3 piece crankset on cruiser frame???

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I'm looking at using a 3 piece crank set on the Workman INB frame, mainly cause I obtained a really nice Profile Imperial 44t sprocket for peanuts (and it's what was used on the Core 77 build that inspired the initial project). Hopefully "Bicycle808" is reading, apparently done some updating stuff to these INB frames!
Now the problem is the sprocket won't fit a one piece crank set (at least none that I have on hand) and hopefully I don't have to go with a Profile crank set up based on the pricing I've seen...

I don't know squat about BMX bikes, which most three piece crank sets I'm seeing are referred to. What are the items of concern when going this route (1 to 3 crank conversion)? Obviously BB size is an issue but typically the only measurement I seem to be seeing is the crank arm length. I get that some of the spindles are square taper or splined for the crank arms, again though, no size references beyond the crank arm?

I browsed the "How To" section but didn't find anything specific and I' know it's been done quite a bit. Hopefully somebody can shed a little light on this conversion, again this is going on a Workman frame but I think my confusion would translate to other 26" cruiser frames... Thanks in advance for any tips/ help!
 
marked, similar project upcoming for me.

Also, they sell adapters to swap 3pc sprockets to 1pc, or vice versa, forget which way it goes..
 
If it's a 3 piece bmx crankarms your using with profile imperial, then just use an american bmx sealed bb and the spindle that comes with the arms. Remove the oem cups from the frame and just press in the new sealed bearing. That is if you want to use sealed bearing. They also make an open ball bearing bmx bottom bracket from poverty.


Link to the bb i used. Except it was an american instead of mid.
http://www.danscomp.com/products-PARTS/456049/Mission_BB_Kit.html

The setup installed on my '47 western flyer with no modification.
 
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If you wanna run a Profile Imperial, I'd STRONGLY advise against going with a euro adaptor; you won't need it. Depending on the vintage, your Imperial will either have a 7/8" bore or a 19mm bore. In either case, you'll want to get an American BB set for 19mm cranks (You can spring for a Profile or Redline makes a good one for cheap... at any rate, don't cheap out! Definitely get a sealed one) and any BMX-style 3 piece crank with a 19mm spindle. If the Imperial has a 7/8" bore, you'll need a 7/8"-to-19mm hat spacer, which likely came with your sprocket. If not, Profile sells them, or go with Option E from Porkchop **EDIT** porkchop doesn't have this part; if you need to run a 7/8" bore chainwheel on a 19mm spindle, get the part from Profile! http://www.profileracing.com/estore/product.php?productId=223 **EDiT OVER** **EDIT**April 2017 the url for the 7/8" to 19mm hat spacers is now http://www.profileracing.com/product/sprocket-adapter-spacer/ **EDiT OVER** You'll want to measure carefully before you line everything up, as frequent rebuilding of most BMX cranks leads to the splines wearing down on the spindle.

FWIW, a sprocket like the Imperial is not meant for square taper cranks, and won't work on any.

So, which crank? Any 19mm spindle will do; 19mm is basically the "standard" bmx 3 piece these days, although there are 20.0mm, 22.0mm, and 7/8" spindles out there, too. I'm running a Profile Flywheel 44t on a 19mm Redline Flite crank.... on a Worksman INB.

Any other tech questions or if you need links, feel free to ask. Oh, and Baldwooky, you can get 15/16" (aka 23.8mm) to 19mm hat spacers, to run a 1piece type sprocket on a 19mm 3 piece.... but the only way to run a 3piece sprocket on a OPC is to bore out the hole to 15/16", and if you can't do it perfectly, don't bother trying.... You'll have tight/loose spots in your chain forevermore.
 
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PS- I just rode home from work, and while I was riding, I felt bad about my post, b/c I feel like stuff got left out. Really, I was worrying about the tube spacer. I kept thinking "RRB ppl are not prepared to deal with a tube spacer!" So, I'll provide a link to some very thorough instructions:
http://www.danscomp.com/serve/faq/cranks_faqs.htm
Click on the link for "3 piece with American Bottom Bracket", and it'll take you to a pdf file that will walk you through it. Just remember: you need an American BB for 19mm spindle, and a 3 piece crank with a 19mm spindle. Run whatever you like on your bike, but i'm loving the 180s I got on my Worksman INB...
 
Ah, "Bicycle808" comes in with the answers! No offense to everybody else, just that I knew from another thread he'd messed with a Workman frame and several of the items I'm tossing around... Thanks none the less for the information everybody!:thumbsup:

What I'm playing with here, for additional info, looks to be a 7/8" bore, 44 t, all I have is the sprocket, saw the pin hole and just assumed that I could use it on a one piece crank set:crazy: if I decided to go that route... Nope!
So from what I gather here then, after confirming measurements on the frame, I'll be needing:
- BB, American... which should cover the INB frame?
- 19mm spindle, with a 22mm adapter hat since I want to use my Profile sprocket
- Stay away from square taper spindles if I plan on using my Profile Imperial sprocket... which I plan to use, it polished up too nice not to!
- Lose my current bearing cups to facilitate sealed bearing set up... American!
- Follow the PDF on Danscomp (already save the PDF!)

