(ORBO) BMX/MTB/BOMBER/KLUNKER BO .....VOTING FINISHED!......

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LIVE TO RIDE said:
Haha no kidding!!!But a klunker to me is a pre war to 70s fat tire frame that has been modified from its original stock state to endure downhill beatings.Klunkers were bikes built by some of the first adrenaline junkies that started what is mountain biking today.Just tried to post a youtube link to ''Klunkerz'' the video made about the early days of klunking but wont let me link it.But cant wait to see the entries for this build off!!
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my deffinition is about the same , a vintage frame set up with modern mtb parts , witch is what they did back then , adding gears ,better brakes, off road tires to make the best out of there old junkers
 
OneHorsePower said:
my deffinition is about the same in definition , a vintage frame set up with modern mtb parts , witch is what they did back then , adding gears ,better brakes, off road tires to make the best out of there old junkers
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They couldn't have done that "back then", as there weren't any "modern mtb parts" available in the 70s... They used BMX, Tandem, and Touring parts to get low gears and stronger components....

To me, it's a klunk if you take a frame that wasn't intended for trail use, but then try to maximize it's trailworthiness via modifications.... as simple as adding knobby rubber, to as involved as frame mods to allow gears, suspension, whatever. A "classic klunker" would be a pre-war to '50s balloon-tire frame with knobbies and front or front/rear handbrakes. Once you add derailers to that equation, you got a "hybrid"... If you simply strip the extraneous bits (fenders, chainguard, kickstand, tank) from a balloooner and get some better rubber, you got a "bomber"--one speed, coaster-only madness. But, "klunker", to me, is a general term for taking a bike meant for paved surfaces, and optimizing it for the trail anyway---in other words, taking the proverbial "fish out of water" and enabling it to fly down the trail.

I been into building "industrial klunks" for a few years now. Worksman INBs, Schwinn Heavy Dutis, Summits, and Huskies all have elements in common with the old-time cruisers, but they're readily available, cheap, and still in-production, so i don't feel guilty about killin' an irreplaceable piece of bicycle history...
 
And they're yummy... might just have to build more than one bike this year.

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chattymatty said:
And they're yummy... might just have to build more than one bike this year.

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Gotta love MAFACS.... I have a soft spot for the centerpull MAFACS that go on their own bosses.... not Cantis, but like proto-U brake centerpulls. Such hott brakes.... but those Cantis you got have the geometry nailed down... much better feel and power out of those than in most of the cantis made since. (Low-pro Cantis aren't nearly as good....)
 
Bicycle808 said:
What frame are you lookin for?
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A chromo, 17 inch late 80s or early 90s MTB frame, straight bar, light in weight as I only weigh 155 pounds. I want to make it like a Transitions Klunker but I hate their bike as it has a threadless fork. I want a light rigid frame that I can put my old drum brakes on alloy wheels. I would like to mod the frame to look sort of like a Transitions Kunker. Perhaps even using a Koski Brothers fork? Koski Brothers now has the Bro Cruiser with a short chain stay and long top tube so it feels like an old clunker but rides real stable at high speeds because of the short stays and head tube angle. It has a double top tube but it looks too funky for me. The Koski Brothers bike frame gets high praises. I have a light rigid mtb now, but it is 15 inch and the top tube is 20 only inches. My 1940s Klunker has a 22.5 inch top tube. The rest of the measurements on the 15 inch frame are close to my real clunker except the mountain bike has a much improved shorter chain stay. The fork angle is more lax on the clunker and would be improved using a rigid mountain bike. Ideally I should just buy the Transitions Klunker and put my brakes on it. It would be cheaper but as I said I don't like the modern headset and bottom bracket. I will probably not be able to find a lightweight old mountain bike frame with a one piece bottom bracket so that will have to be a compromise. I also would like gears, which a mtb is set up for already but if I can't modify my rear hub I may have to go with a single speed. My rear drum came from a single speed bike so I still have to figure out a longer axle for it if I want to use a gear cluster and figure the exact size spokes, somewhere around 9 7/8" by 3x. I tried to lace up the rear drum last summer but that was a disaster as the spokes were too long. If I find a 17 inch frame it would have to have a longer top tube (not necessarily 22.5" but more than 20") so it all depends on what I can find.
 
