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Oh, what the hey!

gbyoung2

Member
Member
Let’s modify a Triumph Trident rear sprocket to work on an “ancient” late ‘40s Velocette rear hub.

IMG_5151-XL.jpg


The piece you see in the mill is a stepped slug I turned to insure the rotary table is dead center with the quill once the end mill is inserted.

Still in the layout stage, and hope to have everything centered up and concentric so I can make some chips before the w/e. Basically, one shot at this, so keeping fingers crossed.


 
Wow Guy, I'm guessin' that '40's sprocket is either really expensive, or no longer in made?

Good luck!!
 
oh boy... that's a "big'n", 48 tooth?, I think you can get KZ' sprock's in that still.. I might have one, from back in my "MR. Riceburner Ent./ drag racing days"....    :rotflmao: :rotflmao: :rotflmao: :rotflmao:
 
connie_rider said:
So, what modification are you going to make?

Ride safe, Ted

Milling out the center, and cutting a relief to fit the hub + drilling holes for bolts that secure the two together.

EDIT: A couple of pix..........

The sprocket on the right is the original. And no, I did not count the teeth. The one on the left is a previously modified one done by another a year or so ago at a local machine shop. That fella has since passed, which is why I've been given the opportunity to modify another (the owner has two (2) Velocettes.
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The object on the left is the hub from one of the bikes. It's a combination sprocket carrier and brake drum. The sprocket on the right is the sprocket mentioned above with an approximation of how large the original center hole was prior to opening it up. The step relief will also need cut in the sprocket I'm working on now.
Img_5160-L.jpg


Both the sprockets are shown inverted from how they'll be bolted to the hub.
 
I follow ya.
But don't see how your gonna mill it out {as it is clamped}?

I did a similar project and cut the ID on a Lathe, then clamped in place to drill the holes.

Ride safe, Ted
 
i've done similar as well. lat time i made a fixture plate and bolted the sprocket to it to mount on the rotary table. i was using blank sprockets a s a start.

as an fyi, look up 'rebel gears' they probably can produce these, especially if you give them a sample or just dimensions. .
 
m in sc said:
i've done similar as well. lat time i made a fixture plate and bolted the sprocket to it to mount on the rotary table. i was using blank sprockets a s a start.

as an fyi, look up 'rebel gears' they probably can produce these, especially if you give them a sample or just dimensions. .

I'll pass the name along to the owner.

Thank you.
 
connie_rider said:
I follow ya.
But don't see how your gonna mill it out {as it is clamped}?

I did a similar project and cut the ID on a Lathe, then clamped in place to drill the holes.

Ride safe, Ted

Going to be done in stages, and still working out the final details in my head.

As far as using a lathe, the swing on mine can't accommodate the diameter of the sprocket I'm working on.
 
Mcfly said:
Wow Guy, I'm guessin' that '40's sprocket is either really expensive, or no longer in made?

Good luck!!

No longer made.

I did decide to count the teeth on it – 60T. It came from an off-road competition bike and the owner wants to convert it for limited street use. The 60T is not a good choice fo that - obviously.

The original modified sprocket was a 52T for something from England, and the one I’m getting ready to whack on is a 53T from a Triumph Trident. Fortunately, he’s in no big hurry, but I would still like to get it taken care of as soon as I can.
 
Almost there. Just have a little de-burring and I can turn it over to the customer.

Wound up having to make a holding fixture, the clamps wouldn't grip the sprocket tight enough and it wanted to shift. To complicate matters, the dang thing was warped slightly so it wouldn't sit flat on the table(s). Made the fixture out of 3/4" MDF. It ain't pretty, but it seemed to do the trick. Made the last cuts this evening, and glad to get this one out of my hair.

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Gone. The customer picked it up this morning. Seemed pleased, as am I for the rewards.... from a bux and experience standpoint.

Img_5210-L.jpg


Note: Ballos is a local machine shop that did the original sprocket. They've done cylinder boring work for me in the past. They do good work, but I have met a couple of folks whose projects are now in limbo due to their head machinist passing away suddenly about 6 mos. ago. No way in Hades could I fill that void, but if I can pick up something every now and again that I think I can handle, we'll give it a go.
 
I really hate to admit this,,, but, I gotta say,,, Ya did good.
            "Exceptionally well done" Buddy!

Ride safe, Ted
 
Remember this little project of mine?

Well, back when I was doing this, I found another Trident rear sprocket over in the UK to have on hand JIC I screwed up with this mod. Turned out I didn't need it, return shipping to back over there bordered on the ridiculous, so listed it on eBay. That was Sept. 15. Had it all boxed up and everything ready to go. A quick sale never happened, I tucked it away and I forgot about it. Until yesterday.

I got a note through eBay that the item had sold. Wonderful, but oh poo - where in Hades did I stick that thing? That bugged me as I was laying in bed unable to sleep, so I got up about 12:30 and went out to the garage to look for it. Wasn't exactly where i thought it was, but close enough that I found it Whew!

Next issue was how I was going to get it to the USPO. Loving wife forbids me from venturing out into the "hot zones." I sent a note to the buyer telling him that shipping may be delayed and I could cancel if he wished. In the interim I got a hold of a neighbor up the street who is still running around, and asked if he'd carry it to the PO. Said he would, so got a label printed and stuck it out on a wall on our carport, along with an envelope with some $$ for the postage.

He got it mailed, returned the change and receipt in the envelope, stuck it back on the wall under a stone so it wouldn't blow away, and left. No close contact with one another, which is good.

Handling cash these days is BAD, so the envelope made it out to the garage, I was able to get the receipt out to copy down the tracking number so I could send it along.

Done!!!

 
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