Ask The Mechanic

Here are old Ask The Mechanic questions, enjoy

 

Spring/Summer 1997                    Autumn 96 ATM | Winter 97 ATM

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.

Read the Ask the Mechanic Disclaimer.

Spring/Summer 1997 Questions…

Dear Andy,

I am a low-budget biker. I purchased an old Nishiki from a friend for $10, put on new tires and water bottle. I added a new crank and bottom bracket and grabbed the derailers from a newer old Nishiki.

The frame I’m using now is big. I’m not sure I measured from the right spot exactly, but it is 61 by 61 cm. The newer old Nishiki is 56 by 51 cm. I’m six foot tall.

So what’s the questions? Would I be better off throwing everything onto the smaller frame with an extended neck on the handle bars and with the seat moved back as far as possible or stay with what I’ve got?

The idea is keep it within my budget (cheap!) What do you think?

Martin Malley

Martin,

Your question is impossible to answer. However one measures frame size is irrelevant–an old 60cm may have a 30″ standover height and a short top tube, where a new 58 may have the same standover with a long top tube. These dimensions vary from year to year and vary widely among manufacturers. A person who is 6 feet tall could have 3 feet of leg and 3 feet of torso, or an almost infinite number of combinations. If you are comfortable on the 61 and have enough clearance over the top tube, then that’s probably your best bet.

Andy

Dear Andy,

I  own a 1994 Bridgestone MB-2. It still has the original Deore LX 7-speed shifters on it, although it has many wonderful upgrades (i.e. Cooks Brothers Crnks, XT V-brakes, etc..) I would like to put a set of XT rapidfire shifters on it. What is the least expensive, and most effective way to make the switch from 7-speed to 8-speed; or is it possible to use 8-speed shifters on a 7-speed cassette by blocking out the 8th speed? I could use your help as quickly as possible. Thank you very much!

Ryan

Ryan,

The 8-speed shifters will work with 7 cogs, so that would be the cheapest way to go. If you wanted to convert to 8-speed, you’d need to buy an 8 speed freehub body and cassette, and possibly some assorted axle hardware. We convert 7 to 8 speed wheels here for about $70.

Andy

Dear Andy,

Read with interest your Interbike Page. I am considering getting a 7-speed internally geared hub but don’t know whether to go with the Shimano Nexus, the Sachs or the Sturmey Archer (very new, I understand). My heart wants the Sturmey (I ride one to work everyday) but I’ve heard that Sturmey’s quality has gone downhill of late. I’d appreciate any comments or experience you’ve had with these. Thanks.

Francis in Philadelphia

Dear Francis,

As much as I hate to recommend that you or anyone else patronize a monopolistic, tyrannical foriegn power whose distribution and pricing policies border on illegal, buy the Nexus. I would strongly suspect you’re right about the Sturmey, and I’ve had a heck of a time finding parts for Sturmey Archer recently. I believe that Pearsons Majestic Saddles is the sole US distributer, and their inventory consists of 2 triggers and a cable. The Sachs hubs are outstanding, but I would get the Shimano, because it is extremely reliable, easy to adjust and maintain, and you should be able to get parts for it for at least 3 years. We have sold a few Gary Fisher Alfrescos with Nexus 7, and I was very impressed with the smoothness, ease of shifting, gear range, and the Nexus brake. The only improvement to this bike would be to add the Nexus front hub, but that would hike the price quite a bit.

Andy

To all you folks with questions pertaining to off-beat bikes:

In the last 10 years, about 100 new brands of bicycles have come and gone. This is primarily due to the mountain bike craze and the ease of having your own special brand built to order in some oriental place (preferably not China). Since the 1890’s, when Schwinn, Fuji, and Miyata were new companies, how many thousands of companies have come and gone? If you have a 1975 Lambert, I can probably fix it (I once had one), but I can’t tell you much about it. So, as much as I’d like to help you folks find out about your Kettlers, Gitanes, Grandis’s, genuine Schwinns, and Dinglehoffers, I’m a mechanic, not a curator. Also, I plain old get hostile about anything with an internal combustion engine (except for an occasional Wizzer in pristine condition).

