duo-flex roadmaster.. DUO-FLEXMASTER

[bon]

hi guys! i'l be starting on my very first rat rod build this week(actually its not my first build, but will be my first radical build!), it was unfortunate i did not join the build-off because of time constraints, but these coming weeks i will have plenty of spare time.. hopefully will finish it in 2-3 weeks as i will be travelling and working abroad these coming weeks and will be gone in a year or two years.. i just hope i do finish this one and my other soon-to-be projects before i fly away. wish me luck.

recently i scored these two bikes, click the original link below from Fresh Finds. i scored an 54 Amf roadmaster and a Schwinn BF Goodrich straightbar, and they have mismatching parts installed in them. the schwinn has the CWC springer and the Amf has a columbia springer. so i correct them now, and the Amf got its original springer. i was told that this Amf is hard to restore because of the availability of most of the parts, like the tank and rack, so i just thought why not build it rat rod style and enjoy it. and here it goes.

viewtopic.php?f=16&t=57982

here is the current state of the bike.

i will be dismantling it tomorrow and might make the tank and seat also. i'm considering having the frame and fork powder coated black or just leave it bare metal. i'll also gonna fabricate the rear "springer" (someone here in rat rod bikes inspired me to think about this DUO-FLEX) and lets see where it goes.

 

[Cherryboxx]

Re: duo-flex roadmaster..

:shock: Purist turned Hotrodder? Hahaha welcome to the Ratrod Family,and Goodluck Bro.

 

[iven]

Re: duo-flex roadmaster..

:shock: Purist turned Hotrodder? Hahaha welcome to the Ratrod Family,and Goodluck Bro.

im a ratter cause of budget and style sometimes one over the other :roll: haha

 

[bon]

Re: duo-flex roadmaster..

thanks guys.

here's a minor update on the amf as i can't really do some progress on the frame yet because of heavy rains here in P.I.
I've already cut some pattern for the seat and tank out of some cardboard, and i've just finished the seat, already hammered to my specifications , and the tank is in line. i'm using an aluminum sheet with some checkered design, i hope it will look cool with the bike..

i've also made a pattern of the extension on the drop outs to mount the rear springs.. still wondering how to mount the springs, hopefully i get something out.

i've also stripped the springer fork, and had a machining shop fabricate some specialty nuts/ bushings for it to work properly.

i also found these lying around and probably will use them on the bike. the chainring i think is a murray? the stem, i dont know yet but i think i've seen it on some roadmasters, the lock nut is a little awkward, it has slits on both sides.

hopefully i make progress on the frame soon..

 

[bon]

Re: duo-flex roadmaster..

got some updates...

i had the frame sandblasted and it really looks straight.

i already fabricated the dropout extension. i used some old valve springs from some old cylinder heads that i have and here it is. i used a thick sheet of metal to make the extensions. i also found some special bolts.

then i had the brackets welded on to the frame and mock installed the spring hardware. sorry for the clumsy welding..

then i sent the frame and fork in the powder coating shop and it looks really nice, i picked FLAT BLACK.. here it is at the shop.

i have the frame and fork now and i'm starting to build this bike again. i'll post pictures later. hope you liked it.

 

[kingfish254]

Re: duo-flex roadmaster..

I missed the beginning of this one. Love to see another rear suspension mod. Looks like good engineering to me.

 

[bon]

Re: duo-flex roadmaster..

I missed the beginning of this one. Love to see another rear suspension mod. Looks like good engineering to me.

thanks kingfish, you're my inspiration! i love that bike you built and you gave me the idea. its sure sweet. i'm currently completing it and i'll post some pics soon.

 

[iven]

Re: duo-flex roadmaster..

looking good

 

[bon]

Re: duo-flex roadmaster..

looking good

thanks iven.

 

[bon]

Re: duo-flex roadmaster..

whoooo.... finally done with it. had a little trouble with the chain, the one that i bought was inches smaller, i needed to buy one more. here are the pics without the chain.

and with the chain and pedals. will still install the headlight and generator probably tomorrow. i hope you like it.

 

[kingfish254]

Re: duo-flex roadmaster..

Very cool!!!! That seat is killer!!

I do see a couple of potential engineering issues with the rear suspension though.

First, In order for it to function, it is going to need to pivot at both the springer arm joint and where it bolts to the old drops. The problem is that if you have the old drop connection loose enough for it to pivot then it is going to slide on the old drops. You can fix this by welding in a blank so the the old drop is just a hole rather than a sliding drop.

Second, the left and right springs are independent. This means that there could potentialy be times when the one side is more compresssed than the other and the axle would be tilted and the wheel would be cattywhompus. There may be enough shared surface area where the new drops overlap the old drops to help stiffen things up. You won't know until you ride.

It's all kinda tricky, that is why I built up a test rig on mine before any paint. I think the first issue is going to be your more pressing problem. Hopefully there is a way to solve it without messing up the paint.

Good luck buddy!

EDIT: One last thing to watch out for is your coaster brake arm. Having it connected to the stationary frame may bind up the left springer action. You may need to have a coaster brake brace that bolts onto the dropout pivot bolt like I did on Flexy.

 

[kingfish254]

Re: duo-flex roadmaster..

I missed the beginning of this one. Love to see another rear suspension mod. Looks like good engineering to me.

thanks kingfish, you're my inspiration! i love that bike you built and you gave me the idea. its sure sweet. i'm currently completing it and i'll post some pics soon.

