You did such a great job explaining different BCD's, you need a part 2: Bottom Bracket standards. I am sure many people would be interested in how you determine what BB you need when building up your project bikes.
"Standard!!!" there is no standard when bikes are concerned!!! I've never known an industry to have SO MANY standards doing the same thing!!! At least they can agree that a bike has two wheels!! ;-)
this is a example.. if the UCI (Union Cycliste Internationale) banned your bike in a competition under them it means your bike is not standard for their qualification. One of the best example of that is the Old Faithful bike of Graeme Obree. So Yes there are still what we call standard for bikes that someone to follow. it depends on what are you on a bike thing like competitive or just casual
Hello Sir, iam a Bike Mechanic from Austria- just a Tip on Measuring the BCD on 5 Bolt Cranks: Measure from middle of 1st Bolt (hole) to the middle of the 2nd Bolt (hole) next to it and multiply by the Factor 1,7= BCD. Love your Videos- keep it up!
Aside from BCD measurements, there is also symmetrical and asymmetrical chain rings that needs to be taken into consideration. Best way to measure BCD is to take a measurement from the crank bolt center to one of the chain ring bolt center then multiply by 2.
I like this! But guessing at the exact center of the holes is not accurate, and with this method you double your mistake. Good enough for the more common sizes though I reckon. But if you have an uncommon size that’s close to a common size you’ll wind up ordering an incompatible part.
Yes, you must round your BCD measurements to the nearest common sizes on the market. For the uncommon BCD sizes you must do what Old Shovel have done, a little drilling is needed.
I love educational videos, I hope you add more "geeking out" vids to your repertoire. I'd love a detailed look at wheel building or selecting/indexing/adjusting derailleurs or matching derailleurs with the shifter/selectors etc. Basically, all the "geeky" things. I want to learn about it all and you've got a great teaching style/method.
Wolf Tooth has a BCD paper template you can print out to match up chain rings and cranksets. I use it all the time. My biggest challenge is finding shorter 165-170mm cranksets that I prefer over 175mm lengths which were more standard back in the day.
At 11:15 you re talking of that cool antique crank sets but when you grow in age you will find that the non binded rods are giving a narrow distance between the feet and this hursts your old bone joints, then you will love the newer ones.
Great video as always. I recently converted my old 90s Stumpjumper to 1x11, and with a clutched derailleur, and a 94bcd 42t chainring (not nw), have only had the chain come off once in 3 months. Was an experiment while waiting on a 94bcd nw ring, but works better than expected.
I find the most difficult part is finding cranks that have removeable chainrings. The chainrings are available online but the cranks can be expensive. Since I usually work with lower end bikes the crank/chainrings are usually welded. I've actually bought bikes just so I can salvage a good chainring. Sheldon Brown shows how to measure BCD using adjacent bolt holes but I'm sure you know about that. Good video.
The chain line should be mentioned as well. I tried a 1X setup on my oldschool xc mtb. 44T front to 11-50 rear. I noticed that I don't need that 44/11, so I swapped for a 38/11-50 and a perfect chain line. Since you have the most torque on the low gear, you want want to see your chain in a straight line there. On my commuting bike I'm running a 1X 42T/11-46. It's an oval chainring made by Garbaruk. You wouldn't believe it, but the oval chainring makes climbing feel so much easier. Perhaps you want to consider that for a future build.
You didn’t explain why you put the chainring on the back of the crank - I know it’s to get the centreline of the chain in the correct place - but some viewers may not know that the 1x chainring has to line up with the centre of the cassette. One may need thin spacers on the bb to get it right. On square taper bb’s spindle length is also important for chain line.
You should try to have a episode of restoration Rear Derailers and discuss on What would be good one for re and what not good to restore. Also that discussion on which Derailers front and back derailers for which bike would work best. Also that have different episodes on which year of older bikes are capable of having upgraded updated parts.
Great. 42T should be perfect. I have a couple of bikes with 42 in the front and they don’t spin out until about 30 mph. That SHOULD be plenty. With a 50 in the back, you can likely still pull a truck uphill, albeit very slowly.
love your videos. I just did some math and I think you can measure BCD on a five-arm spider by measuring the distance between two adjacent bolt holes and multiplying by 2(sin54)/(sin72) which is around 1.7.
Good decision: with a 11-51 cassette even with a 42 chainring you'll have plenty of low gear to climb steep hills, but you'll appreciate the taller gear for high speed!
BCD is a familiar concept to anyone who's ever shopped for wheels to fit an automobile. How many holes, how far from the center of the hub. It's easy to get very close on a five-hole ring or spider by simply finding a circular object around your house or shop that lines up to the center of the holes then measuring the diameter of that object. Jars, bowls, etc. are often good candidates for this.