Andy

Dear Andy,

How would I go about disassembling a set of 1993 Shimano Ultegra STI lever to clean them?

David Faller

Dear David,

I would only disassemble these levers if I was experiencing a problem–you can do a fairly good clean and lube with Finish Line Eco-tech degreaser and a good light spray oil. If you must, you can peel off the name plate on the front of the lever, remove the small stopper screw revealed when you push the lever toward the center of the bike and remove the fixing bolt (usually an 8mm bolt–use an 8mm socket). Some older STI levers require a few special “tools” to get to or beyond this point–I’m not sure whether yours falls into this category or not. Assuming that standard tools will get you to this point, the plastic lever cap, spring and dust seal will pull off. Shimano suggests swishing the lever in kerosene and allowing it to dry. I guess that this accomplishes both cleaning and lubing; however, I’d rather use something a little more environmentally friendly and less toxic (Eco-tech). Do not attempt to dissassemble the lever any further. I know this sounds a bit vague, but essentially you just remove the lever, clean it, lube it and bolt it back on.

Andy

Dear Andy,

I have a Giant Kronos road bike that has a sealed cartridge bottom bracket. I have around 1500 miles on the bike. When will this bottom bracket need replaced? Thanks.

Bill C.

Dear Bill,

Most likely, your bike has a Shimano un-72 or cheaper bottom bracket. These things can last anywhere from 20 minutes to 5 years. As a rule, it’s cheap and easy to replace them every 2000 miles (more frequently if you get your bike wet a lot), or upgrade to a serviceable bb such as American Classic and probably never replace it if it is properly maintained. Maintenance for the Shimano units involves throwing them away and replacing them.

Andy

Dear Andy,

I forgot to ask this question the last time I e-mailed you. I have a 1995 Giant Kronos with EXT-TEC hubs and one of my front cones is starting to pit. The nearest bike shop is 75 miles from my home. Is there a way that I could get this and other small parts through the mail or do I have to take the cone in and show it to the mechanic at a bike shop?

Bill C.

Dear Bill,

Small parts such as axle cones or even axle sets are not generally available through mail order. Most shops do not stock a lot of them, especially exotic (non-Shimano) cones. If you can provide me with very specific information on these hubs, I may be able to find you a pair of cones. I’ll see if I have any info on these hubs and if there is a compatible Shimano cone, but I’m really not familiar with this brand.

Andy

Dear Andy,

I have a friend’s wheel apart on the floor here. We have a Suntour Power Flo 7-speed cassette that is ridden hard on a mountain bike. We diagnosed the symptoms of an excessively slipping cluster to the “Body,” that small cylinder that contains the pawls and springs. The lockring that retains these parts is on pretty doggone good.

My question is-and I have a follow up, please-

What direction are these threads? I’m not sure if they are the good old familiar “lefty-loosey, righty tighty” right-handed ones or if they are that elusive left-handed thread reserved for left pedals on one-piece cranks like on my mom’s tank bike, right-side fixed cups and some 80’s Chrysler car lugnuts if my Chilton’s memory serve me correctly. After you tell which it is and I pop it open to find the pawls and springs worn but the body ratchet O.K., will you folks have any of those now ever more rare Suntour small parts available for purchase? Are there any other left-handed threads lurking out there on a bicycle that I should know of before I bust a knuckle or strip something that I assumed was a frozen right-hand thread? (BTW, I work on the Space Shuttle for a living and have yet to encounter a left-handed thread on it).

