TOPIC:

So, I have an 82 550 LTD with the TK22 carbs. Of course, when I got the bike, there were no choke flaps. I just made do by stuffing a rag in the airbox intake when it was cold out. Pain in the ass. So then last summer I epoxied the slides shut. Starts great, but problem is you are CONSTANTLY fiddling with the choke when you take it down the road. I'd start off at 75% choked. Then when I hit 10 mph would have to open it some. Get to a stop sign and try to get it back to 75% again, along with traffic...bigger pain in the ass.

So, I happened to have 1 flap from a set of parts carbs. I set off to fabricating. Now, let me remind you, I am not a machinist and don't have steady hands and have even less patience. I used mainly my dremel with a cutting wheel and a grinding stone to smooth stuff out. I used a 0.010" thick stainless steel shim that I got from work. They use them for shimming big electric motors for alignment purposes.

Anyway, the little tab on the shim is damn near the curvature of the flap. Of course I tried this first, but hacked it up and had to start over.

After a while I managed to get a working prototype, as can be seen in the pics. Now, the only real issue I have is if the flap opens past 90 deg or so (I'm not sure if it will lift that far open? - Lou, do you know?) it can shimmy over a hair and get caught on the side of the slide, causing it to hang open. On my next flap, I'll make the tangs just a bit wider so they do not allow any side to side movement when the flap is open.

The 0.010" shim seems thinner than the stock one. I also have a 0.015" shim that appears to be pretty close to the stock flap, but I figured I try the thinner one first, since it would be easier to cut. However, it does not seem like the thin one flexes at all, so I think I'm going to stay with it.

Believe it or not, the hardest part of this whole operation was getting the damn spring on the pin without it going BOING! and flying across the garage. More to come once a nab another shim from work.

Looking good. From the outside, it looks as good as the original.

The main question is, will it be strong enough?

I don't think the flaps open near 90 deg, but I've never wathed them.
But they do probably flap like crazy... more like a vibration, so those suckers have to be strong.

well, it is 0.005" thinner than the original, but it is stainless steel vs what I think is aluminum??

When you say strong enough, are you referring to flexing or the hinges breaking like the originals do? My plan is once they are installed and show me they work, I'll do inspections of them often. I think I should be able to leave the carbs on the bike and pull the slides out from the top. I still need to find something...a washer, spacer, something to put on either side of the tangs to keep it from walking over a bit and getting hung up. On later fab's I'll trying to make sure the tangs are close enough to the slide body to not allow this, but it's pretty tricky when doing it free hand with a dremel.

The flaps are definitely steel. I think zinc plated.
They don't appear to be unusually hardened or anything. I think brittleness would be bad.
They tend to break at the hinge curl, like in this photo.



On Mstbone's home-made flap, he used one big hinge curl with the spring off to one side so the spring's arm hits the center of the flap.

You're right...never noticed that. I'll have to ponder this. Would be much easier making the hinge flap.

Ok, I thought about his design, and I'm curious if the spring isn't centered if the flap can get cockeyed and hang up...

hey fellas, I ended up fabbing up my flaps like above. WOW what a difference! I can start it and actually motor around with the choke on without working the choke as much as the throttle.

The one thing I'm worried about, is stainless more brittle than regular steel? If so, my design might not be that great...

At any rate, I'm very happy with them now.

Would a common hose clamp work or is that too thick? I compared a piece of the broken flap side by side next to one and it seemed to be the same thickness of it. Im having the same issue and have to make these myself, first i thought i use the metal from those Tin Pan Cookie bins since they are very easy to bend, but seem they will warp or give way over time. At the moment im trying cut/shape these hose clamp into flaps. Almost done shaping the first prototype.......Urgent feedback/advice is greatly appreciated.

Looks good! Could be a tad too thick/heavy for the spring to allow the flap to open, as designed, but try them and let us know.

Looking good so far.

so i just found out im gonna have to make one for my bike what im wondering how does a flap just disappear. im not the first owner so idk if they just didnt put it back together right or what but the flap is just gone. thanks for the info.