Single 5x94 BCD narrow-wide chainrings may be ordered on commission from Garbaruk. They certainly deliver in mainland Europe, although I am not sure whether they distribute to the US.
Please just go even biggen on the streetfighter, I have a new cannondale tesoro on 40c tires and I run 11-28 10s cassette xtr group with a 46t chainring and it Gers me everywhere. But i agree 40t of 42 would be better but you can go bigger at the front
If you need to measure a 5-bolt crank or chainring, you can measure between one hole on one side, and either of the two opposite holes, then divide by 0.95 to get an accurate-enough result. For example, if you measure 123.5mm between opposite holes, then 123.5mm/0.95 = 130mm.
I found a KHS flite for 80 bucks I'm about to buy, guy says needs shifting tinkering, I bet it's a loose cable, in good shape, it's silver I'm not sure the year, the rear triangles are kinda swept on top, I need to get me a bike stand and tool kit, I miss working at the bike shop.
Also your wheel size matters when you choose your chainring. It is different for an oldschool 26” or something like 700c or 29”. I found that the hard way😂
I like getting bike nerdy. Please do more of these as a filler between builds. Is the 94mm BCD STX really common? I had a bizarre STX ('94 I believe) where the small cog was a carrier for all of the others... I ended up finding a vintage 110mm XT to keep the look. The only problem is the 75mm crank length which is way too long for most people by modern standards.
Paul, thanks for the feedback. And yes, back in the 90’s the 94 bcd, “compact” crankset was quite common and so there are a lot out there. Now though, since it is an old standard, there are few 1x chain ring options out there. The Wolf Tooth chainring I showed Is about the only one regularly available. There are some boutiques shops that make some but they are typically done in small batches and are hard to get.
That sounds like a 90’s Shimano Alivio crankset. The bcd is much smaller and the rings are pressed with one set of bolts to the spider. I’ve also struggled to find a 94bcd 5 hole narrow wide chain ring for a Stx 90’s crankset. I had to source a Shimano 300lx crank 5 arm/spider with a 110bcd chainring.
I want a crankset, i guess 3 piece, 110 bcd, with 200mm arms, a chainring protector, and 44t + 36t chainrings. Can anyone tell me where i can find such a crankset without spending $500?
I'm looking for advice on frame touch up. . .what kind of primer would you use on a steel frame? I am fixing up an '86 trek road bike. . .I have the naval jelly to eliminate the rust. . .any tips would be welcome
I've just installed a Eagle NX 12 speed on my own street fighter project. I can't seem to get the gears indexed properly. I'm using a 46 tooth chainring. I was was wondering if it was to big for the rear derailleur?
Can 144bcd work on a mtb bike or are the arms too long that they will come into contact with the frame? I was also thinking about trying a newer spindle crank on my 90s frame but I was worried about the chain line being too wide. Will it work?
Good question. I think it is a good possibility that the arms or the larger chainrings that would fit on a 144 bcd chainring would start to touch the chainstay on a mountain bike but I would guess it would depend on the bike. It could be corrected a bit using a larger/longer spindle bottom bracket to move the cranks further out but that would also affect the chain line. Good question though. Thanks for commenting.
Also, I have a question- what shock did you use on that old Specialized enduro? I'm building one of those right now and trying to figure out what to use for the rear shock.
Thanks a lot for the video! The only information I missed here is: do I need to make the chain longer? There are a lot of chain length calculators to check this, and it seems that your rear derailleur is in a weak position when driving 42/52. Is it really so, or +4 tooth is not so critical? I am looking for opportunity to change front 46 tooth to 50 tooth on my Cannondale Topstone, but I am using three chains and it's not so cool to change them all =)
I wish there was. I have not been able to find any other inexpensive options. There are a few boutique shops that make some in small batches but they are also expensive.
Hoi hier jan uit Nederland. I ready like tour video's. There are companies in our country that dril and make or produce the right chainrings. Every bcd every thoot ect..
You didn't mention whether you were using a rear derailleur with a clutch or not? That is the other piece of using a 1x system with such a large cassette. Perhaps because it wasn't adjusted, but your photo at the end where you were shifting the bike sounded awful, hopefully it simply needs some adjustment and a rear derailleur that has a clutch??
Your right, it does have a clutch. With the shifting I was more checking if the cassette and derailleur would work ok with the 42t front chain ring and the 51t rear cog without over extending the derailleur cage so I was shifting multiple gears at a time. It was a bit loud though.
Noted 😁 I try my best to make good content. I do have a bit of a silly side that often does not show in my videos. It’s always hard to know what will work and what will not but I do appreciate feedback.