John Kazeva in DC. Editor note: Check out John’s website, Bicycling In the DC Area

Dear John,

Are we talking about a freewheel or a cassette here? Neither one is easily serviced and I wouldn’t take the body apart unless you really enjoy tedious, time consuming, aggravating activities. It sounds as if you are describing a freewheel, and the lockring is indeed left hand threaded, and is probably on quite tight (the race on cassette bodies are also left hand threaded and difficult to remove). Suntour parts are difficult to come by. However, if I’m not mistaken, the Powerflow 7 cassettes of 1993-94 were Shimano compatible, so it stands to reason that Shimano freewheels or cassettes of the same vintage should be Suntour compatible.

At any rate, if you want to keep the Suntour drivetrain (because of its incredible precision, no doubt) try slapping on any old freewheel or cassette. Most of the time, the performance is not perceptibly worsened. In fact, I have a cannonade racing bike with a Suntour Sprint drivetrain, and it actually works better with a Sachs freewheel than with a Suntour. Buy a Falcon freewheel for $15, or bolt on a Shimano system for about $50, because you won’t find freewheel parts anywhere. Normally, the fixed cup of your English threaded bottom bracket is left hand threaded, as is the left pedal. I think it’s one of those French things, like presta valves, that doesn’t really have an explanation or function, but won’t change anytime soon.

Andy

Dear Andy,

I am new to cycling and am having trouble adjusting my rear derailleur. It is a Shimano Acera-X and no matter what I do it does not seem to want to stay in gear 1. Any help you could give me on the adjustment process would be greatly appreciated.

Michael at the University of Florida College of Law

Dear Michael,

You cannot get into first gear for one or more of the following reasons:

1) Your low limit screw is turned too far in. This screw is marked by a barely visible “L” on the back of the derailleur. If you cannot force the derailleur in first gear by pushing it with your hand while turning the crank, turn this screw counter clockwise until you can.

2) Shift cable is too slack. This would have other symptoms, like not being able to shift off the 7th cog. Either tighten the cable with adjusting barrels or by loosening the anchor bolt and pulling the cable tight.

3) Your der. hanger is bent. This should be checked by a competent mechanic and would be indicated when 1 and 2 fail.

Andy

Hello,

My girlfriend bought a 1995 TREK 850 and, a few months after she got it, the headset became stripped. (She never did anything but on-road riding.) Since then, she has purchased another bike but what should we do with the other one? Will TREK fix it if we ask nicely? The dealer was less than receptive to our needs…

Thanks,
Randy in Columbus

Dear Randy,

This is a rather sticky situation, and my opinion may not be very helpful. Trek probably would not fix it unless it has been determined that they used a defective part (possible but not likely). The manufacturer’s warranty usually only covers the frame and mechanical parts, and it seems to me that you either have an assembly problem or an abuse/neglect situation. While you say that your girlfriend did not abuse the bike, how long did she ride with a loose head set? If I made a decision in a similar situation and the bike did not come back in for a 30 day check up, then you would have to pay for the repair. Good mechanics should check head sets in the assembly process; however, especially with threaded head sets, there is no guarantee that it won’t loosen up the first few rides, especially if it was just casually checked during assembly.

On the bright side, you could only have a stripped locknut, which would only cost a few bucks, and if the entire headset (hopefully not the fork) needs to be replaced, one of equivalent quality should run less than $40 installed.

Andy

Dear Andy,

You wrote the most impressive bike trade show report I have ever seen(see Andy’s Interbike Feature). So, well, meaningful. I’m a long-time roadie (since 1969) who, when I want to see the natural world, prefer to walk rather than ride. Maybe I’m just chicken to take a header (having never fallen on my bike as an adult save for twice with my wife on a tandem). I have a 1993 Campy Record grouppo using a Campy OR triple crank (they came out with the road triple the next year, and Bicycling Mag started “discovering” what so many bike tourists have known for decades). I use a regular Record rear derailleur, and it works fine. I really like the setup, and find that I stand on the bike a lot more when I can shift. All of that is give you a brief profile of me as a non-techno-phobe but not-quite-techno-weenie. So I was real skeptical of Campy and Shimano’s new 9 speed groups, and Bicycling’s eagerness to embrace it. There’s a nice argument against it in that blatant pro-Campy web page, can’t remember the address right now. I’ve read all of the Rivendall’s website, and find their arguments interesting but not compelling. I really like the old bikes, but I think some of the newer developments are improvements if you can afford them (I can, to some extent). Your review was short on hype and long (but not long-winded) on what was useful at the show. I don’t see that kind of review elsewhere. So please take my comments on your writing as high praise. Keep it up!

