Tuesday, March 24, 2009

Q&A: Carbon touch-up, triple upgrade, how much chain lube

Q: Hi Jim, You can use the techniques described to remove bar logos too
I have a Bontrager X-Lite carbon handlebar that I want to sell, and I don’t know what I can use to polish it up. The bar’s scratched where the grips were, and I need to make it look shiny and pretty as much as I can! How would I go about that?

Thanks!
Staci

A: Good question, Staci. Since the handlebar is actually scratched, you're probably going to need to refresh the clear coat that was originally on there in the area that was scratched. (I'm not positive your bars had a clear coat, but most do.) An easy shortcut that might work is to just get some clear fingernail polish and take the brush and try painting the scratches just like you were doing your nails (if you do), and see if the scratches disappear. That sometimes works. It depends on the scratches but maybe you'll get lucky. If so you'll be done with your "repair" in a few minutes, plus drying time. This works as a way to touch up a paint chip on carbon frames or parts too. Just get the right color of fingernail polish for a paint finish (fingernail polish comes in an amazing assortment of colors and is often easier to find than regular touch-up paint... FYI, I even know someone who painted an entire frame with fingernail polish).

If this doesn't do the trick, it might be that the bars are scratched more. In general you want to be very careful with any carbon part that has scratches on it because carbon as a material is highly notch sensitive. This means that if you scratch it deep enough you create a weak point in the piece (a notch) that will usually result in the part breaking right at the scratch/notch.

The tricky part is figuring out what's a minor scratch and what's a real notch you need to be concerned about. You can usually do this with a good magnifying glass. A notch to be worried about looks like a break, or if you have a strong magnifying glass, it looks like a small Grand Canyon in your part where you can see down into the granular structure of your part (your handlebar). A scratch won't look like this. It will be a shallow indentation. Here are lots more tips on caring for carbon bicyles and components.

In most cases what you are describing from the grips on your bar will be scratches in the clear coat on your handlebars, not a real notch. But, I just wanted to make this real clear since you wouldn't want to sell anyone a handlebar and then have it break when they are riding. An example of a notch issue is when you overtighten levers on the bars, or if the levers are slightly loose and they move around on the bars and actually cut into the carbon fibers of the bar. That wouldn't be good.

For simple surface scratches in the clear coat the fix is relatively easy:
1. Get some fine wet-sanding emery cloth at a place like The Home Depot. 600 or 400 grit will work fine. You only need a few pieces.
2. Put the emery cloth in a pan of water to wet it.
3. Gently sand the bars until the scratches are removed. As you sand you will roughen the clear coat on there and you won't be able to see the scratch you're working to remove. To check how it's coming along, wipe the bar with a damp rag. This will show how you are doing removing the scratches. Stop sanding when the bar is nice and smooth and the scratches are gone. Keep in mind that I am assuming these are only surface scratches. It will take too much sanding to remove deep scratches and probably not worth the trouble since they will be covered with grips/levers anyway. I would just cover deeper scratches with the clear nail polish I mentions, but again, be sure they are only scratches, not structural damage.
4. Once the bars are nice and scratch-free, clean the sanded areas completely with something like rubbing alcohol that leaves them clean and residue free.
5. To finish the job, you next spray the bars with a clear coat of enamel. You can get this at Home Depot when you pick up the 400/600 wet/dry emery cloth. Get clear coat enamel. It can be a little hard to find. You don't want what's used on wood. You want an auto body clear coat enamel paint. It's best sprayed when it's warm out, about 70 degrees. One light coat will usually do it. It dries quick.

If you do all this right the bars will look brand new when you're done. One more thing: you want wet sandpaper and to sand when wet because you need to prevent any carbon dust from being created. You don't want to breathe carbon dust. Sanding with wet paper will prevent any issues.

Hope this helps! The photo with this show carbon dropped handlebars as an example, because I use the procedure outlined above to remove even large logos on bars like these and it works perfectly (sometimes the logos don't look right with a certain frame color or if you use a stem that's not that same brand).

Jim
PS: A reader named Bill offered these great suggestions, "A better way for the carbon scratches is to go to a motorcycle shop. Buy a tube of Scratch X. It is designed for helmet faceshields and windshields. It will polish out a surface scratch quickly and leave it as new. Also in auto paint stores, 3M makes a clear-coat polish that does the same thing." Thanks Mike!
---------------------------------------------------

Q: Hey Jim,
I have a blast reading and learning from your site. Thanks so much for all the great info! My wife has a Raleigh Venture 7-speed comfort bike. She wants more gears, but doesn't want to buy a new bike. I think she should, but she loves her red color that is no longer offered by Raleigh on the 2009's. I have been wondering if I can modify the bike to make it a 21 speed?. Is it as easy as adding a 3-speed shifter on the left handle, a front derailleur, triple crankset, and new chain? Or is there much more involved?

