Tuesday, January 2, 2018

Q&A: Dealing with disc brake rubbing and bent rotors

A couple of questions about common disc brake issues came in recently. With discs on so many different bicycle types today, it's a good topic to kick off 2018. Happy New Year!

Q: "My gravel grinder road bike has a dragging disc brake. I don't really feel it when riding. But, if I pick up the bicycle and spin the wheel, it's obvious the pads are rubbing because the wheel stops. This has to be costing me energy and speed on rides, so it's frustrating. I've had a few mechanics try to fix it. But, no one can seem to stop it rubbing. Can you help?"

Yuri

A: The type of rubbing Yuri describes can be missed when riding because it’s slight. But, as he mentions, if you lift the wheel that’s rubbing off the ground and give it a spin, you’ll realize straight away that the rotor (the metal disc attached to the wheel) is slightly rubbing, because the wheel will stop spinning much more quickly than the other wheel (unless it’s rubbing, too).

This isn't the type of rubbing caused by a bent rotor. That creates a major rub that’s easy to see because the rotor wobbles when the wheel is spinning. For information on fixing bent rotors, see the second question (below this one).

The type of rubbing I’m explaining how to fix here happens on straight rotors. It’s highly annoying because, while it’s only slightly dragging, it’s constantly slowing you down and wasting your energy. You can try squeezing and releasing the brake lever repeatedly, removing the wheel and reinserting it, gently flexing the rotor to try to push the rubbing pad away, even loosening and repositioning the caliper – but the brake will usually still rub as soon as you brake again.

Fortunately, there’s a fix for this problem that almost anyone can do. All you need is the right wrench to remove the brake caliper from the frame and an ordinary business card. Don’t worry. You do NOT need to disconnect the brake hose/cable from the brake caliper or change any brake adjustments.

Tip: When working on disc brakes it's best to keep all oils (even from your hands), greases, lubes, etc. away from the brake pads and rotors. Lubes can contaminate and ruin the braking. If you make this mistake, to fix it, you may need to replace the brake pads and super clean the rotors.

To fix the rubbing, follow these 5 easy steps.

1. Remove the rubbing caliper from the frame by loosening and removing the two bolts holding the caliper in place (turn the bolts counterclockwise).

Before taking the bolts all the way out, be sure to note (take a photo) which one goes where and the order of any parts between the bolt head and the brake caliper. There may be washers or locking washers and one bolt may be different than the other. Be 100% sure you know exactly how the bolts and any parts go back on so you can get it right when you reinstall the caliper.

2. Now, hold the removed caliper in your hand. It’s still attached to the brake hose/cable, but there’s room to work on it.

Next, fold an ordinary business card in half and slip it inside the caliper as shown in the photo below. Depending on the size of the card, you might need to cut it down to fit.

3. Once the card is sized right and in place, wiggle and push the caliper back over the rotor so that the business card is in between the rotor on both sides and the brake pads, too (they’re tucked inside the brake caliper).

While keeping the caliper on the rotor, turn the wheel so that the caliper lines up to the bolt holes in the frame. Then, put the bolts back through the caliper, using care to put the bolts in the right place and any washers or tension devices in the right place, too. Refer to your photo. Screw the bolts clockwise until the caliper is loosely mounted back on the frame with the business card still in place inside the caliper.

4. Now, squeeze the brake lever and keep it squeezed while tightening both brake caliper bolts fully. If you're working on the rear brake, you might not be able to reach the bolts while holding the brake on.

So, ask a friend to help, or wrap something around the brake lever that keeps it firmly squeezed, like a toe strap or strong elastic band - the Bike Brake is handy for this.

5. Now that the caliper is back on the frame and tight, release the brake lever and squeeze it a couple of times as if braking.

Then, turn the wheel while holding onto the edge of the business card and the card will rotate with the rotor and come out. Once the card is out, you should find that your brake works nicely again with no more annoying rubbing!

Note that, instead of removing the caliper, you can try just loosening the caliper bolts. Then, removing the wheel and folding the business card over the rotor and reinstalling the wall and following steps 4 and 5 above.