A question:

I weigh 190 lbs., am 6’2″ (a little overweight, but it IS that time of year), and broke a couple of spokes in my Schwab-built Record wheels with 32 DT 14 straight gauge spokes and Sun aero sewup rims. So I tightened all the spokes maybe ¼ turn. A year later, I discovered that the spokes pulled through the rim (no grommets). The rims stayed true, otherwise.

So I need to buy some new rims. I have built two wheels in my life, and don’t want to take the time to build them myself and possibly screw it up. I do most any other kind of bike repair and maintenance, though, and enjoy it. What would you recommend? I’m leaning toward Campy rims, because they’re relatively cheap, come with grommets, and are otherwise relatively light. Mavic’s GP4 is probably fine but it seems heavy. I don’t race, but I do like to accelerate a lot, so I’d prefer something light yet sturdy. Mavic also has new this year a sewup version of their Reflex, which is very light (375g) and hopefully strong. Would that be a good rim? Jobst Brandt says that 14-15-14 gauge spokes make a stronger wheel than straight gauge because the compression loading is absorbed more by the thinner inner gauge, so that the whole head doesn’t move around in the hub as much as the straight spoke’s head would. If that is true, would the new DT 14-17-14 spokes be better yet?

I’m sure you would have to be more careful with windup when tightening the spokes during building. Can you, at your shop, take my hubs and build me a pair of wheels with these components? How much would you charge (for what rims and spokes). Please let me know.

Thanks for taking the time to read this, and keep up your good work. I hope your business thrives. I like what I know about your business style, too.

Thank You,
Mitch Hull, Rheologist, A.E. Staley Mfg. Co., Decatur, IL 

Dear Mitch,

I appreciate your appreciation and I’ll help you out if I can. It is a CRIME that Mavic no longer makes a nice light tubular rim like the GL280 or GL330. All of this aerodynamic stuff going on makes it tough on the guy who just likes to climb hills or ride on a comfortable wheel. What’s really sad is that most high zoot tubular rims are geared to triathletes, with deep v sections, not much resiliency, and extortionate price tags. When you ride a real stiff bike in a place with chewed up roads (like here in Northern WV), there is nothing like a good (even cheap) tubular tire to take the edge off.

My suggestion is to get a rim with eyelets, with a shallow v section for strength, and use the thin butted spokes. I don’t have much experience with the DT spokes you mentioned, but have logged many a brutal mile on Wheelsmith XL-15’s on my mountain bike. I’ve only broken one spoke it 2 years, and that was due to a large stick through the wheel. These skinny butted spokes have to be carefully tensioned, and when they are re-trued, allowances for windup have to be considered. Since Mavic is really not doing much with light weight tubulars right now, I would consider the Campy Seol 88 rim. It’s fairly light (about 420 g, I believe) and has grommets and a shallow v section.

Should be had for less than $60 each, and should be pretty tough, especially since you’ll be using spokes that are about 6mm shorter than with a traditional box section rim. I usually charge less than $25 per wheel to build, using proper lubrication at the hub and rim, and Wheelsmith spoke prep. The spokes I suggest would cost about $.65 each with brass nipples. The only problem with shipping wheels is that even if they leave here 100% perfect and are professionally packed, by the time they have gone through UPS or other handling, they need to be trued again (if you’re lucky, that’s all they’ll need). Call me (1-304-547-0202) and we can discuss other options.

