Author Topic: 71 Cb750 project help  (Read 1409 times)

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Offline 73nancy

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71 Cb750 project help
« on: November 20, 2008, 02:18:31 PM »
starting the tear down process on my 71 cb750 for a cafe build and have some questions. im wanting to make my own cafe seat from the stock pan. the plan was to use the stock pan with foam and glass over that and bondo to make the look i want. but after taknig the seat off today and reading all the post i could find in search the rear fender brace looks like an issue. im not using thr rear fender and i took that off but i dont know how to make my rear tail that will reach all the way to the end of the frame. my build will have a flat rectangular tail end in which im going to french in two cadillac tailights side by side. ive read other builds and would it be easier to make my tail out of metal. i have a english wheel and all the metal tools i need to work with. also the stock pan isnt totally flat so should i just scrap it for something eles or how can i mod. it.
my second question is which i know has been talked about as well is a front fork brace. since its a 71 750 i cant find anyone who makes a fork brace for it. im removing the front fender totally at this point so im unsure what to do. so if someone can point me somewhere it would be good. if anyone can make these i bet a bunch of people would want one. any help would be great
k1 cb750 cafe racer (aka Helter Skelter)
k6 cb750 stock daily rider project
k3 cb750 race bike 911 big bore, alum rods, 13:1, race cam other goodies

Offline kghost

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Re: 71 Cb750 project help
« Reply #1 on: November 20, 2008, 04:49:00 PM »
I'll take a stab.....

Seat Question: Its hard to modify the stock pan to get a good looking and fitting cafe seat. Someone here (I forget who) built a nice cafe rear section out of a Fuel tank from another bike (rear half). Personally I've had better luck just building a new pan. I'd then do the half tank trick.

Fork brace: I dunno where to get a 72 and below brace. I found one that fit another model and sectioned it in the middle and welded it back together to fit. What I look for in a usable brace is the diameter and size of the fork hole. Distance between fork centers I can fix or modify. Tire clearance is the same deal.

Stranger in a strange land

Offline 73nancy

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Re: 71 Cb750 project help
« Reply #2 on: November 21, 2008, 08:25:26 AM »
so as far as making a new pan what should i make it out of? i dont want to do a tank because i want a custome tail to fit my lights. still dont know about the fender brace just hack it off?

ya i dont know what to do on the brace i guess ill have to look for something close. from what ive heard on this board its not a good idea to run without something out front. has anyone ever done a stabilizer like a 1000c newer bike?
k1 cb750 cafe racer (aka Helter Skelter)
k6 cb750 stock daily rider project
k3 cb750 race bike 911 big bore, alum rods, 13:1, race cam other goodies

Offline greenjeans

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Re: 71 Cb750 project help
« Reply #3 on: November 21, 2008, 08:38:49 AM »
Its a 500 but done on the original seat pan....it can be done relatively easy

1st used self expanding foam - make sure you get a brand that is sandable and paintable



Then 3-4 layers or fiberglass,  then bondo to smooth out







http://forums.sohc4.net/index.php?topic=19789.0
« Last Edit: November 21, 2008, 08:42:26 AM by greenjeans »
Yep, I'm the kid that figured out how to put things back together...eventually.

fuzzybutt

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Re: 71 Cb750 project help
« Reply #4 on: November 21, 2008, 08:57:00 AM »
that looks fantastic greenjeans. i may do the same thing with my stock seat pan next year when i put the big motor in the k-4

Offline 73nancy

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Re: 71 Cb750 project help
« Reply #5 on: November 21, 2008, 09:38:15 AM »
great pics i remember looking at them in a diffrent thread. do you have a pic of the back end. my seat pan doesnt seem to cover the whole back half of the frame. did u extend the foam out past the pan or is it just siting on top. looks good.

also while im talking about you bike how easy were ur knee indents or is that a custom tank. thanks a bunch for the pics
k1 cb750 cafe racer (aka Helter Skelter)
k6 cb750 stock daily rider project
k3 cb750 race bike 911 big bore, alum rods, 13:1, race cam other goodies