I'd like to do the job myself, but don't know what it will require beyond these components. I can run the shifter cable and install the shifter myself, but don't know how hard or easy it would be for the front derailleur or crankset. Thanks for any advice you have.

Cheers,
Michael

A: Thanks for the kind words, Michael. I appreciate it. Adding gears is usually possible, but it depends on a few things. I checked out the Venture online and from what I can tell, I believe you could install a triple crank, front derailleur and shifter and be good to go. You might or might not need a new chain. It will depend on how large a chainring is on the bike now compared to the size of the large one on the triple.

It's not a difficult job to make this upgrade but you need to figure out what to buy to make sure it all works properly. There are some dimensions to get right. So, the easiest thing might be to have your local friendly bike shop figure this out and buy the parts from them to ensure you get stuff that will work right. One issue you need to check is the cable path. I know you mentioned that you can do this, but you need a way to run the cable/housing from the new shifter to the front derailleur.

I can't tell from the photo online if the Venture is setup for that or if you'll have to come up with your own solution (clamps, zip ties, etc.) Sometimes the manufacturers include this, sometimes not. It's details like this that the shop could tell you about just by looking, and then get you what you need. Front derailleur clamp size and cable pull are other details, plus you'll want the correct bottom bracket for your frame and the triple crank you choose.

Something to think about is what you really gain by upgrading to a triple crankset. Right now the bike probably has 7 gears, some pretty easy ones, some pretty hard ones. Typically if you go to a triple you will end up with several easier and harder gears. If you knew that all your wife wanted was to make the bike easier to pedal, you could probably provide that by simply installing a larger cassette on the rear wheel. That would be a lot cheaper and easier than converting to a triple chainring setup and it would give her the gears she needed if all she really wants is easier pedaling gears.

Hope this helps and have fun dialing in the bike,
Jim
---------------------------------------------------------------

Q: Jim:
I wonder if you can help me. I have an old Mavic sew-up rim (probably 25 to 30 years old) that I would like to change over to a clincher. I don't know whether to buy a 700c rim or a 27 inch rim. It has 36 spokes if that makes any difference. Any thoughts?

Thanks,
Bruce

A: Hi Bruce,
Sure! You should get a 700c rim. That is the same size as your sew-up rim. A 27-inch rim is actually larger diameter so your brake pads won't line up the same - they might not even brake anymore. As long as you go with a 700c, the "new" wheel will fit almost exactly the same as the old one. Also, it will be the same size as the other wheel on your bike - even more important probably ;-)

Hope this helps!
Jim
---------------------------------------------------

Q: Hello,
I have a question about my bicycle chain. I use my bike to ride to the train station and then I have to leave it there all day until I get back from work. This make it hard to keep clean. I initially had a big problem with black greasy buildup on my chain. I was told that my problem could be fixed by using silicon based lubricant, and only use one or two drops. I cleaned my chain and switched to this lubricant, and the greasy buildup problem went away. Unfortunately, now my chain is prone to rust.

I was told that the way to keep rust off the chain was to keep it “well lubricated.” I think this would then put me back in the first situation again with the greasy buildup. Is there some way out of this catch 22?

Puzzled,
Larry

A: It sounds to me like you were using too much lube and then you switched to too little lube, Larry, hence the rust problem. You want to keep your chain fully lubed but not too lubed. The key is to clean it once so there's no grimy buildup and then lube each link (every link, all around the chain) with one drop each, of good quality bicycle chain lube suited to the conditions you ride in. Your local bike shop should be able to recommend a lube that's perfect for you or ask riding friends in your area what they use and check out their chains to see how they look too.

To apply, drip the lube on the links on the lower run of chain (beneath the chainstay) and do it while pedaling slowly backwards so the rear wheel is not spinning, or else the rear wheel will throw any lube that mistakenly gets on it across the room. After you lube the chain let it sit overnight so it soaks in and dries. Then wipe off the excess in the morning before riding.