The only thing is that it can be tricky on some bikes to get the rotor back into the brake caliper when the business card is on it - and to keep the business card in the right place on the rotor so that the card ends up exactly between all 3 things (rotor and both pads). You can do it if you're patient and careful but if you're not, you could get the card in the wrong place or even knock a pad loose.

In comparison, when you push the caliper over the rotor you can see what you're doing, the card will stay were you put it inside the caliper and it's less likely you will damage anything. But, both ways can work.

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Q: "Jim, not sure how this happened, but I bent my disc brake rotor. I know its bent because I can see the wobble and it wasn't like this when it was new. Is there a way to straighten bent rotors or do I need to have it replaced?"

Charles in the UK

Great question, Charles. Let's look at how rotors get bent first.

Causes
Rotors are the round, thin metal plates that attach to the wheel hubs. When you’re braking, the brake pads inside the brake calipers squeeze the rotors, providing excellent all-conditions slowing and stopping power.

If you’re lucky, your rotors will remain almost perfectly straight and you’ll never have to worry about them until they’re worn out, which can take a long time. But, if you’re unlucky, many things can bend the rotors.

For example, you could have a stick come up, get stuck in and bend the rotor. Or, on a long descent, you might hold your brakes on too long and heat a rotor enough that it warps. Another one is having someone at a rest stop mistakenly lean their bike against yours without realizing that their pedal is going to slam into your rotor when they let go.

Fortunately, these types of bends are usually fixable. What’s required is straightening the rotor. It’s a good skill to have because it’ll save money and let you keep riding instead of having to shop for new parts.

Tip: You can always replace bent rotors with new ones if you can’t or don’t want to try straightening them. They aren’t overly expensive. Just be sure to do your homework and get the same type you had.

Inspecting rotors
Before assuming a rotor is bent, check that there aren’t other problems causing it to only appear bent. Rotors are held on with lockrings or bolts. If these loosen, a rotor can wobble and look warped when all that’s needed is tightening the rotor bolts or lockring.

You might also have a wheel that’s not fully tightened in the frame. Check the quick release or through-axles to make sure. Or, a wheel might be off-center in the frame or fork, which can make the rotor look too close to the brake, causing you to think it’s bent. In that case, all that’s needed is loosening and centering the wheel.

Another glitch that can make a rotor wobble when it’s not bent is loose wheel bearings. To check for this, grip the wheel near the fork or frame stays (rear wheel) and push and pull gently sideways.

If the wheel bearings are correctly adjusted, the wheel will not move side to side when you do this test. But, with loose bearings, a wheel will move, and sometimes a lot. The cure is to remove the wheel and adjust the bearings to eliminate any play.

When inspecting rotors, if yours has a compound bend, or is bent so badly that it almost has a crease or fold in it, it is probably beyond repair. The bends that are fixable can be significant, but only smooth bends, not actual damage to the rotor. So, if you see twisted or folded or crunched rotors, you should replace them because they’re likely beyond straightening.

Straightening
Once you’ve determined that you for sure have a bent rotor and not a seriously damaged one, you can try to straighten it – or you can say “true it.” It’s a trial-and-error process that takes practice to master. It’s not difficult, but it can be frustrating and require patience and a good eye.

You can true rotors while the wheel is on the bike. For a tool, I use and highly recommend Park Tool’s DT-2 Rotor Truing Fork (about $20). You can see in the photo how this tool has two ends that slip over the rotor for excellent and precise leverage.

Park’s tool is heavy and fits perfectly so as not to damage the rotor even when you pry on it pretty hard. That’s usually what it takes to get a wobble out. If you’re new at it, you’ll get a feel for how you have to bend the rotor well beyond where you thought it would go straight to get it to improve, because the metal wants to rebound more than it seems it would.

You can slip the top of the tool over the top of the rotor to pull out or push in to remove a side-to-side wobble. You can also use the end with the short horizontal slot to remove a twist in the rotor by slipping that notch over the twist and pulling or pushing the tool as you hold it 90 degrees to the rotor. Another use of the horizontal slot is to slip it through the rotor and onto one of its “legs” to straighten lower bends.

Don’t rush it, and pay attention to the changes you’re making, and you can get good at straightening rotors. If it helps, you can mark the bent area of the rotor so you can keep track of your progress. Just be sure not to use anything that’ll compromise the braking surfaces.

