andy,

A 3-piece crank. I would like to know how to tighten it.



3-piece cranks are held on with either a 14mm bolt or an 8mm allen bolt.  If you rode the bike for any amount of time with a loose crank, you probably won't be able to tighten it as it is rounded out and the arm will have to be replaced.



I have a Gary Fisher Mountain Bike.  It's a Mamba and a '98.  If you would be able to accurately gauge its value I could send you specifics about it, but if not I was just inquiring as to whether you know of anywhere besides a local bike shop that could judge it's value.

Thanks alot,


If the bike was perfect, it'd be worth about $250 to trade, or $300 to resale.  If it's not perfect, then it's not worth much.



I have a Schwinn Moab with a Cromoly frame and I would like to upgrade the front fork.  It is 1-1/8" threadless. My question is can I slide the old one out and slide the new one in there without replacing or rebuilding the headset. Are special tools required?



It's not quite as simple as you think, and you'll need a few tools.  I  recommend the following:  Park saw guide, star nut setter, and a crown race setter.  About $50 in tools for a $40 shop procedure. You won't need to do anything with the headset, other than remove the
crown race from your old fork and install it onto your new fork, or you can have your local bike shop install a compatible crown race onto your new fork. People do beat star nuts into the steerer with whatever primitive methods they can contrive, and you can get a "wedgehead" or "connix" type star nut replacement, which can be installed without the setter.


I recently purchased a used road bike with a Sigma Sport BC 800 computer. Do you know what numbers are needed to recalibrate the computer? 



You can call Sigma sport at 1-888-744-6277.


I just purchased a rear cassette through the mail. I was told it is Dura-Ace.  How can I be sure with only the model number to go on? The model number is CS-HG90-8.  



HG90 is the Shimano designation for Ultegra.  It is possible that there are no 8-speed Dura Ace cassettes in existence; however, if memory serves, old Dura Ace stuff only works well with other old Dura Ace stuff.  If you have a Dura Ace drive train, your cassette must be Dura Ace to work well.  If you don't have a Dura Ace drive train, then you shouldn't use a Dura Ace cassette or anything else.  If you need a Dura Ace 8-speed cassette, they are still on the books, but I would assume that they are scarce.  I could be wrong about the compatibility
issue, but if I am correct, even an 8-speed Dura Ace derailleur acts up in the presence of lower bred components. Shimano used to use numbers like HG90 for all component groups and refer to the king only by "Dura Ace".  Now, Dura Ace is designated by the 7700 number.

Hi Andy,

I borrowed a Cannondale Super V 4000 DH bike that is probably four or five years old.  It has Sachs disc brakes that don't work at all, especially the rear. Is there anything that you can suggest I try to get them to work?  I love the bike for downhill otherwise. 



I know people with Coda (Cannondale) disc brakes that are only four or five days old and don't work at all, so what are you complaining about? Most companies gave up on discs in the mid 90's, so it's not likely that you are going to get any replacement parts.  SRAM, the
company formerly known as Sachs, has excellent customer support. You can call them at 312-664-8800, and at least find out how to bleed the system. It should work if the shoes are not worn out and the system is bled. If you have any air in the system, it'll be real mushy, or in extreme cases, the brake will not even slow down the wheel.  Most hydraulic systems should be bled at least once every couple of years. 



I'm looking for a blown up diagram of the Sachs SRAM internally geared hub, the 3 X 7 model.



Check the SRAM website at www.sram.com, or call them at 312-664-8800.



My derailleur is out of adjustment. My chain keeps hitting the front derailleur cage when I shift to smallest front sprocket (with smallest rear sprocket). The chain also keeps hitting the cage when I shift to the middle front sprocket (with largest rear sprocket). I keep adjust it but nothing changes.

Think you can help me out?


Please look at old Ask the Mechanic columns. Derailleur adjustment has been covered before.



I have recently bought a Trek 6700 with Judy C. When I adjusted the preload,  I went too far. When trying to stiffen it, it feels like the knob has come loose and doesn't adjust any more. Please help me. Thank you.



If you cannot find adjusting knobs locally, I can get them for you.  I have a few in stock, but I need to know exactly what year your fork is.  These typically run between $12 and $20. If you have to crank the knobs this far, consider a heavier set of springs.