Most people who ride every day for commuting or fun can ride for about 2 weeks before having to repeat the lubing process. But, you never want the chain squeaking or rusting. Those are signs of not enough lube and you'll want to relube. Greasy buildups are signs of overlubing so clean again and lube less. There's a learning curve to figuring this out and you have to find a lube that works. I use ProGold ProLink Chain lube, which is expensive but works nicely in our rather dry conditions here in Santa Cruz, California. I use it on my road bike that sees heavy use. And, I relube about every 2 weeks. I also take care to wipe the chain down before and after lubing to get any buildup off. That works well. You have to keep after it, lubing, cleaning, lubing some more, and so on, but it's pretty routine after awhile and your chain won't squeak or rust.

To a clean, smooth, quiet drivetrain,
Jim
---------------------------------------------------

Thursday, March 19, 2009

Q&A: Seatpost binder bolt torque, creaky seat, bent derailleur hanger

Q: I just overtightened a seatpost clamp and stripped the threads. I got a new one now. How much torque can I put on this clamp? I have a Thomson aluminum seatpost.

Thanks,
Steve

A: Hi Steve,
Unfortunately it's not easy to give you a torque and be sure that it's right for your frame, clamp and bolt. I wouldn't tighten it with a torque wrench unless I had the information from the company that made those parts. Instead, what I'd do is make sure the bolt is lubed with grease, and then tighten it carefully. It only needs to be tight enough to hold the seatpost from slipping. You tighten the bolt and then you test your seatpost tightness by grabbing the seat and trying to turn it to see if the post is tight yet. Overtightening is very common so go a little at a time until the seatpost is held fast. That's the best way to go about it. If you have a torque wrench you could then check to find out what torque you tightened it to and then use your torque wrench in the future since you have a number for your exact setup.

If you would like to investigate torque settings further, there is a good page on Park Tool's site here: http://www.parktool.com/repair/readhowto.asp?id=88 In it they recommend 36
to 60 inch pounds of torque for seatpost binder bolts, but caution to use care. Also the seatpost bolt torque is marked as coming from Campagnolo, so it may not be correct for your frame, bolt and clamp.

Tightening carefully is the best way to go usually,
Jim
-------------------------------------------------

Q: Hi Jim,
I emailed you some time ago in relation to a creaking seat, which I've now managed to solve. FYI, It turns out the Fizik Arione saddle with Ti rails sits on a FSA Carbon K-Force seatpost had gathered dust under the aluminium cradle and was causing the creak. I stripped the seatpost and applied Silicon spray to the area, dried it completely and now presto, no noise.

In any case, Jim I'm emailing you since last week I fell off my bike onto tram lines here in Melbourne, Australia (we have plenty of them). It was a cold and miserable day and I got caught in the rain and my front wheel slipped on the wet track and down I went.

I took the bike to my mechanic. It is a carbon fibre Basso Laguna. The rear derailleur appears to be ok, though the mechanic mentioned that this had been the third time he had to straighten the rear dropout/hanger. He suggested I would need to get a new one, but I can't seem to find one here in Australia. The local distributor is away at the Taiwan bike show and not contactable. Any suggestions? Do you think after 3 alignments, the hanger would need replacing?

Regards,
Tony

A: Happy to hear about your seat (thanks for sharing the tip), but sorry to hear about your crash, Tony. Glad you're okay. The mechanic who fixed the derailleur hanger should have a feel for how weak it is now. They get weaker with each alignment but as long as they stay stiff enough to hold the derailleur steady they will keep working. I would think you could keep
riding with it and in the meantime order a backup so that you can change it out when that comes in. The company I know that makes the best assortment is Wheels Manufacturing. Your bike shop should be able to order from them (they don't sell direct to consumers). You could also order them online at http://www.derailleurhanger.com/

I like to keep a backup on hand for my Cervelo and I'd recommend you get one to be safe should your bike start shifting poorly, a sign that the hanger is too soft and getting bent with every little bump.

Hope this helps,
Jim
-------------------------------------------------

Tuesday, March 10, 2009

Q&A: Indoor trainers, Cliff House tandem

Q: Hi Jim - I have an indoor trainer question that I always wanted to ask. How tight should you crank the roller against the tire? I think that I probably have it too tight.

Thanks!
DP
A: That's a good question because it's easy to get it too loose or too tight and how you set it effects traction and tire wear. Ideally you want to get it just tight enough so that the roller doesn't lose traction when you pedal hard. If you get squeaking it's because it's not tight enough and the tire is slipping. (Be sure to first fully inflate your tire.)

Of course, whether it squeaks or not during pedaling depends on how hard you ride on your trainer. If you apply steady pressure on the pedals the roller usually won't slip even if it's not overly tight. But, if you're doing repeats (intervals) on the trainer, where you ride easy then accelerate hard, and repeat, you will need it tighter against the tire so it doesn't slip.

