Calculate bicycle spoke lengths the old way

This is an interesting math exercise that has been largely replaced (hidden, actually) by web-based spoke length calculators, linked to nice databases for hub dimensions and rim ERD values.  I always measure rim ERD for myself and measure at at least 2 different points around the rim.  And I always check the supplied hub dimensions for myself.  Sometimes a bad value is stored, so checking is worth the extra few minutes it will take.  Some hubs and rims are rare enough that they aren’t in the databases at all, so once you’ve determined the measurements, sending them to the various calculator sites is a nice way to pay it forward.  Good karma from that can’t hurt.  Remember, you are the one that will pay for replacing spokes that are not the correct length, so measure at least twice.  Personally, I consider the correct length to be where the top of the spoke is level with the bottom of the slot in the nipple.

A couple of web-based spoke length calculators are:

Prowheelbuilder

EDD

2/3/4 cross lacing:

The basic formula is:

L = sqrt(R^2 + H^2 + F^2 – 2RHcos(360/h*X)) – shd/2

Where:

L = calculated spoke length
R = rim radius to nipple seat (ERD/2)
H = hub radius to spoke holes (spoke hole circle diameter/2)
F = flange offset from hub centerline
X = cross pattern (2, 3, 4…)
h = number of holes in one side of the hub
shd = diameter of spoke hole in the hub

Check it out, it’s not really that complicated.  Most any calculator can handle this fairly easily.  When you’re done, try one of the online spoke length calculators to see what lengths they calculate.  You can try more than one spoke length calculator and average the results (they will likely have slightly different results, depending on any fudging done during the calculations).

Since spokes are generally available in 2mm increments and some in 1mm increments, you’ll likely need to round the calculated values.  For me, I tend to round to the closest available length, but you’ll have to determine that on your own.  Experience with calculated lengths on successful wheel builds will tell you which way to go with different length calculators.

Definitely a math geek’s exercise, but sometimes it’s nice to see how the “behind the curtain” work is actually done.

Radial lacing:

For radial lacing it’s much simpler.  it’s just a right triangle and you’re solving for the hypotenuse.  The formula is:

L = sqrt((R-H)^2 + F^2) – shd/2

Where:

L = calculated spoke length
R = rim radius to nipple seat (ERD/2)
H = hub radius to spoke holes (spoke hole circle diameter/2)
F = flange offset from hub centerline
shd = diameter of spoke hole in the hub

Be aware that there are multiple places in the formula for rounding, and length calculators can and do round differently.  This accounts for the differences between methods.  All of them should deliver results within a mm +/-.

And you thought you’d never use trigonometry once you finished school.

2nd Annual Bourbon and Tobacco Tour – April 13, 2019

To help us with planning, please click here to register.

Saturday, April 13:

We will meet at the east side of LBL on US-68/KY-80, just west of the bridge over Lake Barkley.  Parking is on the north side of the highway, and there is plenty of parking available.  I will have some repair/adjustment tools, grease, chain lube, floor pump, work stand, and some spare tubes and patches.  Hopefully no major repairs will be needed before, during, or after the ride but we’ll be prepared for the usual (and some of the unexpected).  We’ll leave from the parking area around 10am.

There is no cost for these rides.  If you want to chip in a little for the Saturday post-ride cookout, that would be appreciated, but it’s neither expected nor required.  There is a nice surprise planned for the midpoint of Saturday’s ride.

The route:

The route is entirely within the LBL.  This loop starts and ends at the east entrance to LBL, and is a little less than 40 miles, with about 4 miles of well-compacted gravel.  The gravel should be fine for 23mm tires, but I will ride this section next spring and will alter the route if it looks at all iffy.  As of now, there are a small number of actual turns in this route, 8 by my count, in the entire ride, so there should be no issues with navigation or getting lost.  I will give my cell number to riders, should assistance be needed during the ride.

 

 

Click to Download Cue Sheet

Moonshine:

If folks are interested, we’ll head over to Casey Jones Distillery near Hopkinsville to sample some genuine Kentucky moonshine.  We can take a tour, or just try some samples.  I need to know if y’all would like a tour so I can let them know, OK?

Post-ride cookout:

We are planning a cookout after the ride.  LBL does not allow alcohol, and the Barkley Lodge pavilion is reserved.  We’ll just have it at my house.  It’s easier anyway as I can just leave everything is the fridge/freezer at home and not have to haul it to the Lodge.  If you’re local, just bring something to share.

Sunday, April 14 – ride the trails:

If folks are interested, we’ll take some fatter-tired bikes out for some trail riding on Sunday.  There’s a lot to choose from, the map links below will give you an idea of the variety available to us.