Yeah, you're DQ'd from reality insofar as wanting a light mtb with an American BB shell. Otherwise, that's a laudable goal. I think that mtb geometry switched to something quite usable offroad in the 90s, with the standard "NORBA" geometry (short stays, long sloping toptube, steeper angles), but some earlier bikes (Fat Chance comes to mind) looked similar.

Funny you mention Koski. I've always admired their products. The original Pro Cruiser was a groundbreaking frame; it had slack angles of the earliest bikes, but it had the short stays and long TT of later bikes. I'd never heard of any new-production Koski stuff, much less a "Bro Cruiser", so I googled it. Very little info came up at all, but I did find their FB page and some intriguing pics of a twin toptube full-rigid bike with discs and more progressive geometry. Is this the "Bro Cruiser" you speak of? https://www.facebook.com/KoskiBros....918247729487/1521937328060912/?type=1&theater
Regardless, that's an impressive frame....

It'd be easy enough to put some headtube reducers in the Transition bike to run a threaded fork, but the transition has super long stays anyway. The Transition guys claim they aped the Worksman INB's geometry as a basis for their "Klunker"s dimensions and angles. Interesting. I gotta say, although I like the look of a threaded 1" headset/quill set-up, 1.125" threadless is definitely a more robust design for offroading. And, the "mid" bb shell is pretty sweet, too... I run some tubular bmx-type 3 pieces on some klunks anyway, and the "mid" set-up is essentially an American BB except that it obviates the need for press-in cups. You can run any 3-piece set up for an American shell, and you might even be able to run a 1piece if you took a BB220SB's hardware and got creative with some quasi-standard cartridge bearings. But, the Transition's geometry is a deal-breaker for you anyway; it has the same geometry you're trying to avoid, plus it uses newer standards that you dislike. And, it ain't exactly lightweight. You'd be better off with a Worksman from Chuckz....

I think you could probably find a mid-90s full rigid bike for fairly cheap, and cut out the shell and weld in an American shell yourself.... or, have someone else do it for you. By then, a lot of the bikes were already 1.125", but you could use reducers or just look for a Bridgestone MB-_ series bike, which will have 1" threaded set-ups. If it were me, though, I'd just live with the BSC-style BB shell and the vast array of stiff, light, versatile cranks that work with it....
 
Bicycle808 said:
Yeah, you're DQ'd from reality insofar as wanting a light mtb with an American BB shell.
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Still fine for the build-off though as it includes MTB's and Adult sized BMX as well! :thumbsup:

Luke.
 
Bicycle808 said:
Yeah, you're DQ'd from reality insofar as wanting a light mtb with an American BB shell. Otherwise, that's a laudable goal. I think that mtb geometry switched to something quite usable offroad in the 90s, with the standard "NORBA" geometry (short stays, long sloping toptube, steeper angles), but some earlier bikes (Fat Chance comes to mind) looked similar.

Funny you mention Koski. I've always admired their products. The original Pro Cruiser was a groundbreaking frame; it had slack angles of the earliest bikes, but it had the short stays and long TT of later bikes. I'd never heard of any new-production Koski stuff, much less a "Bro Cruiser", so I googled it. Very little info came up at all, but I did find their FB page and some intriguing pics of a twin toptube full-rigid bike with discs and more progressive geometry. Is this the "Bro Cruiser" you speak of? https://www.facebook.com/KoskiBros....918247729487/1521937328060912/?type=1&theater
Regardless, that's an impressive frame....