I have Shimano LX shifter/brake combo on my bike and would like to trade them out for shifter pods separate from the brake levers. How do I remove the cables from the shifter portion? There are a few small screws on the bottom side of the shifter part, but I don't want to screw anything up. The brakes I can handle, but I don't have experience with Rapid-fire shifters.

Thank You,


On some of these rapid fire pods, you do have to remove the cable cover.  There are two or three very small screws that hold it on. This is a big pain, and should be used to shut up anyone who complains about cable changes on grip shifters.



Recently, I purchased an old '74 Masi w/ Nuovo Record hubs. The hubs are really dirty and tarnished. What is the best method to clean hubs back to their original brilliance?  I need something besides blood, sweat, and tears.



You can really make these things glow, if you have the time and/or skill to separate the hubs from the rest of the wheel. You should probably consider replacing the spokes on a bike this old anyway.

Once the hubs are alone, it's fairly easy to polish them.  If they are really grungy, you can clean them first with a degreaser, followed by fine steel wool, and finished off with aluminum polish (mother's or similar).  It is almost impossible to do this with the wheel assembled.



Can you tell me in which direction I would unscrew the rear gear cluster (I have the correct Shimano socket). You advice and any tips would be appreciated. Thanks.



Freewheels unscrew counterclockwise, as do cassette lockrings. You must have a cassette lockring tool and a chain whip to remove a cassette.



I have a Cannondale F500 with a Headshok fork and would like to change it to use a standard 1-1/8" steering tube rigid fork.  I have a fork that is suspension-corrected and need to know if there is a headset conversion available for this.  I saw such a setup a year ago on an Internet auction but haven't been able since to find anything about it by searching the 'Net. The Cannondale web site doesn't say boo about this. Can you give me any direction? Any help will be greatly appreciated.



Cannondale headset reducers are widely available.  If you can't find one locally, I can get one for you in about two weeks.



I'm glad I found your site... Here's my question:

I thought the pedal had  come off, but when I looked down I saw half the crank still stuck to the  pedal!  The bike is a Marin Palisaides Trail and the crank  manufacturer is "Ovatation", or at least that's what's printed on the crank...the bike was purchased about six months ago, and gets almost daily use. It looks to me like the whole sprocket may need to be replaced, but I may be mistaken...   



Sounds like your crank arm came off.  Sometimes you can replace it, making sure that the bolt is very tight--you should check both bolts. If the arm is damaged, you can replace it for about $40.



I have some 747 clipless pedals on my mountain bike and I am gonna overhaul. Before you can take the bearings out you must take off a screw that puts tension on. How many turns should I make and what should I do about it?



The tension mechanism, and the entire body of the pedal, for that matter, are completely separate from the bearing/spindle mechanism. You should not take anything off the pedal body; rather, you should remove the pedal from the crank arm, and take the body off with the plastic pedal tool provided with the pedal.  From there, it is relatively simple to service both inboard and outboard bearings.  The biggest caution is that you don't loose any of the very small outboard bearings, as these can be hard to find, both on the floor and in the bike shops.  If you are having problems with the tension mechanism, that is probably best dealt with by a competent mechanic.



I am looking at two road bikes and seem to be stuck on which to purchase:

A LeMond Tourmalet with Shimano RSX components or a Marin Verona with Shimano 105 Components. Is there a big difference between these bikes and which do you think would be the better choice?  

Bill L.
Eureka, CA


Although I sell Lemond and not Marin, I'd be inclined to go for the Marin.  I think it's Italian, made of Columbus Thron, which is not quite as nice as the 853 frame in terms of strength or weight, but a fairly close second or third. The components are much nicer on the Marin, and I don't think either bike gets a carbon fork. If possible, test ride both bikes. The fit and feel of the Lemond could make enough of a difference to warrant consideration, but on paper, I like the Marin.



I'm tall, 80" with a 37" inseam. What size frame should I buy for a road bike?



While it is impossible to do a precise fitting over the internet, I can give you a reasonable estimate. The final determination should be made by visiting an experienced road bike oriented shop. If you actually have a 37" inseam, you're gonna need a big bike. I would guess a 63-64" in most brands, and possibly larger, but anything larger than 64 is going to border on custom built, and you are not likely to find anything that large for a fitting or test ride.