We’ll figure out when and where to meet during the cookout and I’ll update the information here.  Most likely will be one of two places.  Either at the LBL North Visitor Center, or the LBL Golden Pond Visitor Center.

LBL Hike and Bike Trails

LBL Maps – click the Trails tab.

I didn’t know there were 500 miles of trails and 200 miles of roads in LBL. It is great to have this area so close to home.  Not all of the trails are available for bicycling, so check the website while you scout a potential route.

Temperatures to expect:

The average high temperature in April is 66 degrees, so good riding temps, but plan on 10-15 degrees plus or minus from that.

Lodging:

Here are some options for lodging and some suggestions for restaurants in the area.

Kenlake State Resort Park Reservations

Lake Barkley Lodge reservations

Both are reasonably priced and are just a few minutes from our starting place.  Kenlake and Lake Barkley both have restaurants too.  For those folks arriving Friday, I have a place in mind for dinner.

Bike Shop:

Bikes and Moore in Hopkinsville is a shop that I’ve been to several times, and I couldn’t find a complaint if I tried.  Good folks and they’ll be happy to help you out, should you need more than a tweak or two.

Questions:

Contact me if you have any questions, I’ll do my best to help.

Some sponsors have graciously agreed to help out.  I have no right to expect anything and I’m immensely grateful for their support.

Chain-L – the best chain lube available

 

 

 

PRIZES – Yes, we have prizes too.  They won’t take you out of the amateur ranks, if you’re concerned about that – but they are good ones that will definitely see some use.

Prize #1 – for the rider traveling the farthest to attend the ride.

Prize #2 – for the oldest participating rider.

Prize #3 – for the youngest participating rider.

Prize #4 – for the best C&V bike, as voted on by the participating riders.

Prize #5 – for the Lantern Rouge on Saturday’s ride.

Please watch your speed while driving in LBL, it’s federal land, so speeding tickets are expensive – as Agent K said “the rangers do not have a sense of humor they’re aware of.”

2019 rides – should be a fun summer

I’ve been looking at a calendar and conversing with some fellow C&V enthusiasts (inmates) about meeting up at some rides next spring, summer, and fall.

First, in April, will be the 2nd annual Bourbon and Tobacco Tour.  I’ve worked out a couple of different routes and we’ll decide which one to ride after seeing the road conditions next spring.  If folks are interested, we’ll ride trails on Sunday, making a full weekend of riding.

In May is Storming of Thunder Ridge in Lynchburg, Virginia, which is a very popular ride and a challenging century.  I’ve not done this ride before, but several other C&V personalities have.  Registered for this one.  I’m hoping to have the Masi ready for this ride.

July is the Ride Across Indiana (RAIN) that goes from Terre Haute to Richmond in a single day.  165 miles, mainly on US-40.  That will be my longest day on a bike by far.  Logistics are an issue when you ride from point A to point B instead of point A looping back to point A.  The ride organizers have provided several choices to help with this.

September is the Centenario Coppi, a C&V ride to celebrate the 100th birthday of Fausto Coppi, one of the legends of pro cycling.  A bike show is part of this weekend, so lots of bike porn to see and a C&V ride too.  What’s not to like?  Registered for this one.

October is the Hilly Hundred century, in and around Bloomington, IN.  Unusually, this ride is split into two days of riding over Saturday and Sunday.  All reports say this is a very well organized ride.

Also planning to ride with steelbikeguy for a donut at Tanner’s Orchard sometime in October.

This is a tentative set of rides.  Life happens, so changes are possible.

Wheel bearing replacement

I replaced the rear hub wheel bearings on the Merckx today.  Knocking the old bearings out was easy enough and I managed not to lose the spacer between the bearings.

The new bearings are in the freezer, ever so slightly reducing the outside diameter.  I warmed up the hub with a heat gun, the intent being to slightly increase the ID where the bearings sit.  Installed the bearings, using a socket that was slightly smaller in diameter than the bearing, but large enough to contact the outer race.  I even remembered to put the spacer in the hub before installing the second bearing.  Bearings are done and the slight play I noticed earlier is gone.

While the tires were off, I put the wheels in the truing stand and checked them out.  The rear wheel is good, but the front needed a tweak or two.  All nice and true now.

I replaced the 25mm Michelin Pro4 tires, as they measure 28mm on the Boyd rims.  There was very little clearance with these tires on the Merckx frame, so a single broken spoke would have probably rendered the bike unrideable.  The new tires went on easily and measure 24mm, so there is at least a reasonable amount of clearance.