Sighting the wobbles
One of the challenges of straightening rotors is seeing/finding the wobbles. With the wheels on the bike, you can sometimes sight through the brake and watch the rotor come through. If so, you’ll be able to see the rotor move left and right in relation to the brake pads, and be able to stop the wheel at that point. You then rotate the wheel to bring the wobble outside the brake so you can straighten just the right spot.

If you’re having trouble seeing the wobble through the brake, try putting a piece of white paper in your line of vision behind the brake caliper – or have a friend hold one up. Another trick that can work is holding a flashlight just so, to light the inside of the brake so that you can spot the bends.

Reading further, you’ll learn about the only tools I’m aware of specifically designed to make rotor truing much easier and super accurate. They’re great tools. But if they’re beyond your budget or needs, you could maybe copy how they work and rig up a pointer on your fork or frame.

Something as simple as a pencil for the pointer and a rubber band to hold it in place might do the trick in a pinch. If you come up with something that works well, please comment below and share it.

The gold standard in rotor truing tools
If you’re straightening rotors on a regular basis, you can save yourself a lot of time and do an even better job truing them with one or two more cool tools from Park, their DT-3 Rotor Truing Gauge (about $40) and DT-3I.2 Dial Indicator for DT-3 (about $40). See the photo.

Note that in order to use the DT-3 and DT-3I.2 Truing Gauges, the wheel with the bent rotor is removed from the bicycle and placed in either Park’s TS-4, TS-2.2, or TS-2 Professional Wheel Truing Stand ($230 - $372), which are all pre-drilled for the gauge to bolt onto.

If you have another brand of truing stand, it might be possible to drill it to accept Park’s gauges.

With the wheel held securely in a truing stand with one or both of Park’s gauges attached (the photo shows both), there’s no need to try to sight through the brake caliper. Instead, you locate the wobble with the gauge’s indicator and straighten each wobble with the Park Truing Fork.

It still takes time and patience to find and true wobbles, but because the indicator shows you exactly how true the rotor is becoming, the trial and error is greatly reduced. It’s super satisfying when you end up with nice true rotor and a disc brake that works perfectly again.

Here’s an excellent video on rotor truing with Park Tool tech whiz Calvin Jones


Here's hoping your disc brakes work like a champ from here on,
Jim

Monday, February 6, 2017

PRODUCT REVIEW - Wheel Fanatyk Mitutoyo Digital Spoke Tensiometer

Wheel Fanatyk Tensiometer Sets a New Gold Standard

A few months back, in my RoadBikeRider.com Tech Talk column, about fixing wheels on which all the spokes loosened, I mentioned I would look at some of the new cutting edge tools today’s wheel builders and wheel companies are using to make better wheels than ever.

Wheel Fanatyk’s Mitutoyo Digital Tensiometer, that I review here, is one of these tools.

I needed an accurate spoke tensiometer because I’m now building carbon and aluminum wheels for a local components company (over 60 pairs to date). One of the requirements is hitting the tensions specified by the engineers designing each wheel model.

I’ve used a Wheelsmith Tensiometer since 1988. It’s a nice tool, but has never been recalibrated. And, I’m not sure how accurate its readings are any more. Note that Wheel Fanatyk recalibrates Wheelsmith tensiometers.

Comparing the Wheel Fanatyk gauge to my trusty Wheelsmith's (photo below), you can see that the Wheel Fanatyk provides a digital readout in hundredths of a mm, while the Wheelsmith shows spoke deflection on a vernier gauge.

In the example shown, the two lines closest to lining up are almost at the 50 mark, which means the deflection of the spoke is somewhere past 45.

If you compare readings on both tools on the same spoke on a wheel (note that the photos above and below are on different wheels), you appreciate right away having an exact number to 1/100th of a mm, and not having to estimate spoke deflection by estimating where the lines align on a vernier gauge.

The right tension makes a good wheel
Nothing is more important for the integrity of bicycle wheels than spoke tension. Too loose or tight and wheels are unstable, or worse, they may fail. In an extreme example, a pair of classic Ghisallo wood-rim wheels I over-tensioned as a wood-rim newbie in the 80s - before owning a tensiometer - rode fine for a couple of weeks and then imploded when both rims broke to pieces.