Andy

Dear Andy,

Do you know where I can find Benotto Handle Bar tape? It used to be real
popular but must have taken a big back seat to padded tape. Anyway, if
you’re mounting bar end shifters in a clip-on or cowhorn bar and you want
to end the tape inside the bar (held in place by the shifter) only thin
tape like Benotto will work. Easy to work with and looks great too. Any
ideas? Thanks.

Rick

Dear Rick,

I thought that Bennotto (or however it’s spelled) died a well deserved death in about 1983 or so; however, according to Bikealog, it’s available through at least two distributors in the US, presumably still in its slippery, unpadded original state. Contact your local shop, and if you don’t have any luck there, check with me. The Bennotto tape is still a bargain at about $5.00 a roll.

Andy

Winter 1997                                  Autumn 96 Ask the Mechanic

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.

Read the Ask the Mechanic Disclaimer.

Winter 1997 Questions...

Dear Andy,

When greasing my rear hub, how tight should I tighten the wheel? I found that if I tighten it too much the wheel won’t spin well and if it’s too loose it falls apart. I can’t seem to find a happy medium. Also–any tips to improve my shifting on my SRT-400s? It works great with a new cable but rapidly deteriorates.

Joe

Dear Joe,

When adjusting rear hubs, it is important to have the drive side locknut tight against the spacer or cone before trying to adjust it. Assuming that your internal hub parts are in good shape, once the drive side is locked down, snug the cone down on the left side, then run the locknut on finger tight. Check for excessive play or binding and correct this before finally locking the locknut to the cone. I usually prefer to have a very small amount of play, as the quick release skewer will compress the bearings slightly when closed. If the wheel does not spin well with only a slight amount of play in the axle, either the cone, bearings, hub races, axle, or all of the above need to be replaced.

Sometimes, the dust cap in the freehub gets out of alignment or deformed (if you removed it, it is probably deformed) and causes drag, and sometimes the rubber dust cones bind and cause problems. There are many things one can do to make grip shift work well. Eliminate any friction and dirt, properly lube the system, and it should perform very well. Always use a “slick” or die drawn cable. Make sure you are using sis type cable housing, and a lubricant that does not bloat the nylon liner (Finish Line Professional or Gripshift Johnnysnot). Stretch the cable several times by holding the shifter in 1st gear while pulling on the exposed cable. Stretch and reset the cable tension using the adjusting barrels and after about 5 stretches, reset the tension with the barrels screwed almost all the way in.

There are many fine aftermarket products which improve grip shift. The most effective and easiest to install is a grip shift Bassworm. Teflon coated cables such as Slickwhips or Gore are well worth the investment and, if you are patient, mechanically-inclined, and don’t mind a little bloodshed, the high tension derailleur springs (power spring, crumpet spring) really help out. I have also seen good results with the cable pulleys like the Avid Rollamajig.

Dear Andy,

Would you have any advice for someone having rusty chain problems every day? Being in the wet, cold and salt makes it rust up nightly. Should I worry or just keep oiling everyday with Phil’s Tenacious Oil? Thanks for the help.

Shirley Nate

Dear Shirley,

Phil’s tenacious oil is probably ok for chain lubrication; however, if you are riding in a lot of slime, mud, crud, salt, etc., a heavier brew might work better. Try Finish Line’s Cross Country Lube, or a similar heavy synthetic. This type of oil lasts longer, especially in sloppy, wet conditions. If you’ve tried thick oil and still get regular rust (possibly due to coastal conditions), you can use grease. I don’t recommend it, but some folks use grease on their chains in the winter and early spring (mud season) because it doesn’t come off every time you ride across the lakes that form in the middle of what used to be the trail. It makes a gooey mess, but it keeps the rust away.