I am honored that you found inspiration in Flexy. That is part of what this site is about. We are all part of this big creative collective mega brain.

I just noticed that this is your FIRST rat build. Man, you are showing some wicked skills and creativity. This build has a great stance and some super design elements. That seat is perfection!!!!

 

[bon]

Re: duo-flex roadmaster..

Very cool!!!! That seat is killer!!

I do see a couple of potential engineering issues with the rear suspension though.

First, In order for it to function, it is going to need to pivot at both the springer arm joint and where it bolts to the old drops. The problem is that if you have the old drop connection loose enough for it to pivot then it is going to slide on the old drops. You can fix this by welding in a blank so the the old drop is just a hole rather than a sliding drop.

Second, the left and right springs are independent. This means that there could potentialy be times when the one side is more compresssed than the other and the axle would be tilted and the wheel would be cattywhompus. There may be enough shared surface area where the new drops overlap the old drops to help stiffen things up. You won't know until you ride.

It's all kinda tricky, that is why I built up a test rig on mine before any paint. I think the first issue is going to be your more pressing problem. Hopefully there is a way to solve it without messing up the paint.

Good luck buddy!

EDIT: One last thing to watch out for is your coaster brake arm. Having it connected to the stationary frame may bind up the left springer action. You may need to have a coaster brake brace that bolts onto the dropout pivot bolt like I did on Flexy.

thanks kingfish254, the seat is really cool, even i didn't expect it to come out that neat.

by the way, thanks for the tips. i was following your build on FLEXY, and i already addressed those problems. regarding your first concern, the springer arm pivots freely and it doesn't slide in the old drop outs, i had a special bolt made thats kinda had to explain, but i'll try to post some pics of it. the nut is 17mm in size and also the bolt end, but after the thread, the body of the bolt gets bigger in diameter that corresponds to the hole in the springer arm, and this is a little thicker than the plate. kinda hard to imagine it right, well just gotta post some pics of it.

second, yeah the the left and right suspensions are indepent, i was also worrying about that and thats why i had the springs a little smaller but just the right stiffness to carry the load. i rode it last night for about 10 kilometers and it rides smooth, once you're on the seat, the springs are already compressing and they both play.

and lastly, the coaster arm brace, i already change it this morning, i used a larger brace, so it moves a freely..

thanks man! i'm thankful about FLEXY, it gave me these ideas.

 

[bon]

Re: duo-flex roadmaster..

I missed the beginning of this one. Love to see another rear suspension mod. Looks like good engineering to me.

thanks kingfish, you're my inspiration! i love that bike you built and you gave me the idea. its sure sweet. i'm currently completing it and i'll post some pics soon.

I am honored that you found inspiration in Flexy. That is part of what this site is about. We are all part of this big creative collective mega brain.

I just noticed that this is your FIRST rat build. Man, you are showing some wicked skills and creativity. This build has a great stance and some super design elements. That seat is perfection!!!!

thanks a lot.. I'm grateful. i'll update soon. by the way, the only problem i had last night when i rode it is the seatpost, i gave way, maybe i'm a little overweight, i need to have a bended one, not a welded one.

 

[kingfish254]

I am glad that you found ways to prevent the possible problems that I thought of. It's so cool seeing another builder's take of a rear suspension. Your's looks very cool and ingenius! I know that Raggedjim was also thinking of rear suspension bike. He put some uber cool faux springers on the back of Loco-Cycle.

Good luck with the seatpost. There is someone that sells laidback posts on the forum. Also, I bought one from Pirate Cycles online, but haven't used it yet on anything.

Keep up the cool work!!!

 

[bon]

I am glad that you found ways to prevent the possible problems that I thought of. It's so cool seeing another builder's take of a rear suspension. Your's looks very cool and ingenius! I know that Raggedjim was also thinking of rear suspension bike. He put some uber cool faux springers on the back of Loco-Cycle.

Good luck with the seatpost. There is someone that sells laidback posts on the forum. Also, I bought one from Pirate Cycles online, but haven't used it yet on anything.

Keep up the cool work!!!

many thanks, i've been a forum lurker for some time, but once you've tried RRB, you'll never gonna stop. but many thanks also to RRB for this awesome and cool site, really gives a broad knowledge to everyone of us.

Hey, that is cool.

thanks Peatbog. i hope you liked it..

 

[bon]

no time for some updates.. to time to take some pictures.. i am thinking of painting the rims red.. do i need to or just leave it as it is?

 

[someguy83]

.. i am thinking of painting the rims red.. do i need to or just leave it as it is?

I say leave them chrome. That way you don't have too many colors or finish types going here. If you do decide to paint them red be sure to scuff them really well and then prime with self etching primer, then follow with primer and top coat. If you paint the wheels though I think the handle bars would then stand out being the only chrome so you may want to scuff those then clear coat with low gloss so they then coordinate with the tank and seat. But whatever you do, enjoy it and great build by the way.

 

[Jake Sensi]

Leave em alone! Bike is killer! You've got some serious skills! GTB!! Peace

 

[bon]

.. i am thinking of painting the rims red.. do i need to or just leave it as it is?

I say leave them chrome. That way you don't have too many colors or finish types going here. If you do decide to paint them red be sure to scuff them really well and then prime with self etching primer, then follow with primer and top coat. If you paint the wheels though I think the handle bars would then stand out being the only chrome so you may want to scuff those then clear coat with low gloss so they then coordinate with the tank and seat. But whatever you do, enjoy it and great build by the way.

thanks man, i really need that. now i'll leave them alone.