It's not easy feeling for correct tension with your hands. Spokes can feel very tight and still not be anywhere near tight enough for a wheel to remain tight and true over the long haul. And since rear wheels and now front wheels with disc brakes are built with uneven spoke tension on the left and right, it's more important than ever to ensure the spokes are tight enough to make a great wheel.

To explain, if you have no way to measure the spoke tension accurately, you could be fooled into thinking the spokes are tight enough because the dished spokes feel tight when squeezed (the "dished" spokes are on the right side for rear wheels and on the left side for disc front wheels). However, if the dished spokes actually aren't tight enough, the non-dished side spokes will be too loose. And those are the ones that usually loosen when ridden causing the wheel to lose tension and go out of true on the road/trail.

Because Ric Hjertberg is a longtime friend, who owned Wheelsmith and now owns Wheel Fanatyk, I decided to look into his newer and superior tensiometer. Ric sent me the Mitutoyo Digital along with the optional Foot Pedal Data Output System to try out. Let’s look at the Tensiometer first.

A Jobst Brandt design
The Wheel Fanatyk Tensiometer was designed by the late Jobst Brandt, a bicycle God and engineer who worked for Porsche, Hewlett-Packard and Avocet during his career (Brandt was the genius who designed the first cyclometer that accurately measured cumulative elevation gain in the Avocet 50). Brandt also wrote the best book on wheelbuilding, The Bicycle Wheel.

What makes the Wheel Fanatyk Tensiometer so accurate is that Brandt’s design is barely affected by spoke thickness variance. Spokes vary due to material, how they’re manufactured, and plating and painting can affect them, too. Ric explained, “The Wheel Fanatyk is unique among commercial spoke tools because it does not measure across the spoke thickness, it only detects deflection.”

Jobst Brandt in 2005 (Bill Bushnell photo)
Brandt’s tool bends the spoke between three points with a constant low spring force. Bearings on either end of the tool minimize friction where they rest on the spoke. A Delrin (a hard nylon) “anvil” pushes the spoke against the gauge’s probe for tension readings. There’s a button on the gauge to zero it if needed before taking a reading on the next spoke.

Holding the tensiometer is impressive. It’s a weighty 311 grams (11 ounces) and obviously built of quality materials throughout (Ric hand assembles each one). There are laser-etched nameplates; one with the serial number. The jewel is the Mitutoyo gauge from one of leaders in measuring instruments since 1934. It sits protected inside the tool’s triangular profile and displays reading in 10mm tall numbers on the large LCD screen.

Using the Tensiometer
SpokeService tension charts
It took a little practice to get the knack of holding the Tensiometer on the spoke just right to not get incorrect readings on the gauge. If I put any hand pressure on the tool, it flexed the spoke and messed up the reading. With more use, I learned to just rest the tool on the spoke and completely relax the hand for accurate readings every time.

Once I got the technique down to gently rest the meter on spokes, it was simple and fast to go around wheels taking readings. You measure the right and left spokes from the same side of the wheel. There’s no need to switch the tool to the other hand or reverse the wheel.

While you can zero the reading for each spoke, most of the time the gauge reads zero once in position on the spoke. And, I realized that even if it starts with a reading, that number is so low that if you don’t want to zero the gauge before taking the reading, it’s not a significant discrepancy and easy to subtract in your head.

Watch this video of the Tensiometer in action.

Converting deflection to tension
Tension chart
Once you have a few readings there is one last step because the gauge shows the distance the spoke deflects in tenths of a mm. Wheel designers and engineers, however, specify tension with kgf (kilogram-force), so that’s the number needed to be sure wheels are tight enough.

In order to “translate” the deflection to a tension reading, you refer to a chart that comes with the Tensiometer (photo). By looking at the column showing the type of spoke on the wheel you’re measuring you can find the reading shown for the spoke and see on the chart what the kgf reading is.

For example, if the gauge reads .30 (the spoke deflects .30 of a mm), the chart shows a kgf of 119 on a spoke with 1.8mm thickness.