The tires ride well, and the Merckx seems to have picked up the performance a notch or two.  Not bad for a few minutes of work.  Looking forward to the next longish ride.

Tanner’s C&V Ride in Chillicothe, IL

Went up to Chillicothe, IL for a ride out to Tanner’s Orchard for an apple cider doughnut.  You may reasonably question the sanity of driving 6 hours and then riding 20 miles for a doughnut, but sometimes you have to do what you have to do.

We got to Chillicothe around 9pm Friday night, checked into the hotel and went in search of food.  Had a pizza at Monical’s just before they closed, which tasted pretty good.  Fuel, you know, for tomorrow’s ride.

Met some nice guys riding classic steel bikes along the banks of the Illinois River in Chillicothe on a brisk Saturday morning, temperatures were in the low 50s.  I brought my Lemond Alpe d’Huez, with a tubular wheelset installed and it rode very nicely.  There’s not many miles on this bike after the restoration was finished, but it was like reconnecting with an old friend.  No introduction needed, no getting-to-know-you questions, just “what are we waiting for?  Let’s go.”

I enjoy the classic bikes more than the carbon wonder-bikes, because they have a air of elegance and quality about them that easily belies the number of miles or years they’ve been around.  They have experience.  Riding with C&V folks is fun too – I don’t think I’ve ever met a cyclist on a classic bike that didn’t end with “great bike, enjoy the ride.”

The doughnuts lived up to their billing, but it seemed colder when we left the orchard than when we got there.  Oh, well – we’ll warm up again soon enough.  We took a different route back to Chillicothe, and the descent down to the valley from the bluff was great fun – I got up to 37 mph on the descent.  Not a lot for some riders, but still fun.  Drivers were considerate, and we were only honked at once, which might be a record.

Many thanks to Steve (steelbikeguy on BF) for organizing this ride.  We’ll be back next year.

Pinarello Turismo

Wow.  This bike just moves.  A full 2 mph faster average than the Merckx carbon on several different rides.  I don’t know exactly what it is that makes it faster, but there’s no doubt about it.

I’ve gone through the entire bike, cleaning, re-greasing, and adjusting it as well as I’m able.  I just rode it on a 62 mile ride in Paducah, Kentucky and there were no problems – aside from needing a better engine, but that’s a topic for a different discussion.

Fitwise, the stem is shorter than I would normally use, but I won’t change it out because I don’t want to lose the Pinarello panto’d on the stem.  Maybe not the best choice but I’ll adapt.

The 35 year old Campagnolo Gran Sport group rides and shifts very well.  The brakes are noisy, which isn’t a big surprise with old pads.  The braking isn’t horrible, but I’ve ordered some new pads that should improve braking and stop the squealing.

Later this year, I’m planning to strip the parts from the frame and fork, and have them painted blue, Pinarello blue to be specific.  The bike has already been partially repainted, so there’s no concern with destroying original paint.  I’ll replace the decals too, and the bike will look like new.

But it will continue to rack up the miles.  It’s too much fun to ride to let it waste away as a display bike.  Bikes are made to be ridden first, and admired as examples of fine craftsmanship second.  At least that’s my take on it.

Misaligned Minds ride in Paducah, Kentucky

We chose to do the metric century, called that because it’s 100 kilometers in length, about 62 miles.  Rolling hills, nothing too serious.  The start point, at Bob Noble Park in Paducah, is about an hour from my house, so we had a little drive to get there.  Picking up our registration packet was simple enough, and then we got the bikes ready to go.  Aired up the tires, checked to be sure we had what we needed, and headed out.

I left my phone at home (grrr) but it turns out you don’t actually need a phone to ride.  It would have been nice to get some photos during the ride, but oh well – we came to ride.

The riders in my group are from the midwest – Evansville (Rob), Florence (John), Cadiz (me), and Memphis (Bob).  We all rode bikes that are 20+ years old, in the cycling vernacular they are Classic and Vintage (C&V), just like their riders.  The carbon, plastic, go-fast bikes are certainly capable but we all enjoy the fun of maintaining and riding older bikes.  They have a charm and quality that we all find enjoyable – and spending the day riding a classic steel bike is fun.

The rest stops were very well done.  Ice cold water and Gatorade, good selection of snacks, and really nice folks manning the stops.  Every one of the four rest stops was as good as the previous one, something that has not always been true at other rides.  The route marking was good but there were some old marks that were plainly visible and that caused two of our group to follow a previous route.  We met up with them later.  Drivers were courteous too, most of them moving completely into the far lane when passing us.  We rode side by side, but moved into a single file when we saw a car approaching.

