Bonanza chopper repairs


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I bought a bonanza chopper project off member Cdownie this weekend (he actually hooked me up with a trailer load of stuff :thumbsup:), I had figured on probably just tossing this actual frame in the garbage due to all the mods but I figured I may as well see what happens if I start cuttin' on it as the frame really was not as bad as it looked in the photos.

Here it is in all its glory, Had some big plates welded on for a sidecar at one time, engine plate cut off and moved forward, original footpegs removed and big honking footbar welded to the front of the moved plate, right frame notched out for a briggs, brake mount tab relocated etc..

Spent the morning going thru cut off wheels and discs, got it this far and will use the other frame for measurements.

Maybe I can save it I dunno :shrug: Garbage day is friday, I have till then :laugh:


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If you end up tossing things, I could really use that engine plate if it were to otherwise go in the garbage.


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Well looks like the Garbage man is only going to have couple of engines and some pieces of scrap to deal with tomorrow, no frames :thumbsup:

I had hoped to get more than this done but I have a houseguest right now and have been trying to keep the noise down, so I have only been able to make a racket when they are out and about :no: The engine plate came out pretty good, they didnt hack into the slots too much just some extra holes and divits.

Its another one of my re-"cycle" jobs, the replaced tubing on the toprail, and the foot pegs are sections of tubing off an old Powerdyne frame I have been cutting pieces off as needed (its just about given all it can at this point). The inner sleeves I used to splice the rail together are a piece of frame section off The 1980 Honda CR80r that Chris used as a donor for his CR80 powered Sears Roper he did in the buildoff this year. He threw the remains of that bike in with these choppers when I bought them to get it out of his shop. Someone in my Neighborhood restores and customizes vintage Honda Cubs and he wanted the forks to adapt to a custom cub so that bike is still getting re-cycled some more as well :thumbsup:

Next stop will be the forks, They are a real mess too :doah:


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You know how when you pull and old bike apart with sloppy forks and the bolt is all hourglassed out from the plate wearing into it....These guys took a washer and wedged it while on the the bike into the hourglass and then did that wonderful weld job :doah: I didn't need a nut to keep it from coming out. All the cut marks were from me trying to carve around and thin the bolt down so I could drive it though with the air hammer...while still on the bike.

But its all better now :thumbsup:

I also spent some time with the press, getting things straightened up more. The main tube of the cut up CR80 frame yielded me some fresh sections of tubing to cradle the fork legs and bars to help prevent dings, even had a convenient brace section that I used for the press rod to push on :thumbsup:



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That's awesome Markus. That sloppy mess on the fork plate reminds me of how my Flexo was. Great job.:thumbsup:
This was a cakewalk compared to the stuff you had to do to that thing!!!!!! The fork repair pretty much puts me over the hump now Think I have all the major repairs completed thankfully :thumbsup:


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Finished the fiberglass repairs to the blasted out holes in the front of the pan this morning and as soon as I stop itching its getting boxed up and shipped off to Karens Kustom seat salon for a revamp. Which hopefully will be my only Major expense for this bike (roller at least) as its looking like I can save most everything else at this point :thumbsup: If I choose to go back to Orange on the frame I will have to buy color but I should have enough supplies in the cabinet for the primer/prep etc..

will be spending some quality time hunched over the blast cabinet later working on the wheels and hardware getting that stuff ready.


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Thanks everyone :thumbsup:

Today I pretty much finished up all the cleanup and prep work on the hardware to get ready to try and zinc it. with the exception of one seat bolt the bike still had I believe all its OG hardware. I did have to sacrifice the head tube bolt as noted in a previous post. I don't have any R B W stamped 5/8" bolts left to replace it with :angry: I spotted another bike I have that does use that stamping though and I may just swap that over to an unmarked one I have so I can drop the RBW to be zinced along with this stuff (that bike is not a Bonanza, Rupp, or Taco, so who cares if all the hardware matches :laugh:) I was able to cheat on the one seat bolt since the other was not a marked head. I worked off the markings on the new one I had to match it. The eyebolt adjusters have seen better days, The threads got a little chewed I re threaded them as best I could, the nuts were toast so they will have to get replaced but those are are easy to replicate since they are not any type of locknut.

I've only done a real quick and light blast on the wheels with the tires on so I could clean off the buildup/rust on the threads of the bolts so they would come out easy one not tear up the wheel. They are really clean overall even on the inside so they will clean up really nice and pretty easy. The original bolts came out really easy with an initial whack from an impact driver with no damage :thumbsup: Not sure if I will use the round tank or not, its the only large one I have left. that will depend on how far I take this project and what power I decide to go with, I never seem to get that far since bikes are worth more and easier to sell off parted out that complete :facepalm:


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Been watching this frame rust away in the shop :doah: so while I was working on another bike frame that needed another run of high build laid down I prepped this one and got the first heavy dousing of high build primer dumped on it at the same time. Its not pitted but alot of cuts and scrapes from all the plates that had been added onto it. I figure its going to need 2 runs of high build and blocking out to get it pretty decent.

and while I was waiting for the high build on the other frame to setup I grabbed the forks and did some surgery. I had asked about how they actually are put togother in another thread and never got an answer, will What I found is that the Upper section is only welded to the top of the lower tree, the lower weld is only holding the lower part of the forks to the plate. These had the usual goober repair weld at that upper seam, I tried to work around it, got mad and just sliced it right off flush and then drove out the remaining tubing section from inside the bottom section.

I guess I am going to sleeve it there to get the upper parts back to the way its supposed to be. press it all bac together and and run a cleaner weld at athat point in hopes that they will look presentable. I wont be chroming them but I want to try and make them re-chromable for the next guy/gal down the line that actually has money to work with at least.

Iron Honky hooked me up with the Scout style chainguard for this recently, I also found a correct sized round tank on ebay as well, so I have that option for it too and not have to use use the other tank I had (it was an inch or so too long anyway) I just recently picked up an original headlight and taillight kit too, they are pretty nasty condition wise though so I dont know if I will use them or not.


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Finally drug this out and got some color laid down on it today, I used a 1969 Camaro orange as I had seen it referenced as being a decent match for the Bonanza orange. I used a single stage Dupont Nason urethane paint, I used grey primer sealer though so it may be a touch darker than intended (its also pretty dark in my cave of a garage).

Since I can't afford to run with the big dogs and chrome my alternative to cover the extensive repairs on the bars was paint. Not in love with doing this but it what I had to do:

I ended up sleeving the fork upper fork section bringing tubing up into the bars past the top tree and flush with the upper section so it wont interfere with the bottom pieces that bolt in. It got welded at the top seal like it should and I did my best to make it that it could be worked with and chromed maybe by someone if they really wanted to still. It shroud also be a little stronger at that point which seems to be an issue with these chopper forks.


New Member
This looks like a really sweet project. I've never sprayed an orange, but I know deep reds are often tri-stage. That paint looks great for a single stage though! I can't wait to see more.