It'd be easy enough to put some headtube reducers in the Transition bike to run a threaded fork, but the transition has super long stays anyway. The Transition guys claim they aped the Worksman INB's geometry as a basis for their "Klunker"s dimensions and angles. Interesting. I gotta say, although I like the look of a threaded 1" headset/quill set-up, 1.125" threadless is definitely a more robust design for offroading. And, the "mid" bb shell is pretty sweet, too... I run some tubular bmx-type 3 pieces on some klunks anyway, and the "mid" set-up is essentially an American BB except that it obviates the need for press-in cups. You can run any 3-piece set up for an American shell, and you might even be able to run a 1piece if you took a BB220SB's hardware and got creative with some quasi-standard cartridge bearings. But, the Transition's geometry is a deal-breaker for you anyway; it has the same geometry you're trying to avoid, plus it uses newer standards that you dislike. And, it ain't exactly lightweight. You'd be better off with a Worksman from Chuckz....

I think you could probably find a mid-90s full rigid bike for fairly cheap, and cut out the shell and weld in an American shell yourself.... or, have someone else do it for you. By then, a lot of the bikes were already 1.125", but you could use reducers or just look for a Bridgestone MB-_ series bike, which will have 1" threaded set-ups. If it were me, though, I'd just live with the BSC-style BB shell and the vast array of stiff, light, versatile cranks that work with it....
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I passed on a cherry Bridgestone MB5 last summer, Dah, it was free.
Thanks for the info. Yeah 38 pounds for the Transition is what my CWC Clunker weighs with a front drum brake. Yeah, the bb will have to be left alone and would work with what I would use anyway. I wouldn't bother to replace the bb and then convert it back. I like the Koski bike and if I had more $ I would go for it. The Bro Cruiser has 27.5 wheels twin top tubes and the frame is made for Koski Bros. by Sherwood Gibson of Ventana Mountain Bikes at least that is the word. It comes in rigid and front suspension with disc brakes. I found it on Facebook from a tip by Alan Bonds of Clunker fame. Alan said this bike is supposed to feel like the old clunkers but very stable and forgiving at high speed. Alan recommended it for me as is like but better than. This would probably be the easy way for me, just buy a Koski. The page you referenced with the bike pictures is the bike I am speaking of. Too many cool bikes out there to ride.
 
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Bicycle808 said:
So, what cranks would u wanna use?
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Cotterles Stronlight or Sugino ideally but anything I can find. I had 3 sets last summer but gave them away. Seem like you come across stuff you don't need and when you need it it is suddenly hard to find. I know where there was a 70s Fuji road bike for sale cheap last summer, too big for me but I could use the parts for this idea. I may go back and see if it is still for sale or if he gave it away.
 
Oh, well, you oughta just find a good Specialized, Kona, Trek, or really any good MTB from the 90s, and roll. Absolutely crazy to seek out a frame with an American shell if you're just gonna run a BSC/"Euro" adaptor anyway... the bikes with the geometry and lightweight tubing will all have a threaded BSC shell as standard...

I think my Kona would look rad with a mid-tube welded in there.... something I've thought of in the past, but cannot really justify. It's just a chromoly full-rigid, 3x9 gears, v-brakes, decent stuff I'd built it up with, but ppl are usually surprised by the "light weight", mostly b/c folks are used to the front-heavy bikes of today, with suspension forks and discs. My mtb is well-balanced, mostly b/c no one part or system is overweight...
 
Bicycle808 said:
Oh, well, you oughta just find a good Specialized, Kona, Trek, or really any good MTB from the 90s, and roll. Absolutely crazy to seek out a frame with an American shell if you're just gonna run a BSC/"Euro" adaptor anyway... the bikes with the geometry and lightweight tubing will all have a threaded BSC shell as standard...

I think my Kona would look rad with a mid-tube welded in there.... something I've thought of in the past, but cannot really justify. It's just a chromoly full-rigid, 3x9 gears, v-brakes, decent stuff I'd built it up with, but ppl are usually surprised by the "light weight", mostly b/c folks are used to the front-heavy bikes of today, with suspension forks and discs. My mtb is well-balanced, mostly b/c no one part or system is overweight...
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Not gonna seek a frame with an American Shell as I don't think they exist with what I want. It is sort of like the ultimate wish list. I will keep collecting parts and see what I can come up with?
 
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