I have a problem with the freewheel on my bike.  It needs to be repaired (it spins both ways, and does not lock out).  Every bike store I go to says it's cheaper to purchase a new one. My dilemma is that I have an old Suntour (I think) rear wheel that has a "spiral" type hub and can only use freewheels with this spiral type of configuration. You have to push the freewheel
on to the hub then lock it in place with a threaded O-ring. (I hope you know what I'm talking about). I haven't seen any bike shops in my area that sell the type of freewheel that can fit my hub. 

Any suggestions on what I should do to repair my freewheel? Or should I get another one?  I've been to four different bike shops and they say they haven't seen anything like it and that maybe I should spend $100 or so on a new wheelset. My bike is an old Nishiki and, although I'm happy with it, I don't want to spend a lot of money upgrading it. I mean it's over 15 years old; would that $100 be better spent toward a towards a new bike? However, I like riding my "vintage" bike.  In fact I like keeping up with these guys with the $2000 racing bikes with my
vintage racer. Anyway, any help would be greatly appreciated.

Clete Vito,
bike enthusiast


I'm not sure, but it sounds like you have one of those Rigida Heliomatic hubs, which will only accept the cogset made for it, and parts for this hub would be nearly impossible to find. If that's the case, you do need a new wheel. If you have a traditional threaded-on freewheel, SRAM has several configurations available. Good quality threaded hubs are hard to
find, but available. I don't think you'll ever be able to repair a Heliomatic hub.


Hi Andy,

Thanks for reading this.

I picked up a Mongoose Iboc Zero G SX frame NOS for a comparatively low price which, of course, was necessary considering that I spent nearly all my hard-to-come-by-broke-college-student cash on components (mostly XT). I'm not sure of the year but it has a 68mm bb shell, it's chromoly and almost scarily light (honestly I'm used to a much heavier frame, is it safe for chromoly to weigh a little under four pounds?), a blue powder coat finish, and a very oddly-shaped drop tube profile. I was wondering if you knew anything about the frame. I've read all the reviews which ranged from "I cracked this frame in one day" to "I've been riding this frame for three years and I love it." So I don't really know what to think. The frame is still bare so I would really love an expert opinion on the quality of this frame before I make a big, huge old mistake and build up a frame that will break and kill me when I hop a curb in traffic.

Al Klek


What you have is a "true" Mongoose, frequently confused with the "false", or Walmart variety. This variety of goose was (is or shall be?) produced by as fine (or cheap) a factory as could be found on the isle of Taiwan. I seriously doubt that your "International Bicycle of Champions" weighs less than four pounds, but it is of significantly better quality than
the current deluge of $7 Chinese slave-labor-made aluminum frames that everybody loves.  Cromo is more than light, it is durable and repairable. I once straightened a true temper frame that had been run over by a car, and other than cosmetics, it has been fine for the last five years. While it is certainly not my choice of frames, you could do a lot worse. In bike years, this thing is ancient, at least 7 or 8 years old,  so I'd look hard for internal rust, maybe buy a can of frame saver.


Hi Bikexchange,

Great site. I enjoy visiting regularly.

Suggest your expert mechanic let viewers know about Campy vs. Shimano bottom bracket incompatibilities. From recent dealings, its become obvious few are aware of the taper differences. People, including some pro mechanics, are ruining good (expensive) cranksets because they're unaware of this.  Branford Bikes has an item on it //www.branfordbike.com/bottombr/bb1.html

Ford Kanzler
El Granada, CA


I think I have alluded to this situation at least once or twice. We in the know are always advising people on such issues, and usually this advice is ignored when a low price enters into the picture.



I have an early 80's Bianchi that had a 5-cog freewheel on Campy hubs. My wheels were stolen and a friend gave me a set of wheels with Shimano 105 hubs and a 7-cog cassette. Will this work with my Campy derailleur and 2-ring cranks, or am I asking for trouble?



You will probably find that your derailleur won't quite lift the chain onto the lowest one or two cogs. Since you have a friction system, the simplest solution is to replace the der with almost any 7/8/9/10 speed der available. If you are a purist, take the cassette apart and figure out which two cogs you can live without--some replacement cogs are available if you want to even out the gaps--and take up the space of the missing cogs with spacers on the inside of the cassette.  This way, you can keep your vintage der and utilize cassette technology.