Using the Foot Pedal Data Output System
The way the Foot Pedal Data Output System works is by plugging into the Tensiometer and a computer so that you can easily record the tension of each spoke in a spreadsheet. The free online place to do this recommended by Ric is SpokeService

As you take each tension reading with the gauge, you step on the foot pedal and the tension number magically appears in the chart plus the cursor moves to the next cell. Once you’ve measured all the spokes on both sides you can view a wheel map showing the tension highs and lows around the rim. You can save and/or print the wheel’s specs to put with the finished wheel, too.

If you don’t have the Foot Pedal system, you can still enter reading by hand into the online utility. A screenshot of the SpokeService charts is above.

While most cyclists may never need a spoke tensiometer as accurate as Wheel Fanatyk’s, it does set the gold standard for wheelbuilders. If you’re a hobby wheelman or want to learn, this tool is the ultimate for getting tensions right. It’s also the best tool for checking new wheels you’re considering buying, which is why it’s used by major wheel makers. This helps ensure the highest quality builds, which is a great thing with all the new wheel components and new wheel specifications coming out all the time.

Price: $348 for Mitutoyo Digital Tensiometer. $98 for optional Foot Pedal Data Output System (There is also a Mitutoyo Dial Tensiometer: $280).

Saturday, December 31, 2016

Bike Video: Bicycle Culture by Design

Recently, I've been listening to and enjoying TED Talks podcasts. So far, I haven't heard one about bikes or cycling, so I had the idea to search for them on YouTube and found what I think is an excellent talk.

It's presented by "urban mobility expert" Mikael Colville-Andersen. It's only 15 minutes long and I think you'll enjoy what he has to say...


If you're reading this post in an email (rather than on the blog) you'll probably need to click this link to watch the video https://youtu.be/pX8zZdLw7cs

To better road designs for cycling everywhere,

Jim

Wednesday, December 7, 2016

Happy Holidays!

Happy Holidays cycling friends!
In celebration of this joyous time of year, here's some Christmas-themed vintage art to inspire you. With a little creativity, you can use it to make your favorite into a printed or digital card to send.

My favorite here is either the December 12, 1942 The New Yorker cover from my collection (think you could bring home the tree on your handlebars - I doubt I could?), or the Western Auto window shoppers reacting to the Western Flyer ("the most beautiful bike in town").

If you're shopping for cycling gifts, don't forget to visit your local bicycle shop in person and/or online. Be sure to ask them for suggestions, too. They'll know what's popular right now and what others are buying for gifts, too.

Wishing you a wonderful Christmas and New Year,
Jim





Wednesday, October 26, 2016

Be a Bicycle Vampire Hunter this Halloween

Happy Halloween!

In the spirit of the season, and with all due respect to Roman Polanski’s classic 1967 spoof The Fearless Vampire Killers, I'm sharing some simple tips to help you hunt for, find and terminate your bicycle vampires.

 

Unlike the fanged variety, two-wheel ghouls constantly suck your energy by making your bicycle harder to pedal. And like Dracula, they’re apt to appear at any time and can be hard to find. In fact, it’s rare that cyclists ever notice a vampire while riding or even rolling their bike.

To help, here’s an easy and fun 4-step check to perform about every 90 days during riding season (or a few days before any major ride or event; which gives you time to mend problems). Finding and fixing a vampire is one of the most satisfying repairs you can make. Start with the drivetrain since that’s bicycle vampires' favorite hiding place.

Note: I’m assuming your bicycle and components aren’t abused or worn out. If so, more inspection and repairs will likely be needed than covered here.

1. Chain check
Perhaps the most common energy-sucker is a dry chain. Few lubes last long if you ride regularly and in all weather conditions. And many roadies end up with not enough lube and a chain that’s stiff and dragging. 

You can identify a dry chain by its shiny rollers and metallic sound when turning the pedals. Don’t let the chain ever get like this. Keep it adequately lubed for how and where you ride. I'm partial to Pro Gold Pro Link chain lube. Another favorite chain lube is Boeshield T-9.

Park Tool's article on derailleur pulleys
2. Pulleys check
The two pulleys on the rear derailleur are the second hardest working wheels on your bike. Even if you keep your chain nicely lubed and apply a little to the pulleys, too, moisture can make its way inside and bind or even freeze one or both pulleys. 