Here's a little cool info some of you BMX fans will dig... I just discovered that Profile Racing is like two/three miles away, who knew???

Thanks again everybody... ....., I hope I don't start getting into BMX bikes now!;)
 
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I'm glad I was able to help.... a few clarifying points:
-Your sprocket was designed for the Profile SS crank, which has a 7/8" (22.2mm) spindle. I messed up with the hat spacer I recommended.... you'll actually need to get the part from PRofile, as a 22.0 will fit loose. You want to pick "A" from the link here: http://www.profileracing.com/estore/product.php?productId=223-

-I used this BB. If you look, you'll see it has the tube spacer, the bearings, the American cups, the cone-shaped washers, and like 5 million spacers. You'll need to use a few spacers, but not nearly all of them. The spacers are used to make sure the cranks are tight, and to dial-in the chainline. Be sure to get it right before you really tighten it down.
http://www.niagaracycle.com/categories/redline-bb-set-for-3-piece-cranks-19mm-american

-Yes, the American cups will fit the inb frame.

-Depending on what crank you get, it'll probably have the arms, the spindle, the bolts for the spindle, and the other bolt that goes in the drive-pin hole of the sprocket to keep it tight to the crankarm. The spindle will be round, and have between like 6 and 4000 splines.

-If you run BMX bars, you're done... You'll keep wanting to build BMX-type bikes. A 3 piece BMX crank on the other hand, will possibly put you off the BMX builds. It's not actually hard, but it's more involved than any other cranks I've ever installed..

HTH,
Rob
Ah, "Bicycle808" comes in with the answers! No offense to everybody else, just that I knew from another thread he'd messed with a Workman frame and several of the items I'm tossing around... Thanks none the less for the information everybody!:thumbsup:

What I'm playing with here, for additional info, looks to be a 7/8" bore, 44 t, all I have is the sprocket, saw the pin hole and just assumed that I could use it on a one piece crank set:crazy: if I decided to go that route... Nope!
So from what I gather here then, after confirming measurements on the frame, I'll be needing:
- BB, American... which should cover the INB frame?
- 19mm spindle, with a 22mm adapter hat since I want to use my Profile sprocket
- Stay away from square taper spindles if I plan on using my Profile Imperial sprocket... which I plan to use, it polished up too nice not to!
- Lose my current bearing cups to facilitate sealed bearing set up... American!
- Follow the PDF on Danscomp (already save the PDF!)

Here's a little cool info some of you BMX fans will dig... I just discovered that Profile Racing is like two/three miles away, who knew???

Thanks again everybody... ....., I hope I don't start getting into BMX bikes now!;)
 
I am a 3 piece guy, bent and broken 1 piece cranks left me walking to many times!
You don't have to go Profile expensive, a set of generic 3 piece are plenty strong. I have used D.B., GT, SINZ, and Mongoose with great success.
Also, I live close to Profile, working in a cnc shop I met 2 guys that had quit working for them, due to quality and company wide drug use. Neither seemed disgruntled, just time to move on....
I try to use standard thread spindles, that way I can get $15.00 sesled b.b. from Dans bmx.
 
Rob "Bicycle808", "A 3 piece BMX crank on the other hand, will possibly put you off the BMX builds. It's not actually hard, but it's more involved than any other cranks I've ever installed..."
Oh it's not really a complexity issue in as much as it is just so many freak'n sizes, I was just getting comfortable dealing with one piece cruiser style cranks and BB's! I've swapped out the Shimano MTB BB's no probs, just get the size that was in it, it's when you start changing stuff from the OEM sizes that tards me all up, like going three chain ring to single and then doing a different spindle length:crazy:
"Mikeeebikey", when you say "standard thread" you mean 24 tpi, right?

I do have one more question, in reference to the sealed BB's I'm seeing "American", "Mid", and "American Mid", just curious what's the diff? I'm gonna go with the Redline from Niagara that Rob posted the link for, dealt with them before with no probs.
 
American is the fat, 51.3mm shell that your Worksman and most every bike that takes a 1piece has. If you buy an American-sized BB for a 3piece, you get cups to fit into the frame's BB shell, and then the bearings that fit into those cups. "Mid" shells are smaller, and basically the exact same bearings press directly into the frame's bb shell---no cups. Basically, a Mid BB shell matches an American shell with cups installed. So, of course, a bb set labeled American/Mid will work in either shell.... you just leave the cups out of the mix if you're running a Mid-shell frame.

As for the complexity, the thing that makes a 3piece BMX crank install tricky is that you have a bunch of spacers, some of which you won't use, and it may take a while to get chainline dialed in properly. The up-side of this is that you can adjust chainline very easily, so there's always that.

Profile got their start up here in Jersey, when they made auto parts. They moved down to Florida before I was born, and before they got into BMX stuff. I think Profile is going thru some of the stereotypical "3rd generation" problems that plague family-run businesses. The founder cared, and his kid cared, but the grandkid seems kind of "over it". Profile was once known for top-notch quality, but now that have some issued with tolerances being kept tight enough and stuff. Mikeeeeybikey is quite right, though: you will do fine with a more modestly priced crankset.... just look for the 19mm spindle. The number of splines on the spindle won't matter; any 19mm will fit once you install the hat spacer.
 