Dear Andy,

I recently had my bike seat and post stolen in Philadelphia (not unusual) and I’m trying to find out what size seat post I’ll need to replace the stolen one. The bike is a 1993 Fuji Thrill. Is there any place I can find out this info short of bringing my bike to a shop? Thanks.

Mike Malone in Philadelphia

Dear Mike,

Most likely, your 1993 Fuji Thrill uses a 26.6 seatpost, although I can’t be totally sure. The best thing to do is to take the bike to a shop where the seat tube can be measured and get your post there, or buy a 26.6 and, if it’s too big, exchange it for a 26.4. I’m sure it’s one or the other. You know, bike shops aren’t such bad places to visit. I mean, going to a bike shop is nothing like going to a dentist or a funeral, so why not just take the bike to a shop and do it right. You should be able to purchase a better than stock post for under $25.

Dear Andy,

I own a Specialized air/oil Future Shock and have had the stanchion tube and the adjuster knob recently replaced on one side. My problem is that the adjuster knob no longer has any effect on the ride of the fork. The other side still works fine. What could be the problem and could I fix it myself?

Ryan Shields

Dear Ryan,

I suspect that whoever worked on your fork did something wrong–my experience has been that very few bicycle mechanics can adequately deal with air/oil shocks, beyond minor things like changing oil. Considering the level of service and the relatively low cost, it just makes sense to have this type of fork serviced by Rock Shox or BTI, rather than pay about the same to have someone of questionable ability hack away at it. I do a lot of suspension service, and usually I will send a problem like this to Rock Shox for fast, reliable service. You would probably pay well under $50 for this repair including shipping. It’s possible that you don’t have the same amount of air or the same oil height in both legs, and this is something pretty easy to check for yourself. Just check the air pressure in both legs with your suspension pump. If the air pressure is the same, you want to check the oil level. You’ll have to let out all your air and remove the aircaps. Measure the oil level in each leg with a thin ruler. If the oil height varies by even a small amount, this may account for your problem. If you check the air and oil levels and still have a problem, take it back to where the work was done and demand that they either fix it or refund your money. Next time, call Rock Shox.

Dear Andy,

What are the usual steps a mechanic takes to “winterize” a bike?

Ross in Scranton

Dear Ross,

I’m not sure if you want to winterize your bike for storage or for riding, so I’ll address both options. If you plan to store your bike during the cold months, there are only a few crucial concerns. The bike should be nicely cleaned and well lubricated (cables, chain, etc.)  I prefer hanging the bike by the rear wheel. It’s okay to hang it by the front wheel, although I suspect that this is not recommended if you have a front suspension.

Don’t store the bike near any solvents or sources of ozone or air pollution (near cars, gasoline lawnmowers, dryers, etc.) as this destroys rubber and harms plastic parts. If the bike is hung, then you don’t have to worry about tire inflation. If you cannot hang the bike, you must keep the tires inflated or they will probably be damaged. If you must store your bike near a clothes dryer, it should be covered with plastic or canvas to prevent lint, humidity or ozone from attacking. If you really love your bike, clean it up and make it part of your decor, like the Seinfeld Klein.

If you want to ride your bike all winter, cleanliness and lubrication are the keys. A thicker than usual chain lube–although it collects dirt–will hold up to the slop and mud better than the “dry” light lubes. Road chemicals should be cleaned off immediately, followed up with thorough lubrication. You are more likely to get flats in the winter due to cinders on the road, so a tire liner is a very good investment–try fixing a flat with gloves on or with nearly frostbitten fingers. Some extremists go for studding their tires or tire chains or cleats. This works well on snow and ice, but it’s horrible on pavement. A larger, more aggressive tire, such as the Continental Top Touring, is a good idea for road bikes. If you have a steel frame, you may consider a frame saver treatment. This will help prevent internal rust in all conditions.

Dear Andy,

Do you know of a company that makes 4-wheel bikes that carry two to four people?