Check for this by lifting the chain away from each pulley and flicking them with your finger to see if they spin freely and smoothly. If not, you can usually restore them by simply disassembling, cleaning and lubing all the parts.

Bottom brackets require special tools
3. Bottom bracket check
The bottom bracket (BB) is the bearing mechanism that the crankset spins on so it influences every pedal stroke. To check yours, shift onto your smallest chainring and then lift the chain off the ring and rest it on the frame. 

Now, hold one crankarm (not a pedal) and gently and slowly turn the crankarm feeling for tightness, roughness and smoothness in the BB. It should turn freely with a slight hydraulic resistance from the grease inside. If it’s tight, dry or rough, you probably need a new bottom bracket (or a bottom bracket overhaul if yours can be serviced). Follow this link and first figure out what type of BB you have and then look up the service procedure.

A cartridge bearing hub
4. Wheels check
Like the bottom bracket, the wheels spin on bearings, which when bad become vampires. It’s almost impossible to feel bearing issues with the wheels in place on the bicycle. So, to check if yours are failing, remove both wheels. 

Then hold each wheel’s axle (not the quick release - wheel clamping mechanism) between your fingers and turn it. Like the BB check, the wheel axles should turn freely and smoothly with a slight resistance from the grease inside the bearings. If the bearings feel tight, rough or dry, you need the hub bearings serviced. Follow this link and first determine which type of hubs you have and then look up the service procedure.

Here's hoping these tips are like garlic for your bike - and they keep those vampires away. Trick or treat!
Jim
All photos courtesy of Park Tool.

Tuesday, October 4, 2016

PRODUCT REVIEW: Pedro's Super Prestige Professional floor pump

Pedro’s Professional Pump performs up to its name

I like Pedro’s Super Prestige Professional Floor Pump (about $65) so much I bought two of them. One is in my home bike shop and the other lives in our new Lazy Daze RV. I’ve been using these pumps for a couple of years now and they still perform like new. I actually have a compressor in the shop, but these pumps work so well, I usually reach for them.

I like to point out good floor pumps because the most common maintenance task is topping off your tire pressure. And, unfortunately even many so-called “shop-quality” and expensive models perform sub-par and wear out surprisingly soon.

Common problems include difficulty achieving a leak-free fit between the pump head and valve - or having to change or adapt the head to fit a different valve; needing to push excessively hard to pump your tires fully; and ‘blow-back’ - which is when you push the pump handle down and it pops right back up with enough force and speed to explode out of the pump - in a worst-case scenario.

Nearly effortless pumping
There are no such issues with the Super Prestige. It features a heavy-duty steel base for stability, a wide ergonomic soft-grip handle and a small diameter, long steel barrel, which all make for nearly effortless pumping up road and mountain bike tires of all types and pressures.

Ultimate pump head
Instant airtight seal on all valves
The Super Prestige's best feature is the automatic pump head that you simply press on whatever type valve you have and then flip up the thumblock lever to lock the head on with an airtight seal. Pump heads are a common point of failure. 

I’ve never had the Pedro’s let me down and I’ve used it on dozens of different valves and valve extenders and adapters (for example, an adapter is required to inflate disc wheels - my favorite disc wheel valve adapter is Silca's Hiro). 

Presta or Schrader valve, you attach Pedro’s pump head and it holds fast and doesn’t leak.

Convenient long hose
Another sweet detail is the 39-inch (99cm) long hose. This comes in handy if you’re working on a bicycle in a repair stand and if you’re trying to inflate tires while bikes are up high on a rear vehicle rack, etc. The hose actually attaches to the pump beneath the top-mounted gauge rather than at the bottom where most other pumps attach them. That adds to the hose reach.

Pedro’s also includes a built-in hose holder to their pump that really works. Lesser pumps have holders that let the hose fall to the ground, which can lead to failure.

Super visible top-mounted gauge
The top-mounted gauge is close to you to read it more easily and has a knurled ring with a pointer that you turn and place on your target psi. Also, this stellar pump has a small button on the head that lets you bleed air to get the pressure just right.

All in all, if you’re looking for a great inflator, you’ll find it in Pedro’s Super Prestige. Here it is on Amazon though they have the wrong photo - it shows an older model.

Happy pumping!