As far as I know, Tirelife is still available.  I don't have it in stock, but I should be able to get some to you some in about 10 days. Your cost with shipping is $9 per 4 oz bottle. Either send a check for the amount you need to Wheelcraft, Ltd, 2100 National Rd. Wheeling, WV 26003, or call 1-888-547-0202 with credit card info.



My name is Jon and I just had a question about an arm and leg powered bicycle.  Is it possible and if it is how would you go about setting one up? Any additional information on this kind of bike would be helpful. Thank you very much.


The only alternative to leg powered bike that I'm familiar with is the Freedom Rider.  It is a 3-wheel hand powered beast and I believe the entry level bike is in the $1300 ball park.  They are available direct from Freedom Rider. That's really all I know about that.



My name's Michelle and I'm doing a paper for school on Gears and Changing Speeds. Could you tell me a little about this subject? It would be a great help!



You can email back for more detailed information if necessary, but here is an overview.

The standard mountain bike has three chainrings (also called chainwheels or sprockets) in the front and 8 or 9 cogs in the back. Road bikes usually have two chainrings and 8, 9, or 10 cogs, but some of them have 3 chainrings. Simply stated, you have what we call "big" gears and "little" gears. Big gears go fast, and little gears climb hills. On a standard road bike with 2 chainrings and 9 cogs, your biggest gear happens when you put the chain on the biggest chainring and the smallest cog. This gear is best referred to by the number of teeth on the chainring followed by the number of teeth on the cog, or 53/12. This is the fastest gear on the bike, because a single revolution of the chainring produces several (I'm not going into the physics of the thing here--to be exact, you'd need to count wheel rollouts, or perhaps your physics teacher could devise a formula for exactly how many) revolutions of the rear wheel. Conversely, the little gear happens when the chain is on the smallest chainring and biggest cog (usually 39/23 on road bikes), and this is the easiest gear to climb hills with, because a single revolution of the chainring produces something close to a single revolution of the rear wheel.

If you had a bike with only 3 chainrings (20-30-40) and 3 cogs (10-20-30), and no wheel size involved, you cold devise gear ratios, like 20/20=1:1; 20/30=2:3, etc. Bicycle people have devised a system for comparing gears called gear inches. To determine gear inches, you multiply the tire size in inches x the number of chainring teeth and divide by the number of cog teeth. While it is erroneous to use this number as a representation of a physical event, it is useful in that you can use the gear inch number, like 52 or 26 to compare gear changes on different sized wheels, or to better understand the difference in changing cog or chainring sizes.

Hope this helps,

Hi Andy,

I just recently started to ride road bikes and have a question about adjusting the height of the headset. I understand that a device may be available that would allow the headset to be elevated higher than is safely possible. I need to raise it at least another 1/2" to 3/4" to relieve some stress across the shoulders. The bike I have is a Raleigh and has the normal threadless headset. Any help you can give would be appreciated.

Leon Black


The only thing you can do (other than buy a new fork and cut it to the desired height) is to try and find a stem with more of a rise than the one you have. Since road bikes tend to be set up low in the front, most stems that clamp road bars are of the 90 to 73-degree type. A quick survey of available options indicates than 105 degrees is the max.  If that does not provide enough height, the only other option would be the Zoom Heads Up Extender, which I believe only comes in 1-1/8". This thing will get you real tall, and is very comfortable. In fact, it works great as long as you don't have to steer. It's also really, really, ridiculously tall. If you don't already have a 105-degree stem, that's probably the best you can do without problems or a new fork.



I don't have a mechanical question but perhaps you can help me nonetheless. I'm 6'8" tall. Where can I find apparel like outer shells in so called, long or tall sizes?

Thank you in advance,


Contact Lennard Zinn of Velonews fame. I'm more familiar with his frames and technical expertise, but he also is a big guy and has a sort of big and tall clothing business.



I have a Backtrail X1 and when I ride it the crank makes a grinding noise. After I got new bearings, I brought it into my local shop and they couldn't find what was wrong with it. I hope you might know what the sound is. Please write back. Thanks.



It could be a lot of things. If the bearings are good and properly adjusted, then I'd make sure that the chain is not too tight, or look at the chainring to make sure it's not bent.


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