I usually make sure my tires are fully inflated, mount the bike on the trainer and then screw the roller against the tire (I ride a Kurt Kinetic Rock & Roll Trainer). I then grab the wheel and pull it up and down, and tighten the roller until there's no slipping at all. At this setting you'll have the traction needed without pressing the roller so tighly against the tire that you wear it out too soon.

Keep in mind that all trainers wear tires more quickly so I now use a special tire made only for trainer use, Continental's Home Trainer. It's made of a harder rubber designed to hold up to the trainer roller so that you can save your good tires for road riding (the Home Trainer is not for outdoor use). Some people simply install inexpensive tires on their bike for use on the trainer instead.

You didn't ask me about something else that's also important, and that's how tightly you mount your bike in the trainer. Most have adjustable mounts that hold the rear end of the bicycle off the ground by clamping the rear wheel quick release. It's important not to set this clamp too tight too. The way to get it right is to check how easily the wheel spins once you've mounted your bike in the trainer but before you've tightened the roller against the tire. Just give the wheel a push and make sure it spins freely. If it moves 1/2 turn and stops, it's probably because you have your bike clamped in the trainer too tightly.

It's pretty easy on most of them to set the clamp so that it puts so much pressure on your bike that it actually tightens the hub bearings on your rear wheel. That will make it harder to pedal and it can also cause bearing damage, so check for that and fine-tune your trainer clamp until it holds the bicycle securely but doesn't compress the bearings.

Lastly, people sometimes ask me if trainers can hurt bicycles. They worry that the bike is held in such a way that you might put forces on the bike on the trainer that could weaken or damage the frame or parts. It's a good question because there are all kinds of different trainer designs, but I've never seen one that could hurt your bike as long as you follow the instructions and mount your bike correctly. As I mentioned, you can wear tires more quickly and put too much pressure on the rear wheel bearings, but the frame and components aren't at risk from the trainer. You should take one precaution, though. Be sure to drape a towel over your bike if you're riding hard enough to start sweating because that can drip on your frame and components and over time, damage things via corrosion.

To great indoor rides!
Jim
-------------------------------------------------------------

Q: Hi Jim,

I maintain a website about the famous Cliff House and I found a bicycle photo I was wondering if you could help me with. I'm curious what's with the double handlebar? FYI: This photo was definitely taken between 1896 and 1907 (based on the building).

Thanks for any help you can provide. I'll add it to the photo.
Gary

A: Cool photo, Gary. There are 2 handlebars on that bike because it's a tandem bike, a bicycle built for two. It's hard to see because it blends in with the man's clothes, but there's also a second seat on the bike. So, I would call that a circa 1900 men's tandem bicycles. One of the interesting features of tandems of this era is that they are steered by the person in back.
Today's tandem bikes are almost always steered from the front. To steer it from the back, the one in your photo has a linkage that lets the rear handlebars move the front wheel. You can see the linkage bar on the side of the frame. The person in front just goes along for the ride as the person in back steers. The people that rode this tandem had to be pretty darn fit because it only has one sprocket on the back and it's pretty small meaning a hard-to-pedal gear, especially if they were to have to ride up any of San Francisco's steep hills.
Those are a few notes that I hope are helpful. I'm afraid I can't see anything on the bike that tips me off to the brand or model. I would say that the man is dressed very nicely in cycling knickers, knee socks, leather shoes, gloves and a tidy cap. He appears to have the latest cycling fashions and may have been fairly well-to-do since the tandem and the cycling gear was expensive even in 1900, and a way to show off your stature in society. I suspect he was riding with another man, though, not a woman, since the front of the bike is a man's frame. If he was with a woman, the front of the bike would have had a sloping frame for the woman to get on and off easily.

If anyone sees this and can identify the make of the bike I'll keep you posted,
Jim
----------------------------------------

Sunday, March 1, 2009

Q&A: Broken spokes on the road, 3-sp shifter, brake pads for wet weather

FiberFix emergency bicycle spoke
Q: Jim - good morning. I recently broke a non drive-side spoke on my Shimano Dura-Ace rear wheel on a ride. I was wondering if you had a source for replacement spokes and any advice on dealing with this when you're out on a ride. I had to call home for a ride since the wheel was too warped to straighten with the spoke missing.

Thank you
Chris


A: Hi Chris,
With all the low spoke-count wheels on the road today, broken spokes are more of a problem. When we had 32 spokes on most wheels you could break a spoke and still get home because there were enough other spokes to keep the wheel from coming too far out of true. As you discovered with your wheel, today's aero hoops go a lot more out of true when a spoke breaks and it can make the wheel wobble so badly it hits the frame rendering your bicycle unrideable, meaning you have to call for help.