Ken in Zachary, LA

Dear Ken,

Quadracycle (6715 E. 500 South St., Hamilton, IN 46742) is the only company that I have ever heard of that makes 4-wheel bikes. I’ve never seen them in a store, probably because of space limitations.

Dear Andy,

I’m looking for information on “Azonic” frames. Could you please help me locate information on them?

Brooke in Baraboo

Dear Brooke,

Try www.azonic.com

Dear Andy,

What do you think is the best lightweight tool kit available? Is it better to assemble your own for less?

Patti in Cincinnati

Dear Patti,

When it comes to small multi-tool kits, I tend to take a retro approach. Like many products aimed at cyclists, they tend to be the perfect solution to a problem that does not exist. I don’t mean to say that they are all useless–I’ve used a Ritchey CPR 14 with some success, and I like the features on some of the Topeak kits. However, how much roadside/trailside maintenance are you going to really do? Due to the small size of these kits, they can be difficult to use, and it is impossible to correctly torque certain bolts using these tools. Some of them have a crank bolt wrench. Cranks need to be torqued to about 300 inch pounds. Most humans need a bit of a lever to produce that much torque.

If you want something purple or blue that has a high coolness factor (but limited use) buy the CPR 14. I have ridden tens of thousands of miles on the road and in the woods with only a cheap chain tool, two tire levers, a patch kit, small screw driver, and a 3-way Allen wrench. That will usually cover it. I recommend finding our exactly what size nuts and bolts are on your bike, finding out just how hard said nuts and bolts are to tighten, and deciding if the purple anodized tools are going to work. You will carry more weight and possibly have some rattling in your tool bag, but the full-size, old fashioned tools work well and cost less. One of these days, I’d like to replace my Rivoli chain tool with one of those SRP Titanium jobs, but you know, losing a $6.00 tool because you forgot to zip the bag is frustrating; losing a $60.00 tool…

Dear Andy,

I have a 5200 Trek OCLV. I have had problems with the bottom bracket coming loose so that the crankset wobbles slightly. It is alright to use a liquid thread lock compound on the bottom thread?

Alan

Dear Alan,

If you are using a stock bottom bracket (probably a Shimano Un 71 sealed unit), the problem could be the bottom bracket and not loose cups. Even good Shimano bbs have a relatively high failure rate, as in they wobble. They say that Park tools has a magic voodoo stick for adjusting these bottom brackets, but Shimano calls these units non-adjustable sealed cartridges, so I treat them as such. Ride ’em for 200 or maybe 2000 miles and replace ’em–they’re disposable, not serviceable.

I would hesitate to recommend a thread locker in this case, especially if your bb cups are aluminum. “Cold welding,” or galvanic corrosion can occur when certain metals are in constant contact for long periods of time. When this happens, whatever metal was screwed into whatever other metal can never be unscrewed. This is especially common with titanium and aluminum (your OCLV frame has an aluminum insert in the bb shell). It is generally advised to use grease rather than thread lockers in most cases.

If you’ve ruled out the often faulty Shimano bb, or are using a cup and cone or adjustable bb, and the cups are properly torqued (400-500 in lbs.), and the thing continues to loosen, try some plumbers’ Teflon tape on the threads. This will help keep things tight, and it also prevents creaks and galvanic corrosion.

Andy

 

Autumn 1996
Ask the Mechanic Disclaimer

How can you keep your classic from becoming extinct? What’s the best way to lube your freewheel? Stuck in gear and need expert advice? Ask Andy the Mechanic (a.k.a. Andy Wallen), the proprietor of Wheelcraft Bicycles of Wheeling, West Virginia. We welcome your questions. The squeaky wheel gets the grease! Email to ibike@bikexchange.com, subject “ask the mechanic.” Andy will email you your answers and we may post them afterward.