Pics of a Worksman INB, outfitted with a 3 piece:
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Up at the train station...
232323232%7Ffp83232%3Euqcshlukaxroqdfv%3A395%3Dot%3E7%3B9%3C%3D824%3D34%3A%3DXROQDF%3E286487%3B%3C5%3C259ot1lsi

Profile SS Flywheel Sprocket has a 7/8" bore; came with the 7/8-to-19mm hat in the bag from Profile... Mounted up to Redline Flight cranks, 180mm long....
232323232%7Ffp83232%3Euqcshlukaxroqdfv6%3C67%3Dot%3E7%3B9%3C%3D824%3D34%3A%3DXROQDF%3E2864872%3C43259ot1lsi

I used the same Redline 19mm American BB set from Niagaracycle.com that I'd linked above....
232323232%7Ffp83232%3Euqcshlukaxroqdfv4755%3Dot%3E7%3B9%3C%3D824%3D34%3A%3DXROQDF%3E2864872%3C44259ot1lsi

Another view. Dang, that's dirty! Excuse the dust; I've been trail-doggin' this bike all summer...
List of parts used for the crank install:
http://www.niagaracycle.com/categories/redline-bb-set-for-3-piece-cranks-19mm-american Redline BB set
http://www.planetbmx.com/shop/bike-...ne-flight-cranks-chrome-with-american-bb.html
Redline Flight crankset
http://www.profileracing.com/estore/product.php?productId=7
PRofile Racing SS Flywheel sprocket (I got high-polished, 44t...)

232323232%7Ffp83232%3Euqcshlukaxroqdfv%3A%3B7%3Enu%3D8%3A%3A%3B%3E733%3E259%3EWSNRCG%3D377396%3C%3B6934%3Anu0mrj

A fun bike; got a lot of US-made goodies, like the King BMX-size 1" 2-nut Headset, Profile Wedge Stem (XXL), AME grips and S&M Cruiser Slam bars....
232323232%7Ffp83232%3Euqcshlukaxroqdfv9%3B86%3Dot%3E7%3B9%3C%3D824%3D34%3A%3DXROQDF%3E2864872%3C45259ot1lsi

Plus it's got a wreck-diesel 1" threaded Landing Gear fork with drum brakes front....
232323232%7Ffp83232%3Euqcshlukaxroqdfv386%3A%3Dot%3E7%3B9%3C%3D824%3D34%3A%3DXROQDF%3E2864872%3C46259ot1lsi

....and rear.
232323232%7Ffp83232%3Euqcshlukaxroqdfv%3B%3C6%3B%3Dot%3E7%3B9%3C%3D824%3D34%3A%3DXROQDF%3E286487579%3A259ot1lsi

Put some Crimson Ghost/ Misfits donuts on to maximize the freak-factor....

Can't wait to see Mike G's INB, once he's got it all sorted....

Regards,
Rob
 
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OK, well that portion is set in green (cash that is)...
Just bought a set of Redline Monster cranks, 175mm
ordered that redline BB from Niagara Cycle the other day. Gonna take a jaunt over to Profile and see if I can't buy the adapter direct... maybe see if I can't score some blem items and weasel some swag while I'm there, I'm guessing I'll probably be the oldest person in the building, should count for something!

Rob, I decided to go with the WM fork that came with the frame... so they're being blasted this week and then off to the powder coat, leaning toward a real dark blue metallic. Besides I already have a BMX style stem that's 1" quill style.

Now if only I could decide on wheel and hub combo:banghead:... Looking at a Weimann black rim set with a Nexus 3 speed... Bruiser Black and Blue!

Thanks for all the helpful info folks:thumbsup:, pics will be in the Build section in the coming weeks:cool2:
 
OK, well that portion is set in green (cash that is)...
Just bought a set of Redline Monster cranks, 175mm
ordered that redline BB from Niagara Cycle the other day. Gonna take a jaunt over to Profile and see if I can't buy the adapter direct... maybe see if I can't score some blem items and weasel some swag while I'm there, I'm guessing I'll probably be the oldest person in the building, should count for something!

Rob, I decided to go with the WM fork that came with the frame... so they're being blasted this week and then off to the powder coat, leaning toward a real dark blue metallic. Besides I already have a BMX style stem that's 1" quill style.

Now if only I could decide on wheel and hub combo:banghead:... Looking at a Weimann black rim set with a Nexus 3 speed... Bruiser Black and Blue!

Thanks for all the helpful info folks:thumbsup:, pics will be in the Build section in the coming weeks:cool2:
Looking forward to seeing it come together!

Luke.
 
I have some cruisers.Myself,I like the one piece cranks,but I am an old guy who like things simple..
Most of my cruisers run OPCs too.... but if you have an Imperial sprocket that you're just itching to run....

Plus, I can't deny that a quality 3 piece looks rad, and the stiffness is much improved.
 

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