I often ride with friends and we're all on modern low spoke-count wheels so I try to always carry a repair spoke called a FiberFix (photo). It's essentially a super-strong little aramid-fiber "cable" and end, that fits almost all wheels and takes the place of the broken spoke, allowing you to retension the wheel and keep riding. You can learn all about the FiberFix spoke and order one at Peter White's great site.

If you don't have something like this on a ride, you can sometimes temporarily fix a broken spoke if you're lucky. It depends on how/where the spoke broke, but if you can tie the ends of the spoke together by bending them and joining them with a piece of wire/string/zip tie (from your repair kit or found beside the road), or whatever you have handy, you might be able to get the wheel true enough to at least keep riding on it.

Now, on getting a replacement spoke, I'd recommend buying several so you have backups next time. You could try your local bike shop. Or, if they don't have them and your Shimano wheels are new, you might start by calling Shimano's tech line, telling them what happened and asking them if they could get you spokes 949.951.5003. The spokes aren't supposed to break and I think they'll be eager to get you setup with a replacements if you have new Dura-Ace wheels. You can tell them you already went to local bike shops and they didn't have the spokes.

Or, if your local bike shop has Shimano Dura-Ace wheels for sale, you could try asking them if they'd be willing to rob a spoke for you. If they're the shop where you bought the wheel that's not too much to ask and it's no big deal to remove and replace one spoke.

I don't know if they carry the DA spokes, but I've also had good luck with ExcelSports.com when I need specialty parts not available locally. You can call them at 800.627.6664.

Another workaround if you need it that might work is to see if a regular spoke can be put in for now. The first thing would be to unscrew the DA spoke at the rim and see if a basic DT spoke will thread into the DA nipple in the rim. If it does, you can try this: Find a shop with a Phil Wood spoke tool - a professional tool some shops have that puts perfect threads on spokes. If you can find one, they should be able to use it to make you a spoke that will work temporarily. The DA spokes are threaded on both ends. So they can take the tool and take a nice DT spoke and cut the head off and thread that end, too. This way you'll have a spoke threaded on both ends that should fit the nipples on your DA wheel. (Of course, this assumes that the nipples didn't break.)

One of these ideas should get you going. Good luck!
Jim
-----------------------------------------------------

Q: My friend has a cool old Japanese 3-speed bicycle missing the trigger shifter. Will an old Sturmey-Archer trigger shifter work, or is the cable pull different?

Sturmey-Archer 3-speed hub and shifter from 1959A: The answer to your question depends on what type of 3-speed hub you have on that Japanese bike. The easiest way to tell is to look at the way the shift cable connects. If it's connected to a little threaded rod with small chain links on it (what Sturmey called the indicator - see photo), you should have a Japanese clone of a Sturmey-Archer hub and I believe a Sturmey trigger will work. The cable will have the correct end at the handlebar, too (long, cylindrical) to fit in the Sturmey trigger and the trigger should pull the right amount of cable with each click.

But, if you see what's referred to as a "toggle" mechanism attached to the rear axle, a small knuckle-like metal apparatus that the cable attaches to, the handlebar end of the cable will not work in the Sturmey shifter, so you'll need to search for a Shimano-type shifter.
Hope this helps,
Jim
--------------------------------------------------------

Q: Hello Jim – I commute to work via bike several times a week. As you are aware on a road bike when it rains or on wet pavement the brakes will slow but not stop. Is it possible or advisable to use the longer mountain bike brake pads? I have Shimano 105 brakes, 9 speed drivetrain w/ triple, 700x25 tires, Mavic rims.

Regards,
David

A: Hi David,
I wouldn't recommending going to longer/larger pads, as they usually won't fit very well with the tighter clearance on road bikes. Instead, I would try some brake pads made for wet weather as they are designed to grip better when it's rainy. You might try Kool Stop pads and see if they don't work a lot better than what you have.

A lot of bike shops carry these pads, so you might be able to find them locally with a few phone calls. And, they'll slip right into your brake pad holders. You want the pads that fit your Shimano 105 brakes and the models made for wet weather.

Be sure to clean your rims regularly when you ride in the rain a lot, too, as the crud and grime from the wet roads can leave a residue on the rims that reduces friction. Simple rubbing alcohol works great. Just wet a rag with it and wipe the rims completely on both sides and that'll keep the rims nice and grippy.

To better rainy-day braking,
Jim
---------------------------------------------------------