The SAG vehicles (Support And Gear) were out and about, and even brought us a bottle of water when we were between stops.  It was warm out and that was appreciated.

While cresting hills, drivers waited behind us and passed after they could see the oncoming lane was clear – and this happened several times.  A sincere thank you to the drivers for their courtesy today.  No one that passed us seemed irritated that we may have delayed them a few seconds, no angry car horns, no drivers yelling, just a nice ride on a Saturday.  It really doesn’t get much better than that.

Chain Reaction Cycling Club in Paducah, Kentucky puts this ride together, and to my mind, this was the way a ride should be done.  From the smiles at the end of the ride, they were more than successful.  We’ll definitely be back next year.

A little fine-tuning

The first longish ride on the Merckx is finished, and I have a little work to do.  First, the rear caliper was twisting a little, and pushing the left pad against the brake track.  I don’t really need any help slowing down when I’m trying to go forward so that needs to be addressed.  Second, the rear wheel seemed to have a little bearing play that shouldn’t be there so that needs to be investigated.

I tightened up the recessed nut for the rear caliper and it’s better, but the real problem might be that the housing is a little too long and is pushing the caliper.  I’m going to ride it as-is and see how it goes on the next ride.  If it’s not working properly, I’ll shorten the housing.

The wheels have cartridge bearings, so there isn’t much to adjust compared to cup and cone bearings.  The caps that hold the bearings in place were not completely tight, so I snugged them up and reinstalled the wheel.  There is no bearing play now.  I checked the shifting and it’s good.

I ride a fairly small frame, so there isn’t a lot of exposed seatpost.  I had mounted a red blinky light on the seatstay of the CAAD8, but on this frame the seatstays are shaped, not round so the mount doesn’t work so well.  I have a nice rubber mount for the light that wraps around the seatpost, but then I can’t fasten the seatbag in place.  So I ordered a top tube bag that sits on top of the top tube and fastens around the tube and the stem.  You can easily get at the items in it while riding, and it isn’t in the way.  Hopefully this will turn out to be a good solution to the blinky light vs seatbag war.

I’ll know in a couple of days.

2018 Bourbon and Tobacco Tour – in the historical documents

The weather for Saturday’s ride was basically perfect.  Temperatures topped out in the low 70s, with light winds.  The winds out of the east picked up later in the day, which didn’t help as the final few miles had a long climb, into the wind.

This ride kicked my butt.  The time I’ve spent behind my desk working didn’t actually contribute to my riding fitness.  Hmmm.  A 55 mile ride in (relatively) flat Illinois is much easier than a 55 mile ride in the Kentucky hills.  Clearly I have some work to do.

It was great to meet some BikeForums members in the flesh and on the bike, and the cookout afterwards was fun as well.

Some things to take away from the ride:

1. My 1989 Cannondale ST600 performed very well, no issues at all – not bad for a 29 year old bike.

2. The Compass tires were everything they were advertised to be, a nice smooth ride and good traction.  I ran 60F/65R tire pressures.

3. The Selle Anatomica saddle is very comfortable (for me).

4. I need to be in better shape.  I have a shape, the problem is that it’s rounder than it should be.

5. Drafting behind Adam and Jamie would have been a smart choice.

6. Ex-Pres and PilotFishBob are very patient riding companions.

7. Apparently everyone that owns a boat was pulling it on a trailer today, but with a single exception, we were given plenty of room while we were being passed.  We were riding single-file for the most part, and moved to single-file when we saw a vehicle approaching from the rear.

Will definitely do this again next year, and since the new bridge across Lake Barkley should be finished by then, the route will be different than this year’s route.  Might even go south into Tennessee and back.

Thanks again to the kind and generous sponsors that provided prizes for our ride – Road ID and Chain-L chain lube.

Finishing up the ST600

The shim I cut to use the 25.4 handlebars with a 26mm stem wasn’t holding very well, so I picked up a replacement stem with a 25.4mm clamp.  A Nitto Technomic stem, 150mm tall – great fit and finish, and it’s installed.  The bars are on and the brake levers are reinstalled and positioned as best I can without riding it.

Got out for a short ride, and the stem/handlebar/lever positions are good.  Now the mechanicals are finished.

I wrapped the handlebars and finished the ends, but I think the right side ended a little too close to the stem.  I have a GUB gps mount that fits on that side of the bars, so I might redo the end.  Removing a half inch would give better clearance for the front brake cable.

Barring that change, or even including it if you’re generous, the ST600 is finally ready for the road.