 

Dear Andy,

A friend has a 700c wheel (Mavic rim, White Industries hub, and DT spokes) which was built by a local shop. The wheel keeps making a popping sound, but nothing happens. No broken spokes, etc. and the wheel remains in true (approx. 400 miles of use). This sound goes away after awhile but then returns. Any ideas on what’s causing the sound? Many thanks for your help.

Ron K.                                                                  (posted 9/28/96)

 

Dear Ron,

I suspect that your popping sound is happening in the hub–assuming that the spokes are all properly tensioned and intact. The White Industries hub is among the best, but it has some idiosyncracies. Without having it here to inspect, I would have to guess that either there is a bad bearing (this could happen even if the hub was brand new), or, most likely the preload is not adjusted properly. Another possibility is that the set screws on the adjustment collar are not secured, causing noise and friction as the screw rubs against the hub shell. If the sound is more pronounced while standing, especially if it is the front wheel, I would attribute it to slack spokes or possibly a loose eyelet in the rim. It’s possible that all you need is a little more grease in one of the bearings. Check all this stuff out, and if it still makes noise, either get yourself a $60 wheel or turn up the radio.

 

Dear Andy,

How much lubrication should I put on my road bike chain? One friend recommends just a thin coat of Teflon spray. My brother says I should have a fair amount of lithium grease on there. Which is better and why? Thanks.

Mike S. in State College, PA                                        (posted 9/28/96)

 

Dear Mike,

Never ever use any lithium grease on any part of any bicycle. It may be ok for seatposts or quill stems, but not for bearings, and certainly not for chains. To properly lube your chain (road or atb), first make sure it is clean. “Clean” is a relative term. At least wipe off the chain, derailleur pulley wheels, rear cogs, and chainrings with some degreaser (Finish Line, Citrus Solve, Joy, Windex, etc.) A good chain cleaning system is highly recommended, and in some cases, a total teardown is necessary. Once you are sure everything is relatively clean, apply a bicycle-specific lubricant (I can not say that Teflon, oil, or synthetic is preferred—it depends on the situation) to the chain by dripping it onto each link from the underside of the chain. Rotate the pedals backwards until each link has been lubed. Run the bike through the gears and let it set for a few hours. Then wipe off any excess lubricant from the side plates of the chain. This will help prevent gunk build up and help keep the drivetrain clean. The preferred lubricants in my shop are: 1) Triflow–works for everything, and it’s cheap; 2) Finish Line prolube (teflon)–very clean, effective lube, requires more frequent applications and good clean components to start with; 3) Finish Line Cross Country Lube (synthetic)–thick and gooey, attracts dirt, but lasts a long time, especially in wet conditions–nice bouquet; 4) Thin Grease (Finish Line, Nuke Proof, Park, etc. ) for hardcore, stupid, muddy mountain biking. Mud removes almost any other lubricant, so for really horrible mud grease is ok. Requires thorough cleaning and probably disassembly of entire drivetrain after use.

Dear Andy,

I want to get my first high quality, new bike. I’m getting a mountain bike. What steps should I take to get the proper “fit” from a dealer? Thank you.

Bridget D. in Columbus                                                      (posted 9/28/96)

Dear Bridget,

In sizing a bicycle, several factors should be considered. Above all, the size of your bicycle should be safe. The “standard” safety measurement is “standover height.” This is the measurement from the floor to the center of the top tube of the bicycle. For mountain bikes, especially if they are going to be ridden under gnarley circumstances, smaller is better. I recommend at least 2 inches over the top tube, while 4-6 inches might suit you if you are planning to ride technical stuff. Whatever your leg length may be, you also want to consider how the bike feels. Top tube lengths vary, so if you have a short upper body and longish legs, the so called NORBA geometry may not be for you. Most ATB enthusiasts like a long top tube (approx. 23″) with ample, safe standover height. My advice is to try at least 2 frame sizes and at least 2 different brands of bikes to find the best fit.

http://www.bikexchange.com/askmech.htm

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http://www.bikexchange.com/askmef96.htm

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