Jim

Monday, September 5, 2016

Q&A: Saddle positioning when your seatpost won't cooperate, and a wheel from my past surfaces

Greetings from Santa Cruz, California where we just updated our always popular county Bikeways Map. Click the link to download and print a copy if you're headed here with your bikes, and you'll get around our busy beach town much more easily.

Here are some of the interesting bicycle technical questions that have come in since last we met, with my replies.

Q: "I just bought a Trek Madone 5.2 from a bike shop in California. I live in Florida. It was to replace my Madone 4.3 that got stolen last year. Long story short, without having the old bike to take measurement from for seat height, I figured them both being 47cm would make it the right size for me.

Well that was mostly true except the 5.2 has a seatmast not a seatpost that limits the height the seat can be lowered.

I need to drop the seat about 3cm to get comfortable in the saddle. I already have a low-profile seat with little room for lowering there without compromising comfort. I could do smaller cranks, I guess, but that would only drop me .5cm and that still leaves 2.5cm to go.

Trek said that I already have the shortest mast available. Any suggestions to get those last 2.5cm? Surely I can't be the first person to have this problem."

Joyce


A: Thanks for sending the photos of your Trek and its seatmast showing the design, and your saddle and how it's attached (above).

You're right that there's no easy way to lower the seatmast and since this is the shortest one Trek offers, you can't replace it either (I suppose you could have a custom one made but it would probably cost a small fortune and end up not matching the finish of the bicycle, either).

Another option might be to modify the seatmast in some way, such as cutting out a section, but that would be a job for a carbon repair company, such as Calfee Design - and might cost a fair amount, too.

But, luckily, there's another way to lower your seat. It's an old 'trick' mechanics have used forever. It works on almost all types of saddles that fit on seatposts via a certain type of clamp. That type of clamp has to be capable of being mounted upside/down.

Not all clamps will do this, but many will, including yours, as your before and after photos, show. Thanks for sending the photos after following my advice, so I can share them!

The key thing to look out for if you're inverting your seatpost clamp to lower a seat, is to check that when a person's weight is fully on the saddle, that the seat doesn't compress so far that it bottoms out on the clamp or seatpost. This can happen in some cases and you never want to have your seat bottoming out when you hit bumps because coming down against a solid piece of metal like that could hurt or even injure you. The saddle is designed to suspend you from impacts for comfort and protection.

Note that one of the most common uses of inverting seatpost/saddle clamps is on children's bicycles. Sometimes a child is too big/tall for one size bicycle but when you look at the next size, it's a touch too large. If that's the case and you can make the too-large bike fit by inverting the seat clamp, they'll be able to ride the bike safely and grow into it, too.

Keep reading for another seating issue you might run into...
Jim
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Q: The following is an email back-and-forth between a roadie named Phil and myself. Phil started the thread with this question: "After three years on my wonderful Lynskey R230, I have finally decided the seat (Brooks B17) should be further back. I switched to a 25mm setback seatpost (I used to have a zero setback Lynskey seatpost) but I still want to push the saddle back a bit more.

At this point I’m sure you are saying, “Phil, you should have bought a Large instead of a M/L Lynskey frame.” Yes, probably -  but I did not, so here I am.

The problem, of course, is that the rails – like most rails – on my Brooks saddle narrow as they approach the saddle nose. The bracket (i.e., the platform which grips the rails) is wider than the rails (note – this is Lynskey seatpost does not use the Enve inserts).

Solution? Or out of luck?
Phil

A: I replied: "Usually there’s a way to increase the setback but it often involves compromise. By compromise, I mean that you may need to change to a seatpost with more setback and you probably won’t find a seatpost with more setback that’s a nice as the seatpost you have.

You also might need to shim the seatpost to get it to fit in your frame. Here are Cane Creek's seatpost shims, for example.

With a really quick search I found an example of a seatpost with more setback just to show you, the Nitto Lugged seatpost, which has a 40mm setback (photo).

Yes, this is a very old-school seatpost, but if it proved a huge improvement, you would at least know what setback works best for you and you could go in quest of a seatpost that provides it.

I haven’t done an exhaustive search for seatposts with extra setback, but there should be a few others out there with any luck. You might also ask Lynskey if they’d make you one with the setback you need – though I don’t know if they make custom components like that. Some framebuilders might.

