Building my first Klunker!

tatobomb · Apr 23, 2024

Hey all,

Ive wanted to do this for a while now. Let the fun begin! I got an old cruiser because it looked like the frames the guys in Norcal first started with.

Hopes and Dreams - sophisticated Rat

Stabilize Paint
Remove and store all parts but frame
New mtb bottom bracket, 2 piece crank all brushed aluminum (or just scraped off black
5 or 6 or 7 speed cassette. Is that possible?
Or maybe i just go old style free hub? 3-speed shimano?
Figure out how to put a modern headset on. Any references to earlier forums that can guide me?
Make it a mullet with 27.5 in back and 29 in front
Adapt motocross bars to give it a swept back look in cockpit
old-style brushed aluminum mtb wheels - places to look?
Ride like Hell!

user 3630 · Apr 24, 2024

Cool project for sure!

I might be able to offer a little beginner guidance to help you get started. First off, some of a shortcut might be to find a cheap mid eighties-nineties MTB for a lot of the parts you're looking for. You could conceivably get the brushed wheels, freewheel, crankset, BB, derailleur, shifters, etc from the right bike.

As far as doing a 2-piece crankset vs. 3-piece crankset, you're going to get a better chain line with the 3-piece, which is necessary for reliable shifting/gear changes. You're dealing with fairly spindly old steel frames with lots of flex, so there's not a ton of advantage of going 2-piece. Choosing between IGH and a derailleur system, it's your call, but the derailleur system is, to me, more versatile.

Regarding headsets, it's been a while, so I can't point in a great direction, but there's some voodoo that can be done of testing part compatibility between the different standards, although there's likely already a thread on some forum that explains all that. I searched briefly, but was not able to quickly find something. Apparently you can buy something like this as well.

You probably already know this, but at minimum you'll need a BB adapter like this, and a derailleur hanger adapter similar to this.

Lastly, I'm not sure there's much advantage to using a larger wheel upfront, and it also might not fit. If you want something other than 26", you'll probably need to build them yourself (not a big deal if you have experience with it), but it can get spendy if you have to pay someone else. If you do the custom route, there are great ways to build out some cool stuff.

Hopefully this helps a bit. Cheers!

- LG

Captain Awesome · Apr 24, 2024

tatobomb said:
Hey all,

Ive wanted to do this for a while now. Let the fun begin! I got an old cruiser because it looked like the frames the guys in Norcal first started with.

Hopes and Dreams - sophisticated Rat

Stabilize Paint

Remove and store all parts but frame

New mtb bottom bracket, 2 piece crank all brushed aluminum (or just scraped off black

5 or 6 or 7 speed cassette. Is that possible?

Or maybe i just go old style free hub? 3-speed shimano?

Figure out how to put a modern headset on. Any references to earlier forums that can guide me?

Make it a mullet with 27.5 in back and 29 in front

Adapt motocross bars to give it a swept back look in cockpit

old-style brushed aluminum mtb wheels - places to look?

Ride like heck!

When you say “modern headset” do you mean threadless?

You’ve got a couple of options there depending on what the inside diameter of your head tube is. If it’s standard like Schwinn sizing then you can go with a retro ryder but if you have something else, then you can have a custom made one.

JA331 · Apr 24, 2024

This ‘62 Typhoon is a mix of 80’s and 90’s mtb parts as well as some bmx goodies.

The brake levers, 7 speed cluster, derailleur and shifter were pulled from barely used inexpensive mountain bikes. The wheels are a custom set but I originally had the mtb wheels fitted and it didn’t ride much different.

I combined the 7 speed cluster with a new Sturmey Archer drum hub. I kept the original front sprocket and added a set of 3 piece Redline flight cranks and sealed bottom bracket. As Speed2XS wrote you will end up with a much better chain line with this style of crank over a 1 piece.

The headset is a sealed Tange MX-125 which will fit almost every vintage American balloon tire bike frame and any threaded fork with 1” OD.

I have several klunker style bikes with Nexus IGH hubs. This one is superior to ride with a more solid feeling drivetrain and much less drag.

With the original mountain bike wheels.

JA331 · Apr 24, 2024

I built this bike for a RRB build off last year.

It is also a mix of parts from several cheap mountain bikes. It has a 3 x 1 drivetrain using a front derailleur and mtb cranks with 3 chain rings. It worked well but it was a pain and slow to select gears and I am now rebuilding it with a 2 speed kick back hub, original skip tooth chain wheel and 3 piece cranks. I tried using several 1 piece cranks and couldn’t get a decent chain line.

-1936 Schwinn frame
-Giant Rincon cro mo fork and Tange MX-2 headset
-Araya alloy rims
-Sakae mtb cranks and VP bear trap pedals
-YST sealed bottom bracket kit for Japanese JIS square taper 3 piece cranks
-Shimano front derailleur and shifter
-ACS freewheel and SA drum hub
-Dia-compe cantilever front brakes and levers
-Electra attitude handlebar
-Truetorch layback alloy post and Suntour quick release binder bolt

It was a heap of fun to ride, fast and as light as my alloy SE fast ripper but the gears were a pain to shift.

YST bottom bracket kit

Wildcat · Apr 24, 2024

A Monark is a good start for a klunker. Does it have a nameplate under the cranks?

As for a new headset, are you going to use the existing fork, or have another one in mind? A standard headset will probably fit the bike as is.

I would agree with the other posters and go with a 3 piece crankset using a BB adapter. I used one on my 42 Hawthorne, and it worked much better than a one piece setup.

I would also recommend a BMX style fork for strength and looks.
This bike used a Nexus 3 speed with coaster brake.