Another option, though it means switching saddles, is trying to find a seat that’s longer or has longer rails or rails that allow putting the seat in the right position to provide the additional setback you require. So, for example, if you found a saddle that was an inch longer in the back, that might solve the problem, assuming you could sit on that seat of course. An example is Fizik's Arione.

Since bicycle shops that specialize in fitting people often run into this issue, they can be a good resource for the seatposts and saddles like this. However, it would need to be a large shop that carries a good inventory and fits lots of people. (The photo shows an SR "super-setback" seatpost that was around in the 1980s, and which you might find today on eBay.com.)

Hope this is helpful and you find a good solution.

To which, Phil answered, "Thanks.  Hate to get rid of my Brooks saddle but that may be the best solution. That Nitto seatpost looks really weird.

Wonder if there is a way to adapt the front half of the seatpost platform to the narrow portion of the rails on the Brooks saddle. Don’t want to go much further as I worry about the stability of the saddle."

And, I wrote back: "Yes, definitely weird. I have never seen an adapter like what you describe, however, I think one could be made with a little ingenuity. Today it’s much easier to design things like that with 3D printing.

If I was doing it, I’d look for a machinist that has the technology and likes to solve problems and has worked on bicycle components. Machinists will usually discuss projects for free so you know what you’re going to have to spend up front.

I would think, though, that it wouldn’t be too difficult or too expensive a part to design and make."

And, Phil then said, "Yes. Plus, although I have never looked at rails on saddles very closely, I just don’t recall seeing a saddle with “straight” rails – i.e., that don’t curve inward as they culminate in the nose of the saddle."

Summing up, I replied, There have been all kinds of bizarre saddle shapes and designs going back to the dawn of cycling, Phil. But, the traditional road saddle has the narrow nose and the rails that follow its shape.

There's at least one reasonably new saddles that has an I-beam running down the middle that requires a seatpost of the same design - both made by SDG (if you look closely at the photo, you'll see there are no rails, instead an I-beam runs down the center of the saddle). On these you can move it forward and back more, so it might be worth a look.

Hope you find the fit you're looking for,
Jim
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Q: I'm sure you get this all the time, Jim, but today while volunteering at the Bellows Falls, Vermont bike project I came across a wheel I'd been looking for, a Weinmann 129A 27-inch rear wheel.

Even better, it was equipped with a SunTour Pro Compe 6-speed 14-34 freewheel, which is about perfect. By itself this made me happy.

But after clearing off the years of grime I found this little sticker which made it even more exciting. Any idea when you were using these stickers as I doubt you would remember when/who it was built for?!

Thanks for your time,
Christopher C. Purvis

A: Thanks for making my day, Christopher! In 1978 I left the famous Andy’s Cycle Shop in Keene, New Hampshire and went to work for West Hill Shop, now in Putney, Vermont. At that time Neil Quinn the owner (retired now) had opened a second store in Brattleboro, Vermont.

I was managing that shop and working sometimes in Putney, too. Later, we closed the shop in Brattleboro to focus on our busier Putney location. I missed the wonderful cheese danishes I used to have every morning from the bakery next door to the Brattleboro store.

That’s my long way of saying that I probably built that wheel you found in one of those stores – and it would have been before 1982 when I left for California where I’ve been ever since. [Bonus: if you're hankering to build some wheels, click on the vintage Raleigh photo for my bicycle wheelbuilding step-by-step.]

Unfortunately, while I had the good idea to have stickers made for my wheels, I was not smart enough to record my wheelbuilds in a notebook, or use serial numbers, so I can’t tell you who I built those for. And, I’m still using the same stickers on my wheels because I bought way more than I should have when I ordered them from the printer back then. So I'm still using them on new wheels I build.

It’s very nice of you to send me the photo of that long lost wheel. I hope it’s still reasonably true and rideable! Just for laughs, here’s one of my favorite photos of back then. In case you don't recognize it, I'm in my Tour-yellow Richard Sachs T-shirt, back at West Hill in Putney building a wheel on the classic Var Atomic jig.

Enjoy that vintage Jim Langley-built wheel!
Jim

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